WorldWideScience

Sample records for asphalt tests

  1. Finite element simulation of asphalt fatigue testing

    DEFF Research Database (Denmark)

    Ullidtz, Per; Kieler, Thomas Lau; Kargo, Anders

    1997-01-01

    The traditional interpretation of fatigue tests on asphalt mixes has been in terms of a logarithmic linear relationship between the constant stress or strain amplitude and the number of load repetitions to cause failure, often defined as a decrease in modulus to half the initial value. To accomod......The traditional interpretation of fatigue tests on asphalt mixes has been in terms of a logarithmic linear relationship between the constant stress or strain amplitude and the number of load repetitions to cause failure, often defined as a decrease in modulus to half the initial value....... To accomodate non-constant stress or strain, a mode factor may be introduced or the dissipated energy may be used instead of stress or strain.Cracking of asphalt (or other materials) may be described as a process consisting of three phases. In phase one diffuse microcracking is formed in the material...... damage mechanics.The paper describes how continuum damage mechanics may be used with a finite element program to explain the progressive deterioration of asphalt mixes under laboratory fatigue testing. Both constant stress and constant strain testing are simulated, and compared to the actual results from...

  2. Effects of reclaimed asphalt pavement on indirect tensile strength test of conditioned foamed asphalt mix

    Science.gov (United States)

    Yati Katman, Herda; Rasdan Ibrahim, Mohd; Yazip Matori, Mohd; Norhisham, Shuhairy; Ismail, Norlela

    2013-06-01

    This paper presents the results of Indirect Tensile Strength (ITS) Test for samples prepared with reclaimed asphalt pavement (RAP). Samples were conditioned in water at 25°C for 24 hours prior to testing. Results show that recycled aggregate from reclaimed asphalt pavement performs as well as virgin aggregate.

  3. Effects of reclaimed asphalt pavement on indirect tensile strength test of foamed asphalt mix tested in dry condition

    Science.gov (United States)

    Yati Katman, Herda; Rasdan Ibrahim, Mohd; Yazip Matori, Mohd; Norhisham, Shuhairy; Ismail, Norlela

    2013-06-01

    Indirect tensile strength (ITS) test was conducted to analyse strength of the foamed asphalt mixes incorporating reclaimed asphalt pavement. Samples were tested for ITS after cured in the oven at 40°C for 72 hours. This testing condition known as dry condition or unconditioned. Laboratory results show that reclaimed asphalt pavement (RAP) contents insignificantly affect the ITS results. ITS results significantly affected by foamed bitumen contents.

  4. Viscoelastic Analysis of Asphalt Mixture Based on Creep Test

    Directory of Open Access Journals (Sweden)

    Lihua Zhao

    2013-01-01

    Full Text Available Two kinds of mineral fibers were added to AC-16C asphalt mixture. Trabecular bending creep experiments of asphalt mixtures were carried out at -10 and 20°C. The influence of mineral fibers on the low temperature viscoelasticity of asphalt mixtures were analyzed systemically. Furthermore, by using Origin, Burgers viscoelastic model was used to investigate the parameter regression for the creep test results at the different temperatures. The results show that the addition of mineral fibers can effectively improve the bending creep rate of asphalt mixtures, indicates the increase of crack resistance of asphalt mixtures. Good agreement between experimental data and Burgers model was found. The parameters of Burgers model at different temperatures can also provide data support for the viscoelastic design of asphalt pavements.

  5. Rutting Resistance of Asphalt Overlay with Multilayer Wheel Tracking Test

    Institute of Scientific and Technical Information of China (English)

    LIAO Weidong; CHEN Zheng; WU Shaopeng; MO Liantong; LIU Gang

    2006-01-01

    The rutting resistance of multilayer asphalt overlay was researched by using laboratory wheel tracking test. The effects of loading level and test temperature on rutting resistance of asphalt overlay structure were evaluated by means of multilayer specimens .In comparison with multilayer tests, standard specimens of various layers were also conducted to evaluate the rutting resistance. Experimental results indicated that the test temperature and applied load have a significant effect on rutting resistance of asphalt concrete. Higher test temperature and heavier applied load resulted in higher rut depths. In addition, the mutilayer wheel tracking test has been demonstrated to be a more reasonable solution in evaluation on rutting resistance of asphatt pavement structure beasuse it reflects the cumulative permanent deformation in all of asphalt layers.

  6. Asphalt and Wood Shingling. Roofing Workbook and Tests.

    Science.gov (United States)

    Brown, Arthur

    This combination workbook and set of tests contains materials on asphalt and wood shingling that have been designed to be used by those studying to enter the roofing and waterproofing trade. It consists of seven instructional units and seven accompanying objective tests. Covered in the individual units are the following topics: shingling…

  7. Hanford Permanent Isolation Barrier Program: Asphalt technology test plan

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Romine, R.A.

    1994-05-01

    The Hanford Permanent Isolation Barriers use engineered layers of natural materials to create an integrated structure with backup protective features. The objective of current designs is to develop a maintenance-free permanent barrier that isolates wastes for a minimum of 1000 years by limiting water drainage to near-zero amounts. Asphalt is being used as an impermeable water diversion layer to provide a redundant layer within the overall barrier design. Data on asphalt barrier properties in a buried environment are not available for the required 100-year time frame. The purpose of this test plan is to outline the activities planned to obtain data with which to estimate performance of the asphalt layers.

  8. Effectiveness of Micro- and Nanomaterials in Asphalt Mixtures through Dynamic Modulus and Rutting Tests

    Directory of Open Access Journals (Sweden)

    Hui Yao

    2016-01-01

    Full Text Available The objectives of this research are to use micro- and nanomaterials to modify the asphalt mixture and to evaluate the mechanical performance of asphalt mixtures. These micro- and nanomaterials, including carbon microfiber, Nanomer material, nanosilica, nonmodified nanoclay, and polymer modified nanoclay, were selected to blend with the control asphalt to improve the overall performance of the modified asphalt binders and mixtures. The microstructures of original materials and asphalt binders were observed by the field emission scanning electron microscope (FE-SEM. The mixture performance tests were employed to evaluate the resistance to rutting and permanent deformation of the modified asphalt mixtures. Test results indicate that (1 the dynamic modulus of micro- and nanomodified asphalt mixtures improved significantly; (2 the rutting susceptibility of the modified asphalt mixtures was reduced significantly compared to that of the control asphalt mixture; (3 the microstructures of modified asphalt binders were different from the control asphalt, and the structures determine the improvement in the performance of modified asphalt mixtures. These results indicate that the addition of micro- and nanomaterials enhanced the rutting performance and strength of asphalt mixtures. In addition, the analysis of variance (ANOVA was used to analyze the modifying effects of micro- and nanomaterials on the performance.

  9. SGC tests for influence of material composition on compaction characteristic of asphalt mixtures.

    Science.gov (United States)

    Chen, Qun; Li, Yuzhi

    2013-01-01

    Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes.

  10. Full-Scale Accelerated Pavement Testing of Warm-Mix Asphalt (WMA) for Airfield Pavements

    Science.gov (United States)

    2014-01-01

    ER D C/ G SL T R -1 4 -3 Full-Scale Accelerated Pavement Testing of Warm-Mix Asphalt (WMA) for Airfield Pavements G eo te ch n ic al...2014 Full-Scale Accelerated Pavement Testing of Warm-Mix Asphalt (WMA) for Airfield Pavements Mariely Mejías-Santiago, Jesse D. Doyle, and John F... asphalt (WMA) mixtures designed for airfield pavements. Three WMA mixtures were evaluated and compared to a control hot-mix asphalt (HMA) mixture. Data

  11. Study on triaxial test method and failure criterion of asphalt mixture

    Directory of Open Access Journals (Sweden)

    Jianlong Zheng

    2015-04-01

    Full Text Available Asphalt mixture is the most widely used pavement material all over the world. In China, more than 90% of service expressways are asphalt pavement. However, current asphalt pavement design method still has irrationality. Even though maximum tensile stress theory is used as failure criterion, pavement structure under the effects of wheel load is in three-dimensional complex stress state. Obviously, one-dimensional strength theory cannot reflect the failure characteristics and the resistance of pavement structure. So it is necessary to study the failure criterion of asphalt mixture under three-dimensional complex stress state. Due to limitations of test equipment, there are almost no studies in related area. Under this background, this paper develops a new triaxial test method, according to the investigation of strength characteristics of asphalt mixture under complex stress state through plane isobaric/axial tensile test, plane isobaric/axial compression test, plane tensile and compression/axial tensile test, to reveal the general rules of asphalt mixture's strength failure. The failure mode is divided into three types: tensile failure, shear failure and rheological failure. The tensile meridian and compression meridian in the stress space and strength envelope in the π plane where hydrostatic pressure is greater than zero are obtained, and the failure criterion of asphalt mixture under complex stress state is established, providing theoretical method and scientific basis for structure design as well as strength check of asphalt pavement under three-dimensional stress state.

  12. Asphalt Mixture Fatigue Testing: Influence of Test Type and Specimen Size

    NARCIS (Netherlands)

    Li, N.

    2013-01-01

    Fatigue characterization of an asphalt mixture is commonly estimated by laboratory fatigue tests. Based on the classical fatigue analysis, fatigue lives obtained from different test devices are not comparable even when they are performed at the same test conditions. It is believed that there are tw

  13. Characteristics of dynamic triaxial testing of asphalt mixtures

    Science.gov (United States)

    Ulloa Calderon, Alvaro

    Due to the increasing traffic loads and tire pressures, a serious detrimental impact has occurred on flexible pavements in the form of excessive permanent deformation once the critical combination of loading and environmental conditions are reached. This distress, also known as rutting, leads to an increase in road roughness and ultimately jeopardizes the road users' safety. The flow number (FN) simple performance test for asphalt mixtures was one of the final three tests selected for further evaluation from the twenty-four test/material properties initially examined under the NCHRP 9-19 project. Currently, no standard triaxial testing conditions in terms of the magnitude of the deviator and confining stresses have been specified. In addition, a repeated haversine axial compressive load pulse of 0.1 second and a rest period of 0.9 second are commonly used as part of the triaxial testing conditions. The overall objective of this research was to define the loading conditions that created by a moving truck load in the hot mixed asphalt (HMA) layer. The loading conditions were defined in terms of the triaxial stress levels and the corresponding loading time. Dynamic mechanistic analysis with circular stress distribution was used to closely simulate field loading conditions. Extensive mechanistic analyses of three different asphalt pavement structures subjected to moving traffic loads at various speeds and under braking and non-braking conditions were conducted using the 3D-Move model. Prediction equations for estimating the anticipated deviator and confining stresses along with the equivalent deviator stress pulse duration as a function of pavement temperature, vehicle speed, and asphalt mixture's stiffness have been developed. The magnitude of deviator stress, sigmad and confining stress, sigmac, were determined by converting the stress tensor computed in the HMA layer at 2" below pavement surface under a moving 18-wheel truck using the octahedral normal and shear

  14. Performance testing of asphalt concrete containing crumb rubber modifier and warm mix additives

    Science.gov (United States)

    Ikpugha, Omo John

    Utilisation of scrap tire has been achieved through the production of crumb rubber modified binders and rubberised asphalt concrete. Terminal and field blended asphalt rubbers have been developed through the wet process to incorporate crumb rubber into the asphalt binder. Warm mix asphalt technologies have been developed to curb the problem associated with the processing and production of such crumb rubber modified binders. Also the lowered production and compaction temperatures associated with warm mix additives suggests the possibility of moisture retention in the mix, which can lead to moisture damage. Conventional moisture sensitivity tests have not effectively discriminated good and poor mixes, due to the difficulty of simulating field moisture damage mechanisms. This study was carried out to investigate performance properties of crumb rubber modified asphalt concrete, using commercial warm mix asphalt technology. Commonly utilised asphalt mixtures in North America such as dense graded and stone mastic asphalt were used in this study. Uniaxial Cyclic Compression Testing (UCCT) was used to measure permanent deformation at high temperatures. Indirect Tensile Testing (IDT) was used to investigate low temperature performance. Moisture Induced Sensitivity Testing (MiST) was proposed to be an effective method for detecting the susceptibility of asphalt mixtures to moisture damage, as it incorporates major field stripping mechanisms. Sonnewarm(TM), Sasobit(TM) and Evotherm(TM) additives improved the resistance to permanent deformation of dense graded mixes at a loading rate of 0.5 percent by weight of the binder. Polymer modified mixtures showed superior resistance to permanent deformation compared to asphalt rubber in all mix types. Rediset(TM) WMX improves low temperature properties of dense graded mixes at 0.5 percent loading on the asphalt cement. Rediset LQ and Rediset WMX showed good anti stripping properties at 0.5 percent loading on the asphalt cement. The

  15. Microstructure modeling and virtual test of asphalt mixture based on three-dimensional discrete element method

    Institute of Scientific and Technical Information of China (English)

    马涛; 张德育; 张垚; 赵永利; 黄晓明

    2016-01-01

    The objective of this work is to model the microstructure of asphalt mixture and build virtual test for asphalt mixture by using Particle Flow Code in three dimensions (PFC3D) based on three-dimensional discrete element method. A randomly generating algorithm was proposed to capture the three-dimensional irregular shape of coarse aggregate. And then, modeling algorithm and method for graded aggregates were built. Based on the combination of modeling of coarse aggregates, asphalt mastic and air voids, three-dimensional virtual sample of asphalt mixture was modeled by using PFC3D. Virtual tests for penetration test of aggregate and uniaxial creep test of asphalt mixture were built and conducted by using PFC3D. By comparison of the testing results between virtual tests and actual laboratory tests, the validity of the microstructure modeling and virtual test built in this study was verified. Additionally, compared with laboratory test, the virtual test is easier to conduct and has less variability. It is proved that microstructure modeling and virtual test based on three-dimensional discrete element method is a promising way to conduct research of asphalt mixture.

  16. Validation Tests of a Non-Nuclear Combined Asphalt and Soil Density Gauge

    Science.gov (United States)

    2014-04-01

    ER D C/ G SL T R- 14 -1 0 Validation Tests of a Non-Nuclear Combined Asphalt and Soil Density Gauge G eo te ch ni ca l a nd S tr uc tu...Validation Tests of a Non-Nuclear Combined Asphalt and Soil Density Gauge Ernest S. Berney IV and Mariely Mejías-Santiago, Geotechnical and Structures...Engineer Research and Development Center in Vicksburg, MS validated the effectiveness of the Soil Density Gauge (SDG) and the Combined Asphalt Soil

  17. Test of Microstructur Permeable Asphalt Pavement Used Domato Stone (Quarsite Dolomite As Course Agregate for Surface Layer of Road Pavement

    Directory of Open Access Journals (Sweden)

    Firdaus Chairuddin

    2014-06-01

    Full Text Available The experiment works was dividing into two phases, for phase one was developed to investigate the properties of aggregates and straight asphalt qualities. The experiment work for phase two was developed to design the porous asphalt mix. In this phase Japan’s method and Binamarga’s method was used to define optimum asphalt content. In this phase, has result cantabro loss weight 77.10 for asphalt quality 3% and loss weight 9.70 for asphalt quality 5%. asphalt flow down, air void and density values. The experiment work for phase two was developed to investigate the qualities of porous asphalt. In this phase, wheel tracking machine test was used to investigate the dynamic stability of mixes.

  18. European project RE-ROAD: round robin test on extraction and recovery methods for Reclaimed Asphalts with Polymer modified Bitumens

    OpenAIRE

    MOUILLET, Virginie; PIERARD, Nathalie; Mollenhauer, Konrad; GINOUX, Marc Stéphane; Gabet, Thomas; Farcas, Fabienne; MIRSKI, Krzysztof; KEMPERLE, Ema

    2012-01-01

    The recycling of Reclaimed Asphalt (RA) in new hot-mix asphalt (HMA) is a common practice throughout Europe. However, Reclaimed Asphalts (RA) are complex materials and the use of significant proportions of RA involves a more accurate control of their characteristics. This is an essential step for asphalt mix design and a key factor to obtain good performances. At this time there is clearly a lack of knowledge and adequate test methods to analyse RA with Polymer modified Bitumens (PmBs). The p...

  19. Development of a Full-Depth Wheel Tracking Test for Asphalt Pavement Structure: Methods and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2016-01-01

    Full Text Available The rutting performance of asphalt pavement structure relies on the high temperature properties of asphalt mixture as well as the pavement structure and thickness. In order to investigate the influence of the structure and thickness, a full-depth wheel tracking test is developed in this research by improving the conventional wheel tracking test apparatus. The newly proposed test method is capable of varying its load speed and load size, controlling its specimen temperature gradient, and simulating the support conditions of actual asphalt pavement. The full-depth wheel tracking test based rutting performance evaluation of different asphalt pavement structures indicates that it is not reasonable to explain the rutting performance of asphalt pavement structure from the point of view of single-layer asphalt mixture rutting performance. The developed full-depth wheel tracking test can be used to distinguish rutting performance of different asphalt pavement structures, and two of five typical asphalt pavement structures commonly used in Shanxi Province were suggested for use in practical engineering.

  20. Testing and assessing the performance of a new warm mix asphalt with SMC

    Directory of Open Access Journals (Sweden)

    Changfa Ai

    2015-12-01

    Full Text Available Warm mix asphalt (WMA is a new technology which asphalt mix is produced and placed at normal temperature. It has advantages including low cost, environmentally friendly, haul-convenience, and so on. WMA has been widely tested and applied in the USA in the last decade, but it has just started in China. Recently, a new WMA using a new plastic-macromolecule-normal temperature additive, which was called “SMC” by the production company, was introduced as asphalt modifier. Based on discussing the strength forming process of this new WMA with SMC, a series of laboratory tests, including Marshall stability test (MST, boiling test (BT, modified immersion Marshall test (MIMT, freeze-thaw splitting test (FTST, rutting test (RT, low-temperature bending test (LTBT, and abrasion loss test (ALT, were conducted in this study to assess the performance of this WMA and the capability of applying it on low volume roads in China. SMC modified asphalt mixed under normal temperature is used in testing samples. It was found that this WMA product exhibited merits on its strength, which was about 6.7 kN bigger than the requirement of 5.0 kN in the JTG F40-2004, on high-temperature stability, which is about 1100 times/mm greater than the requirement of 600–1000 times/mm in the JTG F40-2004, and on its storage stability. Based on these indicators, it is recommended that this product could be used for low volume low class roads construction. However, due to the relatively lower water resistance and low-temperature cracking resistance, this product is suggested to be applied first in the areas with warm weather and little rainfall. In order to improve the performance of this WMA with SMC, further research on this SMC asphalt modifier should be continued.

  1. Asphalts tests using onshore drilling oil wells residues; Ensaios asfalticos utilizando residuos de perfuracao onshore

    Energy Technology Data Exchange (ETDEWEB)

    Lucena, Adriano Elisio de F.L.; Rodrigues, John Kennedy G.; Ferreira, Heber Carlos; Lucena, Leda Christiane de F.L. [Universidade Federal de Campina Grande (UFCG), PB (Brazil); Lucena, Luciana de F.L. [Faculdade de Ciencias Sociais Aplicada (FACISA), Campina Grande, PB (Brazil)

    2008-07-01

    The drilling cuttings are one of the residues produced by the oils industries in large amounts during the drilling of oil wells. An alternative of final disposal of the drilling cutting residue is its utilization in asphalt mixtures. Based on this alternative, it was realized chemical and granulometric analysis and tests (Marshall and indirect tensile strength), on the asphaltic mixture using the residue from the oil drilling wells (well: 1-POTI-4-RN, located at Governador DIX-Sept Rosado - RN - Brazil). The achieved results to Marshall test indicated that for the analyzed mixture, the ideal content of residue that can be incorporated to the asphaltic composition and attend at the DNIT-ES 31 (2006) is 5%. To the indirect tensile strength test, the results showed a strength value higher than the minimum limit requested by the DNIT (0,65 MPa). The achieved results indicated the possibility of the utilization of the drilling cuttings in asphaltic pavements as fine aggregate, obeying the percentage limits, as an alternative to the final disposal. (author)

  2. Experimental testing of hot mix asphalt mixture made of recycled aggregates.

    Science.gov (United States)

    Rafi, Muhammad Masood; Qadir, Adnan; Siddiqui, Salman Hameed

    2011-12-01

    The migration of population towards big cities generates rapid construction activities. These activities not only put pressure on natural resources but also produce construction, renovation and demolition waste. There is an urgent need to find out ways to handle this waste owing to growing environmental concerns. This can reduce pressure on natural resources as well. This paper presents the results of experimental studies which were carried out on hot mix asphalt mixture samples. These samples were manufactured by adding recycled aggregates (RA) with natural crushed stone aggregates (CSA). Three levels of addition of RA were considered in the presented studies. RA were obtained from both the concrete waste of construction, renovation and demolition activities and reclaimed asphalt pavement. Separate samples were manufactured with the coarse and fine aggregate fractions of both types of RA. Samples made with CSA were used as control specimens. The samples were prepared and tested using the Marshall method. The performance of the samples was investigated in terms of density-void and stability/flow analysis and was compared with the performance criteria as given by National Highway Authority for wearing course material in Pakistan. Based on this data optimum asphalt contents were determined. All the samples made by adding up to 50% RA conform to the specification requirements of wearing course material as given by National Highway Authority in terms of optimum asphalt contents, voids in mineral aggregates and stability/flow. A statistical analysis of variation of these samples confirmed that addition is also possible statistically.

  3. Development of a Full-Depth Wheel Tracking Test for Asphalt Pavement Structure: Methods and Performance Evaluation

    OpenAIRE

    Hui Wang; Zepeng Fan; Jiupeng Zhang

    2016-01-01

    The rutting performance of asphalt pavement structure relies on the high temperature properties of asphalt mixture as well as the pavement structure and thickness. In order to investigate the influence of the structure and thickness, a full-depth wheel tracking test is developed in this research by improving the conventional wheel tracking test apparatus. The newly proposed test method is capable of varying its load speed and load size, controlling its specimen temperature gradient, and simul...

  4. Laboratory evaluation of selected tar sand asphalts

    Energy Technology Data Exchange (ETDEWEB)

    Button, J.W.; Epps, J.A.; Gallaway, B.M.

    1980-12-01

    Three tar sand asphalts of similar grades prepared from one syncrude by three different refining methods were characterized by tests commonly used to specify paving asphalts together with certain special tests. Asphalt-aggregate mixtures were prepared using these asphalts and tested in the laboratory to determine strength stiffness stability, tensile properties, temperature effects and water susceptibility. Comparison of the tar sand asphalt properties to conventional petroleum asphalt properties reveal no striking differences.

  5. Certification Tests on Cold Patch Asphalt Repair Materials for Use in Airfield Pavements

    Science.gov (United States)

    2010-06-01

    was then applied for 60 sec to the specimens, and the deviator stress of 90 psi was applied. The test was terminated when 4% strain was reached or... pavements . ERDC-GSL TR-05-07. Vicksburg, MS: U.S. Army Engineer Research and Development Center. U.S. Air Force. 2008a. Testing protocol for rigid spall...ER D C/ G SL T R- 10 -1 4 Certification Tests on Cold Patch Asphalt Repair Materials for Use in Airfield Pavements G eo te ch ni

  6. Full-Depth Pavement Reclamation with Foamed Asphalt: First-Level Analysis Report on HVS Testing on State Route 89

    OpenAIRE

    Theyse, Hecter; Long, Fenella; Jones, David; Harvey, John T

    2006-01-01

    This report focuses on the HVS testing of a foamed asphalt treated, reclaimed asphalt pavement (RAP) on State Route 89 near Sierraville. The report discusses the expected behavior of the HVS test sections, presents the results from field surveys done during June 2003, October 2003 and May 2004 as well as the 1st level analysis of HVS results from the test site. Results from field surveys done prior to, during and after HVS testing show that the pavement structure of the HVS test sections on S...

  7. Sensitivity of some asphalts to the wheel tracking test

    OpenAIRE

    Dubois, Vincent; DE LA ROCHE, Chantal; Buisson, Sébastien

    2008-01-01

    In the framework of LCPC fatigue carrousel studies [Corté and others, 1994; Gramsammer and others, 1994], rutting measurements on several mixes have been carried out. For each mix, the granular distribution has been identical, but different types of bitumen have been chosen : classical bitumen 50/70, EVA modified bitumen and SBS modified bitumen. These mixes have been designed by a previous laboratory tests campaign. In comparing field and laboratory results, a different behaviour is observed...

  8. 硬质沥青及其混合料高温性能试验研究%Research on Test for High-temperature Performance of Hard Asphalt and Hard Asphalt Mixture

    Institute of Scientific and Technical Information of China (English)

    杨志勇; 黄拓; 肖畅

    2011-01-01

    Through DSR tesl lo A-30 hard asphalt and A-70 asphalt, the high-temperature performance of A-30 hard asphalt was analyzed; through single axle creep test and rutting test to four kinds of asphalt mixture, the high-temperature performance of A-30 hard asphalt mixture was analyzed. From that we can draw a conclusion that the hard asphalt mixture which can enhance the high temperature stability of pavement structure is suitable for the paving of base layer.%本文对硬质沥青(A-30)和目前沥青路面常用的重交沥青(A-70)进行了DSR试验,对比分析了30号硬质沥青的高温性能;对四种沥青混合料进行单轴蠕变试验和车辙试验,分析了30号硬质沥青混合料的高温性能.试验结果表明:硬质沥青混合料可提高路面结构的高温稳定性,适用于基层铺装.

  9. A methodology for use of digital image correlation for hot mix asphalt testing

    Science.gov (United States)

    Ramos, Estefany

    Digital Image Correlation (DIC) is a relatively new technology which aids in the measurement of material properties without the need for installation of sensors. DIC is a noncontact measuring technique that requires the specimen to be marked with a random speckled pattern and to be photographed during the test. The photographs are then post-processed based on the location of the pattern throughout the test. DIC can aid in calculating properties that would otherwise be too difficult even with other measuring instruments. The objective of this thesis is to discuss the methodology and validate the use of DIC in different hot mix asphalt (HMA) tests, such as, the Overlay Tester (OT) Test, Indirect Tensile (IDT) Test, and the Semicircular Bending (SCB) Test. The DIC system provides displacements and strains in any visible surface. The properly calibrated 2-D or 3-D DIC data can be used to understand the complex stress and strain distributions and the modes of the initiation and propagation of cracks. The use of this observational method will lead to further understanding of the complex boundary conditions of the different test, and therefore, allowing it to be implemented in the analysis of other materials. The use of digital image correlation will bring insight and knowledge onto what is happening during a test.

  10. Asphalt Mixture for the First Asphalt Concrete Directly Fastened Track in Korea

    Directory of Open Access Journals (Sweden)

    Seong-Hyeok Lee

    2015-01-01

    Full Text Available The research has been initiated to develop the asphalt mixtures which are suitable for the surface of asphalt concrete directly fastened track (ADFT system and evaluate the performance of the asphalt mixture. Three aggregate gradations which are upper (finer, medium, and below (coarser. The nominal maximum aggregate size of asphalt mixture was 10 mm. Asphalt mixture design was conducted at 3 percent air voids using Marshall mix design method. To make impermeable asphalt mixture surface, the laboratory permeability test was conducted for asphalt mixtures of three different aggregate gradations using asphalt mixture permeability tester. Moisture susceptibility test was conducted based on AASHTO T 283. The stripping percentage of asphalt mixtures was measured using a digital camera and analyzed based on image analysis techniques. Based on the limited research results, the finer aggregate gradation is the most suitable for asphalt mixture for ADFT system with the high TSR value and the low stripping percentage and permeable coefficient. Flow number and beam fatigue tests for finer aggregate asphalt mixture were conducted to characterize the performance of asphalt mixtures containing two modified asphalt binders: STE-10 which is styrene-butadiene-styrene (SBS polymer and ARMA which is Crum rubber modified asphalt. The performance tests indicate that the STE-10 shows the higher rutting life and fatigue life.

  11. 短切沥青碳纤维混凝土马歇尔试验研究%Marshall test research on chopped asphalt carbon fiber concrete

    Institute of Scientific and Technical Information of China (English)

    张明德

    2012-01-01

    The paper discusses the impact of chopped asphalt carbon fiber on asphalt concrete,compares the changing situation of various indicators of Marshall test,and determines the mixing proportion of chopped asphalt carbon fiber concrete,which has provided certain basis for the construction and design of chopped asphalt carbon fiber concrete.%讨论了短切沥青碳纤维对沥青混凝土马歇尔试验的影响,比较了马歇尔试验各项技术指标的变化情况,确定了短切沥青碳纤维混凝土的配比,为指导短切沥青碳纤维混凝土的设计和施工提供依据。

  12. 沥青路面渗水性能测试研究%Study on Permeability Test of Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    但汉成; 李亮; 何要超; 赵炼恒; 王峰

    2009-01-01

    In order to study the permeability of pavement, an improved method for testing the infiltration coefficient of pavement was adopted into a section of expressway under construction in Hunan province. According to the test result and with combination of the evaluation method, the permeability of each surface course in asphalt pavement was evaluated and analyzed. The differences of permeability of different asphalt mixtures for asphalt pavement were obtained. On this basis, the suggested guidelines of different maximum nominal sizes of aggregate for asphalt pavement permeability test were put forward. Finally, the differences of permeability of different surface courses were analyzed qualitatively. The result shows that (1) the permeabilities of different surface courses exhibit a great variability and coarse aggregate asphalt mixture infiltrates easily than medium aggregate asphalt mixture; (2) the permeability of coarse aggregate asphalt mixture which is incorporated with anti-rut agent will decrease slightly; (3) the permeability coefficient increases with the increasing of thickness of surface course; (4) the transverse distribution of infiltration coefficient on pavement is non-uniform which results from the construction variability and the infiltration coefficient of passing lane is higher than that of driving lane.%采用改进的渗水系数测试试验对湖南省在建高速公路沥青路面进行渗水系数测试.根据测试结果结合沥青路面渗水性能的评价方法对沥青路面各面层的渗水性能进行评价分析,得出了沥青路面不同沥青混合料类型的渗水性能差异,提出了沥青混合料不同公称最大粒径的沥青混合料路面检验用的建议指标.最后对路面结构层的透水性能的差异性进行了定性分析,分析表明:沥青路面各面层的渗水性表现出很大的变异性;粗粒式沥青混合料类型更易渗水;粗粒式沥青混合料掺入抗车辙剂其渗水性能会有所降低;

  13. Evaluation on Low Temperature Performance of Recycled Asphalt Mixture Using Warm Mix Asphalt Technology

    Directory of Open Access Journals (Sweden)

    Xiaolan Duan,

    2015-04-01

    Full Text Available In this paper, the basic idea is about the recycled technology of asphalt mixture, more in-depth study of the lowtemperature performance of warm mix asphalt(WMA.First of all, Including the evaluation of low temperature performance of WMA made of reclaimed asphalt pavement (RAP (passed and not passed 2.36mm screen, and the influence of WMA with RAP mixed of different dosage of dispersant. Then, using the SBS modified asphalt and base asphalt were test at low temperature, research on the influence of different type of asphalt to the low temperature performance of WMA.

  14. Strength Mechanism and Influence Factors for Cold Recycled Asphalt Mixture

    OpenAIRE

    Tao Ma; Hao Wang; Yongli Zhao; Xiaoming Huang; Yuhui Pi

    2015-01-01

    This study focused on the key factors affecting the tensile strength of cold recycled asphalt mixture with cement and emulsified asphalt. The specific surface areas and strength of RAP were analyzed. The interaction between the emulsified asphalt and cement was observed. Comprehensive laboratory testing was conducted to evaluate the influences of RAP, emulsified asphalt, and cement on the tensile strength of cold recycled asphalt mixture. It is found that although RAP is used as aggregates, i...

  15. Dynamic Modulus Test Analysis of Sulfur Modified Asphalt Mixture%硫磺改性沥青混合料的动态模量试验分析

    Institute of Scientific and Technical Information of China (English)

    侯睿; 郭忠印

    2013-01-01

    UTM system was used to test asphalt mixture's dynamic modulus with different sulfur contents (by mass).The influences of temperature,loading frequency and sulfur content on the viscoelastic properties of asphalt mixtures were analyzed.The results show that the temperature and loading frequency have the same influence on dynamic modulus of both sulfur modified asphalt mixture and conventional asphalt mixture.The effect of sulfur contents on viscoelastic properties of asphalt mixtures is different.A small quantity of sulfur will increase asphalt mixture's viscosity and temperature sensitivity,but a large quantity of sulfur will increase asphalt mixture's elasticity and reduce temperature sensitivity.%采用UTM系统对不同硫磺掺量(质量比)的沥青混合料进行动态模量试验,分析了温度、加载频率和硫磺掺量对沥青混合料黏弹特性的影响.结果表明:温度和加载频率对硫磺改性沥青混合料和普通沥青混合料动态模量的影响规律基本相同;不同硫磺掺量对沥青混合料黏弹性能的影响有所不同,硫磺掺量较小时,沥青混合料的黏性增加,温度敏感性增大;硫磺掺量较大时,沥青混合料的弹性增加,温度敏感性降低.

  16. Evotherm温拌沥青混合料性能试验研究%Test Research on Evotherm Warm Mix Asphalt Performance

    Institute of Scientific and Technical Information of China (English)

    刘永贵; 凌剑兴; 张继森; 吴超凡

    2013-01-01

    研究了Evotherm温拌SBS改性沥青,结果表明,Evotherm温拌剂对SBS改性沥青性能影响不大.采用旋转压实和马歇尔击实对Evotherm温拌SBS改性沥青混合料性能进行研究,研究结果表明,Evotherm温拌SBS改性沥青混合料碾压温度可较热拌沥青混合料降低20℃~30℃左右.温拌混合料的水稳性能较热拌沥青混合料有所提升,浸水马歇尔残留稳定度从93.5%提高到95.2%,冻融劈裂试验强度比从83.8%提高到86.4%;高温稳定性能有所提升,车辙试验动稳定度从7 314次/mm提高到8 023次/mm;低温抗裂性能变化不大.总体来说,击实温度145℃的温拌沥青混合料性能优于热拌沥青混合料.%This paper research the Evotherm SBS modified asphalt, the results show that, Evo-therm has little Influence on SBS modified asphalt. Using rotary compaction and Marshall compaction to research characteristic of Evotherm warm mix asphalt. Research results show that, Evotherm warm mix asphalt compaction temperature can reduce 20 ~ 30 ℃ compared with hot mix asphalt. Warm mix asphalt water stability was improved compared with hot mix asphalt, Marshall immersion residual stability increased from 93. 5% to 95. 2% , freeze-thaw splitting test intensity ratio increased from 83. 8% to 86. 4% ; high temperature stability performance has the promotion, rutting test dynamic stability from 7 314 time/mm to 8 023 time/mm; low temperature resistance performance changed little. Over all, Performance of warm mixed asphalt compacted in 145 t is better than that of hot mix asphalt.

  17. Rheological characteristics of aged asphalt binder

    Institute of Scientific and Technical Information of China (English)

    刘聪慧; 吴少鹏; 刘全涛; 朱国军

    2008-01-01

    Different aging levels(RTFOT,PAV-10h,PAV-20h and PAV-30 h) of asphalt binders with various mass ratios of mineral powder to asphalt(0,0.4,0.8,1.2,1.6,2.0) were used to investigate the rheological properties of aged asphalt binders with respect to their short and long terms aging characteristics.Viscosity test,dynamic shear test and creep test were conducted.The test results indicate that the viscosity of aged asphalt binder increases sharply with the extension of aging period.Complex shear modulus of aged asphalt increases,which indicates that the stiffness of asphalt binders can increase.The phase angle for aged asphalt binders reduces,which indicates that the elastic portion for viscoelastic property of asphalt binders increases.|G*|·sin δ increases after aging procedure which means that the fatigue resistance becomes poor.The creep test results show that creep strain curves varies remarkably for virgin and aged asphalt binders.The total strain during loading period and the permanent strain decreases significantly for aged asphalt binders,which implies that the elastic portion increases and the viscous portion decreases.

  18. The Asphalt Handbook.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    The new and completely revised edition of the Asphalt Handbook, a standard reference work in the field of asphalt technology and construction, summarizes with reference the information contained in other Asphalt Institute technical manuals. Major areas discussed include the following--(1) uses of asphalt, (2) terms relating to asphalt and its…

  19. Testing of asphalt mixture thermal conductivity and its influences on asphalt pavement temperature field%沥青路面导热系数测试及其对路面温度场影响的模拟

    Institute of Scientific and Technical Information of China (English)

    李彦伟; 张倩; 谢来斌; 何勇海; 刘建

    2012-01-01

    沥青路面温度场是沥青路面车辙计算和沥青混合料粘弹性分析的重要参数,路面温度场的精确预估涉及到面层各层材料热物理参数的精确测试,因此沥青混合料热物理参数的准确测试变得越来越重要.基于对测试结果重现性和可比性的考虑,采用瞬态热线法进行沥青混合料导热系数的测试,选取几种有代表性的混合料进行了导热系数测试,分析了影响导热系数的因素.基于ABAQUS模拟计算路面温度场分布,通过改变路面上、中、下面层的导热系数,计算路面温度场分布变化的情形,对计算结果的分析发现,上面层导热系数对面层温度场分布的影响更显著,可以预期通过改变上面层导热系数能达到主动改善沥青路面工作温度的目的.%Accurate temperature field estimation is crucial to asphalt mixture's visco-elastic analysis and rutting depth calculation. Temperature filed estimation is closely related to pavement layers' thermal physical parameters. Therefore, precise testing of asphalt mixture physical parameters becomes more and more important. A-mong the thermal physical parameters, testing of thermal conductivity is given special attention because it's one of the most commonly used parameters of asphalt mixture. Hot wire method is considered a suitable method in testing HMA thermal conductivity coefficient and its testing principle is introduced. Thermal conductivities of four types of asphalt mixtures with different gradation are tested using transient hot wire method. And its influencing factors are analyzed. An asphalt pavement structure is modeled and its temperature field distribution was calculated using finite element software ABAQUS. Based on the calculation, it is found that asphalt pavement temperature field distributioVi changes with the change of thermal conductivities of the top layer, mid layer and bottom layer. It can be seen from the simulation result that thermal

  20. The test and application research on new road maintenance material“asphalt recycling”%新型道路养护材料“沥再生”的试验及应用研究

    Institute of Scientific and Technical Information of China (English)

    尹亮

    2014-01-01

    Based on the test research on asphalt recycling materials,this paper tested the activation and regeneration effect of asphalt recycling to aging asphalt,explored the relationship between asphalt recycling mixing amount and recycling effect,verified the feasibility applied asphalt re-cycling to asphalt pavement maintenance,and through the comprehensive analysis on detection data to asphalt recycling test section of Weitong highway,gained the asphalt recycling was a good material for road maintenance.%在对沥再生材料进行试验研究的基础上,检验了沥再生对老化沥青的激活再生效果,探讨了沥再生掺量与再生效果之间的关系,验证了沥再生应用于沥青路面养护的可行性,并通过对渭潼高速公路沥再生试验段的检测数据进行综合分析,得出沥再生是一种良好的道路养护材料。

  1. Interaction nonlinearity in asphalt binders

    Science.gov (United States)

    Motamed, Arash; Bhasin, Amit; Liechti, Kenneth M.

    2012-05-01

    Asphalt mixtures are complex composites that comprise aggregate, asphalt binder, and air. Several research studies have shown that the mechanical behavior of the asphalt mixture is strongly influenced by the matrix, i.e. the asphalt binder. Characterization and a thorough understanding of the binder behavior is the first and crucial step towards developing an accurate constitutive model for the composite. Accurate constitutive models for the constituent materials are critical to ensure accurate performance predictions at a material and structural level using micromechanics. This paper presents the findings from a systematic investigation into the nature of the linear and nonlinear response of asphalt binders subjected to different types of loading using the Dynamic Shear Rheometer (DSR). Laboratory test data show that a compressive normal force is generated in an axially constrained specimen subjected to torsional shear. This paper investigates the source of this normal force and demonstrates that the asphalt binder can dilate when subjected to shear loads. This paper also presents the findings from a study conducted to investigate the source of the nonlinearity in the asphalt binder. Test results demonstrate that the application of cyclic shear loads results in the development of a normal force and a concomitant reduction in the dynamic shear modulus. This form of nonlinear response is referred to as an "interaction nonlinearity". A combination of experimental and analytical tools is used to demonstrate and verify the presence of this interaction nonlinearity in asphalt binders. The findings from this study highlight the importance of modeling the mechanical behavior of asphalt binders based on the overall stress state of the material.

  2. Evaluation on Low Temperature Performance of Recycled Asphalt Mixture Using Warm Mix Asphalt Technology

    OpenAIRE

    Xiaolan Duan,; Chunge Li

    2015-01-01

    In this paper, the basic idea is about the recycled technology of asphalt mixture, more in-depth study of the lowtemperature performance of warm mix asphalt(WMA).First of all, Including the evaluation of low temperature performance of WMA made of reclaimed asphalt pavement (RAP) (passed and not passed 2.36mm screen), and the influence of WMA with RAP mixed of different dosage of dispersant. Then, using the SBS modified asphalt and base asphalt were test at low temperature, researc...

  3. Asphalt cement poisoning

    Science.gov (United States)

    ... petroleum material that hardens when it cools. Asphalt cement poisoning occurs when someone swallows asphalt. If hot ... found in: Road paving materials Roofing materials Tile cements Asphalt may also be used for other purposes.

  4. Sustainable asphalt pavement: Application of slaughterhouse waste oil and fly ash in asphalt binder

    Science.gov (United States)

    Sanchez Ramos, Jorge Luis

    Increasing energy costs, lack of sufficient natural resources and the overwhelming demand for petroleum has stimulated the development of alternative binders to modify or replace petroleum-based asphalt binders. In the United States, the petroleum-based asphalt binder is mainly used to produce the Hot Mix Asphalt (HMA). There are approximately 4000 asphalt plants that make 500 million tons of asphalt binder valued at roughly 3 billion/year. The instability of the world's oil market has pushed oil prices to more than 80 per barrel in 2012, which increased the cost of asphalt binder up to $570 per ton. Therefore, there is a timely need to find alternative sustainable resources to the asphalt binder. This paper investigates the possibility of the partial replacement of the asphalt binder with slaughterhouse waste and/or fly ash. In order to achieve this objective, the asphalt binder is mixed with different percentages of waste oil and/or fly ash. In order to investigate the effect of these additives to the performance of the asphalt binder, a complete performance grade test performed on multiple samples. The results of the performance grade tests are compared with a control sample to observe how the addition of the waste oil and/or fly ash affects the sample. Considering the increasing cost and demand of asphalt, the use of slaughterhouse waste oil and/or fly ash as a partial replacement may result in environmental and monetary improvements in the transportation sector.

  5. Permeability Test of Asphalt Pavement and countermeasures%沥青路面渗水试验检测与防治对策

    Institute of Scientific and Technical Information of China (English)

    李伟

    2015-01-01

    〗沥青路面渗水的原因主要包括水力冲刷、置换作用等。工程运营前要严格按照规范要求进行渗水试验,计算并整理渗水系数。同时还要合理选择面层结构、重视施工质量控制、提高沥青与集料的结合性能、改善排水设施,对渗水路面也要及时采取措施处理。从而实现对渗水现象的有效预防,确保沥青路面工程质量。%The reasons of asphalt pavement seepage mainly include the hydraulic erosion and replace-ment effect.Before the engineering operations,asphalt pavement should be strictly tested in accord-ance with the requirements of the specification of Permeability test.It is necessary to select the struc-ture of the surface,pay attention to the construction quality control,improve the combination of as-phalt and aggregate,improve the drainage facilities,as well as the seepage pavement,so as to realize the effective prevention of the seepage phenomenon and ensure the quality of asphalt pavement engi-neering.

  6. Characterization of hot-mix asphalt concrete containing municipal solid waste incinerator ash using the dynamic modulus (E) test

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, H.F. [Sultan Qaboos Univ., Muscat (Oman). College of Engineering

    2007-07-01

    In 2001, approximately 229 million tons of municipal solid waste (MSW) were produced in the United States. MSW consists of items such as paper, grass clippings, furniture, clothing, bottles, food scraps, appliances, paint, and batteries. MSW incinerator ash is the by-product produced during the combustion of municipal solid waste in combustor facilities and has two components, namely bottom ash and fly ash. To reduce the disposal problem, the incinerators are used to reduce the volume and weight of MSW. This is usually a self-sustained process using the waste as a fuel resulting in as much as a 90 and 75 per cent reduction in volume and weight, respectively. This paper presented the results of a study that investigated the use of incinerator ash as a partial replacement of fine aggregate in hot-mix asphalt concrete. MSW incinerator ash was collected from an incinerator facility at Sultan Qaboos University in Oman and a physical and chemical characterization of the ash was conducted. MSW ash was used in the mixture to replace fine aggregate with a percentage ranging from 0 to 40 per cent, by total aggregate weight. The mixes were designed using the Marshall mix design method and the dynamic modulus test was conducted on samples prepared at optimum asphalt contents for mixes containing different percentage of ash and at different temperatures and frequencies. Master curves for different percentages of ash in the mix were developed from the testing results. It was found that the Marshall mix design results for the mixes containing MSW ash indicated a decrease in stability, and specific gravity, and an increase in air voids. 18 refs., 10 figs.

  7. Asphalt World

    OpenAIRE

    Bedwell, Simon A.

    2009-01-01

    'What, in the end, makes advertisement so superior to criticism? Not what the moving red neon sign says - but the fiery pool reflecting it in the asphalt.' Benjamin, One-Way Street 'The parade has nothing to do with women, everything to do with men... Women are simply the scenery onto which men project their narcissistic fantasies.' Mulvey, Visual & Other Pleasures With invested irony, Simon Bedwell makes drip paintings from used advertising posters, in a messy conflation of a...

  8. Performance Test of Rubber Asphalt and Analysis of Influencing Factors%橡胶沥青性能试验及影响因素分析

    Institute of Scientific and Technical Information of China (English)

    刘子兴; 常立峰

    2011-01-01

    Aiming at road performance of rubber asphalt and influencing factors, this paper studies influences of types of rubber powder, content of rubber powder, types of base asphalt and mixing temperature, etc. on high-temperature, low-temperature and ageing resistant properties, etc. of rubber asphalt via indoor test. The test result shows that the high-temperature, low-temperature and fatigue resisting properties of asphalt have been improved to some degree after addition of rubber powder. Among them high-temperature property of modified asphalt with 20-mesh rubber powder is better than that of modified asphalt with 40-mesh and 60-mesh rubber powders, and the low-temperature and fatigue resisting properties of all three rubber powders are relatively approximate. For CNOOC (Taizhou) AH-70 base asphalt, when 20-mesh rubber powder for truck tires is adopted for modification, the optimal dosage is 16% ~18%.%针对橡胶沥青的路用性能及其影响因素,通过室内试验研究胶粉类型、胶粉掺量、基质沥青类型、拌和温度等对橡胶沥青高温、低温和抗老化性能等的影响.试验结果表明:添加胶粉后,沥青的高温、低温及抗疲劳性能均有不同程度的改善.其中,20目胶粉改性沥青的高温性能优于40和60目胶粉改性沥青,三者低温以及抗疲劳性能则比较接近;对于中海油(泰州)AH-70基质沥青而言,当采用20目货车轮胎胶粉改性时,最佳掺量为16%~18%.

  9. 岩沥青混合料高温性能的车辙对比试验分析%Evaluation of the High-temperature Stability of Rock Asphalt Mixture by Rutting Contrast Test

    Institute of Scientific and Technical Information of China (English)

    孙宗元; 李冬雪

    2011-01-01

    In this paper, a series of rutting tests of the asphalt mixtures with different types and contents of rock asphalt based asphalt 70# were made at high temperature. Based on the results of three kinds of rutting tests, the experiments indicated that the stability of the rock asphalt mixtures at high temperature was markedly increased. They also showed that it was more important to choose high quality rock asphalt than to use high-content rock asphalt. All of these conclusions were helpful to the use of rock asphalt.%本文以70沥青作为基质沥青,对不同种类和掺量的岩沥青改性沥青的高温抗车辙能力进行了研究.基于三种车辙试验的试验结果表明,随着岩沥青掺量的增加,改性沥青的高温抗车辙能力得到提高.同时,得出选用优质的岩沥青种类比无谓的掺入大量的岩沥青更重要的结论,从而为岩沥青的应用提供了参考.

  10. Seismic joint analysis for non-destructive testing of asphalt and concrete slabs

    Science.gov (United States)

    Ryden, N.; Park, C.B.

    2005-01-01

    A seismic approach is used to estimate the thickness and elastic stiffness constants of asphalt or concrete slabs. The overall concept of the approach utilizes the robustness of the multichannel seismic method. A multichannel-equivalent data set is compiled from multiple time series recorded from multiple hammer impacts at progressively different offsets from a fixed receiver. This multichannel simulation with one receiver (MSOR) replaces the true multichannel recording in a cost-effective and convenient manner. A recorded data set is first processed to evaluate the shear wave velocity through a wave field transformation, normally used in the multichannel analysis of surface waves (MASW) method, followed by a Lambwave inversion. Then, the same data set is used to evaluate compression wave velocity from a combined processing of the first-arrival picking and a linear regression. Finally, the amplitude spectra of the time series are used to evaluate the thickness by following the concepts utilized in the Impact Echo (IE) method. Due to the powerful signal extraction capabilities ensured by the multichannel processing schemes used, the entire procedure for all three evaluations can be fully automated and results can be obtained directly in the field. A field data set is used to demonstrate the proposed approach.

  11. Strength Mechanism and Influence Factors for Cold Recycled Asphalt Mixture

    Directory of Open Access Journals (Sweden)

    Tao Ma

    2015-01-01

    Full Text Available This study focused on the key factors affecting the tensile strength of cold recycled asphalt mixture with cement and emulsified asphalt. The specific surface areas and strength of RAP were analyzed. The interaction between the emulsified asphalt and cement was observed. Comprehensive laboratory testing was conducted to evaluate the influences of RAP, emulsified asphalt, and cement on the tensile strength of cold recycled asphalt mixture. It is found that although RAP is used as aggregates, its inner structure and strength are much different from real aggregates. The strength of RAP has decisive effect on the strength of cold recycled asphalt mixture. New aggregates and fine gradation design can help improve the bonding between RAP and binder. For emulsified asphalt, slow setting of asphalt can give sufficient time for cement to hydrate which is helpful for strength formation in the cold recycled asphalt mixture. The high viscosity of asphalt can improve the early strength of cold recycled asphalt mixture that is important for traffic opening in the field. Cement is an efficient additive to improve the strength of cold recycled asphalt mixtures by promoting demulsification of emulsified asphalt and producing cement hydrates. However, the cement content is limited by RAP.

  12. Fatigue behavior of asphalt mixtures colombian with addition recycled pavement asphalt to 100 %

    Directory of Open Access Journals (Sweden)

    Neidy Betssey Patiño Boyacá

    2015-01-01

    Full Text Available This research was conducted in order to establish the fatigue behavior of asphalt mixtures with gradations MD20 Instituto de Desarrollo Urbano (IDU and MDC 2 of The Instituto Nacional de Vías (INVIAS, with addition of recycled granular flexible pavement (RAP with asphalt of penetration 60/70 and 80/100. The first step was to characterize the asphalt and RAP as well as calculate the optimum percentage of asphalt to be added to 100 % RAP mixtures. Then samples were fabricated with different trapezoidal gradations and asphalt, to be tested finally fatigue at different deformations. Among the results found, it was determined that the tested mixtures have a high stiffness; although, it varies depending on the asphalt mix used and that the best fatigue life with respect to those studied is the MDC-2 with bitumen 80/100.

  13. Evaluation of the Permanent Deformations and Aging Conditions of Batu Pahat Soft Clay-Modified Asphalt Mixture by Using a Dynamic Creep Test

    Directory of Open Access Journals (Sweden)

    Al Allam A. M.

    2016-01-01

    Full Text Available This study aimed to evaluate the permanent deformation and aging conditions of BatuPahat soft clay–modified asphalt mixture, also called BatuPahat soft clay (BPSC particles; these particles are used in powder form as an additive to hot-mix asphalt mixture. In this experiment, five percentage compositions of BPSC (0%, 2%, 4%, 6%, and 8% by weight of bitumen were used. A novel design was established to modify the hot-mix asphalt by using the Superpave method for each additive ratio. Several laboratory tests evaluating different properties, such as indirect tensile strength, resilient stiffness modulus, and dynamic creep, was conducted to assess the performance of the samples mixed through the Superpave method. In the resilient modulus test, fatigue and rutting resistance were reduced by the BPSC particles. The added BPSC particles increased the indirect tensile strength. Among the mixtures, 4% BPSC particles yielded the highest performance. In the dynamic creep test, 4% BPSC particles added to the unaged and short-term aged specimens also showed the highest performance. Based on these results, our conclusion is that the BPSC particles can alleviate the permanent deformation (rutting of roads.

  14. Behaviour of asphalt rubber mixtures with different crumb rubber and asphalt binder sources

    OpenAIRE

    Fontes, Liseane P. T. L.; Pereira, Paulo A. A.; Pais, Jorge C.; Trichês, Glicério

    2006-01-01

    This study evaluates the performance in laboratory of gap graded mixture prepared with different crumb rubber types and different conventional grade asphalt binders. The asphalt rubbers were prepared via wet process (continuous blend) and their properties were measured through the current tests: (i) penetration;(ii) softening point: (iii) resilience; (iv) apparent viscosity using a Brookfield viscometer. The rheological properties for conventional asphalts were measured too, in order to evalu...

  15. Linking asphalt binder fatigue to asphalt mixture fatigue performance using viscoelastic continuum damage modeling

    Science.gov (United States)

    Safaei, Farinaz; Castorena, Cassie; Kim, Y. Richard

    2016-08-01

    Fatigue cracking is a major form of distress in asphalt pavements. Asphalt binder is the weakest asphalt concrete constituent and, thus, plays a critical role in determining the fatigue resistance of pavements. Therefore, the ability to characterize and model the inherent fatigue performance of an asphalt binder is a necessary first step to design mixtures and pavements that are not susceptible to premature fatigue failure. The simplified viscoelastic continuum damage (S-VECD) model has been used successfully by researchers to predict the damage evolution in asphalt mixtures for various traffic and climatic conditions using limited uniaxial test data. In this study, the S-VECD model, developed for asphalt mixtures, is adapted for asphalt binders tested under cyclic torsion in a dynamic shear rheometer. Derivation of the model framework is presented. The model is verified by producing damage characteristic curves that are both temperature- and loading history-independent based on time sweep tests, given that the effects of plasticity and adhesion loss on the material behavior are minimal. The applicability of the S-VECD model to the accelerated loading that is inherent of the linear amplitude sweep test is demonstrated, which reveals reasonable performance predictions, but with some loss in accuracy compared to time sweep tests due to the confounding effects of nonlinearity imposed by the high strain amplitudes included in the test. The asphalt binder S-VECD model is validated through comparisons to asphalt mixture S-VECD model results derived from cyclic direct tension tests and Accelerated Loading Facility performance tests. The results demonstrate good agreement between the asphalt binder and mixture test results and pavement performance, indicating that the developed model framework is able to capture the asphalt binder's contribution to mixture fatigue and pavement fatigue cracking performance.

  16. Curing Reaction Model of Epoxy Asphalt Binder

    Institute of Scientific and Technical Information of China (English)

    QIAN Zhendong; CHEN Leilei; WANG Yaqi; SHEN Jialin

    2012-01-01

    In order to understand the strength developing law of the epoxy asphalt mixture,a curing reaction model of the epoxy asphalt binder was proposed based upon the thermokinetic analysis.Given some assumptions,the model was developed by applying the Kissinger law as well as Arrhenius equation,and the differential scanning calorimetry was performed for estimating the model parameters.To monitor the strength development of the epoxy asphalt mixture,a strength test program was employed and then results were compared to those produced from the proposed model.The comparative evaluation shows that a good consistency exists between the outputs from test program and the proposed model,indicating that the proposed model can be used effectively for simulating the curing reaction process for the epoxy asphalt binder and predicting the strength development for the epoxy asphalt mixture.

  17. Asbestos Tailings as Aggregates for Asphalt Mixture

    Institute of Scientific and Technical Information of China (English)

    LIU Xinoming; XU Linrong

    2011-01-01

    To use many asbestos tailings collected in Ya-Lu highway, and to explore the feasibility of using asbestos tailings as aggregates in common asphalt mixtures, and properties of some asphalt mixtures were evaluated as well. X-ray diffraction (XRD), X-ray fluorescent (XRF), and atomic absorption spectrophotometry (AAS) were employed to determine the solid waste content of copper, zinc, lead, and cadmium. Volume properties and pavement performances of AC-25 asphalt mixture with asbestos tailings were also evaluated compared with those with basalt as aggregates.XRD and XRF measurement results infer that asbestos tailing is an excellent road material. Volume properties of AC-25 asphalt mixture with asbestos tailings satisfied the related specifications. No heavy metals and toxic pollution were detected in AAS test and the value of pH test is 8.23, which is help to the adhesion with asphalt in the asphalt concrete. When compared with basalt, high temperature property and the resistance to low temperature cracking of AC-25 asphalt mixture was improved by using asbestos tailings as aggregates. In-service AC-25 asphalt pavement with asbestos tailings also presented excellent performance and British Pendulum Number (BPN) coefficient of surface.

  18. Rheological Evaluation of Polymer Modiifed Asphalt Binders

    Institute of Scientific and Technical Information of China (English)

    WANG Lan; CHANG Chunqing

    2015-01-01

    The microstructure and dynamic rheological characteristics of asphalt containing different polymer modifiers (crumb rubber, styrene-butadiene-styrene and crumb rubber mix with styrene-butadiene-styrene) at mid and high service temperature levels were investigated by using scanning electron microscopy(SEM), dynamic shear rheometer(DSR) and repeat creep test. The main objective of the investigation was to rank the modifiers based on their effect on performance characteristics of asphalt under service conditions. To evaluate the effect of different modiifers on the viscoelastic response of asphalt, the temperature and frequency dependences of the dynamic viscoelastic properties were compared. The mid-temperature fatigue resistance and high-temperature rutting resistance of three polymer modiifed asphalts were evaluated to predict their ifeld performance in roads. Based on the current results, an improved rutting factor was proposed to determine the rutting resistance of asphalt pavements. In addition, the viscous stiffness (Gv), deifned as the reciprocal of viscous compliance, was used to evaluate the high-temperature deformation resistance of asphalt mixtures. The experimental results indicate that the asphalt containing crumb rubber only shows superior performance at mid and high service temperatures in all three modiifed asphalt binders due to the action of the crumb rubber.

  19. Low temperature asphalt mixtures

    OpenAIRE

    Modrijan, Damjan

    2006-01-01

    This thesis presents the problem of manufacturing and building in the asphalt mixtures produced by the classical hot procedure and the possibility of manufacturing low temperature asphalt mixtures.We will see the main advantages of low temperature asphalt mixtures prepared with bitumen with organic addition Sasobit and compare it to the classical asphalt mixtures. The advantages and disadvantages of that are valued in the practical example in the conclusion.

  20. Porous Flame-retarded Asphalt Pavement for Highway Tunnel

    Institute of Scientific and Technical Information of China (English)

    HU Shuguang; HUANG Shaolong; Ding Qingjun

    2008-01-01

    A new way to improve the tunnel fire protection by using flame-retarded porous asphalt pavement containing ATH powders was introduced. Based on the miniature burning test designed and conducted, the burning time and temperature of porous asphalt (PA) and flame-retarded porous asphalt (FRPA) were studied comparing with cement concrete pavement, dense-graded HMA and S MA. Results of burning test and pavement performance test indicate that FRPA is appropriate and suitable as the pavement material of highway tunnel.

  1. 基于图像处理的沥青表面自由能测试%Test of surface free energy of asphalt with image processing

    Institute of Scientific and Technical Information of China (English)

    查旭东; 潘勤学; 陈武

    2011-01-01

    In order to evaluate the asphalt adhesion in a reasonable way,the test principle of surface free energy determined by the contact angle of interface between liquid and solid was analyzed in accordance with the theory of surface physical chemistry.The test method of surface free energy of asphalt based on the digital image processing was put forward,and the efficient algorithms were determined to detect the droplet edge clearly and accurately.Meanwhile,the method was put forward to fit the droplet edge with an elliptic curve.The experiments show that the elliptic curve is extremely fitted with the droplet edge pixels to represent the geometry of droplet edge well.Hereby,the contact angles can be calculated from the gradients of contact points on the elliptic curve.Then six kinds of asphalt and three kinds of known liquid were selected to make many practical tests of contact angles.The results show that the tested data are small in variability and high in accuracy.There are very good linear correlations between the contact angles and the surface free energy.The obtained surface free energy can accurately reflect the adhesion between asphalt and aggregate.Therefore,the test of surface free energy of asphalt with the technology of digital image processing is a rapid,accurate,reliable and convenient method to evaluate the asphalt adhesion,and the method can be applied in the engineering practice.%为了合理地评价沥青粘附性,基于表面物理化学理论,分析了由液固界面接触角确定表面自由能的测试原理,提出了基于数字图像处理的沥青表面自由能测试方法,并确定了图像处理的有效算法.由此提取的液滴边界清晰、定位准确.同时,提出了采用椭圆曲线对液滴边界进行拟合的方法.试验结果表明,椭圆曲线与液滴边界像素点非常吻合,很好地表征了液滴边界的几何形状;据此,由椭圆曲线在接触点处的斜率即可求出接触角.然后,选取了6种沥青和3种

  2. Simulation tests to assess occupational exposure to airborne asbestos from asphalt-based roofing products.

    Science.gov (United States)

    Mowat, Fionna; Weidling, Ryan; Sheehan, Patrick

    2007-07-01

    This study sought to evaluate exposure from specific products to evaluate potential risk from roof repair activities. Five asbestos-containing fibered roof coatings and plastic cements, representing a broad range of these types of products, were tested in exposure simulations. These products were applied to representative roof substrates. Release of asbestos fibers during application and sanding of the product shortly thereafter (wet sanding) were tested initially. Other roof substrates were cured to simulate a product that had been on a rooftop for several months and then were tested to evaluate release of fibers during hand sanding and hand scraping activities. Additional tests were also conducted to evaluate asbestos release during product removal from tools and clothing. Two personal (n = 84) and background/clearance (n = 49) samples were collected during each 30-min test and analyzed for total fiber concentration [phase-contrast microscopy (PCM)] and for asbestos fiber count [transmission electron microscopy (TEM)]. PCM concentrations ranged from <0.005 to 0.032 fibers per cubic centimeter (f cc(-1)). Chrysotile fibers were detected in 28 of 84 personal samples collected. TEM concentrations ranged from <0.0021 to 0.056 f cc(-1). Calculated 8-h time-weighted averages (TWAs) ranged from 0.0003 to 0.002 f cc(-1) and were comparable to the background TWA concentration of 0.0002 f cc(-1) measured in this study. Based on these results, it is unlikely that roofers were exposed to airborne asbestos concentrations above the current or historical occupational guidelines during scraping and sanding of these products during roof repair.

  3. Technology Solutions Case Study: Field Testing an Unvented Roof with Asphalt Shingles in a Cold Climate

    Energy Technology Data Exchange (ETDEWEB)

    K. Ueno and J. Lstiburek

    2015-09-01

    Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a "control" vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except the vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise.

  4. Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Kohta [Building Science Corporation, Westford, MA (United States); Lstiburek, Joseph W. [Building Science Corporation, Westford, MA (United States)

    2015-09-01

    Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).

  5. 抗滑级配沥青混合料体积参数及性能对比试验%Mentioned parameters and performance contrast test of anti-slide gradations of asphalt mixture

    Institute of Scientific and Technical Information of China (English)

    纪耀辉; 尤伟

    2011-01-01

    选用两种抗滑类型沥青混合料:AC-13K(又称改进型AK-13A),Superpave-13,按照马歇尔沥青混合料设计方法设计得出AC-13K型混合料的最佳级配和最佳沥青含量(为5.2%);按照Superpave法成型试件得到Superpave-13的最佳级配和最佳沥青含量(5.1%),对两种沥青混合料分别在已确定的级配形式和最佳沥青含量的情况下制备马歇尔试件,测定其主要参数,并进行了抗水损害试验和车辙试验,以了解两种沥青混合料的抗车辙性能和抗水损害性能。%This paper used two kinds of anti-slide type asphalt mixture: AC-13 K( also called improved type AK-13 A) , Superpave-13, according to Marshall asphalt mixture design method to design that the optimum level and the optimum asphalt content(5.2% ) of AC-13K mixture, according to the Superpave method molding to design the optimum gradation and the optimum asphalt content(5.1% ) of Superpave-13, to the two kinds of asphalt mixture respectively prepared Marshall specimen in the conditions of having been identified gradation form and the optimum asphalt content, determined its main parameters, and made the water damage resistance and rutting test, in order to understand the rutting resistance and water damage resistance of the two kinds of asphalt mixture.

  6. Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Kohta [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lstiburek, Joseph W. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except the vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).

  7. 沥青混合料结构类型的符合性检验方法%Conformance Testing Method of Asphalt Mixture Structure Types

    Institute of Scientific and Technical Information of China (English)

    葛折圣; 胡晓倩

    2012-01-01

    temperature deformation resistance was researched. The results show that the presented mixture structure type indicator Hmis/HDRC is closely related to the high temperature deformation resistance of mixture. The research result made up the shortcoming of existing specification, it is conducive to test the conformance of construction quality and design of asphalt pavement, control the pavement construction quality, and extend the service life of road.

  8. Mechanical properties of gutta-percha sulfide modified asphalt

    Science.gov (United States)

    Zou, X. Y.; Gu, X. Y.; Wang, X. W.

    2017-01-01

    Gutta-percha is the isomer of caoutchouc and can be used to enhance the performance of asphalt. In this paper, the produce proceedings of gutta-percha sulfide and gutta-percha sulfide modified asphalt are introduced. The performance indices of gutta-percha sulfide modified asphalt samples with different proportions are examined based on laboratory tests and the optimum ratio of gutta-percha and sulfur is decided.The micromechanism, temperature sensitivity, high and low temperature properties and viscoelasticity of the polymer modified asphalt are analyzed to discuss the modified mechanism and to decide the optimal polymer content. Low temperature bending tests are carried out to verify the low temperature performance of gutta-percha sulfide modified asphalt mixture. Research results showed that gutta-percha sulfide modified asphalt has good low temperature performance and a promising application prospect in the cold regions.

  9. Thermal Properties of Asphalt Mixtures Modified with Conductive Fillers

    Directory of Open Access Journals (Sweden)

    Byong Chol Bai

    2015-01-01

    Full Text Available This paper investigates the thermal properties of asphalt mixtures modified with conductive fillers used for snow melting and solar harvesting pavements. Two different mixing processes were adopted to mold asphalt mixtures, dry- and wet-mixing, and two conductive fillers were used in this study, graphite and carbon black. The thermal conductivity was compared to investigate the effects of asphalt mixture preparing methods, the quantity, and the distribution of conductive filler on thermal properties. The combination of conductive filler with carbon fiber in asphalt mixture was evaluated. Also, rheological properties of modified asphalt binders with conductive fillers were measured using dynamic shear rheometer and bending beam rheometer at grade-specific temperatures. Based on rheological testing, the conductive fillers improve rutting resistance and decrease thermal cracking resistance. Thermal testing indicated that graphite and carbon black improve the thermal properties of asphalt mixes and the combined conductive fillers are more effective than the single filler.

  10. Mutagenicity of bitumen and asphalt fumes.

    Science.gov (United States)

    Heikkilä, P R; Väänänen, V; Hämeilä, M; Linnainmaa, K

    2003-08-01

    The mutagenicity of asphalt fumes was tested with the Salmonella bioassays. The aim was to investigate if recycled additives modify the genotoxicity of emissions. Recycling of old asphalt is increasing, and we studied also the mutagenicity of emissions sampled during the re-use of asphalt. The composition of vapours and fumes were analysed by gas chromatography and by liquid chromatography. Bitumens containing coal fly ash (CFA) or waste plastics were heated to the paving temperatures in the laboratory. In the field, bitumen fumes were collected during paving of stone mastic asphalts (lime or CFA as a filler), remixing of stone mastic asphalt (lime or CFA as a filler), and of asphalt concrete. All the lab-generated vapour fractions were non-mutagenic. The particulate fractions were mutagenic with TA98 in the presence of the S9 activation. In addition, the lab-fumes from bitumen containing waste plastics were positive with both strains without S9. Only particulate fractions sampled in the field were tested. They were mutagenic with and without metabolic activation with both strains. The mutagenic potency of the field samples was higher than that of the lab-generated fumes without S9, and the remixing fumes were more mutagenic than the normal paving and lab-generated fumes with S9. The use of inorganic additive, CFA, did not change the mutagenicity of the fumes, whereas the organic additive, waste plastics, increased the mutagenicity of the laboratory emissions significantly.

  11. Performance of Recycled Porous Hot Mix Asphalt with Gilsonite Additive

    Directory of Open Access Journals (Sweden)

    Ludfi Djakfar

    2015-01-01

    Full Text Available The objective of the study is to evaluate the performance of porous asphalt using waste recycled concrete material and explore the effect of adding Gilsonite to the mixture. As many as 90 Marshall specimens were prepared with varied asphalt content, percentage of Gilsonite as an additive, and proportioned recycled and virgin coarse aggregate. The test includes permeability capability and Marshall characteristics. The results showed that recycled concrete materials seem to have a potential use as aggregate in the hot mix asphalt, particularly on porous hot mix asphalt. Adding Gilsonite at ranges 8–10% improves the Marshall characteristic of the mix, particularly its stability, without decreasing significantly the permeability capability of the mix. The use of recycled materials tends to increase the asphalt content of the mix at about 1 to 2% higher. With stability reaching 750 kg, the hot mix recycled porous asphalt may be suitable for use in the local roads with medium vehicle load.

  12. Asphalt in Pavement Maintenance.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    Maintenance methods that can be used equally well in all regions of the country have been developed for the use of asphalt in pavement maintenance. Specific information covering methods, equipment and terminology that applies to the use of asphalt in the maintenance of all types of pavement structures, including shoulders, is provided. In many…

  13. Hanford Permanent Isolation Barrier Program: Asphalt technology development

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Romine, R.A.

    1994-11-01

    An important component of the Hanford Permanent Isolation Barrier is the use of a two-layer composite asphalt system, which provides backup water diversion capabilities if the primary capillary barrier fails to meet infiltration goals. Because of asphalt`s potential to perform to specification over the 1000-year design life criterion, a composite asphalt barrier (HMAC/fluid-applied polymer-modified asphalt) is being considered as an alternative to the bentonite clay/high density poly(ethylene) barriers for the low-permeability component of the Hanford Permanent Isolation Barrier. The feasibility of using asphalt as a long-term barrier is currently being studied. Information that must be known is the ability of asphalt to retain desirable physical properties over a period of 1000 years. This paper presents the approach for performing accelerated aging tests and evaluating the performance of samples under accelerated conditions. The results of these tests will be compared with asphalt artifact analogs and the results of modeling the degradation of the selected asphalt composite to make life-cycle predictions.

  14. The Effect of Joint Width on Structural Performance of Asphalt Block Pavements

    Directory of Open Access Journals (Sweden)

    Ahmed Abdelgalil

    2014-02-01

    Full Text Available Asphalt blocks have been occasionally used around the world as a road pavement, but there have been very limited studies being done to evaluate the effect of joint width (spacing between the blocks on the structural performance of asphalt paving blocks. This study explains the experimental study to assess the performance and properties of asphalt paving blocks laid with different joint widths between the blocks i.e., 0, 2 and 3 mm, respectively. A total of 250 asphalt paving blocks was manufactured and tested in the laboratory to ascertain the density, air voids, the compressive strength and the rut depth and displacement occurred in asphalt paving block. The design compressive load of single asphalt paving block is 166 kN. The test results showed that the joint width plays a vital role on the performance of asphalt block pavement. Asphalt paving blocks were laid as closely in contact as possible (0 mm yields the best structural performance.

  15. Study on Producing Heavy Paving Asphalt

    Institute of Scientific and Technical Information of China (English)

    Liu Daosheng; Gao Zhirong; Huo Kaifu; Liao Kejian

    2002-01-01

    The highly viscous crude oil from Shuguang No. 1 zone of Liaohe oilfield features high density,high viscosity and low wax content. It contains no gasoline fraction and its diesel oil fraction yield is only 7.19%, which belongs to the low sulfur naphthenic stocks crude oil. Its heavy fraction is not suited for producing lubricating oil. Its heavy oil, which contains more resins and asphaltenes and less wax, is not an ideal feedstock for catalytic cracking, but is the ideal raw material for producing high-grade paving asphalt.Now this highly viscous crude oil is used as fuel oil after being emulsified in Liaohe oilfield, but its viscosity is so high that it cannot be atomized uniformly and burned completely, resulting not only in waste of oil resource but also in reduction of economical benefit. To make full use of this oil resource and alleviate the shortfall of high grade paving asphalt in China, various brands of asphalt meeting Q/SHR003-1998and ESSO specifications were developed by blending vacuum residue of the said oil and a blending component which are rich in aromatics and deficient in wax. The impact of blending component on properties of blended asphalt has been investigated and road performances of these blended asphalts were studied. The laboratory test results show that the blended asphalts have good road performance and antiaging property.

  16. Operational properties of nanomodified stone mastic asphalt

    Directory of Open Access Journals (Sweden)

    Inozemtsev Sergey Sergeevich

    2015-03-01

    Full Text Available In order to prolong the lifetime and to improve the quality of pavements made of asphalt concrete it is necessary to apply innovative solutions in the process of design of such building materials. In order to solve the problem of low durability of asphalt concrete a modifier was proposed, which consists of diatomite, iron hydroxide sol (III and silica sol. Application of the diatomite with nanoscale layer of nanomodifier allows getting a stone mastic asphalt, which has high values of physical and mechanical properties and allows refusing from expensive stabilizing additive. Mineral filler was replaced by diatomite, which has been modified by iron hydroxide sol (III and silica sol. Modified diatomite allows sorption of bitumen and increase the cohesive strength and resistance to shear at positive temperatures. The modified asphalt has higher resistance to rutting at high temperature, abrasion resistance at low temperature and impact of climatic factors: alternate freezing and thawing, wetting-drying, UV and IR radiations. It is achieved by formation of solid and dense bitumen film at the phase interface and controlling the content of light fractions of the bitumen. The modifier consists of sol of iron hydroxide, which blocks the oxidation and polymerization of bitumen during operation. The proposed material allows controlling the initial structure formation of stone mastic asphalt. It was shown that modern test methods allow assessing the durability of asphalt in the design phase compositions.

  17. Using Pyrolized Carbon Black (PCB) from Waste Tires in Asphalt Pavement (Part 1, Limestone Aggregate)

    OpenAIRE

    Park, Taesoon; Lovell, C. W.

    1996-01-01

    This study presents the viability of using PCB as an additive in hot mix asphalt concrete. Different ratios of PCB (5%, 10%, 15%, and 20% by weight of asphalt) were blended with two grades of asphalt (AC-10 and AC-20). The complete behaviors of the PCB modified asphalt concrete were investigated by comprehensive laboratory testing and evaluation. The Marshall method was used to determine the optimum binder content and the mechanical properties and void relationships were investigated by th...

  18. Research on the relationship between water stability and aggregate gradation of asphalt pavement

    OpenAIRE

    Zhao Bing; Zhao Bo

    2015-01-01

    In the early destruction of asphalt pavement, water damage is the most major form.In this paper, experimental study was conducted on the composition of asphalt concrete,Marshall specimens were made in different types of aggregate gradation with the same kind of asphalt. Water immersion tests were conducted in order to analysis the relationship between the water stability and aggregate gradation of asphalt pavement.

  19. Adhesion Evaluation of Asphalt-Aggregate Interface Using Surface Free Energy Method

    OpenAIRE

    Jie Ji; Hui Yao; Luhou Liu; Zhi Suo; Peng Zhai; Xu Yang; Zhanping You

    2017-01-01

    The influence of organic additives (Sasobit and RH) and water on the adhesion of the asphalt-aggregate interface was studied according to the surface free energy theory. Two asphalt binders (SK-70 and SK-90), and two aggregate types (limestone and basalt) were used in this study. The sessile drop method was employed to test surface free energy components of asphalt, organic additives and aggregates. The adhesion models of the asphalt-aggregate interface in dry and wet conditions were establis...

  20. Research on the relationship between water stability and aggregate gradation of asphalt pavement

    Directory of Open Access Journals (Sweden)

    Zhao Bing

    2015-05-01

    Full Text Available In the early destruction of asphalt pavement, water damage is the most major form.In this paper, experimental study was conducted on the composition of asphalt concrete,Marshall specimens were made in different types of aggregate gradation with the same kind of asphalt. Water immersion tests were conducted in order to analysis the relationship between the water stability and aggregate gradation of asphalt pavement.

  1. Creep Characteristics of Crumb Rubber Modified Asphalt Binder

    Institute of Scientific and Technical Information of China (English)

    WANG Lan; CHANG Chunqing; XING Yongming

    2011-01-01

    Crumb rubber modified asphalt containing 20 percent crumb rubber particles of 30mesh has been examined by Scanning Electron Microscope (SEM) to observe the microcosmic appearance and the characteristic distribution of crumb rubber particles in asphalt. The SEM pictures reveal that the crumb rubber particles distribute evenly in the asphalt and they are compatible well with asphalt. The shear creep test of crumb rubber modified asphalt was carried out at - 10 ℃ and 40 ℃ by Dynamic Shear Rheology (DSR). The shearing deformation at different temperature and creep stiffness modulus curve at loading stage of crumb rubber modified asphalt have been measured. The stiffness modulus of crumb rubber modified asphalt is much temperature sensitive and it decays much quick at the early stage of loading than normal asphalt. The rate of decay of stiffness modulus is slow at the subsequent stage and stiffness modulus approaches to a stable value at the final stage at a higher temperature. In addition, Burgers model is suitable to describe and simulate experimental results of viscoelastic properties of the crumb rubber modified asphalt.

  2. Ethanol based foamed asphalt as potential alternative for low emission asphalt technology

    Directory of Open Access Journals (Sweden)

    Mohd Rosli Mohd Hasan

    2016-04-01

    Full Text Available Foamed asphalt typically relies on water as a foaming agent because water becomes gaseous at elevated temperatures, generating numerous tiny bubbles in the asphalt and causing spontaneous foaming. In this study, ethanol was used as a potential alternative to water as a foaming agent. Ethanol is expected to be a physical blowing agent in the same manner as water, except it requires less energy to foam due to its 78 °C boiling point. This study compares the performance of water and ethanol as foaming agents through the measurements of rotational viscosity, the reduction in temperature during foaming, and volatile loss. The ethanol-foamed asphalt binders were prepared at 80 °C and 100 °C, while the water-foamed asphalt binders were prepared at 100 °C and 120 °C. Additionally, the rolling thin film oven (RTFO was used to generate short-term aging of the foamed asphalt binders. A rotational viscometer was used to determine the viscosity of the asphalt binders at 80 °C, 100 °C, 120 °C, 140 °C, and 160 °C. Overall, ethanol can function in the same manner as water but requires less energy to foam. It is proven based on the smaller drop in temperature of the asphalt binder foamed using ethanol compared with that prepared with water. This is due to the lower latent heat capacity of ethanol, which requires less energy to vaporize compared with water. Through the rotational viscometer test, ethanol performs better in lowering the viscosity of asphalt binders, which is essential in allowing production processes at low temperatures, as well as a better workability and aggregate coating. Ethanol can be expelled from the foamed asphalt binders at a higher rate due to its lower boiling point and latent heat.

  3. Preparation of Flame Retardant Modified with Titanate for Asphalt Binder

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-01-01

    Full Text Available Improving the compatibility between flame retardant and asphalt is a difficult task due to the complex nature of the materials. This study explores a low dosage compound flame retardant and seeks to improve the compatibility between flame retardants and asphalt. An orthogonal experiment was designed taking magnesium hydroxide, ammonium polyphosphate, and melamine as factors. The oil absorption and activation index were tested to determine the effect of titanate on the flame retardant additive. The pavement performance test was conducted to evaluate the effect of the flame retardant additive. Oxygen index test was conducted to confirm the effect of flame retardant on flame ability of asphalt binder. The results of this study showed that the new composite flame retardant is more effective in improving the compatibility between flame retardant and asphalt and reducing the limiting oxygen index of asphalt binder tested in this study.

  4. Effect of ageing on fatigue properties of asphalt

    Institute of Scientific and Technical Information of China (English)

    王佶; 庞凌; 吴少鹏; 刘全涛; 陈筝

    2008-01-01

    The fatigue properties of asphalts were investigated after various laboratory simulation ageing tests and outdoor natural exposure ultraviolet radiation ageing,by dynamic shear rheometer(DSR) time sweep fatigue test in constant strain model and a new type of specimen which was introduced to avoid the problem of adhesion failure between rotor and asphalt binder.The results show that outdoor natural exposure ageing(NEA) causes the decrease of retained fatigue life distinctly,and photodegradation caused by outdoor NEA of 1 250 μm thin films asphalt for three months,is found to be severer than pressure ageing vessel(PAV) with respects to retained fatigue life.The effect of photodegradation increases as the time of outdoor NEA increases.DSR time sweep fatigue test in constant strain indicates that the aged styrene-butadiene-styrene(SBS) modified asphalt still displays better fatigue properties than the corresponding base asphalt after ageing.

  5. Laboratory performance of asphalt rubber mixtures

    OpenAIRE

    Fontes, Liseane; Trichês, Glicério; Pais, Jorge; Pereira, Paulo; Minhoto, Manuel

    2009-01-01

    Asphalt rubber mixtures are one of the most promising techniques to extend the service life of asphalt pavement overlays. Asphalt rubber binder is composed of crumb rubber from reclaimed tires and conventional asphalt. The asphalt rubber binder can be obtained through wet process in two different systems: tire rubber modified asphalt binder (produced at industrial plants) and continuous blending (produced in asphalt plants). This study presents a laboratory evaluation of asphalt rubber mixtur...

  6. Essais préliminaires de combustion d'asphaltes par la technique du charbon pulvérisé Preliminary Tests of Asphalt Combustion by the Pulverized Coal Technique

    Directory of Open Access Journals (Sweden)

    Flament G.

    2006-11-01

    Full Text Available Les possibilités offertes par le procédé de désasphaltage étudié à L'Institut Français du Pétrole (IFP sont rapidement exposées. On montre en particulier que les asphaltes recueillis grâce à ce procédé ont des propriétés physiques telles, qu'il est possible de s'en servir comme combustible et donc de les valoriser sur le plan énergétique. The possibilities offered by the deasphalting process researched by Institut Français du Pétrole (IFP are briefly described. It is shown in particular that the types of asphalts gathered by means of this process have physical properties enabling them to be used as a fuel so that they can be upgraded from the energy standpoint.

  7. Stabilization/solidification of munition destruction waste by asphalt emulsion.

    Science.gov (United States)

    Cervinkova, Marketa; Vondruska, Milan; Bednarik, Vratislav; Pazdera, Antonin

    2007-04-02

    Destruction of discarded military munitions in an explosion chamber produces two fractions of hazardous solid waste. The first one is scrap waste that remains in the chamber after explosion; the second one is fine dust waste, which is trapped on filters of gas products that are exhausted from the chamber after explosion. The technique of stabilization/solidification of the scrap waste by asphalt emulsion is described in this paper. The technique consists of simple mixing of the waste with anionic asphalt emulsion, or two-step mixing of the waste with cationic asphalt emulsion. These techniques are easy to use and the stabilized scrap waste proves low leachability of contained heavy metals assessed by TCLP test. Hence, it is possible to landfill the scrap waste stabilized by asphalt emulsion. If the dust waste, which has large specific surface, is stabilized by asphalt emulsion, it is not fully encapsulated; the results of the leaching tests do not meet the regulatory levels. However, the dust waste solidified by asphalt emulsion can be deposited into an asphalted disposal site of the landfill. The asphalt walls of the disposal site represent an efficient secondary barrier against pollutant release.

  8. Research on fracture performance of epoxy asphalt concrete based on double-K fracture criterion

    Science.gov (United States)

    Zhang, M.; Qian, Z. D.; Xue, Y. C.

    2017-01-01

    After cracks appear on steel bridge deck epoxy asphalt concrete pavement, cracks propagate fast under vehicle load. This paper studied the fracture performance of epoxy asphalt concrete, utilized single edge notched beam (SEB) three-point bending test, measured the load (P) exerted on epoxy asphalt SEB; utilized digital camera to record the fracture process of epoxy asphalt SEB, extracted the images according to the required sampling frequency and utilized Image-Pro Plus to measure the crack mouth opening displacement (CMOD) of epoxy asphalt SEB on the extracted images; calculated the double-K fracture parameters according to the P-CMOD curve. Results indicate that of epoxy asphalt concrete is 1.11 MPa and of epoxy asphalt concrete is 2.31 MPa at -15°C of epoxy asphalt concrete is 1.02 MPa and of epoxy asphalt concrete is 1.83 MPa at -5°C of epoxy asphalt concrete is 0.77 MPa and of epoxy asphalt concrete is 1.82 MPa at 5°C. The double-K fracture parameters of epoxy asphalt concrete increase slightly when the temperature decreases at the scope of -15°C to 5°C. The relation of and is .

  9. Preparation and Performance of Asphalt Compound Modified with Waste Crumb Rubber and Waste Polyethylene

    Directory of Open Access Journals (Sweden)

    Yuqiao Yang

    2016-01-01

    Full Text Available Three kinds of modified asphalt were prepared by adding waste crumb rubber (WCR, waste polyethylene (WPE, and WCR/WPE to base asphalt, respectively. The influence of different doses on the performance of modified asphalt, such as 25°C penetration, softening point, 5°C ductility, and 135°C, 165°C viscosity, was studied, and the modification mechanism of modified asphalt was discussed through the fluorescence microscope. As the waterproofing materials, the waterproofness of WCR/WPE compound modified asphalt was tested. The results show that the WPE modified asphalt has excellent resistance to high temperature and WCR modified asphalt has good low temperature resistance. The resistance to deformation ability of WPE modified asphalt is better than that of the WCR modified asphalt. The 135°C viscosity of compound modified asphalt is better than that of WPE and WCR modified asphalt. In addition, the waterproofness of compound modified asphalt using waterproofing materials is better than that of common waterproofing materials.

  10. Mechanism of Fume Suppression and Performance on Asphalt of Expanded Graphite for Pavement under High Temperature Condition

    Institute of Scientific and Technical Information of China (English)

    HUANG Gang; HE Zhaoyi; HUANG Yangcheng; ZHOU Chao; YUAN Xiaoya

    2014-01-01

    Fume suppression mechanisms and the effect of expanded graphite on the performance of asphalt were studied by applying infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and comprehensive thermal analysis (TG, DSC). The experimental results confirm that asphalt which is mixed with expandable graphite will expand in the process of hot mix, and the expanded graphite layer will swell by the light component in the asphalt. The light component in the asphalt and PAHs adsorption on expanded graphite surface or part of the plug in the expanded graphite layer between plates made nucleation crystallization growth. And the Van der Waals force and the bonding of the lattice can effectively restrain the asphalt fume release. Meanwhile, the expanding agent with oxidative can spread into the asphalt, leading to asphalt oxygenated and plastic abate, while the ductility decreases. Expanded graphite, SBS modifier and environment- friendly plasticizers are used to composite modified asphalt. According to asphalt fume release experiment, normal test of asphalt performance, Brookfield viscosity test, RTFOT test and asphalt mixture tests (high temperature stability, low temperature stability, water stability), it has been proven that the modified asphalt’s performance is better than that of matrix asphalt and equivalent to that of SBS modified asphalt. Furthermore, it has good fume suppression effect.

  11. Evaluation of Warm Mix Asphalt Additives for Use in Modified Asphalt Mixtures

    Science.gov (United States)

    Chamoun, Zahi

    The objective of this research effort is to evaluate the use of warm-mix additives with polymer modified and terminal blend tire rubber asphalt mixtures from Nevada and California. The research completed over two stages: first stage evaluated two different WMA technologies; Sasobit and Advera, and second stage evaluated one additional WMA technology; Evotherm. The experimental program covered the evaluation of resistance of the mixtures to moisture damage, the performance characteristics of the mixtures, and mechanistic analysis of mixtures in simulated pavements. In the both stages, the mixture resistance to moisture damage was evaluated using the indirect tensile test and the dynamic modulus at multiple freeze-thaw cycles, and the resistance of the various asphalt mixtures to permanent deformation using the Asphalt Mixture Performance Tester (AMPT). Resistance of the untreated mixes to fatigue cracking using the flexural beam fatigue was only completed for the first stage. One source of aggregates was sampled in, two different batches, three warm mix asphalt technologies (Advera, Sasobit and Evotherm) and three asphalt binder types (neat, polymer-modified, and terminal blend tire rubber modified asphalt binders) typically used in Nevada and California were evaluated in this study. This thesis presents the resistance of the first stage mixtures to permanent deformation and fatigue cracking using two warm-mix additives; Advera and Sasobit, and the resistance to moisture damage and permanent deformation of the second stage mixtures with only one warm-mix additive; Evotherm.

  12. Durability ofAsphalt in Different Corrosion Solution

    Institute of Scientific and Technical Information of China (English)

    CHEN Shuanfa; GUAN Bowen; XIONG Rui; SHENG Yanping; HE Rui

    2011-01-01

    The corrosion to asphalt mixture under different kinds of corrosion solution,such as pH=2 solution,pH=12 solution,pH =12 solution and 10% Na2SO4 solution,was studied.The performance attenuation of asphalt mixture was analyzed under the normal environment and the freeze-thaw environment,and the analysis was given on the sensitivity of the test results to the evaluation index.The experimental results show that the performance of asphalt mixture is attenuated faster under the acidic solution,alkaline solution and sulfate solution.Corrosion factor Kc,freeze-thaw corrosion factor Kf,and freeze-thaw effect factor Kfc are proposed to evaluate asphalt mixture resistance to corrosion in different kinds of corrosion solution.The values of Kc and Kfc decrease with the increasing of corrosion time.The change rule of Kf show that the rate of corrosion is decreased by the action of freeze-thaw in acidic solution and in alkaline solution,but is increased by the action of freeze-thaw in sulfate solution.The microscopic analysis indicates that acid solution reacts with aggregate of asphalt mixture,alkaline solution reacts with asphalt cement of asphalt mixture,the surface tension of sulfate solution and crystallization of sulfate are the main reasons which weak the performance of asphalt mixture.

  13. The effect of aggregate density on pavement performance of SMA-13 asphalt mixture

    Directory of Open Access Journals (Sweden)

    Qiao Yinping

    2016-05-01

    Full Text Available This paper chooses the top layer SMA-13 asphalt mixture material as the research object. Basalt was selected as pavement material, and modified SBS asphalt was used as a cementing material. Two basalt aggregates with different densities were used to carry out standard Marshall test in the laboratory.Aimed at the volume parameters of the asphalt mixture carry on anaiysis,and obtian the effect of aggregate density on pavement performance of SMA-13 asphalt mixture, which is that the density of aggregate has a significant effect on the void ratio, saturation, and the gap rate of the aggregate, thus affecting the pavement performance of the asphalt mixture

  14. Influence of conductive additive on temperature susceptibility of asphalt binders

    Institute of Scientific and Technical Information of China (English)

    吴少鹏; 李波; 陈筝; 黄旭

    2008-01-01

    The effects of graphite on temperature susceptibility of asphalt binders were investigated by penetration test,Ring & Ball softening point test and viscosity test.And penetration index(IP),viscosity-temperature susceptibility(SVT),and penetration-viscosity numbers(NPV) were introduced to evaluate the effects.The results show that the penetration,softening point and viscosity of asphalt binder increase with the increase of content of graphite.This means that the addition of graphite makes asphalts stiffer.The results from IP,NPV and SVT show that temperature susceptibility is reduced by the addition of graphite.

  15. Thiol/disulfide homeostasis in asphalt workers.

    Science.gov (United States)

    Yilmaz, Ömer Hınç; Bal, Ceylan; Neşelioglu, Salim; Büyükşekerci, Murat; Gündüzöz, Meşide; Eren, Funda; Tutkun, Lutfiye; Yilmaz, Fatma Meric

    2016-09-02

    The aim of this study was to investigate thiol/disulfide homeostasis in asphalt workers who are exposed to polycyclic aromatic hydrocarbons occupationally. The study was carried out in 34 nonsmoker asphalt workers. Additionally, 35 healthy nonsmoker volunteers were recruited as control group. Thiol and disulfide concentrations were determined using the novel automated measurement method. Levels of urinary 1-OH-pyrene were analyzed by liquid chromatography. Disulfide/thiol ratio was significantly higher in exposed group (p = .034). Also, a positive correlation was detected between disulfide/thiol ratio and 1-OH-pyrene values (r = .249, p = .036). Thiol/disulfide homeostasis was found to be disturbed in asphalt workers. The novel test used in this study may be useful for evaluating the oxidative status in polycyclic aromatic hydrocarbon (PAH) exposure.

  16. Laboratory and Field Evaluation of In-Place Asphalt Recycling Technologies for Small Airfield Repair

    Science.gov (United States)

    2013-06-01

    Recommendation of materials, equipment and process for in-place asphalt recycling Part I Laboratory Evaluation RAP Material Characterization • Binder...laboratory testing based upon their chemical properties and costs. Reclaimed asphalt pavement ( RAP ) material was obtained from both test sites for...Part I of this study was to conduct laboratory testing to:  characterize the reclaimed asphalt pavement ( RAP ) from the test sites,  evaluate how

  17. Adhesion Evaluation of Asphalt-Aggregate Interface Using Surface Free Energy Method

    Directory of Open Access Journals (Sweden)

    Jie Ji

    2017-02-01

    Full Text Available The influence of organic additives (Sasobit and RH and water on the adhesion of the asphalt-aggregate interface was studied according to the surface free energy theory. Two asphalt binders (SK-70 and SK-90, and two aggregate types (limestone and basalt were used in this study. The sessile drop method was employed to test surface free energy components of asphalt, organic additives and aggregates. The adhesion models of the asphalt-aggregate interface in dry and wet conditions were established, and the adhesion work was calculated subsequently. The energy ratios were built to evaluate the effect of organic additives and water on the adhesiveness of the asphalt-aggregate interface. The results indicate that the addition of organic additives can enhance the adhesion of the asphalt-aggregate interface in dry conditions, because organic additives reduced the surface free energy of asphalt. However, the organic additives have hydrophobic characteristics and are sensitive to water. As a result, the adhesiveness of the asphalt-aggregate interface of the asphalt containing organic additives in wet conditions sharply decreased due to water damage to asphalt and organic additives. Furthermore, the compatibility of asphalt, aggregate with organic additive was noted and discussed.

  18. 含层间界面的沥青混合料复合小梁弯曲疲劳试验%Flexural Fatigue Test on Beams of Asphalt Mixture Involving Inter-surface

    Institute of Scientific and Technical Information of China (English)

    艾长发; 成猛; 杨涛; 邱延峻

    2011-01-01

    为探讨层间界面条件对沥青路面疲劳寿命的影响,完善路面疲劳模型,采用小梁弯曲疲劳试验方法,测定不同粘层油用量、不同温度、不同加载等试验条件下复合小梁试件的疲劳寿命.研究结果表明:(1)由于层间界面的存在,导致沥青路面结构整体性减弱,疲劳寿命减小;(2)随着粘层油用量的增加,疲劳寿命呈现先增加后减小的变化规律,并且粘层油用量存在一个最佳值,在此最佳用量下,沥青路面的抗疲劳性能明显提高;(3)与低温条件相比,常温条件下沥青路面的疲劳破损更容易发生,并且车辆超载,轴重增大,会显著降低沥青路面的疲劳寿命;(4)确定了疲劳寿命与粘层油用量、温度、加载量之间的相互关系,通过数值回归分析,建立了疲劳寿命与各影响因素之间的相互作用关系式.%The fatigue life of composite beam samples were measured using method of flexural fatigue test in different tack asphalt coat contents, temperatures and loads to study the influence of interlamination contact on the fatigue life of asphalt pavement and perfect the pavement fatigue model. The results show that (1) the integrity and fatigue life of asphalt pavement decreased due to the existence of interlamination contact; (2) the fatigue life first increased, then decreased with the increase of the content of tack asphalt coat, and there was an optimum content of tack asphalt coat for usage, which can put the fatigue resistance in a higher level; (3) the fatigue failure would happen more easily at normal temperature than at low temperature, and the fatigue life would decrease significantly if vehicle is overweight; (4) the relation of fatigue life with content of tack asphalt coat, temperature and load was found out, and the total fatigue equations were set up.

  19. The Test of Adhesion between TLA Modified Asphalt with Limestone and Calcite%TLA改性沥青与石灰石、方解石的粘附性试验

    Institute of Scientific and Technical Information of China (English)

    何萍

    2012-01-01

    The paper investigated the test of adhesion between TLA modified asphalt with limestone and calcite. The results show that adhesion between TLA modified asphalt with limestone and calcite are fifth grade. Because calcite is a soft stone, the pure calcite is cleared out by hand and the content of calcite in limestone is strictly controlled in the highway construction.%TLA改性沥青与石灰岩、方解石的粘附性试验表明:TLA改性沥青与石灰岩、方解石的粘附性均为5级.方解石属于软石,对于石灰岩中纯净的方解石应通过人工挑选的方法加以清除,对于夹杂有方解石的石灰岩应严格控制石灰岩中方解石的含量.

  20. Analysis of Adhesive Characteristics of Asphalt Based on Atomic Force Microscopy and Molecular Dynamics Simulation.

    Science.gov (United States)

    Xu, Meng; Yi, Junyan; Feng, Decheng; Huang, Yudong; Wang, Dongsheng

    2016-05-18

    Asphalt binder is a very important building material in infrastructure construction; it is commonly mixed with mineral aggregate and used to produce asphalt concrete. Owing to the large differences in physical and chemical properties between asphalt and aggregate, adhesive bonds play an important role in determining the performance of asphalt concrete. Although many types of adhesive bonding mechanisms have been proposed to explain the interaction forces between asphalt binder and mineral aggregate, few have been confirmed and characterized. In comparison with chemical interactions, physical adsorption has been considered to play a more important role in adhesive bonding between asphalt and mineral aggregate. In this study, the silicon tip of an atomic force microscope was used to represent silicate minerals in aggregate, and a nanoscale analysis of the characteristics of adhesive bonding between asphalt binder and the silicon tip was conducted via an atomic force microscopy (AFM) test and molecular dynamics (MD) simulations. The results of the measurements and simulations could help in better understanding of the bonding and debonding procedures in asphalt-aggregate mixtures during hot mixing and under traffic loading. MD simulations on a single molecule of a component of asphalt and monocrystalline silicon demonstrate that molecules with a higher atomic density and planar structure, such as three types of asphaltene molecules, can provide greater adhesive strength. However, regarding the real components of asphalt binder, both the MD simulations and AFM test indicate that the colloidal structural behavior of asphalt also has a large influence on the adhesion behavior between asphalt and silicon. A schematic model of the interaction between asphalt and silicon is presented, which can explain the effect of aging on the adhesion behavior of asphalt.

  1. Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Shakir.A.Al-Mishhadani

    2014-02-01

    Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.

  2. Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Shakir.A.Al-Mishhadani* Hasan.H.Al-Baid

    2014-04-01

    Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.  

  3. Modified rubberized stone matrix asphalt for Nineveh roads

    Institute of Scientific and Technical Information of China (English)

    Al-Hadidy AI; TAN Yi-qiu

    2008-01-01

    To evaluate the effects of Crumb Rubber Modifiers (CRMS) on basic engineering properties (i. e.Marshall, tensile strength, and compressive strength) of stone matrix asphalt mixtures, the ASTM testing and procedures were employed. Results of the evaluation were used to quantify the effect of CRM source and CRM content on engineering properties at testing temperatures of 25℃and 60℃. Statistical models were developed, which represent the nature of effects on performance-related properties of stone matrix asphalt mixtures.

  4. 磷渣微粉基隧道沥青路面阻燃剂的制备及其性能试验%Preparation and performance test phosphorus slag powder base tunnel asphalt pavement retardants

    Institute of Scientific and Technical Information of China (English)

    钱国平; 王坤; 郑卫芳

    2016-01-01

    针对隧道沥青路面防火安全问题,配制了6种磷渣微粉基材阻燃剂 A~F。通过 DSC 试验评价了各阻燃剂阻燃性能,选出了最优阻燃剂;对掺入不同掺量的阻燃改性沥青进行路用性能试验和极限氧指数试验,分析了阻燃剂最佳掺量和阻燃效果;采用锥形热试验对阻燃沥青混合料进行阻燃性能研究。试验结果表明,阻燃剂 D,F 有明显的两个吸热峰;阻燃剂 D 和 F 的加入使沥青的氧指数得到显著的提高;不同掺量阻燃剂 D,F 的加入,能够满足沥青路用性能的要求,阻燃剂的最佳掺量为8%;与非阻燃改性沥青混合料相比,阻燃改性沥青的引燃时间变长,热释放速率减缓,总释热量全过程低于非阻燃沥青混合料。阻燃剂 D,F 的加入对沥青及沥青混合料的阻燃效果明显,且阻燃剂 D 阻燃效果最优。%Six kinds of phosphorus slag powder-based flame retardants were prepared in or-der to solve fire-proof safety problem of tunnel asphalt pavement A-F.The combustion prop-erties of flame retardants were evaluated by DSC experiment and the optimal flame retard-ants were selected.The pavement performance and limiting oxygen index of flame-retardant modified asphalt with different amounts of retardants were tested,then the optimum a-mount of flame retardants and flame retardancy were analyzed.The Cone thermal test was conducted to study the flame retardant properties of flame retardant asphalt mixture.the re-sults show that flame D,F two endothermic peaks are obvious.With the addition of flame retardant D and F,the oxygen index of asphalt was significantly improved.Different dosage of the addition of flame retardant D,F can meet the requirements of the pavement perform-ance.The optimum amount of flame retardant is 8%.Compared with the nonflame-retardant asphalt mixture,the retardancy of flame-retardant modified asphalt mixture is better:its ig-nition time is longer,heat release rate is slower and the

  5. Discrete Element Simulation of Asphalt Mastics Based on Burgers Model

    Institute of Scientific and Technical Information of China (English)

    LIU Yu; FENG Shi-rong; HU Xia-guang

    2007-01-01

    In order to investigate the viscoelastic performance of asphalt mastics, a micro-mechanical model for asphalt mastics was built by applying Burgers model to discrete element simulation and constructing Burgers contact model. Then the numerical simulation of creep tests was conducted, and results from the simulation were compared with the analytical solution for Burgers model. The comparision snowed that the two results agreed well with each other, suggesting that discrete element model based on Burgers model could be employed in the numerical simulation for asphalt mastics.

  6. Effect of fiber types on relevant properties of porous asphalt

    Institute of Scientific and Technical Information of China (English)

    WU Shao-peng; LIU Gang; MO Lian-tong; CHEN Zheng; YE Qun-shan

    2006-01-01

    The research was conducted to evaluate the effects of cellulose and polyester fibers on the properties of porous asphalt mixes,using the tests of draindown,abrasion,volumetric properties,rutting,and moisture damage. Images of scanning electron microscopy and X-ray computerized tomography were adopted to identify the microstructure of the fiber and inner stone skeleton of porous asphalt. The influence of rutting parameter (G*/sinδ) of asphalt modified by different fibers on the rutting resistance of the mixes was investigated. Based upon Mohr-Coulomb theory,the cohesion and the angle of internal friction of the mixes were derived from both indirect tension and unconfined compression strength. The experimental results indicate that fibers mainly stabilize asphalt binder and thicken asphalt film around aggregates. Furthermore,they result in the improved mechanical strength of porous asphalt mixes at high temperature slightly. From comparison analysis,cellulose fibers appear to perform better than polyester fibers in porous asphalt mixes.

  7. Reinforcement of Recycled Foamed Asphalt Using Short Polypropylene Fibers

    Directory of Open Access Journals (Sweden)

    Yongjoo Kim

    2013-01-01

    Full Text Available This paper presents the reinforcing effects of the inclusion of short polypropylene fibers on recycled foamed asphalt (RFA mixture. Short polypropylene fibers of 10 mm length with a 0.15% by weight mixing ratio of the fiber to the asphalt binder were used. The Marshall stability test, the indirect tensile strength test, the resilient modulus test, and wheel tracking test of the RFA mixtures were conducted. The test results were compared to find out the reinforcing effects of the inclusion of the fiber and the other mixtures, which included the conventional recycled foamed asphalt (RFA mixtures; the cement reinforced recycled foamed asphalt (CRFA mixtures; the semihot recycled foamed asphalt (SRFA mixtures; and recycled hot-mix asphalt (RHMA mixtures. It is found that the FRFA mixture shows higher Marshall stability than the RFA and SRFA mixtures, higher indirect tensile strength than the RFA mixture, and higher rut resistance than the RFA, SRFA, and RHMA mixtures as seen from the wheel tracking test.

  8. Asphalt for draining pavement; Haisuisei hosoyo asphalt

    Energy Technology Data Exchange (ETDEWEB)

    Yamamori, H.; Nakamura, Y. [Mitsubishi Oil Co. Ltd., Tokyo (Japan)

    1994-12-28

    The effect and functions of draining pavement with a superb performance as a paved road were introduced. In the draining pavement, a porous asphalt mixture was used for the surface and base layers of the road and the remaining layers are not in water penetration property. It is necessary that void continues to prevent water film from being generated when rain falls and resistance against water flow is small but durability has problems when the void rate is large. According to the balance, the void rate ranges from 20 to 23 % for execution, thus preventing water splash on a rainy day, hydroplaning, and dazzlement, etc. due to reflection of light. The noise during driving due to the tire of an automobile is reduced by 5 to 6 dB owing to draining pavement. Also, engine noise is reduced to 40 - 60 % since the surface is porous. In the draining pavement, a high-viscosity asphalt is used for a binder and the void rate is large, thus preventing temperature to rise easily due to heat release and achieving an improved flow behavior. 6 refs., 11 figs., 14 tabs.

  9. Essais préliminaires de combustion d'asphaltes par la technique du charbon pulvérisé Preliminary Tests of Asphalt Combustion by the Pulverized Coal Technique

    OpenAIRE

    Flament G.; Mauss F.

    2006-01-01

    Les possibilités offertes par le procédé de désasphaltage étudié à L'Institut Français du Pétrole (IFP) sont rapidement exposées. On montre en particulier que les asphaltes recueillis grâce à ce procédé ont des propriétés physiques telles, qu'il est possible de s'en servir comme combustible et donc de les valoriser sur le plan énergétique. The possibilities offered by the deasphalting process researched by Institut Français du Pétrole (IFP) are briefly described. It is shown in particular ...

  10. Analysis of asphalt mixtures on town roads

    OpenAIRE

    Glavica, Primož

    2006-01-01

    Asphalt mixtures are most commonly used composite for construction of top layers of different drive ways. By definition asphalt mixtures are composed of crushed rock, fill, bitumen and additives. Percentage of individual components wary according to the purpose asphalt mixture is to be used for. Asphalt mixtures must be capable of enduring different types of load. According to the type of load asphalt mixtures are divided into asphalt mixtures used for supporting layers and asp...

  11. A review of asphalt and asphalt mixture aging

    Directory of Open Access Journals (Sweden)

    Wilmar Darío Fernández-Gómez

    2012-09-01

    Full Text Available This paper presents an extensive review of the pertinent literature regarding asphalt and asphalt mixture Aging. Aging affects flexible pavement performance and is produced by intrinsic and extrinsic variables as well as exposure time. Intrinsic variables include asphalt and aggregate properties, a mixture’s asphalt content, binder film thickness and air void content; extrinsic variables are associated with production (short-term aging and exposure to environmental field conditions (long-term aging. Taken together, both variables demonstrate that aging results from three distinct mechanisms: volatilisation, oxidation and steric hardening. Temperature, pressure and photo degradation treatments are used to simulate aging in the laboratory and empirical and semi-empirical models are created to represent and study aging. Aging increases asphalt complex modulus and decreases the phase angle. Mixtures become stiffer while fatigue life becomes reduced. Carbonyl and sulfoxide group formation in asphalt are often studied as such chemical changes show oxidation in aged asphalts. The prevailing models used to predict asphalt aging are discussed, though more comprehensive research into asphalt aging is still needed.

  12. Research on Asphalt Mixture Permanent Deformation by Single Penetration Repeated Shear Test%基于单轴贯入重复剪切试验的沥青混合料永久变形

    Institute of Scientific and Technical Information of China (English)

    许严; 孙立军; 刘黎萍

    2013-01-01

    沥青路面车辙变形越发严重,降低路面使用寿命的同时大大影响行车安全.通过对比分析,提出运用单轴贯入重复剪切试验研究沥青混合料的永久变形.对高速公路沥青路面上中面层最常用的4种沥青混合料进行了不同荷载水平下的单轴贯入重复剪切试验,得到如下结论:单轴贯入重复剪切试验可以做出沥青混合料的三阶段变形;荷载越大混合料永久变形的速率越大,剪切疲劳寿命或流动数越小,当荷载大于或等于1.3 MPa时改性沥青混合料在较小的荷载次数内变形过大,发生剪切破坏,而当荷载小于或等于1.1MPa时变形增加极慢,稳定地处于变形的第二阶段而不破坏;抗剪强度较大的沥青混合料抵抗剪切变形的能力较强,改性沥青混合料抵抗剪切变形的能力远大于普通沥青混合料;荷载应力水平和作用次数具有等效性.%The pavement rutting is getting worse,which shortens the pavement service life,and the driving safety is therefore affected.A single penetration repeated shear test (SPRST) was proposed for a research on asphalt mixture permanent deformation on the basis of a comparative analysis.Many SPRST tests on different load levels were made with four kinds of the most commonly used asphalt mixtures in the upper and middle layer of asphalt pavements.Test results show that the three-stage permanent deformation behavior of asphalt mixtures on loads can be obtained by SPRST.The bigger the load is,the faster the permanent deformation of asphalt mixtures increases and the smaller the shear fatigue life or the flow number is.A larger load (≥1.3 MPa) brings about large deformation without large load cycles and the mixture breaks; but the smaller load (≤1.1MPa) gives rise to a slow increase of deformation,which is stable in the second stage.The asphalt mixtures with bigger shear strength have a greater ability to resist the shear deformation than conventional asphalt

  13. Resistivity-temperature Characteristics of Conductive Asphalt Concrete

    Institute of Scientific and Technical Information of China (English)

    SUN Wenzhou; LI Xu; YANG Qun; ZHANG Hongwei

    2016-01-01

    The changes of resistivity of conductive asphalt concrete at different temperatures were studied, and positive temperature coefficient (PTC) model was established to estimate the influence of temperature on the resistivity quantitatively, which eliminated the interference with conductivity evaluation brought by temperature variation. Finally, the analysis of temperature cycling test results proves that the changes of percolation network structure caused by temperature variation prompt the emergence of PTC of conductive asphalt concrete.

  14. Rheological properties of asphalt mixtures containing various fibers

    Institute of Scientific and Technical Information of China (English)

    叶群山; 吴少鹏; 陈筝; 刘至飞

    2008-01-01

    Rheological characteristics of fiber-modified asphalt mixture were investigated.Cellulous fiber,polyester fiber and mineral fiber were used as additives for asphalt mixture,and the dosages were 0.3%,0.3%,0.4%,respectively.Dynamic modulus test using superpave simple performance tester(SPT) was adopted to study the dynamic modulus and phase angle for the control mixture and fiber-modified ones at various temperatures and frequencies.Test results show that the rheological properties can be improved significantly by the addition of various fibers.The dynamic modulus increases with the increase of frequency,and the phase angle decreases with the increase of frequency.When various fibers are used,the dynamic modulus increases and phase angle decreases at each frequency.This indicates that the stiffness and the elastic portion of fiber-modified asphalt mixtures can be enhanced when various fibers are used,which results in the change of viscoelastic properties of mixtures.The creep test results show that the total strain and the permanent strain of asphalt mixtures during load-unload cycle can be significantly reduced,which results in the improvement of resistance to permanent deformation for asphalt mixtures containing various fiber additives.The Burgers model can be employed effectively to illustrate the rheological properties of fiber modified asphalt mixtures.

  15. Asphalt wear and pollution transport

    Energy Technology Data Exchange (ETDEWEB)

    Lindgren, Asa [Division of Traffic Engineering, Lulea University of Technology Lulea (Sweden)

    1996-09-06

    Studded tires cause extensive wear of road surfaces during winter producing small particles. Besides transporting different adsorbed pollutants these particles also discharge metal ions by their own natural content. The major part (95%) of the asphalt is composed of stone fractions. The rest consists mainly of bitumen, which contains trace quantities of metals. Laboratory studies in this study have demonstrated different adsorbing properties of metal ions, as well as differences in adsorption when comparing stone materials. Two stone materials, a gabbro and a porphyry, have been tested for their adsorption properties concerning Pb, Cu, Zn and Cd. The gabbro showed better adsorption capacity than the porphyry. Gabbro has coarser grains, it is softer, and also has a higher content of most metals compared to the porphyry. In all tests lead and copper are more adsorbed than zinc and cadmium. All metal ions are released at about the same pH ({approx}4)

  16. The reinforcement and healing of asphalt mastic mixtures by rejuvenator encapsulation in alginate compartmented fibres

    Science.gov (United States)

    Tabaković, A.; Post, W.; Cantero, D.; Copuroglu, O.; Garcia, S. J.; Schlangen, E.

    2016-08-01

    This paper explores the potential use of compartmented alginate fibres as a new method of incorporating rejuvenators into asphalt pavement mixtures. The compartmented fibres are employed to locally distribute the rejuvenator and to overcome the problems associated with spherical capsules and hollow fibres. The work presents proof of concept of the encapsulation process which involved embedding the fibres into the asphalt mastic mixture and the survival rate of fibres in the asphalt mixture. To prove the effectiveness of the alginate as a rejuvenator encapsulating material and to demonstrate its ability survive asphalt production process, the fibres containing the rejuvenator were prepared and subjected to thermogravimetric analysis and uniaxial tensile test. The test results demonstrated that fibres have suitable thermal and mechanical strength to survive the asphalt mixing and compaction process. The CT scan of an asphalt mortar mix containing fibres demonstrated that fibres are present in the mix in their full length, undamaged, providing confirmation that the fibres survived the asphalt production process. In order to investigate the fibres physiological properties and ability to release the rejuvenator into cracks in the asphalt mastic, the environmental scanning electron microscope and optical microscope analysis were employed. To prove its success as an asphalt healing system, compartmented alginate fibres containing rejuvenator were embedded in asphalt mastic mix. The three point bend tests were performed on the asphalt mastic test samples and the degree to which the samples began to self-heal in response was measured and quantified. The research findings indicate that alginate fibres present a promising new approach for the development of self-healing asphalt pavement systems.

  17. Polymer Blends Modified Asphalt

    Institute of Scientific and Technical Information of China (English)

    WANG YunPu; LI YuFeng; GAO XiaoHui; WANG RongMin

    2001-01-01

    @@ Asphalt is an important low-cost thermo-plastic material which is widely used for construction, in particular as road-paving. Therefore it is exposed to a wide range of load and weather conditions. Increasing traffic factors, such as heavier loads, higher traffic volume and higher tire pressure demand higher performance pavements. However, this kind of materials does not have good mechanical properties because it is hard and brittle in cold weather, and soft and fluid in a hot environment.

  18. Modeling Recycling Asphalt Pavement Processing Technologies in Asphalt Mixing Plants

    OpenAIRE

    Simonas Tamaliūnas; Henrikas Sivilevičius

    2011-01-01

    The article presents reclaimed asphalt pavement (RAP) processing technologies and equipment models used in the asphalt mixing plant (AMP). The schematic model indicating all possible ways to process RAP in AMP is shown. The model calculating the needed temperature of mineral materials used for heating RAP is given and an example of such calculation is provided.Article in Lithuanian

  19. Modeling Recycling Asphalt Pavement Processing Technologies in Asphalt Mixing Plants

    Directory of Open Access Journals (Sweden)

    Simonas Tamaliūnas

    2011-04-01

    Full Text Available The article presents reclaimed asphalt pavement (RAP processing technologies and equipment models used in the asphalt mixing plant (AMP. The schematic model indicating all possible ways to process RAP in AMP is shown. The model calculating the needed temperature of mineral materials used for heating RAP is given and an example of such calculation is provided.Article in Lithuanian

  20. Dead sea asphalts: historical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Nissenbaum, A.

    1978-05-01

    Asphalts are present in the Dead Sea basin in three forms: (1) huge blocks, up to 100 tons in weight, composed of extremely pure (>99.99%) solid asphalt occasionally found floating on the lake, (2) veins, seepages, and cavity and fissure fillings in Lower Cretaceous to Holocene rocks, and (3) ozocerite veins on the eastern shore of the lake. Dead Sea asphalts probably have been documented over a longer period of time than any other hydrocarbon deposit--from antiquity to the 19th century. Major uses of asphalt from the Dead Sea have been as an ingredient in the embalming process, for medicinal purposes, for fumigation, and for agriculture. The first known war for control of a hydrocarbon deposit was in the Dead Sea area in 312 B.C. between the Seleucid Syrians and the Nabatean Arabs who lived around the lake. Surface manifestations of asphalt are linked closely to tectonic activity. In the lake itself, the asphalt is associated with diapirs During certain historic periods, tectonic and diapiric activity caused frequent liberation to the Dead Sea surface of semiliquid asphalt associated with large amounts of hydrogen sulfide gas. When the tectonic activity was attenuated, as in the 19th and 20th centuries, the rate of asphalt seepage to the bottom sediments of the Dead Sea was much slower and the asphalt solidified on the lake bottom. The release of asphalt to the surface became much more sporadic, and may have resulted in part from earthquakes. Thus, future asphalt prospecting in the Dead Sea area should be conducted along the boundaries of diapirs or their associated faults.

  1. 天然沥青改性沥青的表面自由能分析%Surface free energy analysis of asphalt modified with natural asphalt

    Institute of Scientific and Technical Information of China (English)

    马峰; 郝景贤; 傅珍; 汪立龙; 汪林兵

    2015-01-01

    In order to accurately evaluate the adhesion of asphalt modified with natural asphalt and aggregate,the contact angles of three liquids on the sample surface of asphalt modified with natural asphalt were measured based on sessile drop method.According to the theory of surface physical chemistry,the measuring method of polar component and dispersion component for asphalt surface free energy under the condition of room temperature was determined.The surface free energies of base asphalt and asphalts modified with different dosages of natural asphalt were calculated.The relationship between asphalt surface free energy and asphalt-aggregate adhesion grade was analyzed based on the test result by using water-boiling method.Test result shows that the surface free energies of 70 # grade A base asphalt and asphalt modified with 8% natural asphalt are 10.60,18.60 mJ ·m-2 respectively,so the surface free energy of asphalt modified with natural asphalt increases distinctly with the addition of natural asphalt.There is a good correlation between asphalt-aggregate adhesion and the surface free energy of asphalt calculated by contact angle method.The natural asphalt contains higher polar functional groups such as O, S and N etc.High contents of asphaltene and net structure can absorb the light components of base asphalt such as saturates,aromatics.The increase of surface free energy for asphalt modified with natural asphalt is attributed to the polar functional groups and the absorbing functions. 4 tabs,4 figs,23 refs.%为了准确评价天然沥青改性沥青与集料的粘附性能,采用座滴法测定了3种液体在天然沥青改性沥青试样表面的接触角,基于表面物理化学理论,确定了室温条件下沥青表面自由能极性分量和色散分量的测定方法,计算了基质沥青和不同掺量天然沥青改性沥青的表面自由能。结合水煮法试验结果,分析了沥青结合料表面自由能与沥青-集料粘附性等级的

  2. USE OF CRUMB RUBBER FROM USED CAR TIRES IN MINERAL ASPHALT MIXES

    Directory of Open Access Journals (Sweden)

    Andrzej Plewa

    2014-11-01

    Full Text Available With the development of the automotive industry the disposal of used tires is constantly growing problem. Storage of waste rubber is associated with a very long period of decomposition of rubber in the natural conditions. Simultaneously new technologies are developed every year, which in the future may significantly promote recycling of this type of materials. The crumb rubbery modification of the road bitumen is the one of the environmentally safe solutions of rubbery decomposition. Improvement of resistance of the crumb rubbery modification of the road asphalt mixtures is the very important ecological aspect of the future. The article presents the results of research on the fatigue life resistance of asphalt concretes AC16P and AC22P with asphalt-rubber binders. The above analyses have been based on the results of tests of fatigue life of mineral-rubber-asphalt mixes determined by the method of prismatic four-point bending (4PB-PR. Mineral-rubber -asphalt mixes have been diversified according to the amount of the additive of rubber fines in asphalt-rubber binder. On the basis of the test results have been proven improvements functional properties mineral-rubber-asphalt mixes compared with mineral-asphalt mixes with unmodified asphalt.

  3. Polyurethane synthesis reactions in asphalts

    Energy Technology Data Exchange (ETDEWEB)

    Bukowski, A.; Gretkiewicz, J.

    1982-04-01

    A series of asphalt-polyurethane composites was prepared by means of polyurethane synthesis in asphalt and carried out in melt. The applied materials were asphalts of differentiated group components content, polyester polyols of chain structure from linear to strongly branched, 2,4-tolylene diisocyanate, 4,4-methylenebis(phenyl isocyanate), and tinorganic catalyst. The asphalt components react with isocyanates to a minimal degree. The influence of the applied substrates, temperature, and polyurethane content in the system on the basic kinetic relations characterizing the process is presented. Polyurethane synthesis in asphalts does not differ in a fundamental way from the obtaining of polyurethanes, especially when their content in the composition is significant, 20 wt% and more.

  4. Effects of Fibers on the Dynamic Properties of Asphalt Mixtures

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The dynamic characteristics of fiber-modified asphalt mixture were investigated. Cellulose fiber, polyester fiber and mineral fiber were used as additives for asphalt mixture, and the dosage was 0.3%, 0.3%,0.4%, respectively. Dynamic modulus test using SuperPave simple performance tester (SPT) was conducted to study the dynamic modulus (E*) and phase angle (δ) for the control asphalt mixture and fiber-modified ones at various temperatures and frequencies. Experimental results show that all fiber-modified asphalt mixtures have higher dynamic modulus compared with control mixture. The dynamic modulus master curves of each type of asphalt mixtures are determined based on nonlinear least square regression in accordance with the timetemperature superposition theory at a control temperature (21.1 ℃). The fatigue parameter E*×sinδ and rutting parameter E*/sinδ of asphalt mixture are adopted to study the fatigue and rutting-resistance properties, and experimental results indicate that such properties can be improved by fiber additives.

  5. Aqueous leaching of polycyclic aromatic hydrocarbons from bitumen and asphalt.

    Science.gov (United States)

    Brandt, H C; de Groot, P C

    2001-12-01

    The application of bitumen in, e.g. asphalt roads, roofs and hydraulic applications will lead to the leaching of compounds from the bitumen/asphalt into the environment. Because polycyclic aromatic hydrocarbons (PAHs) are present in bitumen, static and dynamic leach tests have been performed to study the leaching behaviour of this class of compounds. Nine petroleum bitumens covering a representative range of commercially available products and one asphalt made from one of the bitumens have been tested in a static leach test. The asphalt has been also subjected to a dynamic leach test. The main conclusions are that a 30h dynamic leach test is sufficient to determine the equilibrium concentration that will be reached after bitumen or asphalt has been in contact with the water for more than 3-6 days. As an alternative to performing a leach test, this concentration can be calculated from the PAH concentrations in the bitumen, and their distribution coefficients, as calculated here, or from their aqueous solubilities. The equilibrium PAH concentrations in the leach water from bitumens stay well below the surface water limits that exist in several EEC-countries and are also more than an order of magnitude lower than the current EEC limits for potable water.

  6. Dynamic Mechanical Characterizations and Road Performances of Flame Retardant Asphalt Mortars and Concretes

    Institute of Scientific and Technical Information of China (English)

    QIN Xiantao; ZHU Siyue; LI Zuzhong; CHEN Shuanfa

    2015-01-01

    To research the dynamic mechanical properties and road performances of flame retardant asphalt mortars and mixtures, four different asphalt mortars/mixtures were prepared: a reference group and three asphalt mortars/mixtures containing composite lfame retardant materials (M-FRs) of different proportions. Temperature sweep, frequency sweep, repeated creep test, force ductility test and bending beam rheological test were carried out to research the dynamic mechanical properties of asphalt mortars containing M-FRs; wheel-tracking test, low-temperature bending test and freeze-thaw split test were used to study the road performances of asphalt mixtures containing M-FRs. The results show that high-temperature performances of the three lfame retardant asphalt mortars improve greatly, while low-temperature cracking resistances decline. Both high-temperature performances and water stabilities of asphalt mixtures containing M-FRs are quite good and exceed the speciifcation requirements. However, their low-temperature performances decline in different degrees. In summary, besides their good lfame retardancy, the lfame retardant asphalt mortars and mixtures also exhibit acceptable road performance.

  7. Building America Case Study: Field Testing an Unvented Roof with Asphalt Shingles in a Cold Climate, Boilingbrook, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    2015-09-01

    Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a 'control' vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except the vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a 'diffusion vent' detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).

  8. Test on Dynamic Response of Flexible Base Asphalt Pavement%柔性基层沥青路面动力响应试槽试验

    Institute of Scientific and Technical Information of China (English)

    李起伟; 黎晓; 梁乃兴

    2012-01-01

    根据室内试槽柔性基层沥青路面结构的重复加载试验,总结了路用电阻应变片的选择依据和黏贴工艺,对比分析了压路机压实方式对应变片存活率的影响;利用惠斯登电桥电路测试了柔性基层沥青路面的动力响应,并与数值计算进行对比.研究表明:路用电阻应变片栅长应大于80 mm,并与集料的最大公称粒径相关;电阻应变片在压路机静压的方式下有较理想的存活率,而在强振作用下却极难存活;在移动荷载作用下沥青面层底部横向应变交替出现拉、压应变,其最大值比层状弹性体系模型计算值小.%According to repeated load test of flexible base asphalt pavement, the structure is built in the indoor pit. The principle of choosing resistance strain gauges and the surface-sticking process of gauge was summarized; the survival rate of strain gauge based on the comparison of road roller' s compaction mode strong vibration or static pressure was discussed. The data of time-history curves was collected through the Wheatstone Bridge with the numerical calculation comparative study. The detection results show; the gate length of resistance strain gauge should not be less than 80mm, which is related to nominal maximum size of aggregate. Gauges' survival rate is affected by different compaction model, which is much lower under the strong vibration model. Also the response of. strain in layer bottom under the dynamic load of moving vehicle is more complex than that in static situation. However, the current pavement structure design method needs transforming from static model to dynamic load model.

  9. Application of minerals residues in the asphalt composition; Aplicacao de residuos minerais na composicao do asfalto

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Roberto Carlos da C.; Seidl, Peter Rudolf [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica; Correia, Julio Cesar Guedes [Centro de Tecnologia Mineral - CETEM, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    The performance of asphalt pavements depends mainly on the properties of their constituents: mineral aggregates and asphalt cement. The mineral aggregate represents about 95% in weight of asphalt mixtures having a significant influence on the properties and performance of these mixtures. Asphalt cement (CAP) corresponds to the smaller fraction but it is mainly responsible for adsorption on the mineral aggregates. The objective of this study was to evaluate the interaction between different CAPs with residues from granite saw wills in place of mineral aggregates that run up costs with extraction and processing in asphalt production. This way asphalt production costs as well as the environmental problems that are caused by mineral residue are reduced. Five different asphalt cements, referred to as A, B, C, D and E, and a granite residue were used in this work. The results indicated that the residue strongly absorbs all the CAPs that were studied; particularly CAP A, which is considered the most adequate for the production of asphalt from this residue. Preliminary tests this indicate that asphalt production can use mineral residues instead of mineral aggregates in its composition. (author)

  10. Preparation, Characterization and Hot Storage Stability of Asphalt Modified by Waste Polyethylene Packaging

    Institute of Scientific and Technical Information of China (English)

    Changqing Fang; Ying Zhang; Qian yu; Xing Zhou; Dagang Guo; Ruien Yu; Min Zhang

    2013-01-01

    Waste polyethylene packaging (WPE) was used to modify asphalt,and hot storage stability of the modified asphalt was studied in this paper.The morphological change and component loss of WPE modified asphalt were characterized by fluorescence microscopy,Fourier transform infrared spectroscopy (FT-IR),differential scanning calorimetry (DSC),thermogravimetry (TG) and isolation testing.In addition,the mechanism of the hot storage stability of WPE modified asphalt was discussed.The results showed that the modification of asphalt with WPE was a physical process.It was found that the filament or partly network-like structure formed in the modified asphalt system was beneficial to improving the hot storage stability.Moreover,the addition of WPE resulted in a decrease in both the light components volatilization and the macromolecules decomposition of asphalt.It was demonstrated that when the content of WPE in matrix asphalt was less than 10 wt%,the service performances of modified asphalt could be better.

  11. The Utilization of Graphene Oxide in Traditional Construction Materials: Asphalt

    Directory of Open Access Journals (Sweden)

    Wenbo Zeng

    2017-01-01

    Full Text Available In the advanced research fields of solar cell and energy storing materials, graphene and graphene oxide (GO are two of the most promising materials due to their high specific surface area, and excellent electrical and physical properties. However, they was seldom studied in the traditional materials because of their high cost. Nowadays, graphene and GO are much cheaper than before with the development of production technologies, which provides the possibility of using these extraordinary materials in the traditional construction industry. In this paper, GO was selected as a nano-material to modify two different asphalts. Then a thin film oven test and a pressure aging vessel test were applied to simulate the aging of GO-modified asphalts. After thermal aging, basic physical properties (softening point and penetration were tested for the samples which were introduced at different mass ratios of GO (1% and 3% to asphalt. In addition, rheological properties were tested to investigate how GO could influence the asphalts by dynamic shearing rheometer tests. Finally, some interesting findings and potential utilization (warm mixing and flame retardants of GO in asphalt pavement construction were explained.

  12. Simulation tests to assess occupational exposure to airborne asbestos from artificially weathered asphalt-based roofing products.

    Science.gov (United States)

    Sheehan, Patrick; Mowat, Fionna; Weidling, Ryan; Floyd, Mark

    2010-11-01

    Historically, asbestos-containing roof cements and coatings were widely used for patching and repairing leaks. Although fiber releases from these materials when newly applied have been studied, there are virtually no useful data on airborne asbestos fiber concentrations associated with the repair or removal of weathered roof coatings and cements, as most studies involve complete tear-out of old roofs, rather than only limited removal of the roof coating or cement during a repair job. This study was undertaken to estimate potential chrysotile asbestos fiber exposures specific to these types of roofing products following artificially enhanced weathering. Roof panels coated with plastic roof cement and fibered roof coating were subjected to intense solar radiation and daily simulated precipitation events for 1 year and then scraped to remove the weathered materials to assess chrysotile fiber release and potential worker exposures. Analysis of measured fiber concentrations for hand scraping of the weathered products showed 8-h time-weighted average concentrations that were well below the current Occupational Safety and Health Administration permissible exposure limit for asbestos. There was, however, visibly more dust and a few more fibers collected during the hand scraping of weathered products compared to the cured products previously tested. There was a notable difference between fibers released from weathered and cured roofing products. In weathered samples, a large fraction of chrysotile fibers contained low concentrations of or essentially no magnesium and did not meet the spectral, mineralogical, or morphological definitions of chrysotile asbestos. The extent of magnesium leaching from chrysotile fibers is of interest because several researchers have reported that magnesium-depleted chrysotile fibers are less toxic and produce fewer mesothelial tumors in animal studies than normal chrysotile fibers.

  13. Polymer Blends Modified Asphalt

    Institute of Scientific and Technical Information of China (English)

    WANG; YunPu

    2001-01-01

    Asphalt is an important low-cost thermo-plastic material which is widely used for construction, in particular as road-paving. Therefore it is exposed to a wide range of load and weather conditions. Increasing traffic factors, such as heavier loads, higher traffic volume and higher tire pressure demand higher performance pavements. However, this kind of materials does not have good mechanical properties because it is hard and brittle in cold weather, and soft and fluid in a hot environment.  ……

  14. Test on CRTSⅡ type slab ballastless track cement-emulsified asphalt mortar%CRTSⅡ型无砟轨道水泥乳化沥青砂浆试验研究

    Institute of Scientific and Technical Information of China (English)

    张惠元

    2012-01-01

    Taking the practice of CRTSⅡ type slab ballastless track construction of Beijing-Shanghai high-speed railway three section for basis,combining with its pre-production test analysis and its specific practical application,focusing on carried out comparative test and analysis on the raw material types and dosage of cement-emulsified asphalt mortar and construction technology and other key influence factors,so as to lay foundation for the science preparation and construction of cement-emulsified asphalt mortar.%以京沪高速铁路三标CRTSⅡ型无砟轨道施工的实践为基础,结合其生产前的试验分析及其具体的实践应用,重点对水泥乳化沥青砂浆的原材料种类及其用量和施工工艺等关键影响因素开展试验对比分析,从而为水泥乳化沥青砂浆的科学制备和施工奠定了基础。

  15. Engineering characterisation of epoxidized natural rubber-modified hot-mix asphalt

    Science.gov (United States)

    Al-Mansob, Ramez A.; Ismail, Amiruddin; Yusoff, Nur Izzi Md.; Rahmat, Riza Atiq O. K.; Borhan, Muhamad Nazri; Albrka, Shaban Ismael; Azhari, Che Husna; Karim, Mohamed Rehan

    2017-01-01

    Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the performance characteristics of epoxidized natural rubber (ENR)-modified hot-mix asphalt. Tests were conducted using ENR–asphalt mixes prepared using the wet process. Mechanical testing on the ENR–asphalt mixes showed that the resilient modulus of the mixes was greatly affected by testing temperature and frequency. On the other hand, although rutting performance decreased at high temperatures because of the increased elasticity of the ENR–asphalt mixes, fatigue performance improved at intermediate temperatures as compared to the base mix. However, durability tests indicated that the ENR–asphalt mixes were slightly susceptible to the presence of moisture. In conclusion, the performance of asphalt pavement can be enhanced by incorporating ENR as a modifier to counter major road distress. PMID:28182724

  16. Engineering characterisation of epoxidized natural rubber-modified hot-mix asphalt.

    Science.gov (United States)

    Al-Mansob, Ramez A; Ismail, Amiruddin; Yusoff, Nur Izzi Md; Rahmat, Riza Atiq O K; Borhan, Muhamad Nazri; Albrka, Shaban Ismael; Azhari, Che Husna; Karim, Mohamed Rehan

    2017-01-01

    Road distress results in high maintenance costs. However, increased understandings of asphalt behaviour and properties coupled with technological developments have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, polymers have become extremely popular as modifiers to improve the performance of the asphalt mix. This study investigates the performance characteristics of epoxidized natural rubber (ENR)-modified hot-mix asphalt. Tests were conducted using ENR-asphalt mixes prepared using the wet process. Mechanical testing on the ENR-asphalt mixes showed that the resilient modulus of the mixes was greatly affected by testing temperature and frequency. On the other hand, although rutting performance decreased at high temperatures because of the increased elasticity of the ENR-asphalt mixes, fatigue performance improved at intermediate temperatures as compared to the base mix. However, durability tests indicated that the ENR-asphalt mixes were slightly susceptible to the presence of moisture. In conclusion, the performance of asphalt pavement can be enhanced by incorporating ENR as a modifier to counter major road distress.

  17. Feasibility of using 100% Recycled Asphalt Pavement mixtures for road construction

    Science.gov (United States)

    Carlson, Russell Edgar, IV

    Recycled Asphalt Pavement (RAP) is the largest recycled good in the United States and 80 million tons are recycled yearly, saving taxpayers about $1.5 billion dollars. This paper explores the possibility of utilizing 100% RAP materials in asphalt pavement. Asphalt mixtures are produced at 135°C in a typical asphalt plant. However, at 135°C, not all binder from RAP materials may not become effective for coating aggregates. The main objective of the study is to determine the amount of effective binder available from RAP in the asphalt plant. The 100% RAP mixes have aged binder that can alter mix designs and interaction with virgin binder. In this study, to determine low temperature cracking resistance and fatigue performance, samples were prepared using a 100% RAP mix with no virgin binder and a 100% RAP mix with virgin asphalt binder to achieve the optimum binder content of the mix. Second, to determine the effectiveness of binder from RAP materials, compaction tests were performed by heating RAP materials at various temperatures. It was found that 100% RAP mixes cannot be feasible for field use if additional virgin binder is added to reach the optimum asphalt content. Based on limited test results, the low temperature grade was not within proper limits but the beam fatigue testing results were acceptable. Based on compaction test results, additional heating is needed to increase the effectiveness of asphalt binder from RAP materials.

  18. Mechanical evaluation of asphalt-aggregate mixtures prepared with fly ash as a filler replacement

    Energy Technology Data Exchange (ETDEWEB)

    Tapkin, T. [Anadolu Univ., Eskisehir (Turkey). Dept. of Civil Engineering

    2008-01-15

    This paper examined methods of introducing fly ash waste products as a filler in asphalt concrete mixtures. A literature review of studies involving fly ash and asphalts was conducted. The effect of fly ash filler replacements on the mechanical properties of asphalt-aggregate mixtures was investigated. A dense bituminous calcareous aggregate was used as a reference mixture for a series of tests. Three types of fly ash were investigated, notably (1) portland cement; (2) lime; and (3) control specimens. Changes in elastic strain, elastic modulus, and permanent strain properties of the asphalt mixtures were determined through a series of fatigue tests. The behaviour of the asphalt concrete pavements were analyzed under applied loads. Results of the tests showed that the fatigue life of the fly ash specimens was higher than the calcareous aggregate specimens. It was concluded that fly ash can used as a filler replacement for dense-graded wearing courses. 35 refs., 17 tabs., 8 figs.

  19. Assessment of Water Quality of Runoff from Sealed Asphalt Surfaces

    Science.gov (United States)

    This report discusses the results of runoff tests from recently-sealed asphalt surfaces conducted at EPA's Urban Watershed Research Facility (UWRF) in Edison, New Jersey. Both bench-scale panels and full-scale test plots were evaluated. Full-scale tests were performed on an asp...

  20. 75 FR 12988 - National Emission Standards for Hazardous Air Pollutants for Area Sources: Asphalt Processing and...

    Science.gov (United States)

    2010-03-18

    ... Sources: Asphalt Processing and Asphalt Roofing Manufacturing; Technical Correction AGENCY: Environmental... the asphalt processing and asphalt roofing manufacturing area source category (74 FR 63236). Following... the asphalt processing and asphalt roofing manufacturing area source category on December 2, 2009...

  1. Curing Behavior of Epoxy Asphalt

    Institute of Scientific and Technical Information of China (English)

    YU Jianying; CONG Peiliang; WU Shaopeng; CHENG Songbo

    2009-01-01

    The curing process of epoxy asphalt was analyzed by Fourier transform infrared (FT-IR)spectroscopy.Effect of curing temperature on viscosity of epoxy asphalt,and changes of mechanical properties with curing time were investigated.The evolution of concentration of epoxy band was followed as a function of the applied curing process.The experimental results indicate that the curing reaction rate of epoxy asphalt is invariable before 70 min at 120℃,and it decreases when curing time exceeds 70 min.The viscosity of epoxy asphalt increases slowly with curing time at initial curing stage.But it increases quickly after initial curing stage and the initial curing time decreases as the curing temperature increases.The tensile strength increases slowly at incipient curing stage and increases rapidly when curing time is form 20 min to 70 min.The elongation at break shows a decrease with curing time,but it exceeds 200%after cured.

  2. Investigation of modified asphalt concrete

    Science.gov (United States)

    Zimich, Vita

    2016-01-01

    Currently the problem of improving the asphalt quality is very urgent. It is used primarily as topcoats exposed to the greatest relative to the other layers of the road, dynamic load - impact and shear. The number of cars on the road, the speed of their movement, as well as the traffic intensity increase day by day. We have to upgrade motor roads, which entails a huge cost. World experience shows that the issue is urgent not only in Russia, but also in many countries in Europe, USA and Asia. Thus, the subject of research is the resistance of asphalt concrete to water and its influence on the strength of the material at different temperatures, and resistance of pavement to deformation. It is appropriate to search for new modifiers for asphaltic binder and mineral additives for asphalt mix to form in complex the skeleton of the future asphalt concrete, resistant to atmospheric condensation, soil characteristics of the road construction area, as well as the growing road transport load. The important task of the work is searching special modifying additives for bitumen binder and asphalt mixture as a whole, which will improve the quality of highways, increasing the period between repairs. The methods described in the normative-technical documentation were used for the research. The conducted research allowed reducing the frequency of road maintenance for 7 years, increasing it from 17 to 25 years.

  3. Asphalt emulsion sealing of uranium mill tailings. 1980 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, J.N.; Koehmstedt, P.L; Esterl, D.J.; Freeman, H.D.; Buelt, J.L.; Nelson, D.A.; Elmore, M.R.

    1981-05-01

    Studies of asphalt emulsion sealants conducted by the Pacific Northwest Laboratory have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to near background levels. Field tests at the tailings pile in Grand Junction, Colorado, confirmed that an 8-cm admix seal containing 22 wt% asphalt could be effectively applied with a cold-mix paver. Other techniques were successfully tested, including a soil stabilizer and a hot, rubberized asphalt seal that was applied with a distributor truck. After the seals were applied and compacted, overburden was applied over the seal to protect the seal from ultraviolet degradation.

  4. Deformation Parameters and Fatigue of the Recycled Asphalt Mixtures

    Science.gov (United States)

    Šrámek, Juraj

    2015-12-01

    The deformational properties of asphalt mixtures measured by dynamic methods and fatigue allow a design the road to suit the expected traffic load. Quality of mixtures is also expressed by the resistance to permanent deformation. Complex modulus of stiffness and fatigue can reliably characterize the proposed mixture of asphalt pavement. The complex modulus (E*) measurement of asphalt mixtures are carried out in laboratory of Department of Construction Management at University of Žilina by two-point bending test method on trapezoid-shaped samples. Today, the fatigue is verified on trapezoid-shaped samples and is assessed by proportional strain at 1 million cycles (ɛ6). The test equipment and software is used to evaluate fatigue and deformation characteristics.

  5. Performance evaluation of high modulus asphalt concrete mixes

    Science.gov (United States)

    Haritonovs, V.; Tihonovs, J.; Zaumanis, M.

    2016-04-01

    Dolomite is one of the most available sedimentary rocks in the territory of Latvia. Dolomite quarries contain about 1000 million tons of this material. However, according to Latvian Road Specifications, this dolomite cannot be used for average and high intensity roads because of its low quality (mainly, LA index). Therefore, mostly imported magmatic rocks (granite, diabase, gabbro, basalt) or imported dolomite are used which makes asphalt expensive. However, practical experience shows that even with these high quality materials roads exhibit rutting, fatigue and thermal cracks. The aim of the research is to develop a high performance asphalt concrete for base and binder courses using only locally available aggregates. In order to achieve resistance against deformations at a high ambient temperature, a hard grade binder was used. Workability, fatigue and thermal cracking resistance, as well as sufficient water resistance is achieved by low porosity (3-5%) and higher binder content compared to traditional asphalt mixtures. The design of the asphalt includes a combination of empirical and performance based tests, which in laboratory circumstances allow simulating traffic and environmental loads. High performance AC 16 base asphalt concrete was created using local dolomite aggregate with polymer modified (PMB 10/40-65) and hard grade (B20/30) bitumen. The mixtures were specified based on fundamental properties in accordance to EN 13108-1 standard.

  6. Use of X-ray diffraction in assessing the aging pattern of asphalt fractions

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, M.N.; Ali, M.F.; Shirokoff, J. [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Chemistry and The Research Institute

    2002-01-01

    The X-ray diffraction (XRD) method was employed to investigate and compare some of the crystallite parameters and aromaticity of asphaltenes obtained from fresh and aged Arabian asphalts, procured from Ras Tanura (RT) and Kuwait (KW) refineries. A new crystallite parameters in the polar aromatics, naphthene aromatics and saturate fractions of these Arabian asphalts were also determined. The results obtained by XRD method for both the types of asphaltenes and other fractions were evaluated and compared. Significant differences were observed between the structure and the aging patterns of fresh and aged asphaltenes of RT and KW asphalt. The results indicate that the source and chemistry of asphalt are responsible for the aging behavior of its components. The rolling thin-film oven and the pressurized aging vessels tests were used to simulate asphalt aging in this research. 21 refs., 5 figs., 4 tabs.

  7. ENHANCING ASPHALT RHEOLOGICAL BEHAVIOR AND AGING SUSCEPTIBILITY USING BIO-CHAR AND NANO-CLAY

    Directory of Open Access Journals (Sweden)

    Renaldo C. Walters

    2014-01-01

    Full Text Available The life expectancy of Asphalt Binder (AB has been negatively impacted by the harsh bombardment of UV rays. UV rays cause asphalt to oxidize faster, which results in deterioration of asphalt rheological characteristics that can lead to pavement distresses. This study investigates the impact of bio-char and nano-clay of asphalt rheological properties. Two nano scale materials were used for this study were nano-clay and bio-char. Nano-clay (Cloisite 30B is a naturally occurring inorganic mineral. Bio-char is the waste product from bio-binder production. Bio-binder is produced from swine manure using a thermochemical conversion process. This process is then followed by a filtration procedure where the bio-char is produced. Chemical and physical properties of bio-char showed a significant presence of carbon which could in turn enhance asphalt flow properties and reduce the rate of asphalt oxidation. In this study several mixtures are designed and evaluated using Rotational Viscometer testing (RV and X-Ray Diffraction (XRD. Nano-clay is blended at 2 and 4% by weight, with and without bio-binder (5% by weight of dry mass. Bio-char is grinded to nano scale and added to the virgin asphalt binder (PG 64-22 at 2, 5 and 10% by weight. The study results showed that introduction of nano-clay could be effective in reducing temperature susceptibility of asphalt binder.

  8. The Study of Water Stability for SBS and Polyacrylate Composite Modified Asphalt Mixture

    Directory of Open Access Journals (Sweden)

    HU Qiusheng

    2014-09-01

    Full Text Available Polyacrylate (Polyacrylate, called PAE is a kind of thermoplastic polymer latex, which is easy to form a waterproof membrane and has greater adhesion ,always be used in concrete to enhance its ability to resist water corrosion.SBS is an inorganic modifier for modified asphalt mixture will help to improve the high and low temperature stability and other road performance, ect.However,its ability to enhanced asphalt mixture’s resistance for water damage is not obvious. In order to research the two composite modified asphalt mixture’s resistance effects to water damage , the Marshall Stability Test and Fort Kentucky Flooding Scattering Experiments were used on asphalt mixtures, SBS modified asphalt mixture and composite modified asphalt mixture and the effect of different composite modified PAE content were studied. The results showed that: PAE can significantly improve the water stability of asphalt mixture, what’s more, with the increase use of PAE,the mass loss rate of asphalt mixture decreases steadily.

  9. Nanomaterials Applied in Asphalt Modification: A Review

    Institute of Scientific and Technical Information of China (English)

    Changqing Fang; Ruien Yu; Shaolong Liu; Yan Li

    2013-01-01

    Nanotechnology has been gradually penetrated into the field of asphalt modification.Seemingly magic effects of nanomaterials have now been brought to improve the performance of asphalt.To demonstrate many of the prospective applications,researchers have conducted a series of positive and effective efforts dealing with the preparation of modified asphalt to demonstrate the mechanism of modification and the resultant improvement in performance.In this review,various nanomaterials used in asphalt modification are initially presented,followed by the methods employed to modify the asphalt with these materials and finally the effects of nanomaterials on the performance of base asphalt are presented and the modification mechanisms are discussed.Based on the current research results,the influence of preparation process parameters on the compatibility of every phase in the modified asphalt and the stability of the modified asphalt system are described.Finally,the development trend of the topic field is projected.

  10. Rutting Prediction in Asphalt Pavement Based on Viscoelastic Theory

    Directory of Open Access Journals (Sweden)

    Nahi Mohammed Hadi

    2016-01-01

    Full Text Available Rutting is one of the most disturbing failures on the asphalt roads due to the interrupting it is caused to the drivers. Predicting of asphalt pavement rutting is essential tool leads to better asphalt mixture design. This work describes a method of predicting the behaviour of various asphalt pavement mixes and linking these to an accelerated performance testing. The objective of this study is to develop a finite element model based on viscoplastic theory for simulating the laboratory testing of asphalt mixes in Hamburg Wheel Rut Tester (HWRT for rutting. The creep parameters C1, C2 and C3 are developed from the triaxial repeated load creep test at 50°C and at a frequency of 1 Hz and the modulus of elasticity and Poisson’ s ratio determined at the same temperature. Viscoelastic model (creep model is adopted using a FE simulator (ANSYS in order to calculate the rutting for various mixes under a uniform loading pressure of 500 kPa. An eight-node with a three Degrees of Freedom (UX, UY, and UZ Element is used for the simulation. The creep model developed for HWRT tester was verified by comparing the predicted rut depths with the measured one and by comparing the rut depth with ABAQUS result from literature. Reasonable agreement can be obtained between the predicted rut depths and the measured one. Moreover, it is found that creep model parameter C1 and C3 have a strong relationship with rutting. It was clear that the parameter C1 strongly influences rutting than the parameter C3. Finally, it can be concluded that creep model based on finite element method can be used as an effective tool to analyse rutting of asphalt pavements.

  11. Sinopec Launches Shanghai Asphalt Sales Company

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Sinopec Shanghai Asphalt Sales Company was launched in Shanghai on September 22, marking Sinopec as the largest asphalt supplier in China integrated in famous brand,production, sales and research, and distribution network.This is another important initiative for Sinopec's asphalt segment, after Sinopec won the bid for construction of F 1 racing course, to grasp the market opportunities, further improve the product quality and the level of after-sales services, and further make its asphalt business larger and stronger.

  12. Floating asphalt blocks of the Dead Sea

    Energy Technology Data Exchange (ETDEWEB)

    Nissenbaum, A. (Weizmann Inst. of Science, Rehovot, Israel); Aizenshtat, Z.; Goldberg, M.

    1980-01-01

    Large blocks of mineral matter free (less than 0.1%) asphalt are occasionally found floating on the surface of the Dead Sea. Chemical, spectroscopic and isotopic data are given for the asphalt. The source of the asphalt is not accurately known, but presumably it represents mobilization of heavy viscous asphaltic masses at depth below the lake bottom into the floor of the lake. It may be released to the surface by earth tremors.

  13. VISCOELASTIC STRUCTURAL MODEL OF ASPHALT CONCRETE

    Directory of Open Access Journals (Sweden)

    V. Bogomolov

    2016-06-01

    Full Text Available The viscoelastic rheological model of asphalt concrete based on the generalized Kelvin model is offered. The mathematical model of asphalt concrete viscoelastic behavior that can be used for calculation of asphalt concrete upper layers of non-rigid pavements for strength and rutting has been developed. It has been proved that the structural model of Burgers does not fully meet all the requirements of the asphalt-concrete.

  14. Induction Healing of Porous Asphalt Concrete

    NARCIS (Netherlands)

    Liu, Q.

    2012-01-01

    Porous asphalt shows excellent performance in both noise reduction and water drainage. Although porous asphalt has these great qualities, its service life is much shorter (sometimes only half) compared to dense graded asphalt roads. Ravelling, which is the loss of aggregate particles from the surfac

  15. Characterization and thermal behavior of polymer-modified asphalt

    Directory of Open Access Journals (Sweden)

    Maria da Conceição Cavalcante Lucena

    2004-12-01

    Full Text Available A styrene-butadiene-styrene modified asphalt cement was characterized by infrared, differential scanning calorimetry, thermogravimetric analysis and empirical tests such as ring and ball softening point, penetration and elastic recovery. After aging in the rolling thin-film oven, the polymer-modified asphalt presented structural changes relating to oxidation of the material. The infrared spectra showed an increase in hydroxyl groups and the formation of carbonyl compounds and sulphoxides. The percentage of crystallized fraction calculated from differential scanning calorimetry was 0.41%. Thermogravimetric analyses in inert and oxidative atmospheres revealed distinct events during thermal decomposition; the initial activation energies were similar, but changed as the process evolved.

  16. Assessment of low temperature cracking in asphalt pavement mixes and rheological performance of asphalt binders

    Science.gov (United States)

    Sowah-Kuma, David

    Government spends a lot of money on the reconstruction and rehabilitation of road pavements in any given year due to various distresses and eventual failure. Low temperature (thermal) cracking, one of the main types of pavement distress, contributes partly to this economic loss, and comes about as a result of accumulated tensile strains exceeding the threshold tensile strain capacity of the pavement. This pavement distress leads to a drastic reduction of the pavement's service life and performance. In this study, the severity of low temperature (thermal) cracking on road pavements selected across the Province of Ontario and its predicted time to failure was assessed using the AASTHO Mechanistic-Empirical Pavement Design Guide (MEPDG) and AASHTOWARE(TM) software, with inputs such as creep compliance and tensile strength from laboratory test. Highway 400, K1, K2, Y1, Sasobit, Rediset LQ, and Rediset WMX were predicted to have a pavement in-service life above 15 years. Additionally, the rheological performance of the recovered asphalt binders was assessed using Superpave(TM) tests such as the dynamic shear rheometer (DSR) and bending beam rheometer (BBR). Further tests using modified standard protocols such as the extended bending beam rheometer (eBBR) (LS-308) test method and double-edge notched tension (DENT) test (LS-299) were employed to evaluate the failure properties associated with in service performance. The various rheological tests showed K1 to be the least susceptible to low temperature cracking compared to the remaining samples whiles Highway 24 will be highly susceptible to low temperature cracking. X-ray fluorescence (XRF) analysis was performed on the recovered asphalt binders to determine the presence of metals such as zinc (Zn) and molybdenum (Mo) believed to originate from waste engine oil, which is often added to asphalt binders. Finally, the severity of oxidative aging (hardening) of the recovered asphalt binders was also evaluated using the

  17. The improvement of pavement performance using asphalt rubber hot mixes

    OpenAIRE

    Pais, Jorge C.; Pereira, Paulo A. A.

    2007-01-01

    The need of a better pavement performance has led researchers to develop new road materials, mainly for the asphalt layers, where the modification of the asphalt is the main example. This modification usually forces the use of polymers and fibers and, more recently, the use of crumb rubber from ground tires, where the modified asphalt is known as asphalt rubber. This asphalt rubber used in asphalt mixtures produces a superior performance if compared to the asphalt mixtures with...

  18. Open Graded Asphalt Mixture Design for Environmentally Friendly Road

    Science.gov (United States)

    Setyawan, A.; Suryoto; Sumarsono, A.; Widyastuti, S.

    2017-02-01

    The road is an important infrastructure to support various economic development. By increasing the population, the constructions of road infrastructure are obviously required and cover more land use area, consequently narrowed the areas for water absorption into the land. Therefore, it is necessary to improve more environmentally friendly of road constructions, in this case is by using open graded asphalt. Open graded asphalt is the mixture of asphalt with low fine aggregate content to produce a high percentage of air voids, which expected to be able to absorb water into the land underneath. This observation uses laboratory experiment method. Materials that are used are natural gravel and the volcanic gravel, 60/70 asphalt penetration and stone dust filler. The tests performed for the samples are Marshall test, falling head water permeability, indirect tensile strength and unconfined compressive strength. The optimum bitumen content for each type of aggregate have been found to be 2.95% for natural gravel and 4.65% for volcanic gravel. Open graded asphalt porosity is 26.52% for natural gravel, whereas the volcanic gravel is 22.31%. The vertical and horizontal permeability for natural gravel are 1.25 cm/second and 0.92 cm/second, respectively. Whereas, for the volcanic gravel is 1.43 cm/second and 1.10 cm/second, respectively. Indirect tensile strength (ITS) value for natural gravel is 59.49 KPa whereas the volcanic gravel is 74.84 KPa. The unconfined compressive strength (UCS) value for natural gravel is 1070.63 KPa, whereas the volcanic gravel is 1120.69 KPa. It is concluded that the open graded porous asphalt is only compatible for low volume traffic road and need improvement to be able to be used as standard road.

  19. Performance of the heavy fraction of pyrolysis oil derived from waste printed circuit boards in modifying asphalt.

    Science.gov (United States)

    Yang, Fan; Sun, Shuiyu; Zhong, Sheng; Li, Shenyong; Wang, Yi; Wu, Jiaqi

    2013-09-15

    The focus of this research was the development of efficient and affordable asphalt modifiers. Pyrolysis oil was produced as a byproduct from the pyrolysis of waste printed circuit boards (WPCBs). The high boiling point fraction was separated from the pyrolysis oil through distillation and is referred to as the heavy fraction of pyrolysis oil (HFPO). The HFPO was tested as an asphalt modifier. Three asphalt modifiers were tested: HFPO; styrene-butadiene rubber (SBR); and HFPO + SBR (1:1). The physical properties and road performance of the three modified asphalts were measured and evaluated. The results have shown that when the amount of modifier was less than 10%, the HFPO modified asphalt had the highest softening point of the three. The dynamic stability (DS) and water resistance of the asphalt mixture with the HFPO modified asphalt was 10,161 cycles/mm and 87.2%, respectively. The DS was much larger than for the HFPO + SBR and SBR modified asphalt mixtures. These results indicate that using HFPO as an asphalt modifier has significant benefits not only for road engineering but also for resource recycling.

  20. Experimental evaluation on high temperature rheological properties of various fiber modified asphalt binders

    Institute of Scientific and Technical Information of China (English)

    陈筝; 吴少鹏; 朱祖煌; 刘杰胜

    2008-01-01

    High temperature rheological properties of fiber modified asphalt binders and impact of the type and content on such properties were studied.Three types of fiber,including polyester(PET),polyacrylonitrile(PAN) and cellulose(CEL),a control content(0%) and four levels of fiber content(2%,4%,6% and 8% by total asphalt binder mass) were used with asphalt binders.The high temperature rheological properties,consisting of complex modulus(G*) and phase angle δ,were measured using SHRP’s dynamic shear rheometer(DSR) between 46-82 ℃.Experimental results indicate that the changes of G* and tan δ of fiber modified asphalt binders with the increase of test temperature tend to slow down,and the temperature susceptibility is improved obviously compared to that of original asphalt binder.Fiber modification results in the increase of rutting parameter(G*/sin δ) at high temperatures,the decrease of temperature susceptibility,and further improved high temperature performance of asphalt binder.An excellent correlation exhibits between fiber content and high temperature performance of asphalt binder.Moreover,fiber type also has different influences on the improvement of G*/sin δ,G*/sin δ of PET and PAN fiber asphalt binders are both higher than that of CEL fiber,but G*/sin δ of CEL fiber is still higher than that of original asphalt.However,there is a critical fiber content when fibers start to interact with each other.Therefore,based on the critical fiber content and economic consideration,the optimum fiber contents for various fiber-modified asphalt binders are obtained.

  1. Hanford Permanent Isolation Barrier Program: Asphalt technology data and status report - FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Romine, R.A.; Zacher, A.H.

    1994-09-01

    The asphalt layer within the Hanford Permanent Isolation Barrier (HPIB) is an important component of the overall design. This layer provides a RCRA equivalent backup to the overlying earthen layers in the unlikely event that these layers are not able to reduce the infiltration rate to less than 0.05 cm/yr. There is only limited amount of information on using asphalt for a moisture infiltration barrier over the long times required by the HPIB. Therefore, a number of activities are under way, as part of the Barrier Development Program, to obtain data on the performance of asphalt as a moisture barrier in a buried environment over a 1000-year period. These activities include (1) determining RCRA equivalency, (2) measurement of physical properties, (3) measurement of aging characteristics, and (4) relationship to ancient asphalt analogs. During FY 1994 progress was made on all of these activities. Studies were conducted both in the laboratory and on the prototype barrier constructed over the 216-B-57 crib in the 200 East Area on the Hanford Site. This report presents results obtained from the asphalt technology tasks during FY 1994. Also included are updates to planned activities for asphalt analogs and monitoring the asphalt test pad near the prototype barrier. Measurements of hydraulic conductivity on the HMAC portion of the prototype barrier show that the asphalt layers easily meet the RCRA standard of 1 {times} 10{sup -7} cm/s. In-place measurements using a new field falling head technique show an average of 3.66 {times} 10{sup -8} cm/s, while cores taken from the north end of the prototype and measured in a laboratory setup averaged 1.29 {times} 10{sup -9} cm/s. Measurements made on the fluid applied asphalt membrane (polymer-modified asphalt) show an extremely low permeability of less than 1 {times} 10{sup -11} cm/s.

  2. Design tool for the thermal energy potential of asphalt pavements

    NARCIS (Netherlands)

    Loomans, M.G.L.C.; Oversloot, H.P.; Bondt, A. de; Jansen, R.; Rij, H. van

    2003-01-01

    This paper describes the development of a design tool for the calculation of the thermal energy potential of a so-called asphalt collector. Two types of numerical models have been developed and validated against experimental results from a full-scale test-site. The validation showed to be a tedious

  3. Mechanistic and Economical Characteristics of Asphalt Rubber Mixtures

    Directory of Open Access Journals (Sweden)

    Mena I. Souliman

    2016-01-01

    Full Text Available Load associated fatigue cracking is one of the major distress types occurring in flexible pavement systems. Flexural bending beam fatigue laboratory test has been used for several decades and is considered to be an integral part of the new superpave advanced characterization procedure. One of the most significant solutions to prolong the fatigue life for an asphaltic mixture is to utilize flexible materials as rubber. A laboratory testing program was performed on a conventional and Asphalt Rubber- (AR- gap-graded mixtures to investigate the impact of added rubber on the mechanical, mechanistic, and economical attributes of asphaltic mixtures. Strain controlled fatigue tests were conducted according to American Association of State Highway and Transportation Officials (AASHTO procedures. The results from the beam fatigue tests indicated that the AR-gap-graded mixtures would have much longer fatigue life compared with the reference (conventional mixtures. In addition, a mechanistic analysis using 3D-Move software coupled with a cost analysis study based on the fatigue performance on the two mixtures was performed. Overall, analysis showed that AR modified asphalt mixtures exhibited significantly lower cost of pavement per 1000 cycles of fatigue life per mile compared to conventional HMA mixture.

  4. Determination of the biodegradation rate of asphalt for the Hanford grout vaults. Hanford Grout Technology Program

    Energy Technology Data Exchange (ETDEWEB)

    Luey, J.; Li, S.W.

    1993-04-01

    Testing was initiated in March 1991 and completed in November 1992 to determine the rate at which asphalt is biodegraded by microorganisms native to the Hanford Site soils. The asphalt tested (AR-6000, US Oil, Tacoma, Washington) is to be used in the construction of a diffusion barrier for the Hanford grout vaults. Experiments to determine asphalt biodegradation rates were conducted using three separate test sets. These test sets were initiated in March 1991, January 1992, and June 1992 and ran for periods of 6 months, 11 months, and 6 months, respectively. The experimental method used was one originally developed by Bartha and Pramer (1965), and further refined by Bowerman et al. (1985), that determined the asphalt biodegradation rate through the measurement of carbon dioxide evolved.

  5. Influence of Diatomite and Mineral Powder on Thermal Oxidative Ageing Properties of Asphalt

    Directory of Open Access Journals (Sweden)

    Yongchun Cheng

    2015-01-01

    Full Text Available Ageing of asphalt affects the performances of asphalt pavement significantly. Therefore, effects of diatomite and mineral powder on ageing properties of asphalt were investigated systematically in order to improve the antiageing property of mixture. Thin film oven test (TFOT was used to conduct the short term ageing in laboratory. Softening points, penetrations, force ductility, low temperature creep properties, and viscosities of asphalt mastics were tested before and after TFOT, respectively. Results indicated that percent retained penetration (PRP increased with the increasing of fillers. Increment of softening point (ΔT, ductility retention rate (DRR, deformation energy ageing index (JAI, and viscosity ageing index (VAI of asphalt mastics nonlinearly decreased with the increasing of fillers. Ageing of asphalt was reduced by diatomite and mineral powder. And the antiageing effect of diatomite was better than that of mineral powder as a result of its porous structure. It is suggested that the mineral powder could be reasonably replaced by diatomite in order to reduce thermal oxidative ageing of asphalt mixture. The optimal content of diatomite 12.8% is also suggested for engineering.

  6. Size-dependent enrichment of waste slag aggregate fragments abraded from asphalt concrete.

    Science.gov (United States)

    Takahashi, Fumitake; Shimaoka, Takayuki; Gardner, Kevin; Kida, Akiko

    2011-10-30

    Authors consider the environmental prospects of using melted waste slag as the aggregate for asphalt pavement. In particular, the enrichment of slag-derived fragments in fine abrasion dust particles originated from slag asphalt concrete and its size dependency were concerned. A series of surface abrasion tests for asphalt concrete specimens, containing only natural aggregates as reference or 30 wt% of substituted slag aggregates, were performed. Although two of three slag-asphalt concretes generated 1.5-3.0 times larger amount of abrasion dust than the reference asphalt concrete did, it could not be explained only by abrasion resistance of slag. The enrichment of slag-derived fragments in abrasion dust, estimated on the basis of the peak intensity of quartz and heavy metal concentrations, had size dependency for all slag-asphalt concretes. Slag-derived fragments were enriched in abrasion dust particles with diameters of 150-1000 μm. Enrichment factors were 1.4-2.1. In contrast, there was no enrichment in abrasion dust particles with diameter less than 75 μm. This suggests that prior airborne-size fragmentation of substituted slag aggregates does not need to be considered for tested slag aggregates when environmental risks of abrasion dust of slag-asphalt pavement are assessed.

  7. Modification of local asphalt with epoxy resin to be used in pavement

    Directory of Open Access Journals (Sweden)

    A.M.M. Abd El Rahman

    2012-12-01

    Full Text Available The durability of asphalt pavement is greatly influenced by the environmental changes during the year. In this paper, we prepared asphalt modified by mixing asphalt 60/70 with epoxidized natural rubber (ENR in different percentages (5, 10 and 15%, which was achieved using preformed peracetic acid (aqueous solution 59% at 60–80 °C, then molten cross-linker maleic anhydride (MA was added to modified asphalt until homogenous blends are achieved. Marshall test was used to evaluate the asphalt pavement performance depending on the curing time and hardener concentration. To measure marshall test, the pervious mixture was stirred with aggregate jop formula mix (JMF and 40% MA at 150–170 °C for 20 h and 1600 rpm. From the obtained data, it was found that asphalt mixed with 15% of ENR + 40% MA achieves a high stability (16,632 Newton, air voids of 2.5%, flow of 2.9 mm and mineral voids of 14.6%. While, the stability of the unmodified asphalt was (11,500 Newton, the flow 3.2 mm, the suitable air void value was 3.7% at 5.5% with the same conditions.

  8. Sulfur extended asphalt pavement evaluation in the State of Washington: SR 270 highway pavement performance report

    Science.gov (United States)

    Mahoney, J. P.; Terrel, R. L.; Cook, J. C.

    1982-11-01

    The placement and performance of sulfur extended asphalt (SEA) paving mixtures at a highway test site (SR 270) near Pullman, Washington is summarized. The mixture and structural designs and construction details are included. This is followed by a discussion of the data collection and analysis accomplished over a three year evaluation period (1979-1982). A major experimental feature of the study was the use of 0.100 (conventional asphalt concrete), 30/70 and 40/60 SEA binder ratios (sulfur/asphalt ratios are expressed as weight percents in the experimental paving mixtures.

  9. Characteristics and applications of high-performance fiber reinforced asphalt concrete

    Science.gov (United States)

    Park, Philip

    Steel fiber reinforced asphalt concrete (SFRAC) is suggested in this research as a multifunctional high performance material that can potentially lead to a breakthrough in developing a sustainable transportation system. The innovative use of steel fibers in asphalt concrete is expected to improve mechanical performance and electrical conductivity of asphalt concrete that is used for paving 94% of U. S. roadways. In an effort to understand the fiber reinforcing mechanisms in SFRAC, the interaction between a single straight steel fiber and the surrounding asphalt matrix is investigated through single fiber pull-out tests and detailed numerical simulations. It is shown that pull-out failure modes can be classified into three types: matrix, interface, and mixed failure modes and that there is a critical shear stress, independent of temperature and loading rate, beyond which interfacial debonding will occur. The reinforcing effects of SFRAC with various fiber sizes and shapes are investigated through indirect tension tests at low temperature. Compared to unreinforced specimens, fiber reinforced specimens exhibit up to 62.5% increase in indirect tensile strength and 895% improvements in toughness. The documented improvements are the highest attributed to fiber reinforcement in asphalt concrete to date. The use of steel fibers and other conductive additives provides an opportunity to make asphalt pavement electrically conductive, which opens up the possibility for multifunctional applications. Various asphalt mixtures and mastics are tested and the results indicate that the electrical resistivity of asphaltic materials can be manipulated over a wide range by replacing a part of traditional fillers with a specific type of graphite powder. Another important achievement of this study is development and validation of a three dimensional nonlinear viscoelastic constitutive model that is capable of simulating both linear and nonlinear viscoelasticity of asphaltic materials. The

  10. Epoxy asphalt concrete paving on the deck of long-span steel bridges

    Institute of Scientific and Technical Information of China (English)

    HUANG Wei; QIAN Zhendong; CHEN Gang; YANG Jun

    2003-01-01

    It is the first systematic research in the world on the composition design of epoxy asphalt concrete as pav- ing material. Material characteristics and service perform- ance of mixture, fatigue resistance characteristics of epoxy asphalt concrete by the fatigue test of complex beam have also been described. This research indicates that epoxy asphalt concrete is a good type of paving material. Research results have been applied successfully in the paving of steel deck of the Second Nanjing Yangtze River Bridge (SNYRB). It provides a new paving type for long-span steel bridges of China and has a bright application prospect.

  11. Development of an asphalt aging procedure to assess long-term binder performance

    KAUST Repository

    Juristyarini, Pramitha

    2011-09-07

    Nine asphalts, including seven Strategic Highway Research Program asphalts and two Texas asphalts, were aged at several conditions of temperature and oxygen pressure to develop an aging test. Values for a dynamic shear rheometer function, a combination of both elastic and viscous properties that serves as an indicator of susceptibility to age-related pavement cracking, were measured for both aged and unaged samples. Each aging condition was ranked and calibrated against environmental room aging (60°C, 1 atm air), used to simulate road aging. PAV thin-film aging at 90°C, 20 atm air for 32 hr best represented environmental room aging. © Taylor & Francis Group, LLC.

  12. Building Asphalt Pavement with SBS-based Compound Added Using a Dry Process in Greenland

    DEFF Research Database (Denmark)

    Lee, Hosin; Kim, Yongjoo; Geisler, Nivi

    2009-01-01

    heavy traffic and severe weather conditions in Greenland. Based on the initial set of strain data collected under the slow-moving loader right after construction, the highest strain value was observed from the test section with the highest amount of SBS-based compound. The increased amount of SBS......-based compound seemed to affect the asphalt mix to become more flexible under the heavy loads. By adding SBS-based compound to asphalt mixtures using a “dry” process, it is expected that the pavement would become more resistant to rutting than a typical asphalt mixture used in Greenland while enduring its arctic...... weather....

  13. Recombination of asphalt with bio-asphalt : binder formulation and asphalt mixes application

    OpenAIRE

    Peralta, J.; Williams, R. Christopher; Silva, Hugo Manuel Ribeiro Dias da; Machado, A. V.

    2014-01-01

    The bio-oil from fast pyrolysis is mainly produced using organic waste materials. This is a viscoelastic material, and after a heat treatment it has a viscosity and high/intermediate thermal rheological behavior similar to many types of asphalt used in the paving industry. These two characteristics show that this material could be a good alternative to replace asphalt. In order to improve the performance of bio-oil, it was hypothesized that the addition of crumb rubber would change the rheolo...

  14. Rheological Properties of Asphalt Modified by Supramolecular UV Resistant Material-LDHs

    Institute of Scientific and Technical Information of China (English)

    WANG Jinshan; WU Shaopeng; HAN Jun; LIU Xing

    2012-01-01

    Dynamic rheological properties of asphalt modified by Supramolecular UV resistant material-layered double hydroxides(LDHs) was studied by means of the dynamic shear rheometer (DSR) test.Two typical base asphalts were chosen and modified by 2 different LDHs contents.DSR tests were performed on the original samples,samples after exposed to outdoor and samples after the artificial accelerated UV aging tests respectively to analyze the rheological properties.It is found that when the LDHs content is between 3wt% and 5wt% of asphalt weight,the high temperature performance and fatigue resistant property of the modified asphalt become better,the UV aging resistance properties are improved.

  15. Field Performance of Asphalt Pavements with New Technologies in Northern Nevada

    Science.gov (United States)

    Faeth, Benjamin Michael

    The Regional Transportation Commission (RTC) of the Washoe Valley Area has been tasked to determine if three advanced asphalt pavement technologies and one modified aggregate gradation are suitable for implementation within Reno, Stead, and Sparks Nevada. This was accomplished through research and test roads and Intersections to determine if Recycled Asphalt Pavement (RAP), Warm Mix Asphalt (WMA), Polymer-Modified Asphalt Binder, and the Type 2-R aggregate gradation were succeeding in their design plans. Over the course of several years the streets being used by RTC to test the technologies are succeeding within their design lifespans, and the Intersections being used to test the Type 2-R aggregate gradation are showing significant resistance to rutting. Due to the roads and Intersections not being more than 10 years old, these conclusions are subject to change over time.

  16. Performance of Recycled Asphalt Pavement as Coarse Aggregate in Concrete

    Directory of Open Access Journals (Sweden)

    Fidelis O. OKAFOR

    2010-12-01

    Full Text Available Recycled asphalt pavement (RAP is the reclaimed and reprocessed pavement material containing asphalt and aggregate. Most RAP is recycled back into pavements, and as a result there is a general lack of data pertaining to the mechanical properties for RAP in other possible applications such as Portland cement concrete. In the present study, some mechanical properties of Portland cement concrete containing RAP as coarse aggregate were investigated in the laboratory. Six concrete mixes of widely differing water/cement ratios and mix proportions were made using RAP as coarse aggregate. The properties tested include the physical properties of the RAP aggregate, the compressive and flexural strengths of the concrete. These properties were compared with those of similar concretes made with natural gravel aggregate. Results of the tests suggest that the strength of concrete made from RAP is dependent on the bond strength of the “asphalt-mortar” (asphalt binder-sand-filler matrix coatings on the aggregates and may not produce concrete with compressive strength above 25 MPa. However, for middle and low strength concrete, the material was found to compare favorably with natural gravel aggregate.

  17. Permanent deformation of asphalt mixes

    NARCIS (Netherlands)

    Muraya, P.M.

    2007-01-01

    This dissertation describes the results of a research that was conducted on the permanent deformation of asphalt mixtures. Central to this research was the separate characterization of the contribution of the aggregate skeleton and the bituminous mortar towards resistance to permanent deformation. T

  18. Environmental impacts of asphalt mixes with electric arc furnace steel slag.

    Science.gov (United States)

    Milačič, Radmila; Zuliani, Tea; Oblak, Tina; Mladenovič, Ana; Ančar, Janez Šč

    2011-01-01

    Electric arc furnace (EAF) steel slag can be used as an alternative high-quality material in road construction. Although asphalts with slag aggregates have been recognized as environmentally acceptable, there is a lack of data concerning the potential leaching of toxic Cr(VI) due to the highly alkaline media of EAF slag. Leaching of selected water extractable metals from slag indicated elevated concentrations of total chromium and Cr(VI). To estimate the environmental impacts of asphalt mixes with slag, leachability tests based on diffusion were performed using pure water and salt water as leaching agents. Compact and ground asphalt composites with natural aggregates, and asphalt composites in which the natural aggregates were completely replaced by slag were prepared. The concentrations of total chromium and Cr(VI) were determined in leachates over a time period of 6 mo. After 1 and 6 mo, the concentrations of some other metals were also determined in the leachates. The results indicated that chromium in leachates from asphalt composites with the addition of slag was present almost solely in its hexavalent form. However, the concentrations were very low (below 25 μg L) and did not represent an environmental burden. The leaching of other metals from asphalt composites with the addition of slag was negligible. Therefore, the investigated EAF slag can be considered as environmentally safe substitute for natural aggregates in asphalt mixes.

  19. The Potential of Heat Collection from Solar Radiation in Asphalt Solar Collectors in Malaysia

    Science.gov (United States)

    Beddu, Salmia; Talib, Siti Hidayah Abdul; Itam, Zarina

    2016-03-01

    The implementation of asphalt solar collectors as a means of an energy source is being widely studied in recent years. Asphalt pavements are exposed to daily solar radiation, and are capable of reaching up to 70°C in temperature. The potential of harvesting energy from solar pavements as an alternative energy source in replace of non-renewable energy sources prone to depletion such as fuel is promising. In Malaysia, the sun intensity is quite high and for this reason, absorbing the heat from sun radiation, and then utilizing it in many other applications such as generating electricity could definitely be impressive. Previous researches on the different methods of studying the effect of heat absorption caused by solar radiation prove to be quite old and inaffective. More recent findings, on the otherhand, prove to be more informative. This paper focuses on determining the potential of heat collection from solar radiation in asphalt solar collectors using steel piping. The asphalt solar collector model constructed for this research was prepared in the civil engineering laboratory. The hot mixed asphalt (HMA) contains 10% bitumen mixed with 90% aggregates of the total size of asphalt. Three stainless steel pipes were embedded into the interior region of the model according to the design criteria, and then put to test. Results show that harvesting energy from asphalt solar collectors proves highly potential in Malaysia due its the hot climate.

  20. Modelling and laboratory studies on the adhesion fatigue performance for thin-film asphalt and aggregate system.

    Science.gov (United States)

    Wang, Dongsheng; Yi, Junyan; Feng, Decheng

    2014-01-01

    Adhesion between asphalt and aggregate plays an important role in the performance of asphalt mixtures. A low-frequency adhesion fatigue test was proposed in this paper to study the effect of environment on the asphalt-aggregate adhesion system. The stress-based fatigue model had been utilized to describe the fatigue behavior of thin-film asphalt and aggregate system. The factors influencing the adhesion fatigue performance were also investigated. Experiment results show that asphalt has more important effect on the adhesion performance comparing with aggregate. Basalt, which is regarded as hydrophobic aggregates with low silica content, has better adhesion performance to asphalt binder when compared with granite. The effects of aging on the adhesion fatigue performance are different for PG64-22 and rubber asphalt. Long-term aging is found to reduce the adhesion fatigue lives for rubber asphalt and aggregate system, while the effect of long-term aging for aggregate and PG64-22 binder system is positive. Generally the increased stress amplitude and test temperature could induce greater damage and lead to less fatigue lives for adhesion test system.

  1. Effect of Short-Term Aging Process on the Moisture Susceptibility of Asphalt Mixtures and Binders Containing Sasobit Warm Mix Additive

    Directory of Open Access Journals (Sweden)

    Bo Li

    2015-01-01

    Full Text Available Moisture susceptibility is one of the key issues of warm mix asphalt (WMA. In this research, the moisture susceptibility of asphalt mixtures and binders containing Sasobit warm mix additive was investigated in comparison to that of hot mixture asphalt (HMA through laboratory aging experiments. The WMA asphalt mixtures were aged in the laboratory at three aging temperatures and times. The moisture susceptibility of the asphalt mixtures was measured through the laboratory immersed Marshall test and freeze-thaw splitting test. The surface free energy (SFE of asphalt binders extracted from WMA asphalt mixtures was determined by the sessile drop method. The results show that the aging time and temperature have a significant effect on the improvement in moisture susceptibility in terms of both the freeze-thaw splitting strength ratios and the residual Marshall stability of asphalt mixtures containing Sasobit warm mix additive. The SFE of asphalt binders extracted from Sasobit warm mix increased with the aging time and temperature. The moisture susceptibility of the asphalt mixtures and binders containing Sasobit warm mixes was similar to or even greater than that of HMA aging under certain conditions.

  2. The Development of Recycling Agent for Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A type of recycling agent was developed and its use for modifying used asphalt is described.The results show that the viscosity and three main properties of the aged asphalt were remarkably improved.With 5%-7% content of recycling agent, the main properties of recycled asphalt comported with China GB asphalt standard AH-70 and the recycled asphalt concrete could be used as high-grade highway.Furthermore,the recycling mechanism of the aged asphalt is discussed.

  3. Utilization of Recycled Asphalt Concrete with Warm Mix Asphalt and Cost-Benefit Analysis

    OpenAIRE

    Julide Oner; Burak Sengoz

    2015-01-01

    The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP) is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA) technology provides not only the option of recycling asphalt pavement at a lower temperature than the tempe...

  4. Compressive Strength Development and Microstrueture of Cement.asphalt Mortar

    Institute of Scientific and Technical Information of China (English)

    WANG Qiang; YAN Peiyu; KONG Xiangming; YANG Jinbo

    2011-01-01

    The compressive strength developing process and the microstructure of cement-asphalt mortar (CA mortar) were investigated.The fluidity of CA mortar has a great influence on its strength.The optimum value of spread diameter of slump flow test is in the range of 300 to 400 mm.The compressive strength of CA mortar keeps a relatively high growth rate in 56 days and grows slowly afterwards.The residual water of hydration in CA mortar freezes under minus environmental temperature which can lead to a significant reduction of the strength of CA mortar.Increasing A/C retards asphalt emulsion splitting and thus prolongs the setting process of CA mortar.The hydration products of cement form the major structural framework of hardened CA mortar and asphalt is a weak phase in the framework but improves the viscoelastic behavior of CA mortar.Therefore,asphalt emulsion should be used as much as possible on the condition that essential performance criterions of CA mortar are satisfied.

  5. A multiscale model for predicting the viscoelastic properties of asphalt concrete

    Science.gov (United States)

    Garcia Cucalon, Lorena; Rahmani, Eisa; Little, Dallas N.; Allen, David H.

    2016-08-01

    It is well known that the accurate prediction of long term performance of asphalt concrete pavement requires modeling to account for viscoelasticity within the mastic. However, accounting for viscoelasticity can be costly when the material properties are measured at the scale of asphalt concrete. This is due to the fact that the material testing protocols must be performed recursively for each mixture considered for use in the final design.

  6. Sensitivity analysis of longitudinal cracking on asphalt pavement using MEPDG in permafrost region

    OpenAIRE

    Chen Zhang; Hainian Wang; Zhanping You; Biao Ma

    2015-01-01

    Longitudinal cracking is one of the most important distresses of asphalt pavement in permafrost regions. The sensitivity analysis of design parameters for asphalt pavement can be used to study the influence of every parameter on longitudinal cracking, which can help optimizing the design of the pavement structure. In this study, 20 test sections of Qinghai–Tibet Highway were selected to conduct the sensitivity analysis of longitudinal cracking on material parameter based on Mechanistic-Empiri...

  7. 橡胶沥青防水粘结层层间抗剪性能试验分析%Test Analysis on Shear Resistance Performance between Rubber Asphalt Waterproofing Adhesive Layers

    Institute of Scientific and Technical Information of China (English)

    李正中; 宋晓燕; 肖庆一; 魏连雨

    2012-01-01

    Based on the indoor shear test stimulation of the interface bonding force status of concrete bridge deck waterproof layers, conduct systematically analysis of various factors and rules in layer shear resistance, in terms of asphalt spray amount, gravel spreading type, bridge panel interface treatment conditions and environmental temperature, etc, to propose various technical measures for improving the shear resistance performance between rubber asphalt waterproofing adhesive layers thus provide experimental basis and data support for the practical applications and construction quality. Research concludes that; in order to give full play to the shear resistance performance between rubber asphalt waterproofing adhesive layers, the shear resistance and bond performance in high temperature state must be strictly controlled, the spray volume and spray temperature should be controlled at 1. 8 ~2. 2 kg/m2 and 190 - 200 ℃ ; meanwhile, the spreading gravels should be clean with preheating treatment, the diameter ranging from 2. 36mm to 4. 75 mm; the spraying volume should be 10 kg/m2. In addition, the bridge panel surface roughness degree should be controlled within a reasonable context, when the anti-sliding value is between 45 to 55, the maximum value of interlayer shear resistance strength appears.%利用室内剪切试验模拟水泥混凝土桥面防水粘结层的界面受力状态,从沥青喷涂量、碎石撒布类型、桥面板界面处理状况、环境温度等方面系统分析影响其层间抗剪性能的各种因素及变化规律,以此提出提高橡胶沥青防水粘结层层间抗剪性能的各项技术措施,为充分发挥橡胶沥青防水粘结层的层间抗剪性能,必须严格控制其在高温状态下的抗剪和粘结性能,喷洒量和喷洒温度应控制在1.8~2.2 kg/m2和190~200℃,同时,撤布粒径为2.36~4.75mm、撒布量为10 kg/m2左右且经过预热处理的洁净碎石,而且,还应将桥面板的表面粗糙程度控

  8. 土工布在水泥混凝土路面加铺沥青混凝土层结构中的抗剪试验分析%Analysis of Shear-Bearing Test for Geotextile Between Cement Concrete and Asphalt Concrete Overlay

    Institute of Scientific and Technical Information of China (English)

    侯荣国; 牛开民; 田波

    2011-01-01

    在水泥混凝土路面加铺沥青混凝土面层(简称“白加黑”)的路面结构中,利用层间铺设土工布来延缓、减少反射裂缝是一种经常被采用的技术方案.但铺设土工布后,层间黏结力下降,容易造成沥青混凝土加铺层推移而致过早破坏.针对此现象,运用有关力学软件计算分析了水泥混凝土面板与沥青混凝土加铺层结构中的层间剪应力,发现层间光滑时的剪应力大于层间黏结时的剪应力;同时,通过试验路与室内试验,分析了铺有土工布的水泥混凝土面板与沥青混凝土层之间的抗剪能力,发现土工布满足层间抗剪要求,但抗剪富余系数不大,因此铺有土工布的水泥混凝土路面加铺沥青混凝土层的路面结构容易发生推移破坏.%To prevent reflective cracking, the geotextile is often layed between cement concrete pavement and asphalt concrete overlay. But cohesion between two layers is reduced after construction of geotextile, so it creates moving of asphalt concrete overlay. The shear stress between old cement concrete pavement and asphalt concrete overlay is analyzed through finite element model. It is found that shear stress is bigger on the assumption of perfectly smooth compared to the assumption of perfectly junction.Through experiment road and indoor test, shear-bearing capacity between cement concrete pavement and asphalt concrete overlay is analyzed while the geotextile is layed. It is found that the geotextile can satisfy the request for single shear-bearing, but redundancy coefficient is low, so moving of asphalt overlay is created easily when the geotextile is layed between old cement concrete pavement and asphalt concrete overlay.

  9. Rendering the loss of strength in dry concretes with addition of milled asphalt through microscopic analysis

    Directory of Open Access Journals (Sweden)

    T. Sachet

    Full Text Available Milled asphalt removed from old pavement carpets requires tenable handling easily reachable through its incorporation within other paving materials. This work deals with the effects of such incorporation to dry compacted concretes. Fine, intermediate, coarse and whole portions of milled asphalts were blended to a reference concrete. Mechanical tests disclosed remarkable losses on its strengths and modulus of elasticity; for the stereoscope and scanning microscopy pointed out impaired transition zones between the cement paste and the milled aggregates involved by thin asphalt films. Nevertheless, the mechanical results shown that the concretes with incorporated milled asphalt aggregates are suitable for use in pavement layers as bases and sub-bases even with reduced mechanical parameters.

  10. The addition effects of macro and nano clay on the performance of asphalt binder

    Directory of Open Access Journals (Sweden)

    M. El-Shafie

    2012-12-01

    Full Text Available The study was carried out to explore the addition effect of macro and organically modified nanoclay on the physical and mechanical properties of asphalt binders. Both macroclay and modified nanoclay were blended in an asphalt binder in various percentages (starting from 2% to 8%. The blended asphalt binders were characterized using kinematic viscosity (C.st, softening point (°C, and penetration and compared with anunmodified binder. The tensile strength of the asphalt binders was also tested as a function of clay types and content%. The results of the study indicated an increase in softening point; kinematics viscosity and decrease in binder penetration. The tensile strength of modified clay binders was enhanced at all percentages by a comparison with both macroclay and unmodified binders. The best improvements in the modified binders were obtained with 6% nanoclay.

  11. Influence of Polyethylene Glycol on Asphaltic Concrete for Cubical and Rod shaped Aggregates

    Directory of Open Access Journals (Sweden)

    U. Arun Kumar

    2014-02-01

    Full Text Available Aggregates are the principle material in pavement construction. Conventional road aggregates in India are natural aggregates obtained by crushing rocks. Aggregate characteristics such as particle size, shape, and texture etc.., influence the performance and serviceability of pavement. Pavements laid with polymer modified asphalt exhibits greater resistance to rutting, thermal cracking and fatigue damages and hence these were used at locations of higher stress. The present work concentrates on aggregate characteristics which include the shape indices. The particle shapes namely Cubical and Rod are being used in the study. The study shows the behavior of the two shapes of aggregate in terms of Penetration, Ductility, Softening Point and Marshall Stability tests with varying percentages of asphalt and also with varying the percentages of PEG. The results of unmodified asphalt mix are compared with the modified asphalt mix against some critical Marshall Mix parameters.

  12. Evaluation of steel slag coarse aggregate in hot mix asphalt concrete.

    Science.gov (United States)

    Ahmedzade, Perviz; Sengoz, Burak

    2009-06-15

    This paper presents the influences of the utilization of steel slag as a coarse aggregate on the properties of hot mix asphalt. Four different asphalt mixtures containing two types of asphalt cement (AC-5; AC-10) and coarse aggregate (limestone; steel slag) were used to prepare Marshall specimens and to determine optimum bitumen content. Mechanical characteristics of all mixtures were evaluated by Marshall stability, indirect tensile stiffness modulus, creep stiffness, and indirect tensile strength tests. The electrical sensitivity of the specimens were also investigated in accordance with ASTM D257-91. It was observed that steel slag used as a coarse aggregate improved the mechanical properties of asphalt mixtures. Moreover, volume resistivity values demonstrated that the electrical conductivity of steel slag mixtures were better than that of limestone mixtures.

  13. Performance evaluation of open-graded epoxy asphalt concrete with two nominal maximum aggregate sizes

    Institute of Scientific and Technical Information of China (English)

    罗桑; 钱振东; 薛永超

    2015-01-01

    Open-graded friction course (OGFC) is applied to pavement surfaces to increase driving safety under wet conditions, and recently, to reduce tire/pavement noise. The durability of OGFC, however, has been a concern since conventional OGFC mixes last typically less than ten years before major maintenance or rehabilitation is needed. This work investigates a new open-graded asphalt mixture that uses epoxy asphalt as binder to improve mix durability. One type of epoxy asphalt that has been successfully applied to dense-graded asphalt concrete for bridge deck paving was selected. A procedure of compacting the mix into slab specimens was developed and a series of laboratory tests were conducted to evaluate the performance of the new mix, including Cantabro loss, permeability, friction, shear strength, and wheel rutting tests. Results show superior overall performance of the open-graded epoxy asphalt mix compared to conventional open-graded asphalt mix. There are also preliminary indications that the OGFC mix with 4.75-mm NMAS gradation can improve the resistance performance to raveling, while the OGFC mix with 9.5-mm NMAS gradation can improve the performance of surface friction at a high slip speed.

  14. Normalization method for asphalt mixture fatigue equation under different loading frequencies

    Institute of Scientific and Technical Information of China (English)

    吕松涛; 郑健龙

    2015-01-01

    In order to analyze the effect of different loading frequencies on the fatigue performance for asphalt mixture, the changing law of asphalt mixture strengths with loading speed was revealed by strength tests under different loading speeds. Fatigue equations of asphalt mixtures based on the nominal stress ratio and real stress ratio were established using fatigue tests under different loading frequencies. It was revealed that the strength of the asphalt mixture is affected by the loading speed greatly. It was also discovered that the fatigue equation based on the nominal stress ratio will change with the change of the fatigue loading speed. There is no uniqueness. But the fatigue equation based on the real stress ratio doesn’t change with the loading frequency. It has the uniqueness. The results indicate the fatigue equation based on the real stress ratio can realize the normalization of the asphalt mixture fatigue equation under different loading frequencies. It can greatly benefit the analysis of the fatigue characteristics under different vehicle speeds for asphalt pavement.

  15. A study on engineering characteristics of asphalt concrete using filler with recycled waste lime.

    Science.gov (United States)

    Sung Do, Hwang; Hee Mun, Park; Suk keun, Rhee

    2008-01-01

    This study focuses on determining the engineering characteristics of asphalt concrete using mineral fillers with recycled waste lime, which is a by-product of the production of soda ash (Na(2)CO(3)). The materials tested in this study were made using a 25%, 50%, 75%, and 100% mixing ratio based on the conventional mineral filler ratio to analyze the possibility of using recycled waste lime. The asphalt concretes, made of recycled waste lime, hydrated lime, and conventional asphalt concrete, were evaluated through their fundamental engineering properties such as Marshall stability, indirect tensile strength, resilient modulus, permanent deformation characteristics, moisture susceptibility, and fatigue resistance. The results indicate that the application of recycled waste lime as mineral filler improves the permanent deformation characteristics, stiffness and fatigue endurance of asphalt concrete at the wide range of temperatures. It was also determined that the mixtures with recycled waste lime showed higher resistance against stripping than conventional asphalt concrete. It was concluded from various test results that a waste lime can be used as mineral filler and, especially, can greatly improve the resistance of asphalt concrete to permanent deformation at high temperatures.

  16. Performance evaluation of open-graded epoxy asphalt concrete with two nominal maximum aggregate sizes

    Institute of Scientific and Technical Information of China (English)

    罗桑; 钱振东; 薛永超

    2015-01-01

    Open-graded friction course(OGFC) is applied to pavement surfaces to increase driving safety under wet conditions, and recently, to reduce tire/pavement noise. The durability of OGFC, however, has been a concern since conventional OGFC mixes last typically less than ten years before major maintenance or rehabilitation is needed. This work investigates a new open-graded asphalt mixture that uses epoxy asphalt as binder to improve mix durability. One type of epoxy asphalt that has been successfully applied to dense-graded asphalt concrete for bridge deck paving was selected. A procedure of compacting the mix into slab specimens was developed and a series of laboratory tests were conducted to evaluate the performance of the new mix, including Cantabro loss, permeability, friction, shear strength, and wheel rutting tests. Results show superior overall performance of the open-graded epoxy asphalt mix compared to conventional open-graded asphalt mix. There are also preliminary indications that the OGFC mix with 4.75-mm NMAS gradation can improve the resistance performance to raveling, while the OGFC mix with 9.5-mm NMAS gradation can improve the performance of surface friction at a high slip speed.

  17. 泡沫沥青温拌沥青混合料配合比设计方法及路用性能研究%Study on Design Method and Road Performance of Foam Asphalt Warm Asphalt Mixture

    Institute of Scientific and Technical Information of China (English)

    熊家元

    2016-01-01

    foam asphalt warm mix asphalt mixture is a new material,new energy efficient and envi-ronmentally friendly pavement engineering .draw lessons fromsubstantial warm foam asphalt technolo-gyproject,this article Carry on warm mix asphalt foam mix design method,while the warm mix asphalt foam road performance with the same type of hot mix asphalt were compared.Test results show that:rec-ommend to“4% void method”to determine the mixing temperature of foam warm asphalt mixture,Mar-shall method of foam temperature on the optimum proportion of asphalt mixture,The road performance verification,foam warm mix asphalt mixture has better high temperature stability,but its water stability and low temperature crack resistance is poor,the fatigue performance foam warm mix asphalt mixture is 90% of the same type asphalt mixture.Comprehensive road performance of both foam asphalt warm as-phalt mixture and hot mix asphalt are relatively close.%泡沫沥青温拌沥青混合料是一种全新的节能环保型路面新材料,借鉴实体工程采用的温拌泡沫沥青技术,开展温拌泡沫沥青混合料配合比设计方法研究,同时将温拌泡沫沥青混合料的路用性能与同类型热拌沥青混合料进行了对比。试验结果表明:推荐采用“4%空隙率法”确定泡沫沥青温拌混合料的拌合温度,以马歇尔法确定泡沫温拌沥青混合料的最佳油石比,经路用性能验证,泡沫温拌沥青混合料具有较好的高温稳定性,但其水稳定性和低温抗裂性稍差,泡沫温拌沥青混合料疲劳性能为同类型沥青混合料的90%,泡沫温拌和热拌沥青混合料的综合路用性能比较接近。

  18. Pelletized Asphalt for Airfield Damage Repair

    Science.gov (United States)

    2009-08-01

    14, 2008. Gulf Asphalt Contractor (GAC), Panama City, FL, provided all labor , material (with the exception of pelletized asphalt) and equipment for...produced. Benefits include: reduced transportation, traffic disruption, operating costs, and labor costs, while increased productivity and... Mercado , E. A., A. Epps Martin, E. S. Park, C. Spiegelman, and C. J. Glover, “Factors Affecting Binder Properties between Production and Construction

  19. Hot Mix Asphalt Recycling: Practices and Principles

    NARCIS (Netherlands)

    Mohajeri, M.

    2015-01-01

    Hot mix asphalt recycling has become common practice all over the world since the 1970s because of the crisis in oil prices. In the Netherlands, hot recycling has advanced to such an extent that in most of the mixtures more than 50% of reclaimed asphalt (RA) is allowed. These mixtures with such a hi

  20. Asphalt Raking. Instructor Manual. Trainee Manual.

    Science.gov (United States)

    Laborers-AGC Education and Training Fund, Pomfret Center, CT.

    This packet consists of the instructor and trainee manuals for an asphalt raking course. The instructor manual contains a course schedule for 4 days of instruction, content outline, and instructor outline. The trainee manual is divided into five sections: safety, asphalt basics, placing methods, repair and patching, and clean-up and maintenance.…

  1. Viscoelastoplastic constitutive model for creep deformation behavior of asphalt sand

    Institute of Scientific and Technical Information of China (English)

    叶永; 杨新华; 陈传尧

    2008-01-01

    A uniaxial viscoelastoplastic model that can describe whole creep behaviors of asphalt sand at different temperatures was presented.The model was composed of three submodels in series,which describe elastoplastic,viscoelastic and viscoplastic characteristics respectively.The constitutive equation was established for uniaxial loading condition,and the creep representation was also obtained.The constitutive parameters were determined by uniaxial compression tests under controlled-stress of 0.1 MPa with five different test temperatures of 20,40,45,50 and 60 ℃.Expressions of the model parameters in terms of temperatures were also given.The model gave prediction at various temperatures consistent with the experimental results,and can reflect the total deformation characterization of asphalt sands.

  2. Evaluation of the relationship between PAH content and mutagenic activity of fumes from roofing and paving asphalts and coal tar pitch.

    Science.gov (United States)

    Machado, M L; Beatty, P W; Fetzer, J C; Glickman, A H; McGinnis, E L

    1993-11-01

    Fume condensates from asphalt and coal tar pitch were evaluated to determine if polycyclic aromatic hydrocarbon (PAH) composition, crude oil source, or temperature at which the fume was generated correlated with mutagenic activity. The fume condensates were tested for mutagenic activity using a modified Ames Test. Benzo[a]pyrene (BP) and other PAHs were detected in all samples. The concentration of BP in coal tar pitch was 18,100 ppm while the concentration in asphalt was less than 6 ppm. Coal tar fumes contained between two and three orders of magnitude more BP, as well as other PAH species, than asphalt fumes. Coal tar fume condensates were also approximately 100 times more mutagenic than those of asphalt. Generation temperature, crude oil source, and/or process conditions affected the PAH concentrations but not the mutagenicity in roofing asphalt fume condensates. With paving asphalt fumes, PAH content and mutagenicity varied with crude oil source but not with processing conditions; due to limited data, it was not possible to determine the effect of generation temperature. Coal tar pitch fumes generated at 316 degrees C contained significantly higher concentrations of PAHs than those generated at 232 degrees C and the mutagenic activity generally paralleled the PAH content. A subset of the paving asphalts demonstrated good correlation between mutagenicity and three- to seven-ring PAH content. These results indicate that asphalt fumes are far less mutagenic than coal tar fumes. Asphalt fumes differ in their ability to induce mutagenic activity, and, most likely, in their potential carcinogenicity.

  3. Effect of Zn/Al Layered Double Hydroxide Containing 2-Hydroxy-4-n-octoxy-benzophenone on UV Aging Resistance of Asphalt

    Directory of Open Access Journals (Sweden)

    Chao Peng

    2015-01-01

    Full Text Available UV radiation is a main factor to reduce the service life of asphalt pavement due to the UV aging of asphalt binder. To obtain enhanced UV aging resistance, an organic UV absorber called 2-hydroxy-4-n-octoxy-benzophenone (HNOB had been intercalated into an inorganic UV absorber called Zn/Al layered double hydroxide (LDH to play a combined anti-UV role in asphalt binder. Fourier transform infrared spectroscopy revealed that HNOB anions have been intercalated into the interlayer galleries of Zn/Al-LDH containing HNOB anions (Zn/Al-HNOB−-LDH. X-ray diffraction results of Zn/Al-LDH containing CO32− anions (Zn/Al-CO32--LDH and Zn/Al-CO32--LDH/styrene-butadiene-styrene (SBS modified asphalt disclosed that asphalt molecules entered into LDH interlayer galleries to form an expanded phase structure. UV-Vis absorbance patterns showed that Zn/Al-HNOB−-LDH has a better capacity of blocking UV light due to the synergetic effect of HNOB and Zn/Al-LDH. The chemical fractions analysis, conventional physical tests, and rheological tests of SBS modified asphalt, Zn/Al-CO32--LDH/SBS modified asphalt, and Zn/Al-HNOB−-LDH/SBS modified asphalt before and after UV aging testified that Zn/Al-HNOB−-LDH can improve the UV aging resistance of SBS modified asphalt more significantly.

  4. Property Analysis of Exfoliated Graphite Nanoplatelets Modified Asphalt Model Using Molecular Dynamics (MD Method

    Directory of Open Access Journals (Sweden)

    Hui Yao

    2017-01-01

    Full Text Available This Molecular Dynamics (MD simulation paper presents a physical property comparison study between exfoliated graphite nanoplatelets (xGNP modified and control asphalt models, including density, glass transition temperature, viscosity and thermal conductivity. The three-component control asphalt model consists of asphaltenes, aromatics, and saturates based on previous references. The xGNP asphalt model was built by incorporating an xGNP and control asphalt model and controlling mass ratios to represent the laboratory prepared samples. The Amber Cornell Extension Force Field (ACEFF was used with assigned molecular electro-static potential (ESP charge from NWChem analysis. After optimization and ensemble relaxation, the properties of the control and xGNP modified asphalt models were computed and analyzed using the MD method. The MD simulated results have a similar trend as the test results. The property analysis showed that: (1 the density of the xGNP modified model is higher than that of the control model; (2 the glass transition temperature of the xGNP modified model is closer to the laboratory data of the Strategic Highway Research Program (SHRP asphalt binders than that of the control model; (3 the viscosities of the xGNP modified model at different temperatures are higher than those of the control model, and it coincides with the trend in the laboratory data; (4 the thermal conductivities of the xGNP modified asphalt model are higher than those of the control asphalt model at different temperatures, and it is consistent with the trend in the laboratory data.

  5. Investigation of γ-(2,3-Epoxypropoxypropyltrimethoxy Silane Surface Modified Layered Double Hydroxides Improving UV Ageing Resistance of Asphalt

    Directory of Open Access Journals (Sweden)

    Canlin Zhang

    2017-01-01

    Full Text Available γ-(2,3-Epoxypropoxypropyltrimethoxy silane surface modified layered double hydroxides (KH560-LDHs were prepared and used to improve the ultraviolet ageing resistance of asphalt. The results of X-ray photoelectron spectrometry (XPS indicated that KH560 has been successfully grafted onto the surface of LDHs. The agglomeration of LDHs particles notably reduced after KH560 surface modification according to scanning electron microscopy (SEM, which implied that the KH560 surface modification was helpful to promote the dispersibility of LDHs in asphalt. Then, the influence of KH560-LDHs and LDHs on the physical and rheological properties of asphalt before and after UV ageing was thoroughly investigated. The storage stability test showed that the difference in softening point (ΔS of LDHs modified asphalt decreased from 0.6 °C to 0.2 °C at an LDHs content of 1% after KH560 surface modification, and the tendency became more pronounced with the increase of LDH content, indicating that KH560 surface modification could improve the stability of LDHs in asphalt. After UV ageing, the viscous modulus (G’’ of asphalt significantly reduced, and correspondingly, the elastic modulus (G’ and rutting factor (G*/sin δ rapidly increased. Moreover, the asphaltene increased and the amount of “bee-like” structures of the asphalt decreased. Compared with LDHs, KH560-LDHs obviously restrained performance deterioration of the asphalt, and helped to relieve the variation of the chemical compositions and morphology of asphalt, which suggested that the improvement of KH560-LDHs on UV ageing resistance of asphalt was superior to LDHs.

  6. A hybrid strategy in selecting diverse combinations of innovative sustainable materials for asphalt pavements

    Directory of Open Access Journals (Sweden)

    Baron Colbert

    2016-04-01

    Full Text Available This project integrates recent innovations of recycled materials used in designing and building sustainable pavements. An increasing environmental awareness and the demand for improving economic and construction efficiencies, through measures such as construction warrantees and goals to reduce air pollution under the Kyoto Protocol, have increased the efforts to implement sustainable materials in roadways. The objective of this research is to develop a systematic approach toward selecting optimum combinations of sustainable materials for the construction of asphalt pavements. The selected materials, warm mix asphalt (WMA, recycled asphalt shingles (RAS, and reclaimed asphalt pavement (RAP were incorporated in this study. The results of this research are intended to serve as guidelines in the selection of the mixed sustainable materials for asphalt pavements. The approach developed from this project draws upon previous research efforts integrating graphical modeling with optimizing the amount of sustainable materials based on the performance. With regard to moisture susceptibility and rutting potential test results, as well as the MIM analysis based on a 95% confidence interval, the rutting performance and moisture susceptibility of asphalt mixtures are not significantly different regardless of the percentages of RAS, RAP, or WMA. The optimum mixture choices could be made by the plant emission rankings with consideration of the optimal WMA types, percentages of RAS/RAP, and WMA production temperatures. The WMA mixtures prepared with 75% RAP and Advera® WMA have produced the lowest CO2 emissions among the investigated mixture types.

  7. USE OF RECLAIMED ASPHALT PAVEMENT WITH MILLED ROAD PAVEMENT LAYERS

    Directory of Open Access Journals (Sweden)

    Andrzej Plewa

    2015-07-01

    Full Text Available The article presents the results of research on the functional properties of asphalt mixes using RAP obtained from milling asphalt road pavements. Asphalt concrete AC 22P with 0%, 10%, 15% and 20% addition of RAP used for base course of road pavements were designed. It was found that asphalt mixes with RAP characterized by comparable and in some cases better functional properties compared to the asphalt mixes without RAP (0%. One should notice the influence of RAP on the performance and durability of the asphalt mixtures, as compared to virgin asphalt mixtures (without RAP.

  8. Test method and index of the influence of anti-stripping agents on water stability of asphalt mixture%抗剥落剂对沥青混合料水稳定性影响的试验方法与指标研究

    Institute of Scientific and Technical Information of China (English)

    张苛; 张争奇

    2015-01-01

    In order to evaluate the influence of anti-stripping agents on water stability of asphalt mix-ture in salty and humid environment reasonably ,anti-stripping agent PA-1(P) ,AMR(A) and TJ-066 (T) were selected ,and the optimum mixing amount of anti-stripping agents were determined by adhe-sion test of asphalt and aggregate .The Hamburg wheel tracking test in water at different tempera-tures on asphalt mixtures mixed with anti-stripping agents was carried out ,and the test condition and evaluation index were also discussed .The results show that the optimum mixing amount of anti-strip-ping agent P ,A or T in salty and humid environment are slightly larger than in conventional environ-ment ,the optimum mixing amount of anti-stripping agent P ,A and T are 0.4% ,0.5% and 0.5% of asphalt content respectively .The Hamburg wheel tracking test in water at 50 ℃ is a good way to e-valuate the influence of different anti-stripping agents on water stability of asphalt mixture .The index of rutting depth rate is put forward in view of the deficiency of the evaluation index of the Hamburg wheel tracking test in water .The rutting depth rate of asphalt mixture mixed with anti-stripping a-gent A is the smallest ,and stripping number is the biggest .Anti-stripping agent A is recommended to improve the water stability of asphalt mixture in salty and humid area .%为了合理地评价抗剥落剂对含盐高湿环境下沥青混合料水稳定性的影响,文章以抗剥落剂 PA-1、A M R和T J-066为研究对象,通过沥青与集料的黏附性试验确定抗剥落剂的最佳掺量,在不同温度下对掺有抗剥落剂的沥青混合料进行浸水汉堡车辙试验,并讨论了浸水汉堡车辙试验的试验条件和评价指标。结果表明:在含盐高湿环境中抗剥落剂 P、A、T 的最佳掺量略大于淡水环境,分别为沥青用量的0.4%、0.5%和0.5%;采用50℃时浸水汉堡车辙试验可以很好地评价不同抗剥落剂对沥青

  9. Thermal behavior of crumb-rubber modified asphalt concrete mixtures

    Science.gov (United States)

    Epps, Amy Louise

    Thermal cracking is one of the primary forms of distress in asphalt concrete pavements, resulting from either a single drop in temperature to an extreme low or from multiple temperature cycles above the fracture temperature of the asphalt-aggregate mixture. The first mode described is low temperature cracking; the second is thermal fatigue. The addition of crumb-rubber, manufactured from scrap tires, to the binder in asphalt concrete pavements has been suggested to minimize both types of thermal cracking. Four experiments were designed and completed to evaluate the thermal behavior of crumb-rubber modified (CRM) asphalt-aggregate mixtures. Modified and unmodified mixture response to thermal stresses was measured in four laboratory tests. The Thermal Stress Restrained Specimen Test (TSRST) and the Indirect Tensile Test (IDT) were used to compare mixture resistance to low temperature cracking. Modified mixtures showed improved performance, and cooling rate did not affect mixture resistance according to the statistical analysis. Therefore results from tests with faster rates can predict performance under slower field rates. In comparison, predicted fracture temperatures and stresses (IDT) were generally higher than measured values (TSRST). In addition, predicted fracture temperatures from binder test results demonstrated that binder testing alone is not sufficient to evaluate CRM mixtures. Thermal fatigue was explored in the third experiment using conventional load-induced fatigue tests with conditions selected to simulate daily temperature fluctuations. Test results indicated that thermal fatigue may contribute to transverse cracking in asphalt pavements. Both unmodified and modified mixtures had a finite capacity to withstand daily temperature fluctuations coupled with cold temperatures. Modified mixtures again exhibited improved performance. The fourth experiment examined fracture properties of modified and unmodified mixtures using a common fracture toughness test

  10. Assessment of dynamic modulus of high density polypropylene waste fiber reinforcement in asphalt concrete

    Directory of Open Access Journals (Sweden)

    Hassan S. OTUOZE

    2015-12-01

    Full Text Available Traditional asphalt tests like Hveem and Marshall tests are at best mere characterization than effective test of pavement field performance because of complex viscoelastic behavior of asphalt. Mechanical properties otherwise called simple performance tests (SPT are performance criteria of asphalt. Dynamic modulus among other SPT’s like permanent deformation, fatigue cracking, thermal cracking, moisture susceptibility, shear and friction properties; determines stress-strain to time-temperature relationships that imparts on strength, service life and durability. The test followed the recommendations of NCHRP 1-37a (2004 and mixes were prepared using 0, 0.5, 1.0 and 1.5% HDPP contents. The parameters tested for dynamic modulus, /E*/, are stiffness, recoverable strain (ε, and phase angle (ξ. Time – temperature superposition (TTS called master curve was fitted using sigmoidal curve to interpolate the parameters beyond measured data set so as to observe the viscoelastic behavior outside the physical properties. The performance of 0.5% HDPP asphalt is better enhanced than the conventional asphalt to improve upon strength, service and durability.

  11. USE OF RECLAIMED ASPHALT PAVEMENT WITH MILLED ROAD PAVEMENT LAYERS

    OpenAIRE

    Andrzej Plewa; Marta Wasilewska; Władysław Gardziejczyk; Paweł Gierasimiuk

    2015-01-01

    The article presents the results of research on the functional properties of asphalt mixes using RAP obtained from milling asphalt road pavements. Asphalt concrete AC 22P with 0%, 10%, 15% and 20% addition of RAP used for base course of road pavements were designed. It was found that asphalt mixes with RAP characterized by comparable and in some cases better functional properties compared to the asphalt mixes without RAP (0%). One should notice the influence of RAP on the performance and ...

  12. Effects of Nominal Maximum Aggregate Size on the Performance of Stone Matrix Asphalt

    Directory of Open Access Journals (Sweden)

    Hongying Liu

    2017-01-01

    Full Text Available It is well known that the performance of hot mix asphalt (HMA in service life is closely related to a proper aggregate gradation. A laboratory study was conducted to investigate the effects of nominal maximum aggregate size (NMAS on the performance of stone matrix asphalt (SMA. The volumetric characteristics and performance properties obtained from wheel tracking tests, permeability test, beam bending test, contabro test are compared for SMA mixes with different NMAS. The results indicated that voids in mineral aggregate (VMA and voids filled with asphalt (VFA of SMA mixtures increased with a decrease of aggregate size in aggregate gradation. SMA30 had the lowest optimum asphalt content among all the mixtures. Increase of NMAS contributed to improvement of the rutting resistance of SMA mixtures. However, a decrease of NMAS showed better cracking and raveling resistance. Permeability rate of SMA was primarily affected by the air voids (AV and break point sieve, but was also sensitive to aggregate gradation to some extent, with reduced NMAS corresponding to less permeability rate. Based on the test results, SMA5 and SMA13 are suggested to be used as a water-proof layer in bridge deck pavement, and SMA20 and SMA30 are suggested to be used as binder course in asphalt pavement, which needs to possess superior rutting resistance at high temperature.

  13. Asphalt fume dermal carcinogenicity potential: I. dermal carcinogenicity evaluation of asphalt (bitumen) fume condensates.

    Science.gov (United States)

    Clark, Charles R; Burnett, Donald M; Parker, Craig M; Arp, Earl W; Swanson, Mark S; Minsavage, Gary D; Kriech, Anthony J; Osborn, Linda V; Freeman, James J; Barter, Robert A; Newton, Paul E; Beazley, Shelley L; Stewart, Christopher W

    2011-10-01

    Asphalt (bitumen) fume condensates collected from the headspace above paving and Type III built up roofing asphalt (BURA) tanks were evaluated in two-year dermal carcinogenicity assays in male C3H/HeNCrl mice. A third sample was generated from the BURA using a NIOSH laboratory generation method. Similar to earlier NIOSH studies, the BURA fume condensates were applied dermally in mineral oil twice per week; the paving sample was applied 7 days/week for a total weekly dose of 50 mg/wk in both studies. A single benign papilloma was observed in a group of 80 mice exposed to paving fume condensate at the end of the two-year study and only mild skin irritation was observed. The lab generated BURA fume condensate resulted in statistically significant (P<0.0001) increases in squamous cell carcinomas (35 animals or 55% of animals at risk). The field-matched BURA condensate showed a weaker but significant (P=0.0063) increase (8 carcinomas or 13% of animals) and a longer average latency (90 weeks vs. 76 for the lab fume). Significant irritation was observed in both BURA condensates. It is concluded that the paving fume condensate was not carcinogenic under the test conditions and that the field-matched BURA fume condensate produced a weak tumor response compared to the lab generated sample.

  14. Investigation of thermal properties of raw materials of asphalt mixtures

    Science.gov (United States)

    Géber, R.; Simon, A.; Kocserha, I.

    2017-02-01

    Asphalt mixtures are composite materials, which are made of different grades of mineral aggregates and bitumen. During the mixing process mineral materials were blended with bitumen at relatively high temperature (∼200 °C). As the binding process come off in these higher temperature range, thermal properties of asphaltic materials are important. The aim of this project is to reveal the thermal properties of raw materials. During our research two types of mineral aggregates were tested (limestone and dolomite) by different methods. Differential thermal analysis, thermal expansion and thermal conductivity were investigated at technologically important temperatures. The results showed that the structure of mineral materials did not change at elevated temperatures, expansion of samples was neglible, while thermal conductivity changed by temperature.

  15. 天然岩沥青对沥青路用性能的影响研究%Research on Influences of Natural Rock Asphalt on Road Performances of Asphalt

    Institute of Scientific and Technical Information of China (English)

    林晓光; 金年生; 林立; 杨真子

    2015-01-01

    采用布敦岩沥青及国产青川岩沥青分别对基质沥青进行改性,应用动态剪切流变试验、低温弯曲梁流变试验及旋转薄膜老化试验,全面研究岩沥青类型及掺量对沥青的高温流变性能、低温流变性能和抗老化性等路用性能的影响。试验结果表明:岩沥青的掺加对基质沥青的路用性能具有良好的改善作用;对于不同类型岩沥青,沥青的高温流变性能均随着岩沥青掺量的不断增大而不断改善,低温流变性能则略有降低,抗老化性能不断增强;在相同岩沥青掺量条件下,国产青川岩沥青对沥青的高温性能、低温性能及抗老化性能等路用性能的改善效果均优于布敦岩沥青。%This paper modifies matrix asphalt by means of Buton Rock Asphalt and domestic Qingchuan natural rock asphalt,respectively,and thoroughly searches the influences of types and proportions of rock asphalt on road performances such as high -temperature rheological property, low -temperature rheological property and aging resistance,etc.by means of dynamic shear rheometer test,low -temperature bending beam rheological test and rotating thin film aging test.The test results show that mixture of rock asphalt can well improve road performance of matrix asphalt;for different types of rock asphalt,the high -temperature rheological property of asphalt is continuously improved with continuous increase of proportion of rock asphalt,while the low -temperature rheological property slightly decrease, and the aging resistance enhances continuously;under the condition of the same proportion of rock asphalt,domestic Qingchuan rock asphalt exhibits effect of improvement for road performance including high -temperature property,low -temperature property and aging resistance,etc.superior to Buton Rock Asphalt.

  16. Representative volume element of asphalt pavement for electromagnetic measurements

    Directory of Open Access Journals (Sweden)

    Terhi Pellinen

    2015-02-01

    Full Text Available The motivation for this study was to investigate the representative volume element (RVE needed to correlate the nondestructive electromagnetic (EM measurements with the conventional destructive asphalt pavement quality control measurements. A large pavement rehabilitation contract was used as the test site for the experiment. Pavement cores were drilled from the same locations where the stationary and continuous Ground Penetrating Radar (GPR measurements were obtained. Laboratory measurements included testing the bulk density of cores using two methods, the surface-saturated dry method and determining bulk density by dimensions. Also, Vector Network Analyzer (VNA and the through specimen transmission configuration were employed at microwave frequencies to measure the reference dielectric constant of cores using two different footprint areas and therefore volume elements. The RVE for EM measurements turns out to be frequency dependent; therefore in addition to being dependent on asphalt mixture type and method of obtaining bulk density, it is dependent on the resolution of the EM method used. Then, although the average bulk property results agreed with theoretical formulations of higher core air void content giving a lower dielectric constant, for the individual cores there was no correlation for the VNA measurements because the volume element seizes deviated. Similarly, GPR technique was unable to capture the spatial variation of pavement air voids measured from the 150-mm drill cores. More research is needed to determine the usable RVE for asphalt.

  17. TOR橡胶沥青流变性能试验%Experiments on rheological properties of TOR asphalt rubber

    Institute of Scientific and Technical Information of China (English)

    肖鹏; 吴美平; 周鑫

    2012-01-01

    为了得到TOR橡胶沥青的流变性能,对薄膜烘箱老化和压力老化试验后的沥青试样进行布氏黏度试验和动态剪切流变试验.给出了改性沥青的制备方法、试验方法,分析了TOR对橡胶沥青复数模量、相位角、车辙因子、黏度、疲劳因子的影响.结果表明:加入TOR后,沥青的复数模量增大,相位角减小,TOR促进了废胶粉颗粒与沥青的相容性,增加了沥青的高温抗车辙性能.薄膜加热老化后基质沥青、橡胶沥青和TOR橡胶沥青的车辙因子数值均增大,黏温敏感性增强,TOR橡胶沥青的抗车辙性能较橡胶沥青有所改善.加入TOR的橡胶沥青,经压力老化后抗疲劳性能得到了加强,在较低温度环境下比橡胶沥青好;经有水压力老化,可以有效改善橡胶沥青的热氧水老化能力.%In order to investigate rheological properties of TOR rubber asphalt, asphalts were determined by Brinell viscosity and dynamic shear rheometer (DSR) after film oven and pressure aging treatments. The preparation and test method of modified asphalt were proposed, and the influences of TOR on the asphalt rubber properties of complex modulus, phase angle, rut factor, viscosity and fatigue factor were analysed. The results show that the complex modulus is increased by adding TOR, but with decreased phase angle. TOR can promote the compatibility between waster rubber powder particles and asphalt with increased rutting resistance at high temperature. The rut factors of asphalt, asphalt rubber and TOR asphalt rubber are all increased after heat aging with increased viscosity-temperature sensitivity. Compared with asphalt rubber, TOR asphalt rubber has better rutting resistance in actual process. The fatigue resistance of TOR asphalt rubber is improved and better than that of asphalt rubber at low temperature after pressure aging. The resistance abilities of TOR asphalt rubber to heat, oxygen and water are effectively improved after pressure aging

  18. The Effects of Salt on Rheological Properties of Asphalt after Long-Term Aging

    Directory of Open Access Journals (Sweden)

    Xin Yu

    2013-01-01

    Full Text Available Limited studies in recent years have shown that asphalt pavement subject to seawater in coastal regions or deicing salt in cold regions may be seriously damaged after being soaked in saline water for a long time. However, there is limited research into the influence of salt on rheological properties of asphalt after long-term aging. In this study, rheological properties of unmodified and polymer-modified asphalt after long-term aging were tested after being soaked in different concentrations of salt (0.3%~5% for different durations (1 day~30 days. Orthogonal array based on the Taguchi method was used for experimental design. The frequency sweep tests were performed on the specimens of aged asphalt after being soaked for complex modulus and phase angle master curves and ultimate fatigue temperature. BBR tests were performed for stiffness. The test results indicate that saline water appears to reduce low temperature properties and fatigue resistance properties and improved high temperature properties of aged asphalt, and it also affects the sensitivity of complex modulus and phase angles at low frequencies.

  19. The effects of salt on rheological properties of asphalt after long-term aging.

    Science.gov (United States)

    Yu, Xin; Wang, Ying; Luo, Yilin; Yin, Long

    2013-01-01

    Limited studies in recent years have shown that asphalt pavement subject to seawater in coastal regions or deicing salt in cold regions may be seriously damaged after being soaked in saline water for a long time. However, there is limited research into the influence of salt on rheological properties of asphalt after long-term aging. In this study, rheological properties of unmodified and polymer-modified asphalt after long-term aging were tested after being soaked in different concentrations of salt (0.3%~5%) for different durations (1 day~30 days). Orthogonal array based on the Taguchi method was used for experimental design. The frequency sweep tests were performed on the specimens of aged asphalt after being soaked for complex modulus and phase angle master curves and ultimate fatigue temperature. BBR tests were performed for stiffness. The test results indicate that saline water appears to reduce low temperature properties and fatigue resistance properties and improved high temperature properties of aged asphalt, and it also affects the sensitivity of complex modulus and phase angles at low frequencies.

  20. Three-dimensional modeling and simulation of asphalt concrete mixtures based on X-ray CT microstructure images

    Directory of Open Access Journals (Sweden)

    Hainian Wang

    2014-02-01

    Full Text Available X-ray CT (computed tomography was used to scan asphalt mixture specimen to obtain high resolution continuous cross-section images and the meso-structure. According to the theory of three-dimensional (3D reconstruction, the 3D reconstruction algorithm was investigated in this paper. The key to the reconstruction technique is the acquisition of the voxel positions and the relationship between the pixel element and node. Three-dimensional numerical model of asphalt mixture specimen was created by a self-developed program. A splitting test was conducted to predict the stress distributions of the asphalt mixture and verify the rationality of the 3D model.

  1. Effects of asphalt rejuvenator on thermal and mechanical properties on oxidized hot mixed asphalt pavements

    Science.gov (United States)

    Farace, Nicholas A.; Buttlar, William G.; Reis, Henrique

    2016-04-01

    The utilization of asphalt rejuvenator, and its effectiveness for restoring thermal and mechanical properties was investigated via Disk-shaped Compact Tension (DC(T)) and acoustic emission (AE) testing for determining mechanical properties and embrittlement temperatures of the mixtures. During the DC(T) testing the fracture energies and peak loads were used to measure the resistance of the rejuvenated asphalt to low temperature cracking. The AE testing monitored the acoustic emission activity while the specimens were cooled from room temperature to -40 °C to estimate the temperature at which thermal cracking began (i.e. the embrittlement temperature). First, a baseline response was obtained by obtaining the mechanical and thermal response of virgin HMA samples and HMA samples that had been exposed to oxidative aging for 36 hours at 135°C. The results showed the virgin samples had much higher peak loads and fracture energies than the 36 hours aged samples. Acoustic Emission showed similar results with the virgin samples having embrittlement temperatures 10 °C cooler than the 36 hours aged specimens. Then, overaged for 36 hours specimens were treated different amounts of rejuvenator (10%, 15%, and 20% by weight of binder content) and left to dwell for increased amount of time periods varying from one to eight weeks. It was observed that the AE results showed an improvement of embrittlement temperature with increasing with the dwell times. The 8 weeks specimens had cooler embrittlement temperatures than the virgin specimens. Finally, the low temperature effects on fracture energy and peak load of the rejuvenated asphalt was investigated. Rejuvenator was applied (10% by weight of binder) to specimens aged 36 hours at 135 °C, and the dwell time was varied from 1 to 4 weeks. The results showed that the peak loads were restored to levels of the virgin specimens, and the fracture energies improved to levels beyond that of the virgin specimens. The results also showed a

  2. Road Performance of Drainage Asphalt Pavement%排水沥青路面的路用性能

    Institute of Scientific and Technical Information of China (English)

    连艳霞

    2014-01-01

    Drainage asphalt pavement has features such as drainage, anti-slip and noise reduction. It can greatly improve driving safety and reduce the incidence of traffic accidents. In order to study its road per-formance, contrast tests on road performance of mixtures with different types of gradation, different as-phalt as well as same gradation types, different asphalt are conducted. The result shows that polymer modi-fied asphalt has better high temperature performance and dynamic viscosity than asphalt A and drainage asphalt pavement has excellent road performance than OGFC asphalt mixture.%排水沥青路面具有排水、防滑和降噪等功能,可提高行车安全性,降低交通事故率。为研究其路用性能,通过进行不同级配类型、不同沥青和相同级配类型、不同沥青的混合料路用性能的对比试验,结果表明,聚合物复合改性沥青的高低温性能及动力黏度优于高黏沥青A,排水沥青路面混合料路用性能优于开级配OGFC混合料的路用性能。

  3. Field test and research on vehicle load induced dynamic pore pressure in asphalt pavement%车载引起的沥青路面内动水压力现场试验研究

    Institute of Scientific and Technical Information of China (English)

    汤潍泽; 欧金秋; 崔新壮; 楼俊杰; 肖溟; 张炯; 黄丹; 侯飞

    2015-01-01

    In order to study the influence on moisture damage of asphalt pavement caused by dynamic pore pressure due to moving vehicle loads,and explore the time histories of dynamic stress and dynamic pore pressure in the pavement surface layers,the heat-resistant dynamic stress and pore pressure sensors were developed and used to measure the dynamic stresses and pore pressures in the field,and the field measured data of dynamic pore pressure was acquired. Based on the Biot’s consolidation theory,a numerical fluid-solid coupling simulation method reflecting mobile effect of wheel load was used to analyze the response of pavement under the actual condition.The time history of dynamic pore pressure in pavement was quantitatively analyzed.Numerical simulation results matched well with in situ test data.The pump-suction effect of dynamic pore pressure that continuously generated in pavement void under cyclical vehicle loads led to the reduce of the asphalt-aggregate bond strength and further triggered the moisture damage.This study verified the hydraulic drive mechanism of moisture damage,and provided a theoretical guild for the moisture damage research and pavement design.%为了研究移动车载引起的动水压力对沥青路面水损坏产生的影响,探究路面层内动应力变化及动水压力的长消规律,利用自主研制的耐高温动应力和动水压力传感器,对现场行车荷载引起的动应力及动水压力进行实测,获取了动水压力的实测数据;并且基于 Biot 固结理论,利用一种反映移动效应的车轮荷载数值模拟方法,对实测工况下路面情况进行了动态流固耦合分析,定量研究了路面层内的动水压力长消规律。发现现场实测与数值模拟结果基本一致。沥青路面在周期行车荷载作用下,路面空隙中不断产生动水压力的泵吸作用,导致沥青混合料强度下降,进而引发水损坏。该成果验证了水损坏的水力驱动机理,

  4. Evaluation of Colemanite Waste as Aggregate Hot Mix Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Nihat MOROVA

    2015-09-01

    Full Text Available In this study usability of waste colemanite which is obtained after cutting block colemanite for giving proper shape to blocks as an aggregate in hot mix asphalt. For this aim asphalt concrete samples were prepared with four different aggregate groups and optimum bitumen content was determined. First of all only limestone was used as an aggregate. After that, only colemanite aggregate was used with same aggregate gradation. Then, the next step of the study, Marshall samples were produced by changing coarse and fine aggregate gradation as limestone and colemanite and Marshall test were conducted. When evaluated the results samples which produced with only limestone aggregate gave the maximum Marshall Stability value. When handled other mixture groups (Only colemanite, colemanite as coarse aggregate-limestone as fine aggregate, colemanite as fine aggregate-limestone as coarse aggregate all groups were verified specification limits. As a result, especially in areas where there is widespread colemanite waste, if transportation costs did not exceed the cost of limestone, colemanite stone waste could be used instead of limestone in asphalt concrete mixtures as fine aggregate

  5. Studying asphalt binder fatigue pattern by using a dynamic shear rheometer

    Directory of Open Access Journals (Sweden)

    Oscar Javier Reyes Ortiz

    2011-01-01

    Full Text Available This article was aimed at determining fatigue test results regarding different types of binder when using a dynamic shear rheometer (DSR. The tests were carried out in stress conditions at 20ºC. The stress input signal was a constant amplitude, 1.59 Hz frequency sine wave. Asphalt binders B-13/22, B-40/50, B-60/70, B-80/00, B-150/200 and BM-3c (modified asphalt were studied. The test measured strain, complex modulus (G*, dissipated energy and dissipated energy ratio (DER with the number of cycles. Strain criteria were used for determining binder fatigue failure (DER. Failure was defined as the point at which (DER dropped 10% after peaking. Laws of asphalt fatigue were obtained from the strain and failure cycle results.

  6. Effect of Rubberized Bitumen Blending Methods on Permanent Deformation of SMA Rubberized Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Herda Yati Katman

    2016-01-01

    Full Text Available This study aims at comparing the permanent deformation of Stone Mastic Asphalt (SMA rubberized asphalt mixtures produced by the wet process. In this study, rubberized binders were prepared using two different blending methods, namely, continuous blend and terminal blend. To study the creep behaviour of control and rubberized asphalt mixtures, the dynamic creep test was performed using Universal Materials Testing Apparatus (UMATTA at different temperatures and stress levels. Zhou three-stage creep model was utilized to evaluate the deformation characteristics of the mixtures. In all test conditions, the highest resistance to permanent deformation is showed by the rubberized mixtures produced with continuous blend binders. This study also reveals that the permanent deformation of rubberized mixtures cannot be predicted based on the characteristics of the rubberized binders.

  7. Study of the Internal Mechanical response of an asphalt mixture by 3-D Discrete Element Modeling

    DEFF Research Database (Denmark)

    Feng, Huan; Pettinari, Matteo; Hofko, Bernhard

    2015-01-01

    for all the distinct elements. The dynamic modulus and phase angle from uniaxial complex modulus tests of the asphalt mixtures in the laboratory have been collected. A macro-scale Burger’s model was first established and the input parameters of Burger’s contact model were calibrated by fitting......In this paper the viscoelastic behavior of asphalt mixture was investigated by employing a three-dimensional Discrete Element Method (DEM). The cylinder model was filled with cubic array of spheres with a specified radius, and was considered as a whole mixture with uniform contact properties...... with the lab test data of the complex modulus of the asphalt mixture. The Burger’s contact model parameters are usually calibrated for each frequency. While in this research a constant set of Burger’s parameters has been calibrated and used for all the test frequencies, the calibration procedure...

  8. Study of normal and shear material properties for viscoelastic model of asphalt mixture by discrete element method

    DEFF Research Database (Denmark)

    Feng, Huan; Pettinari, Matteo; Stang, Henrik

    2015-01-01

    In this paper, the viscoelastic behavior of asphalt mixture was studied by using discrete element method. The dynamic properties of asphalt mixture were captured by implementing Burger’s contact model. Different ways of taking into account of the normal and shear material properties of asphalt...... mixtures have been reviewed. Two models, Model I and Model II, with different design parameters were developed and compared. For Model I, Burger’s model parameters in normal and shear direction were calibrated by using laboratory test results from Frequency Sweep Test performed in both normal and shear...... direction, respectively; while for Model II, the same calibrated parameters in the normal direction were used, but the values for the shear direction were chosen to be equal with the normal direction. The complex modulus of asphalt mixtures were predicted for both optimized models by conducting DE...

  9. Development of asphalts and pavements using recycled tire rubber. Phase 1, Technical feasibility. Technical progress report, September 1, 1994--August 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Bullin, J.A.; Davison, R.R.; Glover, C.J. [and others

    1996-06-01

    About 285 million tires are discarded every year; less than 100 million are currently being recycled, with the rest being placed in landfills and other waste sites. A solution to reduce the littering of the environment is to use ground tire rubber in road construction. Currently, about 27 million tons of asphalt are used each year in road construction and maintenance of the country`s 2 million miles of roads. If all of the waste tire rubber could be combined with asphalt in road construction, it would displace less than 6% of the total asphalt used each year, yet could save about 60 trillion Btus annually. Purpose of this project is to provide data needed to optimize the performance of rubber-asphalt concretes. The first phase is to develop asphalts and recycling agents tailored for compatibility with ground tire rubber. Chapter 2 presents results on Laboratory Testing and Evaluation: fractionate asphalt material, reblending for aromatic asphalts, verifying optimal curing parameters, aging of blends, and measuring ductilities of asphalt-rubber binders. Chapter 3 focuses on Evaluating Mixture Characteristics (modified binders). Chapter 4 covers Adhesion Test Development (water susceptibility is also covered). The final chapter focuses on the Performance/Economic Update and Commercialization Plan.

  10. Research and Application on Warm Technology of Asphalt Mixture on Soft Asphalt and Rock Asphalt Compound%基于软硬沥青复配的沥青混合料温拌技术的研究与应用

    Institute of Scientific and Technical Information of China (English)

    胡安宇; 张永平; 王飞

    2011-01-01

    On basis of soft asphalt and rock asphalt compound technology, warm asphalt mixture was made by use of soft asphalt and rock asphalt. The principle technology, technological process, design method of warm mix asphalt were presented; the road performance of the warm mixture was texted and the warm asphalt mixture was used to real engineering. Test and survey result indicated that warm mix asphalt almost have the same road performance compared with hot mix asphalt which have the same type of gradation, and the construction temperature can reduce 30℃, the temperature decrease scope was low with the spread paving and compaction process , the mixture was more easily to be compacted, the exhaust gas discharge level can be effectively reduced in mixing, spread paving and compaction process.%基于软硬沥青复配技术,实施沥青混合料的温拌配制.阐述该类温拌沥青混合料的技术原理、制备工艺和配合比设计关键;测试该类混合料的路用性能,并用于沥青路面工程铺筑.室内试验和现场检测结果表明,与同级配类型的、基质沥青配制的热拌沥青混合料相比,该类沥青混合料的高温稳定性和抗疲劳性略胜一筹,水稳定性相当;现场拌和温度可以降低30℃左右,摊铺和碾压过程中的降温幅度较低,更易压实;可以有效降低拌和、摊铺和压实过程中的废气排放水平.

  11. Exposure to ultrafine particles in asphalt work.

    Science.gov (United States)

    Elihn, Karine; Ulvestad, Bente; Hetland, Siri; Wallen, Anna; Randem, Britt Grethe

    2008-12-01

    An epidemiologic study has demonstrated that asphalt workers show increased loss of lung function and an increase of biomarkers of inflammation over the asphalt paving season. The aim of this study was to investigate which possible agent(s) causes the inflammatory reaction, with emphasis on ultrafine particles. The workers' exposure to total dust, polycyclic aromatic hydrocarbons, and NO(2) was determined by personal sampling. Exposure to ultrafine particles was measured by means of particle counters and scanning mobility particle sizer mounted on a van following the paving machine. The fractions of organic and elemental carbon were determined. Asphalt paving workers were exposed to ultrafine particles with medium concentration of about 3.4 x 10(4)/cm(3). Ultrafine particles at the paving site originated mainly from asphalt paving activities and traffic exhaust; most seemed to originate from asphalt fumes. Oil mist exceeded occupational limits on some occasions. Diesel particulate matter was measured as elemental carbon, which was low, around 3 microg/m(3). NO(2) and total dust did not exceed limits. Asphalt pavers were exposed to relatively high concentrations of ultrafine particles throughout their working day, with possible adverse health effects.

  12. Experimental Analysis on Rheological Properties of Modified Asphalt in Desert Area%荒漠地区改性沥青流变性能试验分析

    Institute of Scientific and Technical Information of China (English)

    沈宁; 杨三强

    2016-01-01

    为了研究荒漠地区两种常用沥青流变性能,采用DSR、BBR的试验方法分别对RTFOT短期老化前后沥青的流变参数进行对比分析,得出短期老化前后沥青性能排序。结果表明:高温下RTFOT前后沥青流变性能顺序为橡胶改性沥青>SBS改性沥青;低温下沥青RTFOT前流变性能顺序为SBS改性沥青>橡胶改性沥青,而沥青RTFOT后低温流变性能顺序为橡胶改性沥青>SBS改性沥青。研究表明在荒漠地区橡胶改性沥青的流变性能优于SBS改性沥青,短期老化提升了沥青抵抗流动变形的能力。%In order to study the theological properties of two kinds of asphalt used in desert area, the DSR and BBR test methods are used to compare and analyze the rheological parameters of asphalt before and after the short-term aging of RTFOT and obtain the asphalt performance sort before and after the short-term aging. Results show that, under high temperature, the asphalt rheological properties order before and after RTFOT is rubber modified asphalt> SBS modified asphalt, under low temperature, the asphalt rheological properties order before and after RTFOT is SBS modified asphalt> rubber modified asphalt, the rheological property order of asphalt at low temperature after RTFOT is rubber modified asphalt>SBS modified asphalt. Research shows that rheological property of rubber modified asphalt is better than that of SBS modified asphalt in desert region, and short-term aging improves the ability of asphalt to resist flow deformation.

  13. Asphalt emulsion radon barrier systems for uranium mill tailings: an overview of the technology

    Energy Technology Data Exchange (ETDEWEB)

    Baker, E.G.; Hartley, J.N.; Freeman, H.D.; Gates, T.E.; Nelson, D.A.; Dunning, R.L.

    1984-03-01

    Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, has developed an asphalt emulsion cover system to reduce the release of radon from uranium mill tailings. The system has been field tested at Grand Junction, Colorado. Results from laboratory and field tests indicate that this system is effective in reducing radon release to near-background levels (<2.5 pCi m/sup -2/s/sup -1/) and has the properties required for long-term effectiveness and stability. Engineering specifications have been developed, and analysis indicates that asphalt emulsion covers are cost-competitive with other cover systems. This report summarizes the technology for asphalt emulsion radon barrier systems. 59 references, 45 figures, 36 tables.

  14. Analysis of test method for anti cracking performance of asphalt mixtures based on Overlaytester%基于Overlaytester的沥青混合料抗裂性能试验方法分析

    Institute of Scientific and Technical Information of China (English)

    闫翔鹏; 阎肖宇

    2014-01-01

    Overlay tester 是一种简单快速的检测HMA ( Hot Mixture Asphalt )抗裂性能的方法,通过试验,结果与路面实际表现相关性很好。%The overlay tester is a rapid and practical experimental method , whose results all correlated well with the field performance .

  15. Characterization of long term field aging of polymer modified bitumen in porous asphalt

    NARCIS (Netherlands)

    Vliet, D. van; Erkens, S.; Leegwater, G.A.

    2012-01-01

    The effect of long term field aging on different types of polymer modified binders used in two-layer porous asphalt is studied using different test methods. Chemical and rheological tests are performed on samples taken from road sections at different moments in time in search of trends in long term

  16. Dynamic Properties of Footbridges: Influence of Asphalt Pavement and Support Conditions

    Directory of Open Access Journals (Sweden)

    Weber Benedikt

    2015-01-01

    Full Text Available Natural frequencies and damping ratios are important parameters in the design of footbridges against vibrations. Although not normally considered in calculations, non-structural elements such as the asphalt pavement and the supports can have a significant influence on the dynamic properties. In this article we present results from vibration tests conducted on four footbridges over the last few years covering a wide range of asphalt temperatures. The experiments show that both the natural frequencies and the damping ratios can change significantly with temperature. In one particular case, a variation in natural frequency of 25% has been observed between high and low asphalt temperatures. An additional damping of around 1% due to the asphalt pavement has been detected. To more clearly understand the experimental results, the bridges were also analysed numerically using a visco-elastic material for the asphalt. The analysis of the experimental results also revealed that other non-structural elements can have a large influence on dynamic properties of bridges. In two cases, the supports did not perform as expected and lead to surprising results.

  17. Design of Small Stone Asphalt Mixture based on Anti-skidding Performance

    Institute of Scientific and Technical Information of China (English)

    LI Rui; LI Yanwei; SHI Xin; LIU Zhongwan; YANG Jianbo; PEI Jianzhong

    2012-01-01

    Small stone asphalt mixture (SSAM) was designed by Bailey method and coarse aggregate voids-filling method.The optimum asphalt content was determined by Marshal test.Surface texture depth for SSAM with different voidage,and the BPN of SSAM and SMA before after wet track abrasion were measured.The experimental results indicate that the surface texture depth increases with the decreasing of asphalt aggregate ratio.The SSAM with the optimal asphalt content has a good skid resistance.BPN of asphalt mixture decreases with the increasing of wearing time,but the extent of reduction is different.The reduction rate of BPN for SSAM is smaller than that of SMA,indicating that SSAM has a good skid resistance attenuation capacity.Finally,the other properties of SSAM are also evaluated,showing that the splitting strength and modulus and SSAM are higher than those of SMA,and the other properties of SSAM,such as high-temperature performance and water stability can also satisfy the technical requirements.

  18. Laboratory and field evaluation of hot mix asphalt with high contents of reclaimed asphalt pavement

    Science.gov (United States)

    Van Winkle, Clinton Isaac

    Currently in Iowa, the amount of RAP materials allowed for the surface layer is limited to 15% by weight. The objective of this project was to develop quality standards for inclusion of RAP content higher than 15% in asphalt mixtures. To meet Superpave mix design requirements, it was necessary to fractionate the RAP materials. Based on the extensive sieve-by-sieve analysis of RAP materials, the optimum sieve size to fractionate RAP materials was identified. To determine if the higher percentage of RAP materials than 15% can be used in Iowa's state highway, three test sections with 30.0%, 35.5% and 39.2% of RAP materials were constructed on Highway 6 in Iowa City. The construction of the field test sections was monitored and the cores were obtained to measure field densities of test sections. Field mixtures collected from test sections were compacted in the laboratory in order to test the moisture sensitivity using a Hamburg Wheel Tracking Device. The binder was extracted from the field mixtures with varying amounts of RAP materials and tested to determine the effects of RAP materials on the PG grade of a virgin binder. Field cores were taken from the various mix designs to determine the percent density of each test section. A condition survey of the test sections was then performed to evaluate the short-term performance.

  19. Coprocessing Yanzhou coal with petroleum resid for preparing paving asphalt

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.; Li, Y.; Yang, J.; Liu, Z.; Chi, H. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

    2003-07-01

    Coprocessing Yanzhou coal with five types of petroleum resid for preparing high grade paving asphalt (HGPA) was investigated. The asphalt obtained was evaluated by 3 indexes: penetration, softening point and ductility. The thin layer chromatography (TLC) and NMR were used to characterise the asphalt. The results show that the properties of resid are crucial for the quality of asphalt. Under the experimental conditions, the resid with the lowest H/C ratio, highest aromatics content and shortest aliphatic side-chain produced asphalt with required quality for high grade paving asphalt used in China. Asphalt yield increased with H{sub 2} pressure and the quality of asphalt decreased with coal to resid ratio. 15 refs., 1 fig., 8 tabs.

  20. Incorporation de particules de bardeaux d'asphalte de postconsommation dans les enrobes bitumineux

    Science.gov (United States)

    Malo, Jean-Michel

    Every year, more than 200 000 tons of used residential roofing asphalt shingles are sent to landfills in Quebec. In order to reduce this amount, a research project funded by the 3RMCDQ and RECYC-QUÉBEC is ongoing at the LCMB at École de technologie supérieure (ÉTS) in Montreal. This project studies the feasibility of incorporating tear-off shingles particles in hot mix asphalt which could be used on Quebec roads. Currently, in Quebec, the ministry of Transportation (MTQ), allows the use of 5% of new asphalt shingles (factory reject) in the base course and 3% in the surface course, and tear-off shingles are not allowed. Incorporating new shingles particles is valued notably by the MTQ standardization for a reduction of binder in these mixes. As of now, the MTQ does not have a standard on the use of tear-off shingles, but the subject of experimental boards. The research done at ETS aim to characterize a standard base mix, GB20, and a standard surface mix, ESG-10, that contains tear-off shingles. Mixes containing different percentage of virgin binder were fabricated then tested on compaction capacity, on rutting resistance, on thermal cracking resistance (TSRST) and on complex modulus (E*). The amount of Virgin binder is calculated according to different percentage of effective binder from the shingles. This study has permitted to identify an optimal formula for both types of hot mix asphalt that were tested. Results show that for the standard ESG-10 surface mix, the possible contribution of tear-off asphalt shingles would be about 20%. For the standard GB-20 base mix, no reduction in the virgin binder may be considered for now when 5% of tear-off asphalt shingles are incorporated in the formula mix. In this case, further testing on complex modulus are recommended to obtain meaningful results that will determine if a reduction of the virgin binder would not be favorable.

  1. Theoretic computing model of combustion process of asphalt smoke

    Institute of Scientific and Technical Information of China (English)

    HUANG Rui; CHAI Li-yuan; HE De-wen; PENG Bing; WANG Yun-yan

    2005-01-01

    Based on the data and methods provided by research literature, dispersing mathematical model of combustion process of asphalt smoke is set by theoretic analysis. Through computer programming, the dynamic combustion process of asphalt smoke is calculated to simulate an experimental model. The computing result shows that the temperature and the concentration of asphalt smoke influence its burning temperature in approximatively linear manner. The consumed quantity of fuel to ignite the asphalt smoke needs to be measured from the two factors.

  2. 沥青混合料剪切性能影响因素研究%Research on the factors of shear performances for asphalt mixture

    Institute of Scientific and Technical Information of China (English)

    赵寻

    2014-01-01

    In order to study the influence of different factors on the shearing properties of asphalt mixture effect,based on the single penetration test and unconfined compression test,respectively on the asphalt type,aggregate gradation,asphalt content on asphalt mixture shear properties. The results show that:the type of asphalt will directly affect the shearing properties of asphalt mixture have,asphalt mixture of different asphalt types,which angle of internal friction ,cohesion C and shear strength of the three indicators of a larger difference,aggregate gradation has a great influence on shear properties of asphalt mixture,especially a great impact on cohesion C and shear strength of asphalt mixture.%采用单轴贯入试验和无侧限抗压试验,分别对沥青类型、级配类型、油石比对沥青混合料剪切性能的影响进行研究,结果表明:沥青的类型会直接影响到混合材料所具备的剪切性能,不同沥青类型的混合料的内摩擦角、粘聚力C以及剪切强度三个指标方面相差较大;级配类型对沥青混合料剪切性能具有很大的影响,特别是对沥青混合料的粘聚力C和剪切强度影响很大。

  3. 40 CFR 52.2054 - Control of asphalt paving material.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control of asphalt paving material. 52... asphalt paving material. (a) Notwithstanding any provisions to the contrary in the Pennsylvania Implementation Plan, the Pennsylvania Department of Transportation shall restrict the annual usage of asphalts...

  4. Full-Depth Asphalt Pavements for Parking Lots and Driveways.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    The latest information for designing full-depth asphalt pavements for parking lots and driveways is covered in relationship to the continued increase in vehicle registration. It is based on The Asphalt Institute's Thickness Design Manual, Series No. 1 (MS-1), Seventh Edition, which covers all aspects of asphalt pavement thickness design in detail,…

  5. Design and Performance of Hot Mix Asphalts with High Percentages of Reclaimed Asphalt: Approach followed in the Paramix Project

    OpenAIRE

    Pérez, F.; Rodriguez, M; Visscher, J.; Vanelstraete, A.; Bock, L.

    2004-01-01

    The use of reclaimed asphalt pavement (RA) in new asphalt pavements can provide important economical savings, while reducing the negative environmental impact. The European research project PARAMIX aims to improve the techniques for hot mix recycling in plant and cold mix in situ recycling, so as to increase the amount of reclaimed asphalt and develop competitive road pavement rehabilitation techniques. This paper deals with the design of hot mix asphalts for the project. The di...

  6. The Use of Polyethylene in Hot Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Mohammad T. Awwad

    2007-01-01

    Full Text Available The increase in road traffic during the last two decades in combination with an insufficient degree of maintenance due to shortage in funds has caused an accelerated and continuous deterioration of the road network in Jordan. To alleviate this process, several types of measures may be effective, e.g., securing funds for maintenance, improved roadway design, use of better quality of materials and the use of more effective construction methods. The use of polymer in asphalt mixture as a modifier started in the 80s of the last century and has been tested in a number of countries around the World. In this research, polyethylene as one sort of polymers is used to investigate the potential prospects to enhance asphalt mixture properties. The objectives also include determining the best type of polyethylene to be used and its proportion. Two types of polyethylene were added to coat the aggregate [High Density Polyethylene (HDPE and Low Density Polyethylene (LDPE]. The polymers were introduced to the mixture in two states (Grinded and not Grinded. Marshall mix design was used, first to determine the optimum bitumen binder content and then further to test the modified mixture properties. In total, 105 samples were prepared (21 samples were used to determine the binder content and the remaining samples were used to investigate the effect of modifying the asphalt mixtures. The optimum asphalt content was 5.4%. Seven proportions of polyethylene of each type and state by weight of the optimum binder content were selected to be tested (6, 8, 10, 12, 14, 16 and 18%. The tests include the determination of bulk density, stability and flow. Marshall mix design requires the determination of the percentages of air voids and air voids of mineral aggregate. The results indicated that grinded HDPE polyethylene modifier provides better engineering properties. The recommended proportion of the modifier is 12% by the weight of bitumen content. It is found to increase the

  7. Influence of reclaimed asphalt with polymer modified bitumen on properties of different asphalts for a wearing course

    NARCIS (Netherlands)

    Komačka, J.; Remišová, E.; Liu, G.; Leegwater, G.; Nielsen, E.

    2014-01-01

    A laboratory investigation was performed to study the effect of reclaimed asphalt with polymer modified bitumen on the properties describing asphalt performance. Three types of asphalts used for wearing courses in Europe (SMA 11, AC 11 and PA 8) were investigated. Five combinations of reclaimed asph

  8. Assessment of porous asphalt pavement performance: hydraulics and water quality

    Science.gov (United States)

    Briggs, J. F.; Ballestero, T. P.; Roseen, R. M.; Houle, J. J.

    2005-05-01

    The objective of this study is to focus on the water quality treatment and hydraulic performance of a porous asphalt pavement parking lot in Durham, New Hampshire. The site was constructed in October 2004 to assess the suitability of porous asphalt pavement for stormwater management in cold climates. The facility consists of a 4-inch asphalt open-graded friction course layer overlying a high porosity sand and gravel base. This base serves as a storage reservoir in-between storms that can slowly infiltrate groundwater. Details on the design, construction, and cost of the facility will be presented. The porous asphalt pavements is qualitatively monitored for signs of distress, especially those due to cold climate stresses like plowing, sanding, salting, and freeze-thaw cycles. Life cycle predictions are discussed. Surface infiltration rates are measured with a constant head device built specifically to test high infiltration capacity pavements. The test measures infiltration rates in a single 4-inch diameter column temporarily sealed to the pavement at its base. A surface inundation test, as described by Bean, is also conducted as a basis for comparison of results (Bean, 2004). These tests assess infiltration rates soon after installation, throughout the winter, during snowmelt, after a winter of salting, sanding, and plowing, and after vacuuming in the spring. Frost penetration into the subsurface reservoir is monitored with a frost gauge. Hydrologic effects of the system are evaluated. Water levels are monitored in the facility and in surrounding wells with continuously logging pressure transducers. The 6-inch underdrain pipe that conveys excess water in the subsurface reservoir to a riprap pad is also continuously monitored for flow. Since porous asphalt pavement systems infiltrate surface water into the subsurface, it is important to assess whether water quality treatment performance in the subsurface reservoir is adequate. The assumed influent water quality is

  9. An In-Depth Investigation into the Physicochemical, Thermal, Microstructural, and Rheological Properties of Petroleum and Natural Asphalts

    Directory of Open Access Journals (Sweden)

    Nader Nciri

    2016-10-01

    Full Text Available Over the last decade, unexpected and sudden pavement failures have occurred in several provinces in South Korea. Some of these failures remain unexplained, further illustrating the gaps in our knowledge about binder chemistry. To prevent premature pavement distress and enhance road performance, it is imperative to provide an adequate characterization of asphalt. For this purpose, the current research aims at inspecting the chemistry, microstructure, thermal, and physico-rheological properties of two types of asphalt, namely petroleum asphalt (PA and natural asphalt (NA. The binders were extensively investigated by using elemental analysis, thin-layer chromatography with flame ionization detection (TLC-FID, matrix-assisted laser desorption ionization time-of-fight mass spectroscopy (MALDI-TOF-MS, Fourier transform infrared spectroscopy (FT-IR, Raman spectroscopy (RS, Nuclear magnetic resonance spectroscopy (1H-NMR, ultraviolet and visible spectroscopy (UV-VIS, X-ray diffraction (XRD, scanning electron microscopy (SEM, thermogravimetric analysis (TGA, differential scanning calorimetry (DSC, penetration, softening point, ductility, and viscosity tests. The findings of this research have revealed the distinct variations between the chemical compositions, microstructures, and thermo-rheological properties of the two asphalts and provided valuable knowledge into the characteristics of the binders. Such insight has been effective in predicting the performance or distress of road pavement. This paper will, therefore, be of immediate interest to materials engineers in state highway agencies and asphalt industries.

  10. Assessments of low emission asphalt mixtures produced using combinations of foaming agents

    Science.gov (United States)

    Mohd Hasan, Mohd Rosli

    workability, and having a higher expulsion rate from the foamed binder compared to water as a foaming agent. The addition of foaming agents to the asphalt binder has also lowered the activation energy of the asphalt binder, which has high potential in lowering the energy demand during production processes. The foamed WMA mixture prepared at 100°C was found to have behavior comparable with the control Hot Mix Asphalt (HMA) prepared at 155°C in terms of coatability, workability and compactability. Based on the mixture performance tests, the foamed WMA has a comparable or better performance than the HMA in terms of resistance to moisture damage, permanent deformation, fracture cracking and thermal cracking. The application of nano-hydrated lime is efficient in enhancing the aggregate coatability and improving the bearing capacity of asphalt pavement to lower the rutting potential and moisture susceptibility of foamed WMA mixtures. Limitations for each of the related parameters are also reported in this dissertation for the lab production of foamed WMA mixtures using ethanol and NaHCO 3 as foaming agents. The specified values were made based on the binder test, service characteristics and performance of foamed WMA mixtures in order to yield a comparable or better performance than the control HMA. Field validations should be carried out to understand the overall performance and durability of the proposed foaming WMA.

  11. Analysis for Dynamic Response of Semi-Rigid Base Asphalt Pavement Based on APT Test%基于 APT 试验的半刚性基层沥青路面动力响应分析

    Institute of Scientific and Technical Information of China (English)

    庄传仪; 叶亚丽; 张宁

    2014-01-01

    In this article, the dynamic response of the semi-rigid asphalt pavement is studied through the acceleration and loading test on the full-scale test road , which provides the basis for the prediction and structural design of pavement performance .Through the APT test road construction with the two structures of cement stabilized macadam and lime-fly ash stabilized macadam , strain gauges , vertical stress sensors and temperature sensors are laid to make the real-time collection of the dynamic stress , strain and deflection of the pavement structure as well as the pavement temperature field , to analyze the correlation between the temperature and the responses of the structural dynamic strain and stress and also the calculation of the pavement layer moduli and mechanical response based on the FWD deflection basin .The research results are as follows .The tensile strain of semi-rigid base layer is less affected by temperature .The structural deflection is greatly affected by the thickness of the semi-rigid base .The thinner the semi-rigid base thickness is , the faster the decline of its modulus is .With the function of repeated loads , the declining rate of tensile strain of semi-rigid base layer increases first and then slowly decreases .In the early service ( less than 25 .6 million times of standard axle loads) , the modulus of the semi-rigid base decays slowly and when the pavement is loaded with 100 million cumulative equivalent standard axle loads , its modulus decays about 55%.%通过足尺试验路加速加载试验研究半刚性基层沥青路面的动力响应,为路面性能预估及结构设计提供依据。通过修筑水泥稳定碎石基层和二灰稳定碎石基层2种结构APT试验路,埋设水平应变仪、竖向压应力传感器和温度传感器,实时采集路面结构动应力、应变、弯沉和路面温度场,分析温度与结构动应变、应力响应的关系,开展基于FWD弯沉盆的路面结构层模量

  12. Recent rubber crumb asphalt pavement projects in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Soleyman, H.R. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering; Pulles, B.C.M.; Treleaven, L.B. [EBA Engineering Consultants Ltd., Edmonton, AB (Canada)

    2003-07-01

    Several countries around the world have been using rubber crumb (RC) for pavement applications for more than 20 years. The performance of asphalt pavements is enhanced by the use of recycled tires, which has the added advantage of solving the problem of tire disposal. In 2002, the Tire Recycling Management Association of Alberta (TRMA) and Alberta Transportation (AT) evaluated the feasibility and performance of an overlay using asphalt rubber (AR) pavement in Alberta. A partnership in the project was formed by AT, the City of Calgary, the City of Edmonton, and Strathcona County, where each one paved one section of a road with AR in conjunction with a section using conventional or other asphalt mixture types. The roads selected were: (1) 112 Avenue North West in Calgary, (2) 17 Street and Baseline Road in Strathcona County, (3) 137 Avenue in Edmonton, and (4) highway 630 in the vicinity of North Cooking Lake (Alberta Transportation). Two different AR pavement thicknesses were used to study the effects of overlay thicknesses on the performance of the overlay. The structural and functional factors were monitored before, during and after the construction of all sections. The preliminary evaluation of the application of AR in Alberta was presented, along with a summary of test results and performances of AR pavement sections. A full freeze-thaw cycle is required (Spring 2003) before the results of the analysis of the testing are known. The reduced thickness AR sections performed in a similar manner to those with full thickness AC sections. 10 refs., 5 tabs., 3 figs.

  13. Research on Alkaline Filler Flame-Retarded Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    HU Shuguang; ZHANG Houji; WANG Jiaolan

    2006-01-01

    Used as flame retardant of tunnel asphalt pavement, organic bromides produce a large amount of poisons and smoke in construction and flame retardation stage. The alkaline filler was found to replace mineral filler, and the flame-retarded asphalt mixtures were produced. Experimental results show that these asphalt mixtures are smoke restrained; the performances and construction technology of asphalt pavement are not influenced; also the alkaline filler is of low-price. So this kind of flame-retarded asphalt mixtures is suitable for tunnel pavement.

  14. Simulation of rheological behavior of asphalt mixture with lattice model

    Institute of Scientific and Technical Information of China (English)

    杨圣枫; 杨新华; 陈传尧

    2008-01-01

    A three-dimensional(3D) lattice model for predicting the rheological behavior of asphalt mixtures was presented.In this model asphalt mixtures were described as a two-phase composite material consisting of asphalt sand and coarse aggregates distributed randomly.Asphalt sand was regarded as a viscoelastic material and aggregates as an elastic material.The rheological response of asphalt mixture subjected to different constant stresses was simulated.The calibrated overall creep strain shows a good approximation to experimental results.

  15. Pneumoproteins and inflammatory biomarkers in asphalt pavers.

    Science.gov (United States)

    Ellingsen, Dag G; Ulvestad, Bente; Andersson, Lena; Barregard, Lars

    2010-09-01

    Pneumoproteins, biomarkers of systemic inflammation and endothelial activation were studied across a season in 72 asphalt pavers, 32 asphalt plant operators and 19 asphalt engineers. Smokers had lower concentrations of Clara cell protein (CC-16) and surfactant protein A, but higher concentrations of surfactant protein D, interleukin 6, C-reactive protein, fibrinogen and intercellular adhesion molecule (ICAM)-1 than non-smokers. Smokers reporting wheezing had lower mean CC-16 concentration than smokers not reporting wheezing (5.7 vs 8.6 microg l(-1); p = 0.05). Cholesterol, P-selectin and ICAM-1 were lower in pavers and operators at the end compared with the start of the season. This may be related to increased physical activity during the season.

  16. Aging Influence on Fatigue Characteristics of RAC Mixtures Containing Warm Asphalt Additives

    Directory of Open Access Journals (Sweden)

    Feipeng Xiao

    2010-01-01

    Full Text Available Aging is an important factor to affect the long-term performance of asphalt pavement. The fatigue life of a typical warm mix asphalt (WMA is generally related to various factors of rheological and mechanical properties of the mixture. The study of the fatigue behavior of the specific rubberized WMA is helpful in recycling the scrap tires and saving energy in terms of the conventional laboratory aging process. This study explores the utilization of the conventional fatigue analysis approach in investigating the cumulative dissipated, stiffness, and fatigue life of rubberized asphalt concrete mixtures containing the WMA additive after a long-term aging process. The aged beams were made with one rubber type (−40 mesh ambient crumb rubber, two aggregate sources, two WMA additives (Asphamin and Sasobit, and tested at 5 and 20ºC. A total of 55 aged fatigue beams were tested in this study. The test results indicated that the addition of crumb rubber extends the fatigue resistance of asphalt binder while WMA additive exhibits a negative effect. The study indicated that the WMA additive generally has an important influence on fatigue life. In addition, test temperature and aggregate source play an important role in determining the cumulative dissipated energy, stiffness, and fatigue life of an aged mixture.

  17. Development of an autonomous setup for evaluating self healing capability of asphalt mixtures

    NARCIS (Netherlands)

    Qiu, J.; Molenaar, A.A.A.; Van de Ven, M.F.C.; Wu, S.

    2012-01-01

    It is a well known fact that asphalt mixtures have self healing capabilities. Yet most of the self healing investigations are carried out using complex and time consuming fatigue tests. In order to investigate the self healing capability in a simple and efficient manner, a beam on elastic foundation

  18. Paving asphalt products exhibit a lack of carcinogenic and mutagenic activity.

    Science.gov (United States)

    Goyak, Katy O; McKee, Richard H; Minsavage, Gary D; McGowan, Claude; Daughtrey, Wayne C; Freeman, James J

    2011-10-01

    A paving asphalt and a vacuum residuum (derived from crude oil by atmospheric and subsequent vacuum distillation and used as a blend stock for asphalt) were tested in skin carcinogenesis assays in mice and in optimized Ames assays for mutagenic activity. In the skin cancer tests, each substance was applied twice weekly for 104 weeks to the clipped backs of groups of 50 male C3H mice. Neither the paving asphalt nor the vacuum residuum (30% weight/volume and 75% weight/weight in US Pharmacopeia mineral oil, respectively) produced any tumors. The positive control benzo[a]pyrene (0.05% w/v in toluene) induced tumors in 46 of 50 mice, demonstrating the effectiveness of the test method. Salmonella typhimurium tester strain TA98 was used in the optimized Ames assay to evaluate mutagenic potential. Dimethylsulfoxide (DMSO) extractions of the substances were not mutagenic when tested up to toxic limits. Thus, under the conditions of these studies, neither the paving asphalt nor the vacuum residuum was carcinogenic or mutagenic.

  19. Evaluation of plant-produced porous warm-mix asphalt mixture using LEADCAP additive

    Institute of Scientific and Technical Information of China (English)

    KIM Yongjoo; CHO Dongwoo; YANG Sunglin; KIM Yeongmin; KWON Sooahn; HWANG Sungdo

    2013-01-01

    Warm-mix asphalt (WMA) technology was applied for asphalt mixture,plant-produced porous WMA using LEADCAP additive (porous WMA-LEADCAP) test section was built and compacted at 30 ℃lower than porous hot-mix asphalt (porous HMA) test section.Marshall mix designs were conducted for porous WMA-LEADCAP mixture and porous HMA mixture in terms of Marshall stability,Cantabro loss and dynamic stability.The workability,compactablity and surface quality of porous WMA-LEADCAP pavement were investigated,and the engineering properties of plant-produced porous WMA-LEADCAP mixture and plant-produced porous HMA mixture were evaluated based on indirect tensile strength test and dynamic immersion test.Analysis result shows that LEADCAP additive does not affect polymermodified asphalt in terms of penetration,softening point,viscosity,ductility,toughness and tenacity.Porous WMA-LEADCAP pavement has similar field density,permeability and smoothness compared with standard porous HMA pavement.Plant-produced porous WMA-LEADCAP mixture is equivalent to plantproduced porous HMA mixture in indirect tensile strength,toughness and stripping resistance.4 tabs,4 figs,9 refs.

  20. Comparison and Evaluation Research on High Viscosity Asphalt Types of Drainage Asphalt Mixture%排水沥青混合料高粘沥青类型的对比和评价研究

    Institute of Scientific and Technical Information of China (English)

    丁志勇

    2016-01-01

    Viscous asphalt is the core of the drainage asphalt mixture material.In this research,the high viscosity asphalt was produced using star-shaped and linear SBS respectively,on this basis,the pavement performance of OGFC-1 3 drainage asphalt mixture was tested in the laboratory.It was found that the pavement performance of asphalt mixture made by the star-shaped SBS was better than that made by the linear SBS through the wheel rutting test,beam bending test,freeze-thaw splitting test and water dispersion test.%高粘沥青是排水沥青混合料的核心材料。文中采用星型和线型 SBS改性沥青制备高粘沥青,在此基础上,室内成型 OGFC-13排水沥青混合料,并对沥青混合料的路用性能进行研究。通过往复车辙轮碾压试验、低温弯曲梁试验、冻融劈裂试验和浸水飞散试验进行对比。结果表明,采用星型 SBS制备的排水沥青混合料各项路用性能均优于线型 SBS排水沥青混合料。

  1. Characteristics of asphalt mixes with FT additive

    Science.gov (United States)

    Štefunková, S.

    2012-03-01

    This article is focused on low-temperature asphalt mixture technologies using FT additive and RAP. The modern production and use of asphalt mixture technologies with reduced temperatures has many advantages. These advantages mainly help to save energy and the environment. Lower temperatures enable a reduction in energy consumption, a more acceptable working environment for workers, a reduction in negative environmental effects, such as greenhouse gas emissions, and an improvement in the workability of mixtures and a prolongation of their duration. This technology is currently becoming popular in many countries.

  2. Statistical Evaluation of Non-Agglomerating Coating for Granulated Natural Asphalt

    Directory of Open Access Journals (Sweden)

    Tjokorde Walmiki Samadhi

    2011-04-01

    Full Text Available Agglomeration of granulated Buton natural asphalt during storage is of major concern in its large-scale commercial application. This work develops a simple test method to evaluate the performance of agglomeration-resistant coating for granulated Buton asphalt, consisting of water-based polymeric primary coating and mineral-based secondary coating. The method uses a static load cell to measure the agglomerated granule count fraction under simulated storage conditions. A 24-1 fractional factorial experiment with two replications is employed to evaluate the effect of coating drying temperature, drying time, asphalt to secondary coating mass ratio, and secondary coating type on the agglomerated count fraction at ambient temperature and 60 oC. The test is able to measure a statistically significant increase in agglomeration resistance when the coating is applied, with an agglomerated fraction of 17.5% at 60 oC. The test identifies asphalt to secondary coating weight ratio as a significant factor, with an ANOVA p-value much lower than other effects. A decrease in this mass ratio from 5:1 to 5:2 increases the agglomeration, which is hypothesized to be attributed to the hydrated cementitious phase between granular external surfaces. More work is needed to identify the acceptable fraction of agglomerated granules.

  3. Performance Evaluation of Stone Mastic Asphalt and Hot Mix Asphalt Mixtures Containing Recycled Concrete Aggregate

    Directory of Open Access Journals (Sweden)

    Mohammad Saeed Pourtahmasb

    2014-01-01

    Full Text Available Environmental and economic considerations have encouraged civil engineers to find ways to reuse recycled materials in new constructions. The current paper presents an experimental research on the possibility of utilizing recycled concrete aggregates (RCA in stone mastic asphalt (SMA and hot mix asphalt (HMA mixtures. Three categories of RCA in various percentages were mixed with virgin granite aggregates to produce SMA and HMA specimens. The obtained results indicated that, regardless of the RCA particular sizes, the use of RCA to replace virgin aggregates increased the needed binder content in the asphalt mixtures. Moreover, it was found that even though the volumetric and mechanical properties of the asphalt mixtures are highly affected by the sizes and percentages of the RCA but, based on the demands of the project and traffic volume, utilizing specific amounts of RCA in both types of mixtures could easily satisfy the standard requirements.

  4. Microstructural Analysis and Rheological Modeling of Asphalt Mixtures Containing Recycled Asphalt Materials

    Directory of Open Access Journals (Sweden)

    Augusto Cannone Falchetto

    2014-09-01

    Full Text Available The use of recycled materials in pavement construction has seen, over the years, a significant increase closely associated with substantial economic and environmental benefits. During the past decades, many transportation agencies have evaluated the effect of adding Reclaimed Asphalt Pavement (RAP, and, more recently, Recycled Asphalt Shingles (RAS on the performance of asphalt pavement, while limits were proposed on the amount of recycled materials which can be used. In this paper, the effect of adding RAP and RAS on the microstructural and low temperature properties of asphalt mixtures is investigated using digital image processing (DIP and modeling of rheological data obtained with the Bending Beam Rheometer (BBR. Detailed information on the internal microstructure of asphalt mixtures is acquired based on digital images of small beam specimens and numerical estimations of spatial correlation functions. It is found that RAP increases the autocorrelation length (ACL of the spatial distribution of aggregates, asphalt mastic and air voids phases, while an opposite trend is observed when RAS is included. Analogical and semi empirical models are used to back-calculate binder creep stiffness from mixture experimental data. Differences between back-calculated results and experimental data suggest limited or partial blending between new and aged binder.

  5. NOx removal from vehicle emissions by functionality surface of asphalt road.

    Science.gov (United States)

    Chen, Meng; Liu, Yanhua

    2010-02-15

    This paper reported the potential of heterogeneous photocatalysis as an advanced oxidation technology for NO(x) removal from vehicle emissions by using TiO(2) as a photocatalyst immobilized on the surface of asphalt road. Based on asphalt road material porous characteristic, we utilized permeability technology to make asphalt nano-TiO(2) to be environmental protection materials. And then using scanning electron microscope, we observed the penetrating effect of TiO(2). The effect of surface friction, humidity and light intensity on NO(x) removal had been systematically investigated by the use of TiO(2) immobilized on the surface of asphalt road as photocatalytic environmental protection materials. In addition, the decontaminating effect was tested by contrast test in TiO(2) spraying section with non-spraying section, while the productions were used in road environment. Results of experiment revealed that decontaminating rate of the productions ranged from 6% to 12% this kind of photochemical catalysis environmental protection material has good environment purification function.

  6. Effects of Crumb Rubber Size and Concentration on Performance of Porous Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Altan Cetin

    2013-01-01

    Full Text Available The purpose of this study is to investigate the effect of size distribution and concentration of crumb rubber on the performance characteristics of porous asphalt mixture. The recycling of scrap tires in asphalt pavements appears as an important alternative providing a large-scale market. The characteristics of bitumen are very important with regard to service life of porous asphalt pavement. The experimental study consists of two main steps. Firstly, the mixture design was performed to determine the optimum bitumen content. In the latter step, the mixtures were modified by dry process using crumb rubber in three different grain size distributions of #4~#20, #20~#200, and #4~#200 and rubber content of 10%, 15%, and 20% as weight of optimum bitumen. The permeability, Cantabro abrasion loss, indirect tensile strength, moisture susceptibility, and resilient modulus tests were carried out on the specimens. Test results show that #20~#200 sized rubber particles reduced air voids and coefficient of permeability, while they increased the Cantabro abrasion loss. In general, increasing the crumb rubber size and content decreased the performance characteristics of the porous asphalt mixtures.

  7. NO{sub x} removal from vehicle emissions by functionality surface of asphalt road

    Energy Technology Data Exchange (ETDEWEB)

    Chen Meng, E-mail: chenmeng623@126.com [College of Traffic, Northeast Forestry University, 26 Hexing Road, Harbin 150040 (China); Liu Yanhua, E-mail: liuyanhua815@126.com [College of Wildlife Resources, Northeast Forestry University, 26 Hexing Road, Harbin 150040 (China)

    2010-02-15

    This paper reported the potential of heterogeneous photocatalysis as an advanced oxidation technology for NO{sub x} removal from vehicle emissions by using TiO{sub 2} as a photocatalyst immobilized on the surface of asphalt road. Based on asphalt road material porous characteristic, we utilized permeability technology to make asphalt nano-TiO{sub 2} to be environmental protection materials. And then using scanning electron microscope, we observed the penetrating effect of TiO{sub 2}. The effect of surface friction, humidity and light intensity on NO{sub x} removal had been systematically investigated by the use of TiO{sub 2} immobilized on the surface of asphalt road as photocatalytic environmental protection materials. In addition, the decontaminating effect was tested by contrast test in TiO{sub 2} spraying section with non-spraying section, while the productions were used in road environment. Results of experiment revealed that decontaminating rate of the productions ranged from 6% to 12% this kind of photochemical catalysis environmental protection material has good environment purification function.

  8. Impact of Freeze-Thaw Cycles on Compressive Characteristics of Asphalt Mixture in Cold Regions

    Institute of Scientific and Technical Information of China (English)

    SI Wei; LI Ning; MA Biao; REN Junping; WANG Hainian; HU Jian

    2015-01-01

    Low average temperature, large temperature difference and continual freeze-thaw (F-T) cycles have signiifcant impacts on mechanical property of asphalt pavement. F-T cycles test was applied to illustrate the mixtures’ compressive characteristics. Exponential model was applied to analyze the variation of compressive characteristics with F-T cycles; Loss ratio model and Logistic model were used to present the deterioration trend with the increase of F-T cycles. ANOVA was applied to show the signiifcant impact of F-T cycles and asphalt-aggregate ratio. The experiment results show that the compressive strength and resilient modulus decline with increasing F-T cycles; the degradation is sharp during the initial F-T cycles, after 8 F-T cycles it turns to gentle. ANOVA results show that F-T cycles, and asphalt-aggregate ratio have signiifcant inlfuence on the compressive characteristics. Exponential model, Loss ratio model and Logistic model are signiifcantly iftting the test data from statistics view. These models well relfect the compressive characteristics of asphalt mixture degradation trend with increasing F-T cycles.

  9. Laboratory research on rheological behavior and characterization of ultraviolet aged asphalt

    Institute of Scientific and Technical Information of China (English)

    吴少鹏; 朱国军; 陈筝; 刘至飞

    2008-01-01

    The influence of aging on the evolution of structural,morphological and rheological properties of neat asphalt was investigated by Fourier transform infrared(FTIR),atomic force microscopy(AFM) and dynamic shear rheometer(DSR),respectively.Asphalt was suffered under 20 W/m2 of UV radiant intensity and under the condition of aging time(0,48,96 and 144 h) with film thickness of 100 μm and film thickness of 50,100,200 and 500 μm after aging for 120 h,respectively,at certain UV radiant intensity 20 W/m2.Rheological results tested by DSR exhibit higher the complex shear(stiffness) modulus(G*) and lower phase angle(δ),compared to the virgin at the same test condition.The compositions analysis of asphalt before and after aging show an increase of carbonyl and sulfoxides,while a decrease of aromatic functional groups.With the increase of the component of asphaltene,obvious agglomerates of asphalten appear in neat asphalt surfaces after aging.

  10. Steady-State Creep of Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Alibai Iskakbayev

    2017-02-01

    Full Text Available This paper reports the experimental investigation of the steady-state creep process for fine-grained asphalt concrete at a temperature of 20 ± 2 °С and under stress from 0.055 to 0.311 MPa under direct tension and was found to occur at a constant rate. The experimental results also determined the start, the end point, and the duration of the steady-state creep process. The dependence of these factors, in addition to the steady-state creep rate and viscosity of the asphalt concrete on stress is satisfactorily described by a power function. Furthermore, it showed that stress has a great impact on the specific characteristics of asphalt concrete: stress variation by one order causes their variation by 3–4.5 orders. The described relations are formulated for the steady-state of asphalt concrete in a complex stressed condition. The dependence is determined between stress intensity and strain rate intensity.

  11. Microbial life in a liquid asphalt desert.

    Science.gov (United States)

    Schulze-Makuch, Dirk; Haque, Shirin; de Sousa Antonio, Marina Resendes; Ali, Denzil; Hosein, Riad; Song, Young C; Yang, Jinshu; Zaikova, Elena; Beckles, Denise M; Guinan, Edward; Lehto, Harry J; Hallam, Steven J

    2011-04-01

    Pitch Lake in Trinidad and Tobago is a natural asphalt reservoir nourished by pitch seepage, a form of petroleum that consists of mostly asphaltines, from the surrounding oil-rich region. During upward seepage, pitch mixes with mud and gases under high pressure, and the lighter portion evaporates or is volatilized, which produces a liquid asphalt residue characterized by low water activity, recalcitrant carbon substrates, and noxious chemical compounds. An active microbial community of archaea and bacteria, many of them novel strains (particularly from the new Tar ARC groups), totaling a biomass of up to 10(7) cells per gram, was found to inhabit the liquid hydrocarbon matrix of Pitch Lake. Geochemical and molecular taxonomic approaches revealed diverse, novel, and deeply branching microbial lineages with the potential to mediate anaerobic hydrocarbon degradation processes in different parts of the asphalt column. In addition, we found markers for archaeal methane metabolism and specific gene sequences affiliated with facultative and obligate anaerobic sulfur- and nitrite-oxidizing bacteria. The microbial diversity at Pitch Lake was found to be unique when compared to microbial communities analyzed at other hydrocarbon-rich environments, which included Rancho Le Brea, a natural asphalt environment in California, USA, and an oil well and a mud volcano in Trinidad and Tobago, among other sites. These results open a window into the microbial ecology and biogeochemistry of recalcitrant hydrocarbon matrices and establish the site as a terrestrial analogue for modeling the biotic potential of hydrocarbon lakes such as those found on Saturn's largest moon Titan.

  12. The use of asphalt in hydraulic engineering

    NARCIS (Netherlands)

    Van de Velde, P.A.; Ebbens, E.H.; Van Herpen, J.A.

    1985-01-01

    Asphalt products have been used in the Netherlands in hydraulic engineering for a long time on a large scale, especially after the great disaster in 1953 when a large part of western Holland was flooded by the sea. After the disaster a great number of dikes had to be repaired very quickly and this w

  13. Microbial Life in a Liquid Asphalt Desert

    Science.gov (United States)

    Schulze-Makuch, Dirk; Haque, Shirin; de Sousa Antonio, Marina Resendes; Ali, Denzil; Hosein, Riad; Song, Young C.; Yang, Jinshu; Zaikova, Elena; Beckles, Denise M.; Guinan, Edward; Lehto, Harry J.; Hallam, Steven J.

    2011-04-01

    Pitch Lake in Trinidad and Tobago is a natural asphalt reservoir nourished by pitch seepage, a form of petroleum that consists of mostly asphaltines, from the surrounding oil-rich region. During upward seepage, pitch mixes with mud and gases under high pressure, and the lighter portion evaporates or is volatilized, which produces a liquid asphalt residue characterized by low water activity, recalcitrant carbon substrates, and noxious chemical compounds. An active microbial community of archaea and bacteria, many of them novel strains (particularly from the new Tar ARC groups), totaling a biomass of up to 107 cells per gram, was found to inhabit the liquid hydrocarbon matrix of Pitch Lake. Geochemical and molecular taxonomic approaches revealed diverse, novel, and deeply branching microbial lineages with the potential to mediate anaerobic hydrocarbon degradation processes in different parts of the asphalt column. In addition, we found markers for archaeal methane metabolism and specific gene sequences affiliated with facultative and obligate anaerobic sulfur- and nitrite-oxidizing bacteria. The microbial diversity at Pitch Lake was found to be unique when compared to microbial communities analyzed at other hydrocarbon-rich environments, which included Rancho Le Brea, a natural asphalt environment in California, USA, and an oil well and a mud volcano in Trinidad and Tobago, among other sites. These results open a window into the microbial ecology and biogeochemistry of recalcitrant hydrocarbon matrices and establish the site as a terrestrial analogue for modeling the biotic potential of hydrocarbon lakes such as those found on Saturn's largest moon Titan.

  14. Asphalt fume dermal carcinogenicity potential: II. Initiation-promotion assay of Type III built-up roofing asphalt.

    Science.gov (United States)

    Freeman, James J; Schreiner, Ceinwen A; Beazley, S; Burnett, Donald M; Clark, Charles R; Mahagaokar, Suneeta; Parker, Craig M; Stewart, Christopher W; Swanson, Mark S; Arp, Earl W

    2011-10-01

    Clark et al. (accepted for publication) reported that a sample of field-matched fume condensate from a Type III built-up roofing asphalt (BURA) resulted in a carcinogenic response in a mouse skin bioassay, with relatively few tumor-bearing animals, long tumor latency and chronic skin irritation. This mouse skin initiation/promotion study was conducted to assess possible mechanisms, i.e., genotoxic initiation vs. tumor promotion subsequent to repeated skin injury and repair. The same Type III BURA fume condensate sample was evaluated in groups of 30 male Crl:CD1® mice by skin application twice per week (total dose of 50 mg/week) for 2 weeks during the initiation phase and for 26 weeks during the promotion phase. Positive control substances were 7,12-dimethylbenz(a)anthracene (DMBA, 50 μg applied once) as an initiator and 12-O-tetradecanoyl-13-acetate (TPA, 5 μg, applied twice weekly) during the promotion phase. During the 6 months of study with the asphalt fume condensate, eight skin masses were observed when tested for initiation, five of which were confirmed microscopically to be benign squamous cell papillomas. Only two papillomas were observed when tested for promotion. There was no apparent relationship between skin irritation and tumor development in this study. These results are more indicative of genotoxicity rather than a non-genotoxic mode of action.

  15. Study of the Raveling Resistance of Porous Asphalt Pavements Used in Sustainable Drainage Systems Affected by Hydrocarbon Spills

    Directory of Open Access Journals (Sweden)

    Jorge Rodriguez-Hernandez

    2015-12-01

    Full Text Available Permeable pavements are one of the most commonly-used sustainable drainage systems (SuDS in urban areas for managing stormwater runoff problems. Porous asphalt is widely used in surface layers of permeable pavement systems, where it can suffer from accidental oil spills from vehicles. Oil spills affect bituminous mixes through the solvent action of the hydrocarbons on the bitumen, reducing the raveling resistance of asphalt pavements. In order to assess the raveling resistance in porous asphalt pavements, the Cantabro abrasion test was performed on 200 test samples after applying controlled oil spills. Three different types of binders were used: conventional bitumen, polymer-modified bitumen and special fuel-resistant bitumen. After analyzing the results, it was concluded that the most suitable bitumen to protect against oil leakages is the polymer-modified one, which is far better than the other two types of bitumen tested.

  16. Technology Research and Engineering Practice of Asphalt Rubber Low-noise Asphalt Pavement%降噪环保沥青路面技术研究与工程实践

    Institute of Scientific and Technical Information of China (English)

    张志祥; 刘伟; 李小燕

    2011-01-01

    对橡胶沥青绿色降噪环保路面技术进行了研究,包括材料选择、配合比设计方法、性能验证等设计要点,采用复合车辙试验进行高温性能验证,提出了橡胶沥青降噪路面的设计方法流程;并通过自行开发的车载式轮胎/路面噪声测试仪,对各种路面类型的噪声进行了测试,验证了降噪路面的降噪效果。%In this paper,the application of asphalt rubber in porous low-noise asphalt pavement was studied,including materials selection,gradation selection,performance verification,also high-temperature performance was also verified using complex rutting test,and a design process of rubber asphalt low-noise asphalt pavement mixture was put forward.The tire/pavement noise of many kinds of pavement was tested with self developed OBSI,and the advantage of low-noise asphalt pavement was verified.

  17. Performance Characteristic of Cold Recycled Mixture with Asphalt Emulsion and Chemical Additives

    Directory of Open Access Journals (Sweden)

    Shaowen Du

    2015-01-01

    Full Text Available Three types of chemical additives were used to modify asphalt emulsion recycled mixture. These chemical additives include composite Portland cement (CPC, hydrated lime (HL, and a combination of hydrated lime and ground-granulated blast-furnace slag (GGBF. The influence of different additives on the recycled mixture performance was investigated by volumetric and strength tests, moisture susceptibility test, rutting resistance test, and low temperature bending test. To better understand its performance characteristic, the microstructure images of the recycled mixture were observed by environmental scanning electron microscope (ESEM. Test results demonstrate that the performance improvement of the emulsion recycled mixture depends on the types and content of chemical additives. Several recommendations are presented for the selection of chemical materials. Based on ESEM image analysis, the interface bonding mechanism is proposed to explain the performance characteristic of the recycled mixture with asphalt emulsion and cementitious materials.

  18. Temperature Characteristic of Asphalt Pavement Structure in Beijing Based on Temperature Survey of Test Road%北京地区沥青路面结构内部温度变化规律

    Institute of Scientific and Technical Information of China (English)

    韩丁丁; 张金喜; 魏建军

    2015-01-01

    为了掌握沥青路面温度变化规律,更加准确地指导沥青路面设计和对沥青路面病害的分析,选择北京地区某高速公路沥青路面,在路面结构内部埋设了温度测试设备,对沥青路面结构内部温度进行了跟踪监测和分析,并给出了北京地区路面结构内部温度极值的预测公式.结果表明:北京地区(实验路段中)沥青路面上面层底部全年最高温度为33.8℃,最低温度为-16.8℃.夏季沥青路面结构内部平均温度梯度为0.45℃/cm,冬季为-0.10℃/cm.路面结构内部温度降温速率在农历夏至前后最大,约0.6~1.2℃/h;路面在冬季长时间处于低温状况,降温速率在冬季较小,约0.2~0.4℃/h.北京地区1 a内沥青路面工作温度处于中低温期的时间约占85%左右.%In order to know the law of the temperature change of asphalt pavements, to design and precisely analyze the damaged asphalt pavements, temperature sensors were buried in a certain highway asphalt pavement in Beijing. And the sensors were used to track and analyze the internal temperature changes of the pavement structure. The results show that the temperature at the bottom of the upper surface varies from 33. 8 ℃ to -16. 8 ℃ during a year. The average temperature gradient of the pavement is 0. 45℃/cm in summer and -0. 10℃/cm in winter. The temperature decreasing rate of the pavement is about 0. 6~1. 2℃/h and the highest temperature decreasing rate occurs around the summer solstice of Chinese lunar calendar. The temperature decreasing rate is smaller than that of other seasons, and the record number is about 0. 2~0. 4℃/h. The working temperature of the asphalt pavement below 20℃ is about 85% within a year. A prediction formula of extreme of the internal temperature of the pavement structure was given in the paper.

  19. Parameter Characterisation of Asphalt Mixtures for Visco-Elastoplastic Analysis

    Institute of Scientific and Technical Information of China (English)

    陆阳; 廖敬梅; 廖军

    2002-01-01

    Asphalt mixtures exhibit strong viscous properties under repetitive loads. This phenomenon can be simulated in creep and recovery tests. By applying the visco-elastoplastic model proposed, data recorded in the tests are interpreted. It is emphasised that applicability of the visco-elastoplastic model depends on the proper method of characterising parameters involved in the constitutive equations. Since two or more strain components of elasticity and viscosity coexist during the loading or unloading, a measuring system of two loggers is introduced to decouple these components. Test data are analysed in three steps as elastic, visco-elastic and visco-plastic evaluations, using the records collected at the moment of unloading, during the periods of recovery and creep respectively. Factors that may influence the accuracy of data analysis are also discussed.

  20. Microstructural and rheological analysis of fillers and asphalt mastics

    Science.gov (United States)

    Geber, R.; Simon, A.; Kocserha, I.; Buzimov, A.

    2017-01-01

    Pavements are made of different grades of mineral aggregates and organic binder. The aggregates are sorted in different sizes and different amount which are mixed together with bitumen. The finest mineral fraction (ddolomite) which are used in Hungarian road constructions with the use of different techniques (particle size distribution, scanning electronmicroscopy tests, mercury intrusion porosimetry, BET specific surface tests, determination of hydrophobicity). After the tests of fillers, asphalt mastics were prepared and rheological examinations were obtained. These examinations served to observe the interaction and the effect of fillers. The stiffening effect of fillers and the causes of rutting were also investigated. Based on our results, it can be stated that particle size, hydrophobic properties and the amount of fillers highly affect the rheological properties of mastics.

  1. A Comparative Study on Properties of Malaysian Porous Asphalt Mixes with Different Bitumen Contents

    Directory of Open Access Journals (Sweden)

    Mohamad Yusri Aman

    2015-04-01

    Full Text Available Inadequate bitumen content in porous pavement construction may result in incomplete coating of aggregates which a thin bitumen film can oxidize rapidly resulting in premature failure of the pavement. This and presents the effects of porous asphalt prepared with 4.0% and up to 6.0% binder content with 0.5% increments binder. Bitumen penetration grade 60/70 and crushed granite were used in preparing the porous asphalt specimen. The porous asphalt mixes were compacted by applying 50 blows on each face using a Marshall Impact compactor. The specimens were tested for air voids, indirect tensile strength and water permeability and abrasion loss. The moisture sensitivity was assessed according to the AASHTO T283 procedures. The result shows that the increasing of bitumen content has decreased the, bulk density air voids, coefficient of permeability and abrasion loss values However, the Indirect Tensile Strength (ITS has significantly increased and this is a good indication to resistance against moisture sensitivity. It can be concluded that the increasing of bitumen content in porous asphalt has increased the thickness of binder coating around the aggregates. This results reduction in air voids and water permeability, on the other hands it increases resistance to disintegration and ITS value which give better resistance to moisture sensitivity of porous specimens.

  2. Strain transfer analysis of optical fiber based sensors embedded in an asphalt pavement structure

    Science.gov (United States)

    Wang, Huaping; Xiang, Ping

    2016-07-01

    Asphalt pavement is vulnerable to random damage, such as cracking and rutting, which can be proactively identified by distributed optical fiber sensing technology. However, due to the material nature of optical fibers, a bare fiber is apt to be damaged during the construction process of pavements. Thus, a protective layer is needed for this application. Unfortunately, part of the strain of the host material is absorbed by the protective layer when transferring the strain to the sensing fiber. To account for the strain transfer error, in this paper a theoretical analysis of the strain transfer of a three-layered general model has been carried out by introducing Goodman’s hypothesis to describe the interfacial shear stress relationship. The model considers the viscoelastic behavior of the host material and protective layer. The effects of one crack in the host material and the sensing length on strain transfer relationship are been discussed. To validate the effectiveness of the strain transfer analysis, a flexible asphalt-mastic packaged distributed optical fiber sensor was designed and tested in a laboratory environment to monitor the distributed strain and appearance of cracks in an asphalt concrete beam at two different temperatures. The experimental results indicated that the developed strain transfer formula can significantly reduce the strain transfer error, and that the asphalt-mastic packaged optical fiber sensor can successfully monitor the distributed strain and identify local cracks.

  3. Mortality from obstructive lung diseases and exposure to polycyclic aromatic hydrocarbons among asphalt workers

    Energy Technology Data Exchange (ETDEWEB)

    Burstyn, I.; Boffetta, P.; Heederik, D.; Partanen, T.; Kromhout, H.; Svane, O.; Langard, S.; Frentzel-Beyme, R.; Kauppinen, T.; Stucker, I.; Shaham, J.; Ahrens, W.; Cenee, S.; Ferro, G.; Heikkila, P.; Hooiveld, M.; Johansen, C.; Randem, B.G.; Schill, W. [University of Utrecht, Utrecht (Netherlands)

    2003-09-01

    Work in the asphalt industry has been associated with nonmalignant respiratory morbidity and mortality, but the evidence is not consistent. A historical cohort of asphalt workers included 58,862 men (911,209 person-years) first employed between 1913 and 1999 in companies applying and mixing asphalt in Denmark, Finland, France, Germany, Israel, the Netherlands, and Norway. The relations between mortality from nonmalignant respiratory diseases (including the obstructive lung diseases: chronic bronchitis, emphysema, and asthma) and specific chemical agents and mixtures were evaluated using a study-specific exposure matrix. Mortality from obstructive lung diseases was associated with the estimated cumulative and average exposures to polycyclic aromatic hydrocarbons and coal tar (p values of the test for linear trend=0.06 and 0.01, respectively). The positive association between bitumen fume exposure and mortality from obstructive lung diseases was weak and not statistically significant; confounding by simultaneous exposure to coal tar could not be excluded. The authors lacked data on smoking and full occupational histories. In conclusion, exposures to polycyclic aromatic hydrocarbons, originating from coal tar and possibly from bitumen fume, may have contributed to mortality from obstructive lung diseases among asphalt workers, but confounding and bias cannot be ruled out as an explanation for the observed associations.

  4. Field Test and Numerical Simulation of Dynamic Response of Semi-rigid Base Asphalt Pavement under Moving Vehicle Load%动载作用下半刚性基层沥青路面动力响应现场测试及数值模拟

    Institute of Scientific and Technical Information of China (English)

    张静; 魏连雨; 马士宾; 王涛

    2016-01-01

    Relying on the real project, the dynamic response of semi-rigid base asphalt pavement under moving vehicle load is studied based on the field test and 3D finite element simulation. First, the field test of the dynamic response of semi-rigid base asphalt pavement is conducted using fiber grating sensing technology. The dynamic theory, the moving vehicle load condition, the boundary condition and the structural parameters for the FE transient analysis are determined according to the field test result, and a 3D finite element model of the asphalt pavement is established. Then, the internal dynamic response feature of the pavement under different axle loads and material parameters are analysed. The result indicates that (1) under moving vehicle load, the stress state of the pavement tends to adverse with the decreasing of vehicle speed; ( 2 ) the longitudinal (the same as the driving direction) tensile strain is greater than the transverse tensile strain;(3) as the load increases, the volatility of strain response of the pavement is enhanced, and the tensile and compressive strains in the asphalt layer change alternately and dramatically;(4) the effect of surface modulus on the compressive strain on the top of subgrade is more significant than the base modulus, but the base modulus has a great impact on tensile strain at the bottom of surface.%依托实际工程,基于现场检测和三维有限元模拟技术,研究动载作用下半刚性基层沥青路面动力响应.首先,基于光纤光栅传感技术进行半刚性基层沥青路面动力响应现场测试,依据现场测试结果,确定有限元瞬态分析的动力学原理、 荷载条件、 边界条件及材料参数,建立沥青路面三维有限元模型;然后分析不同轴载及材料参数下路面结构内部的动力响应特征.结果表明,动载作用下,车速越低,路面结构受力状态越不利;纵向(行车方向)拉应变大于横向拉应变;随轴载的增大,路面结构的应变响

  5. Attempted DNA extraction from a Rancho La Brea Columbian mammoth (Mammuthus columbi): prospects for ancient DNA from asphalt deposits.

    Science.gov (United States)

    Gold, David A; Robinson, Jacqueline; Farrell, Aisling B; Harris, John M; Thalmann, Olaf; Jacobs, David K

    2014-02-01

    Fossil-bearing asphalt deposits are an understudied and potentially significant source of ancient DNA. Previous attempts to extract DNA from skeletons preserved at the Rancho La Brea tar pits in Los Angeles, California, have proven unsuccessful, but it is unclear whether this is due to a lack of endogenous DNA, or if the problem is caused by asphalt-mediated inhibition. In an attempt to test these hypotheses, a recently recovered Columbian mammoth (Mammuthus columbi) skeleton with an unusual pattern of asphalt impregnation was studied. Ultimately, none of the bone samples tested successfully amplified M. columbi DNA. Our work suggests that reagents typically used to remove asphalt from ancient samples also inhibit DNA extraction. Ultimately, we conclude that the probability of recovering ancient DNA from fossils in asphalt deposits is strongly (perhaps fatally) hindered by the organic compounds that permeate the bones and that at the Rancho La Brea tar pits, environmental conditions might not have been ideal for the general preservation of genetic material.

  6. 沥青砂动态剪切蠕变特性%Dynamic shear creep characteristics of asphalt mortar

    Institute of Scientific and Technical Information of China (English)

    王海朋; 张蓉; 张晓华; 毛成; 周水文

    2016-01-01

    为了解沥青砂的复杂力学行为,给沥青混合料细观力学研究提供数据支持,将几种沥青混合料的配合比转变为沥青砂的配比,采用自主研发的沥青砂成型装置及流变仪夹具获取沥青砂的动态剪切蠕变曲线,基于Burgers模型对蠕变曲线进行拟合,获取动态剪切荷载下沥青砂的黏弹性参数,分析黏弹性参数及松弛模量的变化规律。试验结果显示,Burgers模型对沥青砂动态剪切蠕变曲线具有较好的拟合效果。相同加载时间内,相比于AC-20级配沥青混合料,SMA-16级配沥青混合料蠕变变形量更大。橡胶沥青砂的抗剪切蠕变性能最优。沥青砂蠕变变形影响规律与混合料车辙变形一般影响规律相符。试验温度、沥青用量、沥青种类和级配类型均对沥青砂的黏弹性参数和松弛模量影响显著。%To consider the complex mechanical behavior of asphalt mortar and provide the data surpport for asphalt mix-ture micromechanics analysis,several asphalt mixture mixing ratios were transferred into asphalt mortar mixing ratios. Asphalt mortar molding device and discovery hybrid rheometer fixtures developed by ourselves were used to obtain the dynamic shear creep curves.Burgers model was used to fit the creep curves.The viscoelastic parameters of asphalt mor-tar under dynamic shear loading condition were obtained.The changing rules of the viscoelastic parameters and the re-laxation modulus were analyzed.Results showed that Burgers model had good fitting effect on dynamic shear creep curve of asphalt mortar.The creep deformation of SMA-16 corresponding asphalt mortar was larger than AC -20 within the same loading time.Rubber asphalt mortar had the optimal shear creep resistant properties.The asphalt mortar creep deformation had the same influence rules with the general influence rules of asphalt miture rutting deformation. Test temperature,asphalt contant,type of asphalt and aggregate

  7. Percolation Model of Graphite-modified Asphalt Concrete

    Institute of Scientific and Technical Information of China (English)

    MO Liantong; WU Shaopeng; LIU Xiaoming; CHEN Zheng

    2005-01-01

    The addition of graphite powder in conventional asphalt mixture can produced asphalt concrete with excellent electrical performance. Percolation theory was employed to discuss the relation between the conductivity and graphite content of graphite-modified asphalt concrete. It was found that the results of percolation model are consistent with experimental values. The percolation threshold of graphite-modified asphalt concrete is 10.94% graphite content account for the total volume of the binder phase consisting of asphalt and graphite. The critical exponent is 3.16, beyond the range of 1.6-2.1 for the standard lattice continuous percolation problem. Its reason is that the tunnel conduction mechanism originates near the critical percent content, which causes this system to be not universal. Tunnel mechanism is demonstrated by the nonlinear voltage-current characteristic near percolation threshold.The percolation model is able to well predict the formation and development of conductive network in graphite-modified asphalt concrete.

  8. An Improvement in Electrical Properties of Asphalt Concrete

    Institute of Scientific and Technical Information of China (English)

    WU Shao-peng; MO Lian-tong; SHUI Zhong-he; XUAN Dong-xing; XUE Yong-jie; YANG Wen-feng

    2002-01-01

    Materials such as Koch AH - 70, basalt aggregate, limestone powder and graphite particles were used to prepare conductive asphalt concrete, which is a new type of multi functional concrete. The mix proportion by weight was shown as follows. Fineaggregates (2.36-4.75 mm):fine aggregates (< 2.36mm): limestone powder: asphalt = 120:240: 14:30. The content of added graphite particles ranged from 0% to 20% ( by the Special weight of asphalt concerte). A conductive asphalt concrete with a resistivity around 10-103·Ωm was obtained.attention was paid to the effects of graphite content, graphite physical-chemical properties, asphalt content and temperature on the resistivity. Furthermore, an attempt was made to develop an electrically conductive model for asphalt concrete.

  9. The effect of cyclic hardening on fatigue properties of modified asphalt

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The phenomenon of cyclic hardening is observed in fatigue tests of modified asphalt controlled by low strain/stress level and it is not clear how the phenomenon affects the fatigue properties of binders. The special time weep tests were performed to investigate the point. Tests results indicate that the cyclic hardening is caused by the rearrangement of molecules in binders, and it can make the inner structure of binders getting stable and increase the fatigue properties of asphalt binders. But fatigue damage occurs when fatigue tests start, no matter the phenomenon of cyclic hardening happens or not. If the controlled load is low, the effect of rearrangement of molecules on material is beyond the effect of fatigue damage so that the cyclic hardening can be observed. When the load conditions get worse, the effect of slight fatigue damages produced in hardening stage will show.

  10. Influencing Factors of Compression Strength of Asphalt Mixture in Cold Region%寒区沥青混合料抗压强度影响因素

    Institute of Scientific and Technical Information of China (English)

    韦佑坡; 马骉; 司伟

    2012-01-01

    针对寒区低温特点,对沥青混合料进行室内单轴压缩试验,分析温度、油石比、沥青种类和级配对混合料抗压强度的影响.结果表明,混合料抗压强度随温度的升高而降低;对比不同最大公称粒径的沥青混合料的抗压强度可知,SBR改性AC - 16混合料的抗压强度高于AC - 13;存在对应于抗压强度达到最大值时的最佳油石比,约在6.0%~7.0%之间;SBR改性沥青混合料的低温抗压性能明显优于l30#道路石油沥青混合料.混合料抗压强度值的对数与温度及油石比的关系符合二元一次函数关系.用SPSS相关分析方法分析各影响因素对混合料抗压特性的影响程度可知,温度和沥青种类对抗压强度影响较大.%Aimed at the climate feature of low temperature in cold region, the influence of temperature, asphalt-aggregate ratio, asphalt types and aggregate gradation on the compression strength of asphalt mixture was analysed by indoor uniaxial compression test. The results show that (1) the compressive strength become lower with the increase of temperature; (2) based on comparing strengths of asphalt mixture in different nominal maximum sizes of aggregate, the compression strength of SBR modified AC-16 asphalt mixture is better than that of AC-13; (3) corresponds to maximum compressive strength of asphalt mixture, there exists the optimum asphalt-aggregate ratio between 6. 0% -7. 0% ; (4) the compressive properties of SBR modified asphalt mixture is superior to that of paving asphalt mixture No. 100 under low temperature; (5) the relation of the logarithm of the compression strength with temperature and asphalt-aggregate ratio approximately obeys two-variable linear function. The results also revealed that temperature and asphalt types have greatly affect on compression strength of asphalt mixture among influencing factors based on correspondence analysis of SPSS.

  11. Bone Glue Modified Asphalt: A Step towards Energy Conservation and Environment Friendly Modified Asphalts.

    Science.gov (United States)

    Rizvi, Hashim Raza; Khattak, Mohammad Jamal; Gallo, August A

    2014-01-01

    Asphalt has been modified for the past several decades using various additives, including synthetic polymers. Polymer modification improves structural and engineering characteristics of the binder, which is a result of improvement in rheological characteristics of binder as well as its adhesion capability with the aggregate. Such enhancement inevitably enhances the performance characteristics of hot mix asphalts (HMA) such as fatigue life, resistance to rutting, and thermal cracking. Even though polymer-modified HMA is popular in North America and European countries, its use is still limited in developing countries of Southeast Asia due to high costs associated with its manufacturing, processing, and energy consumption. In this study, a new kind of asphalt modifier derived from animal wastes, such as bones, hides, and flesh commonly known as Bone Glue, is studied. This biomaterial which is a by-product of food and cattle industries is cheap, conveniently available, and produced locally in developing countries. The results of the research study showed that the bone glue can easily be mixed with asphalt without significantly altering the asphalt binder's viscosity and mixing and compaction temperatures of HMA. Additionally, improvements in complex shear modulus for a range of temperatures were also determined and it was found that complex shear modulus was improved by bone glue modification.

  12. Detection of asphalt pavement cracks using remote sensing techniques

    Science.gov (United States)

    Mettas, Christodoulos; Agapiou, Athos; Themistocleous, Kyriacos; Neocleous, Kyriacos; Hadjimitsis, Diofantos G.

    2016-10-01

    Deterioration of asphalt road pavements is inevitable throughout its life cycle. There are several types of deterioration that take place on these surfaces, like surface defects and deformations. One of the most common asphalt defects is cracking. Fatigue, transverse, longitudinal, reflective, edge, block and slippage are types of cracking that can be observed anywhere in the world. Monitoring and preventative/periodic maintenance of these types of wears are two very important actions that have to take place to avoid "costly" solutions. This paper aims to introduce the spectral characteristics of uncracked (healthy) and cracked asphalt surfaces which can give a new asphalt crack index. This is performed through remote sensing applications in the area of asphalt pavements. Multispectral images can be elaborated using the index to enhance crack marks on asphalt surfaces. Ground spectral signatures were acquired from both uncracked and cracked asphalted areas of Cyprus (Limassol). Evaluation separability indices can be used to identify the optimum wavelength regions that can distinguish better the uncracked and cracked asphalt surfaces. The results revealed that the spectral sensitivity for the enhancement of cracked asphalt was detected using the Euclidean, Mahalanobis and Cosine Distance Indices in the Vis range (approximately at 450 nm) and in the SWIR 1 range (approximately at 1750 nm).

  13. The Effect of Morphological Characteristic of Coarse Aggregates Measured with Fractal Dimension on Asphalt Mixture’s High-Temperature Performance

    Directory of Open Access Journals (Sweden)

    Hainian Wang

    2016-01-01

    Full Text Available The morphological properties of coarse aggregates, such as shape, angularity, and surface texture, have a great influence on the mechanical performance of asphalt mixtures. This study aims to investigate the effect of coarse aggregate morphological properties on the high-temperature performance of asphalt mixtures. A modified Los Angeles (LA abrasion test was employed to produce aggregates with various morphological properties by applying abrasion cycles of 0, 200, 400, 600, 800, 1000, and 1200 on crushed angular aggregates. Based on a laboratory-developed Morphology Analysis System for Coarse Aggregates (MASCA, the morphological properties of the coarse aggregate particles were quantified using the index of fractal dimension. The high-temperature performances of the dense-graded asphalt mixture (AC-16, gap-graded stone asphalt mixture (SAC-16, and stone mastic asphalt (SMA-16 mixtures containing aggregates with different fractal dimensions were evaluated through the dynamic stability (DS test and the penetration shear test in laboratory. Good linear correlations between the fractal dimension and high-temperature indexes were obtained for all three types of mixtures. Moreover, the results also indicated that higher coarse aggregate angularity leads to stronger high-temperature shear resistance of asphalt mixtures.

  14. The Effect of High RAP and High Asphalt Binder Content on the Dynamic Modulus and Fatigue Resistance of Asphalt Concrete

    OpenAIRE

    Tomlinson, Christopher

    2013-01-01

    This thesis investigates the effects of using various percentages of RAP and asphalt binder contents on the dynamic modulus and fatigue resistance of asphalt concrete. Two RAP percentages (20% and 40%) and three binder percentages (plant-mixed, plant-mixed + 0.5%, and plant-mixed + 1.0%) were evaluated. A Superpave gyratory compactor and an asphalt vibratory compactor were used to prepare dynamic modulus samples and fatigue beam samples at 7% air voids. Three replicate samples for each percen...

  15. Effects of Sasobit® content on the rheological characteristics of unaged and aged asphalt binders at high and intermediate temperatures

    Directory of Open Access Journals (Sweden)

    Ali Jamshidi

    2012-08-01

    Full Text Available This paper describes the rheological properties of PG64, PG70, and PG76 asphalt binders blended with different Sasobit® contents. The rheological properties of the Sasobit®-modified binders were characterized after being subjected to different aging conditions using the dynamic shear rheometer (DSR and rotational viscometer (RV according to SuperpaveTM test protocols. The results indicated that the characterization of aging in terms of the Aging Index (AI depends on the rheological property of the asphalt binder selected for use in evaluating aging, the amount of Sasobit®, the binder type, and the temperature range. Linear relationships between failure temperatures of unaged and short-term-aged asphalt were observed for three binder types. Design charts were developed to select the appropriate Sasobit® content as a function of temperature, taking into consideration the stiffening effects of Sasobit®, using the SuperpaveTM fatigue factor and asphalt mix construction temperatures.

  16. The Use of Steel Works Crushed Slag (Lidonit in the Preparation of Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Gh. Gugiuman

    2004-01-01

    Full Text Available The high costs of the quarry crushed aggregates (producer costs to which additional railroad transport costs are taken into account result in the fact that at large distance away from quarry lesser amounts of chippings and crushing sands are provided only. The initiation of the crushed aggregates production manufactured out of steelworks crushed slag. Lidonit, at a competitive delivering price, has led to the first series of laboratory tests. In the first stage two asphalt concrete mixtures were made in cube-shaped and cylinder-shaped (Marshall test-tubes on which physical and mechanical characteristic values are determined. The results of these first tests outlined the real opportunity of using these products in supplying the roads and streets with asphalt mix for pavements.

  17. Development of a stress-mode sensitive viscoelastic constitutive relationship for asphalt concrete: experimental and numerical modeling

    Science.gov (United States)

    Karimi, Mohammad M.; Tabatabaee, Nader; Jahanbakhsh, H.; Jahangiri, Behnam

    2016-11-01

    Asphalt binder is responsible for the thermo-viscoelastic mechanical behavior of asphalt concrete. Upon application of pure compressive stress to an asphalt concrete specimen, the stress is transferred by mechanisms such as aggregate interlock and the adhesion/cohesion properties of asphalt mastic. In the pure tensile stress mode, aggregate interlock plays a limited role in stress transfer, and the mastic phase plays the dominant role through its adhesive/cohesive and viscoelastic properties. Under actual combined loading patterns, any coordinate direction may experience different stress modes; therefore, the mechanical behavior is not the same in the different directions and the asphalt specimen behaves as an anisotropic material. The present study developed an anisotropic nonlinear viscoelastic constitutive relationship that is sensitive to the tension/compression stress mode by extending Schapery's nonlinear viscoelastic model. The proposed constitutive relationship was implemented in Abaqus using a user material (UMAT) subroutine in an implicit scheme. Uniaxial compression and indirect tension (IDT) testing were used to characterize the viscoelastic properties of the bituminous materials and to calibrate and validate the proposed constitutive relationship. Compressive and tensile creep compliances were calculated using uniaxial compression, as well as IDT test results, for different creep-recovery loading patterns at intermediate temperature. The results showed that both tensile creep compliance and its rate were greater than those of compression. The calculated deflections based on these IDT test simulations were compared with experimental measurements and were deemed acceptable. This suggests that the proposed viscoelastic constitutive relationship correctly demonstrates the viscoelastic response and is more accurate for analysis of asphalt concrete in the laboratory or in situ.

  18. 基于DIC方法的沥青混合料断裂机理研究%Study on Split Mechanism of Asphalt Mixture Based on Dic Method

    Institute of Scientific and Technical Information of China (English)

    崔亚楠; 陈超

    2016-01-01

    Cracking is one of the early damage types for asphalt pavement ,the bending fracture feature about rubber powder modified asphalt mixture and normal asphalt mixture beam have been studied by the three-point bending beam test ,the deformation and damage progress of asphalt mix‐ture beam have been record by CCD ,furthermore ,the Digital Image Correlation (DIC ) method has used to study the displacement and deformation field of asphalt mixture beam in this article .The result of the test shows that :the asphalt、boundary character between asphalt and aggregate、loading rate are significant factors affect asphalt mixture property .It is concluded DIC method is a practical and an eco‐nomical method for studying the deformations of asphalt mixtures .%开裂是沥青路面早期破坏主要形式之一。为研究沥青混合料的断裂性能,对胶粉改性沥青混合料小梁进行三点弯曲试验,利用CCD摄像头跟踪拍摄了沥青混合料小梁变形破坏的全过程,并利用数字图像相关技术(DIC )计算了弯曲过程中小梁的变形及应变云图。结果表明:沥青混合料的抗弯曲断裂性能取决于沥青砂浆、沥青与骨料间的界面特性和加载速率。DIC方法是一种测试沥青混合料变形破坏规律实用而经济的方法。

  19. Key Technology of Asphalt Pavement Hot-In-Place Recycling%沥青路面就地热再生关键技术

    Institute of Scientific and Technical Information of China (English)

    游新宇

    2014-01-01

    沥青路面就地热再生技术已成为沥青路面维修改造的主要方法之一。以就地热再生技术为研究对象,结合室内试验与实际工程,对原路面调查与评价、回收沥青以及再生剂的选择、新旧沥青的掺配性能试验、马歇尔配合比的设计等关键技术进行了研究,所得研究成果可有效指导沥青路面就地热再生技术的应用。%The hot-in-place recycling technology of asphalt pavement has been one of the main methods for asphalt pavement reconstruction. Taken the hot-in-place recycling technology as the research ob-ject, the article studies the key technologies such as the survey and evaluation of the original road, as-phalt recovery and regeneration agent selection, the old and new asphalt mixing performance test, Mar-shall asphalt mixture design, and so on. Combined with laboratory tests and practical projects,the results can guide the hot-in-place recycling technology application of asphalt pavement effectively.

  20. Ethanol based foamed asphalt as potential alternative for low emission asphalt technology

    OpenAIRE

    Mohd Rosli Mohd Hasan; Zhanping You

    2016-01-01

    Foamed asphalt typically relies on water as a foaming agent because water becomes gaseous at elevated temperatures, generating numerous tiny bubbles in the asphalt and causing spontaneous foaming. In this study, ethanol was used as a potential alternative to water as a foaming agent. Ethanol is expected to be a physical blowing agent in the same manner as water, except it requires less energy to foam due to its 78 °C boiling point. This study compares the performance of water and ethanol as f...

  1. The Fuzzy Logic Model for the Prediction of Marshall Stability of Lightweight Asphalt Concretes Fabricated using Expanded Clay Aggregate

    Directory of Open Access Journals (Sweden)

    Sercan SERİN

    2014-07-01

    Full Text Available In the study, predictability of Marshall Stability (MS of light asphalt concrete that fabricated using expanded clay and had varied mix properties with Fuzzy Logic (FL were researched. With this aim, asphalt concrete samples that added expanded clay aggregate (EC in accordance with gradation determined in Highway Technical Specification, had different percentage of bitumen (POB (4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5% and unit weight (UW (1,75–1,87 (gr/cm3 were prepared and determined Marshall stabilities with Marshall test

  2. Assessment of Impact of the Rheological Parameters Change on Sensitivity of the Asphalt Strain Based on the Test Results / Ocena Wpływu Zmiany Parametrów Reologicznych Na Wrażliwość Deformacji Mieszanek Mineralno - Asfaltowych Na Podstawie Wyników Badań

    Science.gov (United States)

    Kurpiel, Artur; Wysokowski, Adam

    2015-03-01

    The creep test under the static loading, that allows to determine rheological properties of asphalt based on the creep curve, is the most effective test nowadays. Applied loads are non-destructive and allow to observe the course of the strain after the test load. The test can be carried out on compressing, shearing, bending as well as on triaxial test, that depends on the applied apparatus implementing different intensity [1, 2, 3, 4, 5, 6]. Based on the creep test, the stress of different properties can be specified. Among them there are valuable rheological properties based on selected viscoelascity models [1]. The properties of the viscoelascity models are relevant indexes depicting resistance to deformation. They can be used to forecast the wheel-truck in the accepted rheological model [1]. In this article it is shown the impact of different rheological properties of the viscoelacity model on the wheel-truck as well as the impact of different properties on shape and the course of the creep curve. The asphalt mixtures presented in this article are characterized by variable rheological properties. It is therefore difficult to determine which property mostly affects the size of the strain. However, the authors of this article attempted to analyse the change of the asphalt strain value of the different variables in particular rheological model, called Bürgers's model. Badanie pełzania pod obciążeniem statycznym jest obecnie najbardziej efektywnym badaniem pozwalającym na określenie reologicznych parametrów mieszanek mineralno - asfaltowych na podstawie krzywej pełzania. Stosowane obciążenia mają poziom nieniszczący i pozwalają na obserwację przebiegu odkształceń w czasie również po odciążeniu. Badanie może być realizowane przy ściskaniu, ścinaniu, rozciąganiu i zginaniu, a także w zakresie trójosiowym, w zależności od stosowanego aparatu realizującego zadany schemat naprężeń [1, 2, 3, 4, 5, 6]. Na podstawie badania pełzania mo

  3. Analysis of Temperature-Dropping Characteristics of Warm-Mix Asphalt and Hot-Mix Asphalt%温拌及热拌沥青混合料降温特性分析

    Institute of Scientific and Technical Information of China (English)

    侯曙光

    2011-01-01

    为研究热拌及温拌沥青混合料降温特性,采用车辙板试件进行试验,分别在110℃和130℃初始温度条件下,测试热拌沥青混合料、“路博”温拌沥青混合料和“Sasobit”温拌沥青混合料的降温特性,试验结果表明:混合料初始温度越高,降温速率越快,初始温度为110℃和130℃的车辙板经25 min后温度接近,分别为66℃和68℃;不同类型混合料降温速率不同,当初始温度为110℃时,热拌混合料降温最快,“Sasobit”温拌沥青混合料降温速率居中,“路博”温拌混合料降温速率最小,经35 min后,3种沥青混合料的温度损失分别为53℃、51℃和49℃.%In order to research on the temperature-dropping characteristics of warm-mix and hot-mix asphalt, in this paper some rutting test panels are used as specimens to determine the temperature-dropping characteristics of hot-mix asphalt(HMA) , warm-mix asphalt(WMA) with warmly mixing agent "Lo-Bo" and warm-mix asphalt with warmly mixing agent "Sasobit" under the conditions with initial temperatures of 110℃ and 130℃. The test results indicate that the higher initial temperature is, the higher temperature-dropping rate is. After 25 min the temperatures of rutting test panels with initial temperatures of 110℃ and 130℃ are close to each other and are in 66℃ and 68℃ separately. The temperature-dropping rates of different types of mixtures are not the same. When the initial temperature is in 110℃ , the tempea-ture-dropping rate of hot-mix asphalt is highest, the temperature-dropping rate of warm-mix asphalt added with "Sasobit" is in the middle, and the temperature-dropping rate of warm-mix asphalt added with "Lu-Bo" is lowest. After 35 min, the temperatures of the three types of asphalt mixtures have fallen by 53℃ , 51℃ and 49℃ separately.

  4. Effect of Reclaimed Asphalt Pavement on the Properties of Asphalt Mixtures%RAP对再生沥青混合料马歇尔指标的影响

    Institute of Scientific and Technical Information of China (English)

    A.Hussain; 邱延峻

    2012-01-01

    An experimental study was presented to eveluate the effect of the types and percentages of RAP on the Marshall performance index of asphalt mixtures.Adopting two different virgin aggregates(Limestone and Quartzite)and two different RAP sources(Nowshera and Mandra),preparing the Hot Mixture Asphalt Marshall specimens respectively,testing the different RAP ratio(0% ~ 100%)and different types of asphalt mixture of air voids,asphalt saturation,voids of mineral aggregate,Marshall stability,flow value,density and other index.The results show that mixtures containing RAP showed high stability and the stability increased with the increase in RAP content.%研究了旧沥青混合料(RAP)的种类及掺量对再生沥青混合料马歇尔指标的影响.以2种新集料(石灰岩和石英岩)及2种旧沥青混合料(Nowshera和Mandra)制备的集料,分别配制成热拌沥青混合料(HMA)的马歇尔试件,测试了不同RAP掺量(0% ~100%)及不同RAP种类的沥青混合料的空隙率、沥青饱和度、矿料间隙率、马歇尔稳定度、流值及密度等指标.试验表明:含有RAP的混合料具有更高的稳定度值,且稳定度随着RAP含量的增加而增大.

  5. Including asphalt cooling and rolling regimes in laboratory compaction procedures

    NARCIS (Netherlands)

    Bijleveld, F.R.; Doree, A.G.; Kim,

    2014-01-01

    Given the various changes occurring in the asphalt construction industry, improved process and quality control is becoming essential. The significance of appropriate rolling and compaction for the quality of asphalt is widely acknowledged and vital for improved process control. But what constitutes

  6. Crack repair of asphalt concrete with induction energy

    NARCIS (Netherlands)

    García, A.; Schlangen, E.; Ven, M. van de; Vliet, D. van

    2011-01-01

    It is well known that the healing rates of asphalt courses increase with the temperature. A new method, induction heating, is used in this paper to increase the lifetime of asphalt concrete pavements. Mastic will be first made electrically conductive by the addition of conductive fibers. Then it wil

  7. Crack repair of asphalt concrete with induction energy

    NARCIS (Netherlands)

    García, A.; Schlangen, E.; Van de Ven, M.; Van Vliet, D.

    It is well known that the healing rates of asphalt courses increase with the temperature. A new method, induction heating, is used in this paper to increase the lifetime of asphalt concrete pavements. Mastic will be first made electrically conductive by the addition of conductive fibers. Then it wil

  8. 7 CFR 2902.36 - Concrete and asphalt release fluids.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Concrete and asphalt release fluids. 2902.36 Section... PROCUREMENT Designated Items § 2902.36 Concrete and asphalt release fluids. (a) Definition. Products that are designed to provide a lubricating barrier between the composite surface materials (e.g., concrete...

  9. Characterization of Failure and Permanent Deformation Behaviour of Asphalt Concrete

    NARCIS (Netherlands)

    Wang, J.G.

    2015-01-01

    Asphalt concrete is a viscoelastic material consisting of aggregates, filler and bitumen. The response of asphalt concrete is highly dependent on temperature, loading rate and confining pressure. Permanent deformation is one of the most important distresses developing during the flexible pavement se

  10. Hot asphalt burns: a review of injuries and management options.

    Science.gov (United States)

    Bosse, George M; Wadia, Shernaz A; Padmanabhan, Pradeep

    2014-07-01

    Hot asphalt burns to human tissue can increase the likelihood of infection and potential conversion of partial thickness to full-thickness injuries. Successful intervention for hot asphalt burns requires immediate and effective cooling of the asphalt on the tissue followed by subsequent gradual removal of the cooled asphalt. A review of the literature reveals that multiple substances have been used to remove asphalt, including topical antibiotics, petroleum jelly, a commercial product known as De-Solv-It (ORANGE-SOL, Chandler, AZ), sunflower oil, baby oil, liquid paraffin, butter, mayonnaise, and moist-exposed burn ointment (MEBO). Although many of these products may be effective in the removal of asphalt, they may not be readily available in an emergency department setting. Topical antibiotics are readily available, are more commonly described in the medical literature, and would be expected to be effective in the removal of asphalt. We developed guidelines for on scene (first-aid) management and the initial care of such patients upon presentation to a health care facility. These guidelines emphasize the principles of early cooling, gradual removal of adherent asphalt using topical antibiotics, and avoidance of the use of topical agents, which are likely to result in tissue toxicity.

  11. Laboratory and Field Asphalt Fatigue Performance, Matching Theory with Practice

    NARCIS (Netherlands)

    Pramesti, F.P.

    2015-01-01

    This thesis investigates the relationship between predicted and observed fatigue life of asphalt. This study also investigates the positive effects of modifying bitumen with Retona, a bitumen modifier produced in Indonesia from natural asphalt rock sources, on pavement performance in terms of increa

  12. Fatigue Properties of Layered Double Hydroxides Modified Asphalt and Its Mixture

    Directory of Open Access Journals (Sweden)

    Xing Liu

    2014-01-01

    Full Text Available This study investigated the influence of layered double hydroxides (LDHs on the fatigue properties of asphalt mixture. In this paper, different aging levels (thin film oven test (TFOT and ultraviolet radiation aging (UV aging for short of bitumen modified with various mass ratios of the LDHs were investigated. The TFOT and UV aging process were used to simulate short-term field thermal-oxidative aging and long-term field light UV aging of bitumen, respectively. The influences of LDHs on the fatigue properties of LDHs were evaluated by dynamic shear rheometer (DSR and indirect tensile fatigue test. Results indicated that the introduction of LDHs could change the fatigue properties of bitumen under a stress control mode. The mixture with modified bitumen showed better fatigue resistance than the mixture with base bitumen. The results illustrated that the LDHs would be alternative modifiers used in the bitumen to improve the lifetime of asphalt pavements.

  13. Modeling of asphalt by means of discrete element method – an initial study

    DEFF Research Database (Denmark)

    Feng, Huan; Hededal, Ole; Stang, Henrik

    type of numerical simulation method which allows the finite displacement and rotation of discrete particles, making it an excellent tool to simulate the complex micro interaction between aggregate particles within an asphalt mixture, [3],[4] . In this research, PFC3D – a commercial DEM program...... of conducting time-consuming and lab-costly procedures. The use of numerical models, capable of reducing greatly the testing cost, has shown great potential in characterizing asphalt-aggregate mixtures for both material evaluation and structural design purposes, [1],[2]. Discrete element method (DEM) is one...... – will be applied. The work presented here will focus on the discrete element method as a tool for modelling composite materials, i.e. determination of a representative volume; boundary conditions; characterisation of the components mastic (binder + filler) and aggregates; and establishment of virtual test samples...

  14. Investigation of Using Waste Welded Tuff Material as Mineral Filler in Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Sebnem KARAHANCER

    2016-08-01

    Full Text Available In this paper, the welded tuff waste- known as koyke in Isparta region - was used in the hot mix asphalt (HMA as mineral filler for reduction of the moisture susceptibility of HMA. Optimum binder content was assessed with Marshall Design Method. First of all, welded tuff was substituted as filler with limestone filler in proportion of 50% and 100%. After that Marshall Stability test was performed on specimens. The results showed that the 50% substitution was more effective than the 100% substitution. Therefore, welded tuff was substituted with limestone filler in proportion of 25%, 50%, 65% and 75%. Next, Indirect Tensile Strength test was practiced on the fabricated specimens and the results were assessed. According to the Indirect Tensile Strength results, welded tuff with 65% was given higher strength than the limestone filler. As a result, it has come up that welded tuff can be used as mineral filler in the hot mix asphalt.

  15. Use of Recycling Building Demolition waste As Coarse Aggregate in Hot Mix Asphalt

    Directory of Open Access Journals (Sweden)

    Nabil I. Al- Sarrag* Hanaa Khaleel A Suham E. Saleh Al-Maliky

    2014-04-01

    Full Text Available At the recent years in Iraq, building demolition increase because of wars and the processes of destruction that lead to increase concrete waste, causing extreme pressure on the available land-filled sites that’s becomes a new challenge to local environment, in addition to south region from country poor from aggregate source.  So this study make as first evaluation to return use concrete aggregate for old and demolition building in concrete asphalt mix, the concrete aggregate obtained from building to live long more than 20 years after crash reinforcement concrete and sieving to get requirement granular particle to make locally asphalt mixture (Type IIIB depends on modified specification of State Commission of Roads and Bridges (2003 with percent (0,25,50,75,100% from weight of coarse aggregate.  Asphalt mixtures were tested by Marshall test, Indirect tensile strength test, and the loss of stability test.

  16. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Science.gov (United States)

    2010-07-01

    ... linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment... PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.40 Applicability; description of the linoleum and printed asphalt felt subcategory....

  17. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Science.gov (United States)

    2010-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to...

  18. 40 CFR 443.20 - Applicability; description of the asphalt concrete subcategory.

    Science.gov (United States)

    2010-07-01

    ... asphalt concrete subcategory. 443.20 Section 443.20 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Concrete Subcategory § 443.20 Applicability; description of the asphalt concrete subcategory. The provisions of this subpart are applicable to...

  19. 40 CFR Table 1 of Subpart Aaaaaaa... - Emission Limits for Asphalt Processing (Refining) Operations

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Emission Limits for Asphalt Processing... Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and Information... of Part 63—Emission Limits for Asphalt Processing (Refining) Operations For * * * You must meet...

  20. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Science.gov (United States)

    2010-07-01

    ... asphalt emulsion subcategory. 443.10 Section 443.10 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions of this subpart are applicable to...

  1. Intercalation of p-methycinnamic acid anion into Zn-Al layered double hydroxide to improve UV aging resistance of asphalt

    Directory of Open Access Journals (Sweden)

    Chao Peng

    2015-02-01

    Full Text Available A UV absorber, p-methycinnamic acid (PMCA, was intercalated into Zn-Al layered double hydroxide (LDH by calcination recovery. Fourier transform infrared spectroscopy showed that the PMCA anions completely replaced the CO32− anions in the interlayer galleries of Zn-Al-LDH containing PMCA anions (Zn-Al-PMCA-LDH. X-ray diffraction and transmission electron microscopy showed that the interlayer distance increased from 0.78 nm to 1.82 nm after the substitution of PMCA anions for CO32− anions. The similar diffraction angles of the CO32− anion-containing Zn-Al-LDH (Zn-Al-CO32−-LDH and the Zn-Al-CO32−-LDH/styrene–butadiene–styrene (SBS modified asphalt implied that the asphalt molecules do not enter into the LDH interlayer galleries to form separated-phase structures. The different diffraction angles of Zn-Al-PMCA-LDH and Zn-Al-PMCA-LDH/SBS modified asphalt indicated that the asphalt molecules penetrated into the LDH interlayer galleries to form an expanded-phase structure. UV-Vis absorbance analyses showed that Zn-Al-PMCA-LDH was better able to block UV light due to the synergistic effects of PMCA and Zn-Al-LDH. Conventional physical tests and atomic force microscopy images of the SBS modified asphalt, Zn-Al-CO32−-LDH/SBS modified asphalt and Zn-Al-PMCA-LDH/SBS modified asphalt before and after UV aging indicated that Zn-Al-PMCA-LDH improved the UV aging resistance of SBS modified asphalts.

  2. Thermal Conduction and Insulation Modification in Asphalt-Based Composites

    Institute of Scientific and Technical Information of China (English)

    Xiaofeng Zhou; Shengyue Wang; Chao Zhou

    2012-01-01

    The relationship between thermal conductivity and properties of mixing particles is required for quantitative study of heat transfer processes in asphalt-based materials. In this paper, we measured the e?ective ther- mal conductivity of asphalt-based materials with thermal conduction (graphite) and insulation (cenosphere) powders modification. By taking account of the particle shape, volume fraction, the thermal conductivity of filling particles and base asphalt, we present a new differential effective medium formula to predict the thermal conductivity modification in asphalt-based composite. Our theoretical predications are in good agreement with the experiment data. The new model can be applied for predicting the thermal properties of asphalt-based mixture, which is available for most of thermal modification in two-phase composites.

  3. Mechanical Properties of Asphalt Pavement Structure in Highway Tunnel

    Institute of Scientific and Technical Information of China (English)

    SHI Chun-xiang; GUO Zhong-yin

    2008-01-01

    A linear full 3D finite element method (FEM) was performed in order to present the key design parameters of highway tunnel asphalt pavement under double-wheel load on rectangular loaded area considering horizontal contact stress induced by the acceleration/deceleration of vehicles. The key design parameters are the maximum horizontal tensile stresses at the surface of the asphalt layer, the maximum horizontal tensile stresses at the bottom of the asphalt layer and the maximum vertical shear stresses at the surface of the as- phalt layer were calculated. The influencing factors such as double-wheel weight; asphalt layer thickness; base course stiffness modulus and thickness; and the contact conditions among the structure layers on these key design parameters were also examined separately to propose construction procedures of highway tunnel asphalt pavement.

  4. THE FATIGUE DURABILITY OF THE MODIFIED ASPHALT CONCRETE UNDER THE EFFECT OF INTENSIVE TRAFFIC LOADS

    Directory of Open Access Journals (Sweden)

    Yuri KALGIN

    2016-06-01

    Full Text Available The problem of prediction of the service life of asphalt concrete surface constructed with modified asphalt concrete application onto a traffic lane is examined. Asphalt concrete behaviour in road surface under the traffic loads was analysed. There were shown The results of experiments and their mathematical analysis of the assessment of standard and modified cold asphalt concrete fatigue life on road surface were shown. The service life of an asphalt concrete surface covered with standard and modified cold asphalt concrete is examined. The prediction has been received with an account of stress relaxation processes in asphalt concrete pavement and unevenness of traffic load application.

  5. Utilization of recycled asphalt concrete with warm mix asphalt and cost-benefit analysis.

    Science.gov (United States)

    Oner, Julide; Sengoz, Burak

    2015-01-01

    The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP) is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA) technology provides not only the option of recycling asphalt pavement at a lower temperature than the temperature maintained in hot mixtures but also encourages the utilization of RAP and therefore saves energy and money. This paper describes the feasibility of utilizing three different WMA additives (organic, chemical and water containing) at recommended contents with different percentages of RAP. The mechanical properties and cost-benefit analysis of WMA containing RAP have been performed and compared with WMA without RAP. The results indicated that, 30%, 10% and 20% can be accepted as an optimum RAP addition related to organic, chemical and water containing additives respectively and organic additive with 30% RAP content has an appreciable increase in tensile strength over the control mix. It was also concluded that the RAP with WMA technology is the ability to reduce final cost compared to HMA and WMA mixtures.

  6. Utilization of recycled asphalt concrete with warm mix asphalt and cost-benefit analysis.

    Directory of Open Access Journals (Sweden)

    Julide Oner

    Full Text Available The asphalt paving industries are faced with two major problems. These two important challenges are generated with an increase in demand for environmentally friendly paving mixtures and the problem of rapidly rising raw materials. Recycling of reclaimed asphalt pavement (RAP is a critical necessity to save precious aggregates and reduce the use of costly bitumen. Warm Mix Asphalt (WMA technology provides not only the option of recycling asphalt pavement at a lower temperature than the temperature maintained in hot mixtures but also encourages the utilization of RAP and therefore saves energy and money. This paper describes the feasibility of utilizing three different WMA additives (organic, chemical and water containing at recommended contents with different percentages of RAP. The mechanical properties and cost-benefit analysis of WMA containing RAP have been performed and compared with WMA without RAP. The results indicated that, 30%, 10% and 20% can be accepted as an optimum RAP addition related to organic, chemical and water containing additives respectively and organic additive with 30% RAP content has an appreciable increase in tensile strength over the control mix. It was also concluded that the RAP with WMA technology is the ability to reduce final cost compared to HMA and WMA mixtures.

  7. Surface Modification of Fire-retardant Asphalt with Silane Coupling Agent

    Institute of Scientific and Technical Information of China (English)

    CHEN Huiqiang; TANG Boming

    2012-01-01

    The theory and approach of the surface modified of asphalt fire-retardant with silane coupling agent were introduced,The optimum silane dosage was determined,and the structure and properties of the asphalt fire-retardant before and after the surface modification were characterized by infrared spectrum and thermo gravimetric analysis.The dispersion effect of asphalt fire-retardant was studied.The influence of the surface modification on the hydrophilicity and lipophilicity of the asphalt fire-retardant was analyzed.The experimental results showed that there were physical and chemical interactions between the silane coupling agent and the asphalt fire-retardant,which reduced the surface polarity of the asphalt fire retardant.The optimum silane coupling agent dosage was 0.95% of the asphalt fire retardant.The surface modification improved the thermal stability,dispersibility and lipophilicity of the asphalt fire retardant,which enhanced the compatibility between asphalt fire retardant and asphalt.

  8. Rutting analysis of 100 mm diameter polypropylene modified asphalt specimens using gyratory and Marshall compactors

    Directory of Open Access Journals (Sweden)

    Serkan Tapkın

    2013-04-01

    Full Text Available Compaction technique used in Marshall design does not model the process of actual rolling procedures on site exactly. Carrying out laboratory compaction of dense bituminous mixtures with Superpave gyratory compactors is a more realistic way of simulating actual compaction. In this study, mechanical differences of reference and polypropylene modified asphalt mixtures were compared using Superpave gyratory and Marshall compaction methods by carrying out repeated creep tests utilising universal testing machine. In addition, there is no standard Superpave design procedure for 100 mm diameter samples till date. The other purpose of this study is to propose new standards for the compaction and testing procedures of these 100 mm specimens. Indeed, extensive studies have shown that the design gyration number should be 40 for reference and 33 for polypropylene modified specimens under medium traffic conditions for the similar and specific type of aggregate sources, bitumen, aggregate gradation, mix proportioning, modification technique and laboratory conditions. Moreover, it was shown that, the asphalt samples produced by Superpave gyratory compactor were much resistant to destructive rutting effects than the asphalt specimens prepared by Marshall design.

  9. Evaluation of Warm Mix Asphalt Technologies and Recycled Asphalt Pavements in Truckee Meadows, Nevada

    Science.gov (United States)

    Diaz Montecino, Cristian

    This study evaluated the properties and laboratory-performance of Hot Mix Asphalt (HMA) and Warm Mix Asphalt (WMA) mixtures with different levels of Recycled Asphalt Pavements (RAP) content: none for control mixtures, around 15% by dry weight of aggregates, and more than 30% by dry weight of aggregates. The rheological properties were evaluated for virgin and recovered RAP asphalt binders. The target amount of RAP in the mixtures was determined by using Blending Charts and Mortar Experiments. The mixtures are design through the guidelines established in Marshall Mix Design Method considering additional modifications for RAP and WMA from Superpave Mix Design. The mixtures are evaluated for their resistance to moisture damage by means of measuring the Dynamic Modulus |E*| after three freeze/thaw cycles and the indirect tensile strength after one and three freeze/thaw cycles. The resistance of the mixtures to permanent deformation was also evaluated by using the Asphalt Mixture Performance Tester (AMPT) to measure the flow number (FN). For this study, it was determined that the resistance to moisture damage decreases as the number of freeze/thaw cycles increases for most of the evaluated mixtures. Mixtures exhibited an increase in dynamic modulus as the RAP percentage increased. A decrease in the resistance to moisture damage was detected with the increase in RAP content for most of the mixtures. HMA mixtures exhibited a better performance in rutting than the WMA mixtures. An increase in rutting resistance was observed with the increase in RAP percentage for HMA mixtures whereas an inconsistent trend was observed for WMA mixtures. Further study is needed to validate the use of the high percentage of RAP in Washoe County.

  10. Relationship among asphalt component,viscosity and adhesion in triangular coordinate system%三角形坐标系下沥青组分与粘度、粘附性关系

    Institute of Scientific and Technical Information of China (English)

    傅珍; 延西利; 蔡婷; 马峰; 汪林兵

    2014-01-01

    为研究沥青的组分和组分构成关系对沥青技术性质的影响,选用13种道路石油沥青和2种集料,采用四组分、表观粘度与粘附性试验研究了沥青组分与粘度、粘附性之间的关系。提出了三角形坐标系下的沥青四组分试验结果表征方法,采用沥青四组分数据绘制沥青特征三角形,利用惯性矩反映沥青的组分构成特征,分析了沥青四组分数据构成的三棱锥几何特性与粘度、粘附性的联系。试验结果表明:除沥青的组成成分之外,沥青组成成分的结构差异也会影响其粘度及集料粘附性;对于不同品牌而相同标号的沥青,在三角形坐标系下,沥青组分特征三角形的惯性矩越大,与集料粘附性越好。%In order to assess the influences of asphalt component and composition on asphalt technical properties,thirteen types of pavement petroleum asphalts and two kinds of typical aggregates were selected.The relationship among asphalt component,viscosity and adhesion was investigated by using tests of four-component, apparent viscosity and adhesion. The characterization method of asphalt four-component test result by using triangular coordinate system was put forward.The asphalt characteristic triangle was drawn with four-component data.The characteristic of asphalt composition was represented by inertia moment.The asphalt pyramid was drawn based on asphalt four-component data and the relationship among its geometry characteristics,viscosity and adhesion was analyzed.Analysis result indicates that except asphalt components,its composition differences also have influences on asphalt viscosity and aggregate adhesion.For the asphalts with same penetration grade and different brands, triangular coordinate analysis result shows the aggregate adhesion increases with the increase of the inertia moment of asphalt four-component characteristic triangle.6 tabs,6 figs,18 refs.

  11. Shear resistance properties of TPS modified bitumen binders and asphalt mixtures

    Institute of Scientific and Technical Information of China (English)

    曹庭维; 吴少鹏; 刘聪慧; 张涛

    2008-01-01

    Shear resistance properties of the virgin bitumen and modified bitumen binders with Tafpack Super(TPS) modifier and SBS modified bitumen were discussed.Dynamic shear rheometer(DSR) was used to measure the laboratory creep data for these binders over a wide range of constant shear stresses at 20 ℃ to characterize the shear creep behaviors of all kinds of asphalt binders,and the rutting test system was used to investigate the permanent deformation of porous asphalt mixtures using the above bitumen binders for a fixed compressive stress.The shear strain rate and shear creep modulus were used to characterize the shear creep behavior of the TPS modified bitumen,and the rutting test results were used to show the consistency of porous asphalt mixtures with the bitumen binders.Results indicate that a distinction of shear creep strain can be made among different contents of TPS modified bitumen at the same stress level,where the shear creep strain-time response curve of the SBS modified bitumen binder is between the curves of the 8% TPS and 12% TPS modified bitumen binders.The shear strain rate and the shear creep modulus of the TPS modified bitumen binders are obtained to compare with those of the SBS modified bitumen binder which results in the same trend as the shear creep strain-time response curve.Permanent deformation results of all the porous asphalt mixtures from the rutting test show reasonable agreement with the findings of the shear strain rates and shear creep modulus over the range of shear stress levels.

  12. 间断级配橡胶沥青混合料设计与性能分析%Design of Interrupted Grade Rubber Asphalt Mixture and Analysis of Performance

    Institute of Scientific and Technical Information of China (English)

    许勇; 张强; 王传峰

    2009-01-01

    橡胶沥青混合料是指采用橡胶沥青作为结合料与集料加热拌和而得到的一种沥青混合料.该文首先阐述了橡胶沥青混合料设计的主要问题是选择何种级配来适应粘度大且包含着大量橡胶颗粒的橡胶沥青结合料.接着分析了各种级配对橡胶沥青的适应性,并采用马歇尔试验方法完成了间断级配橡胶沥青混合料的设计.最后对其路用性能进行了测试分析.%The rubber asphalt mixture is an asphalt mixture by taking the rubber asphalt as the bonding material to be heated and mixed with the aggregates. The article firstly sets forth the main problem in the design of rubber asphalt mixture, and that is to select which grade for suiting the high viscosity and mass rubber grain of rubber asphalt bonding material. The article analyzes the adaptability of various grades on the rubber asphalt, and uses Masher test method to complete the design of interrupted grade rubber asphalt mixture, and finally carries out the test analysis of its road performance.

  13. Research on Performance of Asphalt Modified by Polyethylene Made from Recycled Plastics%废旧塑料合成MPE颗粒对沥青改性效果的试验研究

    Institute of Scientific and Technical Information of China (English)

    王家主

    2011-01-01

    Granular modified polyethylene made from recycled plastics and tackifier can be added to asphalt mix plant to modify asphalt, which avoids the process of modifying asphalt in the factory. Two virgin asphalts, with their four components content tested, are chosen to study the MPE modified asphalt. Asphalts with different quantities of MPE are prepared by high speed shearing machine. And asphalt performance of every sample is tested, which varied with different MPE content, meanwhile, curves of performance versus MPE content are drawn. Last, all the test results and analysis indicate that MPE can obviously improve asphalt performances such as high temperature performance, aging resistance and anti-stripping. However, there is an optimal MPE content which is 6% of asphalt mass.%采用废旧塑料和增黏剂合成的MPE颗粒,可在道路沥青混合料拌和时直接投入,起到对道路沥青改性的作用,省去了在加工厂制备生产改性沥青的过程.为研究MPE对沥青的改性作用,选取两种基质沥青,测定其四组分含量,通过高速剪切设备制备不同MPE掺量的改性沥青,分别对其进行沥青性能的检测,绘制各项沥青性能随MPE掺量的变化曲线.试验结果表明,MPE对沥青的高温、老化和水稳定性能具有明显的改善作用,同时MPE存在一个最佳掺量,约为沥青质量的6%.

  14. Microbial Life in a Liquid Asphalt Desert

    CERN Document Server

    Schulze-Makuch, Dirk; Antonio, Marina Resendes de Sousa; Ali, Denzil; Hosein, Riad; Song, Young C; Yang, Jinshu; Zaikova, Elena; Beckles, Denise M; Guinan, Edward; Lehto, Harry J; Hallam, Steven J

    2010-01-01

    An active microbiota, reaching up to 10 E+7 cells/g, was found to inhabit a naturally occurring asphalt lake characterized by low water activity and elevated temperature. Geochemical and molecular taxonomic approaches revealed novel and deeply branching microbial assemblages mediating anaerobic hydrocarbon degradation, metal respiration and C1 utilization pathways. These results open a window into the origin and adaptive evolution of microbial life within recalcitrant hydrocarbon matrices, and establish the site as a useful analog for the liquid hydrocarbon environments on Saturn's moon Titan.

  15. Discrete Element Modeling of Asphalt Concrete Cracking Using a User-defined Tlree-dimensional Micromechanical Approach

    Institute of Scientific and Technical Information of China (English)

    CHEN Jun; PAN Tongyan; HUANG Xiaoming

    2011-01-01

    We established a user-defined micromechanical model using discrete element method (DEM) to investigate the cracking behavior of asphalt concrete (AC).Using the “Fish” language provided in the particle flow code in 3-Demensions (PFC3D),the air voids and mastics in asphalt concrete were realistically built as two distinct phases.With the irregular shape of individual aggregate particles modeled using a clump of spheres of different sizes,the three-dimensional (3D) discrete element model was able to account for aggregate gradation and fraction.Laboratory uniaxial complex modulus test and indirect tensile strength test were performed to obtain input material parameters for the numerical simulation.A set of the indirect tensile test were simulated to study the cracking behavior of AC at two levels of temperature,i e,-10 ℃ and 15 ℃.The predicted results of the numerical simulation were compared with laboratory experimental measurements.Results show that the 3D DEM model is able to predict accurately the fracture pattern of different asphalt mixtures.Based on the DEM model,the effects of air void content and aggregate volumetric fraction on the cracking behavior of asphalt concrete were evaluated.

  16. The Comparison of Engineering Properties Between Single and Double Layer Porous Asphalt made of Packing Gradation

    Directory of Open Access Journals (Sweden)

    Hardiman M. Y

    2008-01-01

    Full Text Available is paper presents the comparison of engineering properties between single and double layer porous asphalt (SLPA and DLPA made of packing gradation. Three nominal maximum aggregate sizes (NMAS were tested each made up of 10, 14, and 20 mm for SLPA. While for the DLPA with 30, 20, and 15 mm top layer are made of 10 and 14 mm NMAS, with a base layer of 20 mm NMAS. Total thickness of all mixes is 70 mm. Binders used are 60/70 penetration base bitumen and polymer binder styrene-butadiene-styrene (SBS. The result shows that the properties of SLPA mix namely permeability and resistance to abrasion loss decreases when the NMAS in SLPA decreases. The abrasion loss of DLPA mixes increases when the porous asphalt top layer thickness decreases, while drainage time value decreases. However, SLPA with 20 mm NMAS exhibits higher abrasion loss compared to all DLPA mixes.

  17. Effect of Carbon Nanofiber on Mechanical Behavior of Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Saeed Ghaffarpour Jahromi

    2015-09-01

    Full Text Available Uses of fibers to improve material properties have a scientific background in recent years in civil engineering. Use of Nanofiber reinforcement of materials refers to incorporating materials with desired properties within some other materials lacking those properties. Use of fibers for improvement is not a new phenomenon as the technique of fiber-reinforced bitumen began as early as 1950, but using nanofiber is a new idea. In this research the mechanical properties of asphalt mixture that have been modified with carbon nanofiber were investigated using mechanical tests, which can improve the performance of flexible pavements. To evaluate the effect of nanofiber contents on bituminous mixtures, laboratory investigations were carried out on the samples with and without nanofibers. During the course of this study, various tests were undertaken applying the Marshall test, indirect tensile test, resistance to fatigue cracking by using repeated load indirect tensile test and creep test. Carbon nanofiber exhibited consistency in results and it was observed that the addition of nanofiber can change the properties of bituminous mixtures, increase its stability and decrease the flow value. Results indicate that nanofiber have the potential to resist structural distress in the pavement and thus improve fatigue by increasing resistance to cracks or permanent deformation, when growing traffic loads. On the whole, the results show that the addition of carbon nanofiber will improve some of the mechanical properties such as fatigue and deformation in the flexible pavement.

  18. A Study on the Rheological Properties of Recycled Rubber-Modified Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Murat Karacasu

    2015-01-01

    Full Text Available Using waste rubber in asphalt mixes has become a common practice in road construction. This paper presents the results of a study on the rheological characteristics of rubber-modified asphalt (RMA concrete under static and dynamic loading conditions. A number of static and dynamic creep tests were conducted on RMA mix specimens with different rubber sizes and contents, and a series of resonant column tests were conducted to evaluate the shear modulus and damping values. To simulate the stress-strain response of traffic-induced loading, the measurements were taken for different confining pressures and strain levels. The results of the study indicated that rubber modification increases stiffness and damping ratio, making it a very attractive material for use in road construction. However the grain size of the rubber is very important. Although RMA may cost up to 100% more than regular asphalt, the advantages it brings, such as an increased service life of the road and proper waste utilization contributing to a more sustainable infrastructure, may justify the added cost.

  19. Stripping in hot mix asphalt produced by aggregates from construction and demolition waste.

    Science.gov (United States)

    Pérez, I; Pasandín, A R; Gallego, J

    2012-01-01

    This paper analyses the effect of water on the durability of hot asphalt mixtures made with recycled aggregates from construction and demolition debris. Indirect tensile stress tests were carried out to evaluate stripping behaviour. The mixtures tested were fabricated with 0, 20, 40 and 60% recycled aggregates. Two types of natural aggregates were used: schist and calcite dolomite. An increase in the percentage of recycled aggregates was found to produce a decrease in the tensile stress ratio of the hot asphalt mixtures. To study this phenomenon, two and three factor analyses of variance (ANOVA) were performed with indirect tensile stress being used as the dependent variable. The factors studied were the percentage of recycled aggregates (0, 20, 40 and 60%), the moisture state (dry, wet) and the type of natural aggregate (schist, calcite). On the basis of the ANOVA results, it was found that the most important factor affecting resistance was the moisture state (dry, wet) of the specimens. The percentage of recycled aggregate also affected indirect tensile stress, especially in the dry state. The type of natural aggregate did not have a significant effect on indirect tensile stress. The hot asphalt mixture specimens made with different percentages of recycled aggregates from construction and demolition debris and of natural quarry aggregates showed poor stripping behaviour. This stripping behaviour can be related to both the poor adhesion of the recycled aggregates and the high absorption of the mortar of cement adhered to them.

  20. Assessment of the aging level of rejuvenated hot mixed asphalt concrete pavements

    Science.gov (United States)

    McGovern, Megan; Buttlar, William G.; Reis, Henrique

    2016-04-01

    The efficacy of asphalt rejuvenator on restoring the properties of oxidatively aged asphalt was tested via a non-collinear ultrasonic subsurface wave mixing technique modified for field use. Longitudinal transducers were mounted on angle wedges to generate subsurface dilatational waves to allow for pavement evaluation when there is only access to one side. Because in the field the asphalt concrete (AC) pavement properties (i.e., ultrasonic velocities and attenuations) are unknown, a pre-determined fixed incident angle (based on the AC mixture type) was used, which allows for practical implementation in the field. Oxidative aged AC specimens were coated with rejuvenator (10% by weight of the binder) and left to dwell for varying amounts of time. Once the dwell time reached the desired amount, the specimen was immediately ultrasonically tested. The frequency ratio, f2/f1, at which the interaction took place and the normalized nonlinear wave generation parameter, β/β0, were recorded and compared against a reference plot. It was observed that the rejuvenator had the effect of restoring the nonlinear properties to those corresponding to a virgin sample after a sufficient amount of dwell time. The ability of the rejuvenator to fully penetrate and act on the binder was observed to be dependent on the porosity and aggregate structure, and thus varied for each specimen. As a result, some portions of the binder were restored to a greater extent than others. This non-uniform nature was captured via the nonlinear ultrasonic technique.

  1. A study on the rheological properties of recycled rubber-modified asphalt mixtures.

    Science.gov (United States)

    Karacasu, Murat; Okur, Volkan; Er, Arzu

    2015-01-01

    Using waste rubber in asphalt mixes has become a common practice in road construction. This paper presents the results of a study on the rheological characteristics of rubber-modified asphalt (RMA) concrete under static and dynamic loading conditions. A number of static and dynamic creep tests were conducted on RMA mix specimens with different rubber sizes and contents, and a series of resonant column tests were conducted to evaluate the shear modulus and damping values. To simulate the stress-strain response of traffic-induced loading, the measurements were taken for different confining pressures and strain levels. The results of the study indicated that rubber modification increases stiffness and damping ratio, making it a very attractive material for use in road construction. However the grain size of the rubber is very important. Although RMA may cost up to 100% more than regular asphalt, the advantages it brings, such as an increased service life of the road and proper waste utilization contributing to a more sustainable infrastructure, may justify the added cost.

  2. Effects of Asphalt Mix Design Properties on Pavement Performance: A Mechanistic Approach

    Directory of Open Access Journals (Sweden)

    Ahmad M. Abu Abdo

    2016-01-01

    Full Text Available The main objective of this study was to investigate the effects of hot mix asphalt material properties on the performance of flexible pavements via mechanistic approach. 3D Move Analysis software was utilized to determine rutting and cracking distresses in an asphalt concrete (AC layer. Fourteen different Superpave mixes were evaluated by utilizing results of the Dynamic Modulus (|E⁎| Test and the Dynamic Shear Modulus (|G⁎| Test. Results showed that with the increase of binder content, the tendency of rutting in AC layer increased. However, with the increase of binder content, the cracking of AC layer lessened. Furthermore, when different binder grades were evaluated, results showed that with the increase of the upper binder grade number, rutting decreased, and with the increase of the lower binder grade number, rutting increased. Furthermore, analysis showed that with the increase of the lower binder grade number, higher percent of bottom up cracks would result. As a result of the analysis, binder grade should not be solely considered for cracking in AC layer; binder content and aggregate structure play a big role. Finally, results illustrated that the mechanistic approach is a better tool to determine the performance of asphalt pavement than commonly used methods.

  3. Evaluation of Hydrated Lime Filler in Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Mohammed Abbas Hasan Al-Jumaily

    2008-01-01

    Full Text Available Mineral filler is one of important materials and affecting on properties and quality of asphalt mixtures .There are different types of mineral filler depended on cost and quality , the matter encourages us to achieve this study to evaluate hydrated lime filler effects on properties of asphalt mixes related with strength and durability. Conventional asphaltic concrete mixtures with Portland cement and soft sandstone fillers and mixtures modified with hydrated lime were evaluated for their fundamental engineering properties as defined by Marshall properties , index of retained strength , indirect tensile strength , permanent deformation characteristics , and fatigue resistance .A typical dense graded mixture employed in construction of surface course pavement in Iraq in accordance with SCRB specifications was used .The materials used in this study included mineral aggregate materials (coarse and fine sizes were originally obtained from Najaf Sea quarries and two grades of asphalt cements produced from Daurah refinery which are D47 and D66 . The physical properties , stiffness modulus and chemical composition are evaluated for the recovered asphalt cement from prepared asphalt mixes containing various filler types .The paper results indicated that the addition of hydrated lime as mineral filler improved the permanent deformation characteristics and fatigue life and the use of hydrated lime will decrease the moisture susceptibility of the asphalt mixtures.

  4. Study on the hardening mechanism of cement asphalt binder

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The hydration and hardening mechanism of cement asphalt binder(CAB) was studied.The early hydration process,hydration products and paste microstructure of CAB made by Portland cement and anionic asphalt emulsion were investigated by calorimetry,X-ray diffraction,and environmental scanning electron microscopy.The early hydration process of CAB can be characterized as 5 stages similar to those of Portland cement.There is no chemical reaction detected between cement and asphalt,hence no new hydration products other than those of Portland cement are produced.The hardening of CAB begins with the hydration of cement.When the hydration of cement comes into the acceleration period and its exothermic rate comes to the maximum,the coalescence of asphalt particles in asphalt emulsion is triggered.In the hardened system of CAB,it was found that the hydration products of cement form the skeleton and are covered by the continuous asphalt film.They formed an interpenetrating network system.The emulsifiers in the asphalt emulsion may retard the hydration process of cement.

  5. Comparison of renewable oil, recycled oil, and commercial rejuvenating agent derived from crude oil in paving asphalt modification[Includes the CSCE forum on professional practice and career development : 1. international engineering mechanics and materials specialty conference : 1. international/3. coastal, estuarine and offshore engineering specialty conference : 2. international/8. construction specialty conference

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, C.; Ho, S.; Zanzotto, L. [Calgary Univ., AB (Canada). Schulich School of Engineering

    2009-07-01

    The asphalt industry relies heavily on crude oil. In response to increasing oil prices, there have been efforts to save money on asphalt by taking harder asphalts, such as recycled asphalt pavement (RAP), and softening them with rejuvenating agents. For asphalt that is to be used in cold climates, softer asphalts are preferred because they will perform better under extreme cold conditions without cracking. This study compared the performance, economic benefits, and environmental benefits of renewable materials, recycled oil and a commercially used rejuvenating agent derived from crude oil. Different oily materials including margarine, Cyclogen L (a crude oil-derived material), a vegetable wax, and recycled cooking oil were used to modify paving asphalt. Their effectiveness at improving the superpave low-temperature performance grade was compared. The samples were all tested using the 2008 AASHTO M320 procedures. The high temperature grades were determined using the dynamic shear rheometer test, and the low-temperature grades were determined using the bending beam rheometer test. The 3 varieties of margarine that were tested were able to improve the low-temperature grade, but they caused a greater depreciation of the high-temperature performance grade than the other materials, and were much more expensive. The best candidate for an effective, economic asphalt softening agent was found to be the recycled cooking oil. It out-performed the Cyclogen L oil in terms of improving the low- temperature performance grade, and was less expensive. 12 refs., 4 tabs., 6 figs.

  6. 新型反应性改性沥青改性剂技术性能研究%Study on Properties of Reactive Asphalt Modifiers

    Institute of Scientific and Technical Information of China (English)

    曹晓娟

    2015-01-01

    对不同种类改性沥青混合料进行了动态模量试验、小梁弯曲疲劳试验、动态蠕变拉伸试验和无侧限拉伸试验,通过对这四种试验结果进行分析研究,对比了不同种类改性沥青混合料的技术性能,评价了 RET改性剂对沥青混合料路用性能的改善效果。%Different types of modified asphalt mixtures were analyzed by dynamic modulus test, beam bending fatigue test, dynamic creep tests and double-edge-notched tension test, technical properties of different types of modified asphalt mixtures were compared, improvement effect of RET modifier for asphalt pavement performance was evaluated.

  7. Characterization of asphalt materials containing bio oil from michigan wood

    Science.gov (United States)

    Mills-Beale, Julian

    The objective of this research is to develop sustainable wood-blend bioasphalt and characterize the atomic, molecular and bulk-scale behavior necessary to produce advanced asphalt paving mixtures. Bioasphalt was manufactured from Aspen, Basswood, Red Maple, Balsam, Maple, Pine, Beech and Magnolia wood via a 25 KWt fast-pyrolysis plant at 500 °C and refined into two distinct end forms - non-treated (5.54% moisture) and treated bioasphalt (1% moisture). Michigan petroleum-based asphalt, Performance Grade (PG) 58-28 was modified with 2, 5 and 10% of the bioasphalt by weight of base asphalt and characterized with the gas chromatography-mass spectroscopy (GC-MS), Fourier Transform Infra-red (FTIR) spectroscopy and the automated flocculation titrimetry techniques. The GC-MS method was used to characterize the Carbon-Hydrogen-Nitrogen (CHN) elemental ratio whiles the FTIR and the AFT were used to characterize the oxidative aging performance and the solubility parameters, respectively. For rheological characterization, the rotational viscosity, dynamic shear modulus and flexural bending methods are used in evaluating the low, intermediate and high temperature performance of the bio-modified asphalt materials. 54 5E3 (maximum of 3 million expected equivalent standard axle traffic loads) asphalt paving mixes were then prepared and characterized to investigate their laboratory permanent deformation, dynamic mix stiffness, moisture susceptibility, workability and constructability performance. From the research investigations, it was concluded that: 1) levo, 2, 6 dimethoxyphenol, 2 methoxy 4 vinylphenol, 2 methyl 1-2 cyclopentandione and 4-allyl-2, 6 dimetoxyphenol are the dominant chemical functional groups; 2) bioasphalt increases the viscosity and dynamic shear modulus of traditional asphalt binders; 3) Bio-modified petroleum asphalt can provide low-temperature cracking resistance benefits at -18 °C but is susceptible to cracking at -24 °C; 3) Carbonyl and sulphoxide

  8. Low permeability asphalt concrete gamma ray shielding properties.

    Science.gov (United States)

    Binney, S E; Sykes, K L

    1997-01-01

    Energy-dependent gamma ray shielding properties were measured as a function of gamma ray energy for a low permeability asphalt concrete that is used as a cap to prevent water infiltration into radioactive waste sites. Experimental data were compared to ISO-PC point kernel shielding calculations. Calculated dose equivalent rates compared well with experimental values, especially considering the poor detector resolution involved. The shielding properties of the asphalt concrete closely resembled those of aluminum. The results presented can be used to determine the asphalt concrete thickness required to reduce dose equivalent rates from several gamma ray emitting radionuclides.

  9. 添加磷酸对沥青混凝土性能影响%Effect of Phosphoric Acid on Performance of Asphalt Concrete

    Institute of Scientific and Technical Information of China (English)

    董苋伯; 吴进良

    2012-01-01

    以AC-20为基底沥青,磷酸作为改质剂,研究添加磷酸对沥青胶浆性质的影响,并以磷酸改质沥青作为马歇尔试体,研究添加磷酸对沥青混凝土性能的影响。经过试验,添加磷酸确实有效增加沥青胶浆的劲度,也会加速沥青胶浆的老化;增加混凝土承载力、抵抗车辙变形能力、抗张强度和耐磨损能力。添加磷酸也会降低沥青混凝土抗水侵害能力,磷酸的添加量越多,沥青混凝土水害的情形越严重,根据试验结果,建议磷酸可以添加到2%。%This study used AC-20 as the basis asphalt and phosphoric acid was used as a modifier to evaluate effect of phosphoric acid on the properties of asphalt, marshall samples were fabricated with phosphoric acid modified asphalt to study effect of phosphoric acid on the performance of asphalt concerte. According to result of tests, adding the phosphoric acid would increase asphalt stiffness, but would accelerate the as- phalt aging. Because adding the phosphoric acid would increase asphalt stiffness, the resistance of rutting, tensile strength and the resistance of wearing of asphalt concrete were all improve. But the resistance to moisture damage was reduced. Results of the tests, showed that phosphoric acid could be added about 2%.

  10. Influence of Rubber Asphalt on High Temperature Stability of Mixture%橡胶沥青对混合料高温稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    安东朝; 张国彬

    2014-01-01

    通过室内标准车辙试验和全厚式车辙试验,采用单因素对比分析的方法,研究了橡胶沥青对沥青路面高温稳定性的影响。试验结果表明,橡胶沥青与基质沥青比较,对路面的高温抗车辙性能有更大的改善,而且不同橡胶粉掺量也会影响到橡胶沥青的性能。通过全厚式车辙试验,将路面结构与温度梯度等因素考虑进来,使得车辙试验更符合实际路面情况,其试验结果表明各结构层对路面的影响区别较大,双层同时掺入橡胶沥青也比只改善路面高温稳定性更为有效。%Through the indoor standard rutting test and full depth rutting test,the article researches that the rubber asphalt has the influence on high temperature stability of asphalt pavement by the method of univariate comparative analysis. The result shows that the rubber asphalt has greater improvement on pavement rutting resistance in high temperature compared with general asphalt and different proportion of rubber powder also effects the performance of rubber asphalt. Through the full depth rutting test,consid-ered of the factors including pavement structure and temperature gradient,the rutting test becomes more conformed with the actual road conditions. The test results show that each structural layer has different in-fluence on asphalt pavement, and the double asphalt layers mixed rubber asphalt is more effective to im-prove the high temperature stability of highway compared with the single layer mixed rubber asphalt.

  11. Preparation of Nano-modified Asphalt and Its Road Performance Evaluation%纳米改性沥青制备和路用性能研究

    Institute of Scientific and Technical Information of China (English)

    孙璐; 朱浩然; 辛宪涛; 王鸿遥; 顾文钧

    2013-01-01

    In order to improve the road performance of base asphalt, nano-Ⅰ was used as a modifier, and A, B and C were separately used as dispersants to prepare nano-modified asphalt and the road performance of those asphalts was evaluated. In addition, nano-Ⅰ and SBS compound modified asphalt was also prepared to study the effect of nano- I on the polymer modified asphalt. Among all types of nano-Ⅰ modified asphalt, the cases with outstanding performance were selected to conduct DSR and BBR tests to further evaluate their road performance. The results show that nano-Ⅰ can significantly improve the high temperature performance of asphalt; surface modification of nano-Ⅰ particles has a significant effect on asphalt performance, so it is necessary to develop a surface modification technology suitable for asphalt modification to realize the nano-effect completely; nano-Ⅰ can further improve both the high temperature and low temperature performance of SBS modified asphalt.%为提高基质沥青的路用性能,采用纳米Ⅰ作为改性剂,并选用A,B和C作为分散剂,制备了纳米改性沥青并进行路用性能评价;同时将纳米工与SBS复合进行沥青改性,以考察纳米Ⅰ对聚合物改性沥青性能的影响.对其中的优选改性方案,进行DSR和BBR试验,进一步评价其路用性能.结果表明:纳米Ⅰ可以明显改善沥青的性能,使沥青的高温性能得以显著提高;纳米粒子的表面改性对沥青的性能有显著影响,有必要开发适用于沥青的纳米粒子表面改性方案,以充分发挥粒子的纳米效应;纳米Ⅰ对SBS改性沥青的影响表现为高、低温路用性能的全面提高.

  12. Crack Initiation Assessment of Wearing Course Asphalt Mixtures Using Aggregate Gradation Characteristic

    Directory of Open Access Journals (Sweden)

    Dr. Iman Haryanto

    2007-05-01

    Full Text Available At normal service temperatures, wearing course asphalt mixtures may have ductile cracking. Aggregate gradation characteristic is important to avoid the premature cracking. The present study discusses a relationship between the characteristic of aggregate gradation and crack resistance of wearing course mixtures. Asphalt mixture specimens were prepared using different types of aggregate gradation. The Bailey method was employed in order to recognize the characteristic of aggregate gradations. Notched semi circular bending test was conducted to obtain the critical J integral (Jc. The coarse aggregate (CA ratio and the fine graded fine aggregate coarse (FG FAc ratio defined by the Bailey method were introduced to recognize the effect of aggregate gradation type on Jc. The result was decreasing the Jc value with increasing the CA ratio and FG FAc ratio. Satisfying the current Bailey criterion on the CA ratio for stone mastic asphalt mixtures and setting FG FAc of fine graded HMA mixtures near 0.4 seem useful in order to obtain HMA mixtures with a high Jc. The present study also discusses spherical aggregates assembly models as an aid to illustrate development of the aggregates interlocking, which influences to the cracking.

  13. Experimental evaluation of high performance base course and road base asphalt concrete with electric arc furnace steel slags.

    Science.gov (United States)

    Pasetto, Marco; Baldo, Nicola

    2010-09-15

    The paper presents the results of a laboratory study aimed at verifying the use of two types of electric arc furnace (EAF) steel slags as substitutes for natural aggregates, in the composition of base course and road base asphalt concrete (BBAC) for flexible pavements. The trial was composed of a preliminary study of the chemical, physical, mechanical and leaching properties of the EAF steel slags, followed by the mix design and performance characterization of the bituminous mixes, through gyratory compaction tests, permanent deformation tests, stiffness modulus tests at various temperatures, fatigue tests and indirect tensile strength tests. All the mixtures with EAF slags presented better mechanical characteristics than those of the corresponding asphalts with natural aggregate and satisfied the requisites for acceptance in the Italian road sector technical standards, thus resulting as suitable for use in road construction.

  14. 信息动态%A Research on the Pavement Performance of Warm Mix Buton Mastic Asphalt

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Compositing modified asphalt mixture is a kind of asphalt mixture which uses Buton Mastic Asphalt(BMA) and warm modifier compound modification. It is proved that the composite modified asphalt mixture technology can greatly reduce the mixing temperature, save energy and protect the environment, and can guarantee good road performance. Employing Buton Mastic Asphalt as modifier can obviously increase the high temperature stability of asphalt mixture, with little impact on low temperature performance.

  15. Storm Water General Permit 3 for Rock and Asphalt

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — General permit #3 for storm water discharges associated with industrial activity for Asphalt Plants, Concrete Batch Plants, Rock Crushing Plants and Construction...

  16. Experimental evaluation of using stainless steel slag to produce mechanomutable asphalt mortars for their use in smart materials

    Science.gov (United States)

    Moreno-Navarro, F.; Iglesias, G. R.; Rubio-Gámez, M. C.

    2016-11-01

    Mechanomutable asphalt binders are a new generation of smart materials, which are able to change their mechanical response to the load conditions suffered during their service life. These binders are composed of a bituminous matrix and iron micro-particles that can be activated with an external magnetic field, which induces mechanical changes in the system. However, these particles are expensive and they considerably increase the cost of these materials, reducing their competiveness. Thus, the aim of this work is to study the viability to produce more sustainable and low-cost mechanomutable asphalt mortars using stainless steel slag (SSS). This by-product is obtained from the production of stainless steel and contains a significant quantity of iron that could be used to activate the response of these materials. Different sizes and concentrations of SSS were used to manufacture mechanomutable asphalt mortars, and their mechanical behavior was then examined using several rheological tests. The results show that it is possible to achieve changes in the rheological response of these smart asphalt materials, thereby obtaining mechanomutable mortars from the stainless steel by-products. The efficiency of the slag also appears to be more dependent on its iron content than on its concentration or particle size.

  17. POE弹性体改性沥青的结构与性能%Structure and properties of POE modified asphalt

    Institute of Scientific and Technical Information of China (English)

    谢玉阁; 姚鸿儒; 黄健

    2013-01-01

    研究了聚烯烃弹性体(POE)改性沥青的结构和性能,考察了POE用量对两种基质沥青常规性能的影响,并用光学显微镜观察了POE在沥青中的分布状态.结果表明,随着POE用量增加,沥青的软化点增加,25℃针入度减小,高温性能变好.通过储存稳定性实验发现,POE改性沥青后稳定性较差.POE改性沥青相结构研究发现,随着POE用量的增加,POE由分散相变为连续相,POE质量分数为6%时,基质沥青发生相转变.%Polyolefin elastomer (POE) modified asphalt was studied.Two different base asphalts were mixed with POE at various contents.The properties and morphology of the modified asphalt were characterized by classical test methods and optical microscope.The results indicated that POE could improve the conventional properties of base asphalt,while the hot storage stable tests showed a poor compatibility with asphalt.The research of the phase structure showed that,dispersed POE granules changed to continuous phase with its increasing content,the phase transition began at about 6 % polymer content.

  18. Effect of base bitumen composition on asphalt rubber binder properties

    OpenAIRE

    Partl, M.N.; Ould-Henia, M.; Dumont, A.-G.

    2008-01-01

    The asphalt rubber blend properties are strongly related to its base components properties. The base bitumen composition is considered as a key factor influencing the final rheological properties of asphalt rubber binder. This paper describes results from a laboratory investigation of the interaction between crumb rubber and different composition bitumen according to the wet process. The bitumen composition is determined according to the SARA decomposition approac...

  19. DURABILITY OF ASPHALT CONCRETE MIXTURES USING DOLOMITE AGGREGATES

    Directory of Open Access Journals (Sweden)

    Imad Al-Shalout

    2015-12-01

    Full Text Available This study deals with the durability of asphalt concrete, including the effects of different gradations, compaction temperatures and immersion time on the durability potential of mixtures. The specific objectives of this study are: to investigate the effect of compaction temperature on the mechanical properties of asphalt concrete mixtures; investigate the effect of bitumen content and different aggregate gradations on the durability potential of bituminous mixtures.

  20. Mathematical Approach in Rheological Characterizing of Asphalt Emulsion Residues

    Directory of Open Access Journals (Sweden)

    Seong Hwan Cho

    2015-01-01

    Full Text Available Three different emulsion residues, such as SS1HP, HFE90, and SS-1VH (trackless, and a base asphalt binder (PG 64-22 are compared to characterize rheological properties by using DSR test. In order to capture the emulsion properties, different frequencies (from 1 to 100 rad/sec at a 10% constant shear rate and temperatures (from −45°C to 75°C with 15°C increments were applied. Then, a master curve for shear modulus was plotted for each emulsion. The transition of the HFE90 emulsion from viscous to elastic behavior occurs at lower temperatures, compared to the other materials. This emulsion is known for performing in a wider temperature range as shown in the results. The trackless emulsion presents an elastic behavior at intermediate temperatures. This product is known as having very fast setting and high resistance to shear stresses. The trackless emulsion presents the highest viscous and elastic modulus, followed by the PG 64-22 binder, SS1HP, and HFE90 emulsion. Shear strength test results show a behavior between trackless emulsion and SS1HP similar to the frequency sweep test results performed by DSR.

  1. Exposing the nonlinear viscoelastic behavior of asphalt-aggregate mixes

    Science.gov (United States)

    Levenberg, Eyal; Uzan, Jacob

    2012-05-01

    In this study asphalt-aggregate mixes are treated as both viscoelastic and viscoplastic. Following a damage mechanics approach, a nonlinear viscoelastic constitutive formulation is generated from a linear formulation by replacing `applied stresses' with `effective viscoelastic stresses'. A non-dimensional scalar entity called `relative viscoelastic stiffness' is introduced; it is defined as the ratio of applied to effective viscoelastic stress and encapsulates different types of nonlinearities. The paper proposes a computational scheme for exposing these nonlinearities by uncovering, through direct analysis of any test data, changes experienced by the `relative viscoelastic stiffness'. In general terms, the method is based on simultaneous application of creep and relaxation formulations while preserving the interrelationship between the corresponding time functions. The proposed scheme is demonstrated by analyzing a uniaxial tension test and a uniaxial compression test (separately). Results are presented and discussed, unveiling and contrasting the character of viscoelastic nonlinearities in both cases. A conceptual viewpoint is offered to explain the observations, illustrating the requirements from any candidate constitutive theory.

  2. Application of Common Mid-Point Method to Estimate Asphalt

    Science.gov (United States)

    Zhao, Shan; Al-Aadi, Imad

    2015-04-01

    3-D radar is a multi-array stepped-frequency ground penetration radar (GPR) that can measure at a very close sampling interval in both in-line and cross-line directions. Constructing asphalt layers in accordance with specified thicknesses is crucial for pavement structure capacity and pavement performance. Common mid-point method (CMP) is a multi-offset measurement method that can improve the accuracy of the asphalt layer thickness estimation. In this study, the viability of using 3-D radar to predict asphalt concrete pavement thickness with an extended CMP method was investigated. GPR signals were collected on asphalt pavements with various thicknesses. Time domain resolution of the 3-D radar was improved by applying zero-padding technique in the frequency domain. The performance of the 3-D radar was then compared to that of the air-coupled horn antenna. The study concluded that 3-D radar can be used to predict asphalt layer thickness using CMP method accurately when the layer thickness is larger than 0.13m. The lack of time domain resolution of 3-D radar can be solved by frequency zero-padding. Keywords: asphalt pavement thickness, 3-D Radar, stepped-frequency, common mid-point method, zero padding.

  3. Comparing Production and Placement of Warm-Mix Asphalt to Traditional Hot-Mix Asphalt for Constructing Airfield Pavements

    Science.gov (United States)

    2013-08-01

    pressure cells ( EPC ), single depth deflectometers (SDD), and asphalt strain gauges (ASG) are indicated by symbols denoted on the figures. Further...gauges, I-buttons, ASGs, SDDs, and EPCs to measure the pavement response to simulated aircraft loading. The asphalt concrete strain gauges (Figure 55...gauge in backscatter mode. The type of roller used for each pass is indicated on each figure. The contractor determined how many roller passes to use

  4. Quantitative exposure matrix for asphalt fume, total particulate matter, and respirable crystalline silica among roofing and asphalt manufacturing workers.

    Science.gov (United States)

    Fayerweather, William E; Trumbore, David C; Johnson, Kathleen A; Niebo, Ronald W; Maxim, L Daniel

    2011-09-01

    This paper summarizes available data on worker exposures to asphalt fume (soluble fraction), total particulate matter, and respirable crystalline silica (quartz) [hereinafter RCS] over a 30-year period in Owens Corning's asphalt production and roofing manufacturing plants. For the period 1977 through 2006, the air-monitoring database contains more than 1,400 personal samples for asphalt fume (soluble fraction), 2,400 personal samples for total particulate, and 1,300 personal samples for RCS. Unique process-job categories were identified for the asphalt production and roofing shingle manufacturing plants. Quantitative exposures were tabulated by agent, process-job, and calendar period to form an exposure matrix for use in subsequent epidemiologic studies of the respiratory health of these workers. Analysis of time trends in exposure data shows substantial and statistically significant exposure reductions for asphalt fume (soluble fraction), total particulate matter, and respirable crystalline silica at Owens Corning plants. Cumulative distribution plots for the most recent sampling period (2001-2006) show that 95% of the asphalt fume (soluble fraction) measurements were less than 0.25 mg/m3; 95% of the total particulate measurements were less than 2.2 mg/m3; and 95% of the RCS measurements were less than 0.05 mg/m3. Several recommendations are offered to improve the design of future monitoring efforts.

  5. Professionalising the asphalt construction process: aligning information technologies, operators' knowledge and laboratory practices

    NARCIS (Netherlands)

    Bijleveld, Frank Roland

    2015-01-01

    This research addresses the need to professionalise the asphalt construction process. A distinctive action research strategy is designed and carried out to progressively improve operational strategies of asphalt teams from technological, human (operator) and laboratory perspectives. Using informatio

  6. Research on Shearing Behavior of Domestic Epoxy Asphalt%国产环氧沥青混合料抗剪性能试验研究

    Institute of Scientific and Technical Information of China (English)

    钱振东; 陈磊磊; 尹祖超; 罗桑

    2011-01-01

    The 7610 type domestic epoxy asphalt was selected as the binder and the basalt with a nominal maximum aggregate size of 16 mm was selected as the aggregate, the epoxy asphalt mixtures with different gradations were formed using the gyratory compactor and tested through uniaxial penetration test.The shearing behaviors of asphalt mixture with different binders were compared according to the orthogonal test.The results show that the shearing performance of the thermosetting epoxy asphalt mixture is better than that of the normal asphalt mixtures, the asphalt content and the passing rate to 4.75 mm particle size are the major influencing factors.%选取国内研发的7610型环氧沥青为结合料,以最大公称粒径为16 mm的玄武岩为集料,利用单轴贯入试验对不同级配组成的环氧沥青混合料抗剪性能进行了试验研究,并采用正交试验法对不同沥青材料混合料的抗剪性能进行了对比.结果表明,环氧沥青混合料的抗剪性能远优于一般的沥青混合料,对其影响程度较大的因素主要是油石比和4.75 mm粒径通过率.

  7. Deformation behavior and load limits of asphaltic concrete under the conditions of cores in embankment dams; Deformationsverhalten und Belastungsgrenzen des Asphaltbetons unter den Bedingungen von Staudammkerndichtungen

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, U.

    1998-12-31

    Based on the analysis of existing dams with asphaltic diaphragm and investigations in the three-phase-system of asphaltic concrete a recipe for the composition of asphaltic cores is recommended. For the construction, rest and operating period of an embankment dam the load and the reaction of the asphaltic concrete cores as well as the appearing stress and deformations are described. Extensive material testings have been performed and at 41 asphaltic concrete specimens triaxial stress controlled pressure and creeping tests have been carried out. The evaluation of the triaxial tests led to proportions of the main stress and deformation limits as criteria of breaking. Under application of the standard equation for nonlinear viscoelastic element-laws a rheonom element formulation was developed from the experiment data and transformed into its differential form. With this approach the stress and deformation behavior of watertight asphaltic diaphragm can be precalculated for a period up to 10 years. The applicability of this approach, which can be also used within FE-calculations as well, is illustrated in four examples. (orig.) [Deutsch] Nach der Analyse bestehender Staudaemme mit Asphaltbetonkerndichtung und Untersuchungen zum Dreiphasensystem Asphaltbeton wird eine Rezepturempfehlung fuer den Asphaltkerndichtungsbau aufgestellt. Fuer die Bau-, Ruhe- und Betriebsphase eines Staudammes werden die Beanspruchungen und Reaktionen der Asphaltbetonkerndichtung sowie die auftretenden Spannungen und Verformungen beschrieben. Nach umfangreichen Materialpruefungen sind an 41 Asphaltbetonpruefkoerpern triaxiale spannungsgesteuerte Druck-Kriechversuche durchgefuehrt worden. Die Auswertung der Triaxialversuche ergab ein Grenzhauptspannungsverhaeltnis und Deformationsgrenzen als Bruchkriterien. Unter Verwendung der Standarformulierung fuer nichtlineare viskoelastische Stoffgesetze wurde aus den Versuchsdaten ein rheonomer Stoffansatz entwickelt und in seine differentielle Form

  8. Asphalt Roofing Shingles Into Energy Project Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Jameson, Rex, PE

    2008-04-28

    Based on a widely cited September, 1999 report by the Vermont Agency of Natural Resources, nearly 11 million tons of asphalt roofing shingle wastes are produced in the United States each year. Recent data suggests that the total is made up of about 9.4 million tons from roofing tear-offs and about 1.6 million tons from manufacturing scrap. Developing beneficial uses for these materials would conserve natural resources, promote protection of the environment and strengthen the economy. This project explored the feasibility of using chipped asphalt shingle materials in cement manufacturing kilns and circulating fluidized bed (CFB) boilers. A method of enhancing the value of chipped shingle materials for use as fuel by removing certain fractions for use as substitute raw materials for the manufacture of new shingles was also explored. Procedures were developed to prevent asbestos containing materials from being processed at the chipping facilities, and the frequency of the occurrence of asbestos in residential roofing tear-off materials was evaluated. The economic feasibility of each potential use was evaluated based on experience gained during the project and on a review of the well established use of shingle materials in hot mix asphalt. This project demonstrated that chipped asphalt shingle materials can be suitable for use as fuel in circulating fluidized boilers and cement kilns. More experience would be necessary to determine the full benefits that could be derived and to discover long term effects, but no technical barriers to full scale commercial use of chipped asphalt shingle materials in these applications were discovered. While the technical feasibility of various options was demonstrated, only the use of asphalt shingle materials in hot mix asphalt applications is currently viable economically.

  9. Investigating the Properties of Asphalt Concrete Containing Glass Fibers and Nanoclay

    OpenAIRE

    Hasan Taherkhani

    2016-01-01

    The performance of asphaltic pavements during their service life is highly dependent on the mechanical properties of the asphaltic layers. Therefore, in order to extend their service life, scientists and engineers are constantly trying to improve the mechanical properties of the asphaltic mixtures. One common method of improving the performance of asphaltic mixtures is using different types of additives. This research investigated the effects of reinforcement by randomly distributed glass fib...

  10. Study on Process for Manufacturing Heavy Traffic Asphalt from Gudong Crude

    Institute of Scientific and Technical Information of China (English)

    Wang Zijun; Long Jun; She Yucheng

    2004-01-01

    The Gudong crude from Gudao oil-bearing region in the Shengli oilfield was used as the target for studying the process of manufacturing heavy traffic road asphalt. The heavy traffic road asphalt products can be made from Gudong crude through blending residuum from mild thermal conversion of vacuum resid with extract, blending the deoiled asphalt from VR propane deasphalting with vacuum resid and the extract, and blending of oxidizedhard asphalt originated from VR with the extract.

  11. Structural and Thermal Analysis of Asphalt Solar Collector Using Finite Element Method

    OpenAIRE

    Jinshah Basheer Sheeba; Ajith Krishnan Rohini

    2014-01-01

    The collection of solar energy using asphalt pavements has got a wide importance in the present energy scenario. Asphalt pavements subjected to solar radiation can reach temperature up to 70°C because of their excellent heat absorbing property. Many working parameters, such as pipe diameter, pipe spacing, pipe depth, pipe arrangement, and flow rate, influence the performance of asphalt solar collector. Existing literature on thermal energy extraction from asphalt pavements is based on the sma...

  12. The Effect of Aggregate Property on Shear Performance of Asphalt Mixture%集料特性对沥青混合料抗剪性能的影响研究

    Institute of Scientific and Technical Information of China (English)

    许萌; 李志超; 陈杰

    2014-01-01

    从集料特性入手,通过单轴贯入试验和三轴压缩试验,研究分析不同集料类型和特性对AC-13沥青混合料抗剪性能的影响规律。研究表明,玄武岩沥青混合料的抗剪性能优于石灰岩,同时,减小集料的针片状颗粒含量、压碎值、磨耗值,提高其棱角性,能够增大沥青混合料的粘聚力和内磨擦角,从而提高沥青混合料的抗剪性能。%Beginning with the aggregate characteristics , this article analyzes the effect of different types and characteristics of aggregate on the shear performance of AC-13 asphalt mixture through the uniaxial penetration test and triaxial compression test .The research shows that the shear properties of basalt asphalt mixture is better than those of limestone and meanwhile the basalt asphalt mixture reduces the acicular content , crushing value as well as abrasion value , and also increases the angularity .Furthermore , the basalt asphalt mixture can improve the cohesion and internal friction angle of asphalt mixture and the shear performance of asphalt mixture as well .

  13. Relationship between Microstructure and Storage Stability of Modified Asphalt%改性沥青微观结构与储存稳定性的关系

    Institute of Scientific and Technical Information of China (English)

    严秋荣; 王建壮; 孔令云

    2015-01-01

    In accordance with the principle of fluorescence optical microscopy,morphology analysis of polymer modified asphalt and the mixed principle of modified asphalt,etc.,this paper carries out micro-observation for samples during preparation of modified asphalt with different types of SBS modifiers and asphalt of the same matrix,and meanwhile takes photos of its morphologies in different periods of time, and studies the relationship between morphologies and storage stability of modified asphalt in combination with the results of micro -observation and the results of separation test for modified asphalt.The study shows that analysis for existing morphologies of polymer modifiers during preparation of modified asphalt can provide bases for preparation temperature and time,etc.of modified asphalt;the easier the polymer modifiers is mixed in asphalt and the smaller the particle size,the better the stability of the prepared modified asphalt and the more remarkable the improvement of softening point;for asphalt of the same matrix,SBS modifier at larger block ratio shows good modified effect on matrix asphalt,and the stability of the prepared modified asphalt is better.%根据荧光显微照相原理、聚合物改性沥青的相态结构分析、改性沥青的混合原理等,对不同型号的SBS改性剂与同一基质沥青配制改性沥青过程中的样品进行显微观测,同时对其不同时段的相态结构进行照片拍摄,并结合微观观测结果与改性沥青离析试验结果,对改性沥青的相态结构与其存储稳定性之间的关系进行研究。研究表明:分析改性沥青制备过程中聚合物改性剂的存在相态,可为改性沥青制备温度、时间等提供依据;聚合物改性剂在沥青中越容易混合、粒径越小,所制备的改性沥青的稳定性越好,软化点的提高越显著;对同一基质沥青,嵌段比大的SBS改性剂对基质沥青的改性效果好,所制备的改性沥青稳定性更好。

  14. Asphalt fume exposure levels in North American asphalt production and roofing manufacturing operations.

    Science.gov (United States)

    Axten, Charles W; Fayerweather, William E; Trumbore, David C; Mueller, Dennis J; Sampson, Arthur F

    2012-01-01

    This study extends by 8 years (1998-2005) a previous survey of asphalt fume exposures within North American asphalt processing and roofing product manufacturing workers. It focuses on characterizing personal, full-shift samples and seeks to address several limitations of the previous survey. Five major roofing manufacturers with established occupational health programs submitted workplace asphalt fume sampling results to a central repository for review and analysis. A certified industrial hygienist-led quality assurance team oversaw the data collection, consolidation, and analysis efforts. The analysis dataset consisted of 1261 personal exposure samples analyzed for total particulate (TP) and benzene soluble fraction (BSF) using existing NIOSH methods. For BSF, the survey's arithmetic (0.25 mg/m(3), SD = 0.62) and geometric (0.12 mg/m(3), GSD = 2.88) means indicate that the industry has sustained the control levels achieved in the late 1980s, early 1990s. Similar results were found for TP. The survey-wide summary statistics are consistent with other post-1990 multi-company exposure studies. Although these findings indicate that currently available controls are capable of achieving substantial (95%) compliance with the current threshold limit value in asphalt processing and inorganic shingle and roll plants, they also show that the majority of plants are not achieving this level of exposure control, and that exposures are significantly higher in plants making other product lines, particularly organic felt products. The current retrospective survey of existing company exposure data, like its predecessor, has several important limitations. These include lack of data on smaller manufacturers and on several commercially important product lines; insufficient information on the prevalence and effectiveness of engineering controls; no standard criteria by which to define and assess exposures in non-routine operations; and a paucity of exposure data collected as part of a

  15. Performances and Durability of Asphalt Mixtures Made with Reclaimed Asphalt Pavement

    OpenAIRE

    Noferini, Luca

    2016-01-01

    According to most recent surveys, 265 mil tonnes of asphalt for road applications were produced in the European area in 2014. In the same year, the amount of available RAP was more than 50 mil tonnes. The use of RAP in new blended mixes reduces the need of neat bitumen, making RAP recycling economically attractive. In spite of its economic and environmental benefits, the use of RAP is often subjected to restrictive policies pursued by agencies due to uncertainty related to RAP mixes field per...

  16. The first engineered self-healing asphalt road: How is it performing?

    NARCIS (Netherlands)

    Liu, Q.; Schlangen, H.E.J.G.; Van Bochove, G.

    2013-01-01

    Porous asphalt shows excellent performance in both noise reduction and water drainage. Although porous asphalt has these great qualities, its service life is much shorter (sometimes only half) compared to dense graded asphalt roads. Ravelling, which is the loss of aggregate particles from the surfac

  17. 40 CFR 436.60 - Applicability; description of the asphaltic mineral subcategory.

    Science.gov (United States)

    2010-07-01

    ... asphaltic mineral subcategory. 436.60 Section 436.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY Asphaltic Mineral Subcategory § 436.60 Applicability; description of the asphaltic mineral subcategory....

  18. Specifications and Construction Methods for Asphalt Concrete and Other Plant-Mix Types, 3rd Edition.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    The purpose of this publication is to assist engineers in the analysis, design and control of paving projects that use asphalt concrete and other asphalt plant-mixes. The scope of this new third edition has been enlarged, and changes necessitated by advances in asphalt technology have been incorporated. Chapters I and II and Appendices A and B…

  19. Visualizing asphalt roller trajectories in context: acquiring, processing, and representing sensor readings

    NARCIS (Netherlands)

    Vasenev, Alexandr Nikolajevitsj

    2015-01-01

    The asphalt compaction process relies heavily on the skills and knowledge of roller operators who act alongside other stakeholders involved in asphalt paving. It is essential that these construction specialists: (1) are adequately informed about the initial temperature distribution of the asphalt la

  20. On the representative volume element of asphalt concrete at low temperature

    Science.gov (United States)

    Marasteanu, Mihai; Cannone Falchetto, Augusto; Velasquez, Raul; Le, Jia-Liang

    2016-08-01

    The feasibility of characterizing asphalt mixtures' rheological and failure properties at low temperatures by means of the Bending Beam Rheometer (BBR) is investigated in this paper. The main issue is the use of thin beams of asphalt mixture in experimental procedures that may not capture the true behavior of the material used to construct an asphalt pavement.

  1. ASPHALT FOR OFF-STREET PAVING AND PLAY AREAS, 3RD EDITION.

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

    THIS PAMPHLET DISCUSSES THE ALTERNATIVE METHODS, APPLICATIONS, AND TECHNICAL CONSIDERATIONS FOR OFF-STREET PAVING AND PLAY AREAS. OFF-STREET PAVING INCLUDES--(1) ASPHALT-PAVED PARKING AREAS, (2) ROOF DECK PARKING AREAS, (3) ASPHALT-PAVED DRIVEWAYS, (4) ASPHALT-PAVED SERVICE STATION LOTS, AND (5) SIDEWALKS. THE DISCUSSION OF PLAY AREAS…

  2. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Science.gov (United States)

    2010-07-01

    ... Manufacturing (Coating) Operations 2 Table 2 of Subpart AAAAAAA of Part 63 Protection of Environment... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * *...

  3. The Use of Coal Bottom Ash In Hot Mix Asphalt

    Directory of Open Access Journals (Sweden)

    Charles Begyina Kodjo Nketsiah

    2015-05-01

    Full Text Available Bottom ash is a waste material from coal burnt to generate electric power. It is incombustible and non-biodegradable; hence, the best way to dispose it is by recycling rather than incineration and land filling. Past research on bottom ash in road building have focused mainly on embankment filling, sub-base and base courses; except boiler slag which has received much attention in Hot Mix Asphalt (HMA. Bottom ash from Tanjung Bin Power Station was thus investigated through laboratory testing to justify its use in HMA construction in Malaysia. This Paper analysed the data with regards to performance in HMA. In the Marshall Mix design, the material largely satisfied the Stability, Flow and Stiffness requirements which were comparable to that of conventional aggregates, although void contents were a bit higher. When blended with granite, all the parameters were met. Contrary to past suggestions that bottom ash in HMA consumes more bitumen, the 6.4% (51.20g Optimum Bitumen Content (OBC achieved in this study does not necessarily translate into high consumption, compared to OBC of 5.3% (59.63g in the case of granite. The HMA also proved to be highly resistant to moisture-induced damage and satisfied the minimum JKR specification for Static Uniaxial Load Strain.

  4. Image analysis of aggregate,mastic and air void phases for asphalt mixture%Image analysis of aggregate, mastic and air void phases for asphalt mixture

    Institute of Scientific and Technical Information of China (English)

    ADHIKARI Sanjeev; YOU Zhan-ping; HAO Pei-wen; WANG Hai-nian

    2013-01-01

    The shape characterization and spatial distribution of aggregate,mastic and air void phases for asphalt mixture were analyzed.Three air void percentage asphalt mixtures,4%,7% and 8%,respectively,were cut into cross sections and polished.X-ray scanning microscope was used to capture aggregate,mastic,air void phase by the image.The average of polygon diameter was chosen as a threshold to determine which aggregates would be retained on a given sieve.The aggregate morphological image from scanned image was utilized by digital image processing method to calculate the gradation of aggregate and simulate the real gradation.Analysis result shows that the air void of asphalt mixture has influence on the correlation between calculation gradation and actual gradation.When comparing 4.75 mm sieve size of 4%,7% and 8% air void asphalt mixtures,7% air void asphalt mixture has 55% higher than actual size gradation,8% air void asphalt mixture has 8% higher than actual size gradation,and 4% air void asphalt mixture has 3.71% lower than actual size gradation.4% air void asphalt mixture has the best correlation between calculation gradation and actual gradation comparing to other specimens.The air void percentage of asphalt mixture has no obvious influence on the air void orientation,and three asphalt mixtures show the similar air orientation along the same direction.4 tabs,7 figs,17 refs.

  5. Inhalation and dermal exposure among asphalt paving workers.

    Science.gov (United States)

    McClean, M D; Rinehart, R D; Ngo, L; Eisen, E A; Kelsey, K T; Herrick, R F

    2004-11-01

    The primary objective of this study was to identify determinants of inhalation and dermal exposure to polycyclic aromatic compounds (PACs) among asphalt paving workers. The study population included three groups of highway construction workers: 20 asphalt paving workers, as well as 12 millers and 6 roadside construction workers who did not work with hot-mix asphalt. During multiple consecutive work shifts, personal air samples were collected from each worker's breathing zone using a Teflon filter and cassette holder connected in series with an XAD-2 sorbent tube, while dermal patch samples were collected from the underside of each worker's wrist. All exposure samples were analyzed for PACs, pyrene and benzo[a]pyrene. Inhalation and dermal PAC exposures were highest among asphalt paving workers. Among paving workers, inhalation and dermal PAC exposures varied significantly by task, crew, recycled asphalt product (RAP) and work rate (inhalation only). Asphalt mix containing high RAP was associated with a 5-fold increase in inhalation PAC exposures and a 2-fold increase in dermal PAC exposure, compared with low RAP mix. The inhalation PAC exposures were consistent with the workers' proximity to the primary source of asphalt fume (paver operators > screedmen > rakers > roller operators), such that the adjusted mean exposures among paver operators (5.0 microg/m3, low RAP; 24 microg/m3, high RAP) were 12 times higher than among roller operators (0.4 microg/m3, low RAP; 2.0 microg/m3, high RAP). The dermal PAC exposures were consistent with the degree to which the workers have actual contact with asphalt-contaminated surfaces (rakers > screedmen > paver operators > roller operators), such that the adjusted mean exposures among rakers (175 ng/cm2, low RAP; 417 ng/cm2, high RAP) were approximately 6 times higher than among roller operators (27 ng/cm2, low RAP; 65 ng/cm2, high RAP). Paving task, RAP content and crew were also found to be significant determinants of

  6. 再生剂对沥青再生机理的影响研究%Research on Asphalt Recycling Mechanism Based on Different Recycling Agents

    Institute of Scientific and Technical Information of China (English)

    聂忆华; 刘苹; 周志刚; 侯月军; 戴旭

    2012-01-01

    Asphalt recycling mechanism is studied in the paper, based on four components tests for aging asphalt and recycling asphalt with different recycling agents, by comparing and analyzing the D - value between testing data and theory data. Results show that recycling asphalt four components are not all coming from origin material directly, some of them is from chemical reaction between four components. The exchange direction and quantity of four components is not same to one old asphalt, witch relate to type and addition of recycling agent. The study results can provide important theoretical basis for sustainable use and development of recycling asphalt.%基于老化沥青与不同再生剂再生后的四组分试验,采用理论与实测数据对比分析法,探讨了沥青再生时组分调和理论的适应性.研究分析表明:沥青再生时为组分不完全调和,四组分之间发生了少量的化学反应移行;同一老化沥青再生时,四组分化学移行方向、化学反应数量均不是固定的,与再生剂类型、掺量有关.本研究发现为沥青混凝土老化再生利用技术可持续发展提供重要理论依据.

  7. An Approach for Nonlinear Fatigue Damage Evaluation in Asphalt Pavements

    Science.gov (United States)

    Rajbongshi, Pabitra; Thongram, Sonika

    2016-09-01

    Fatigue due to vehicular loads is one of the primary distress mechanisms in asphalt pavements. It happens primarily due to deterioration in asphalt material with load repetitions. Degradation of asphalt material may be evaluated using different parameters. In view of degradation, the incremental damage in a given pavement section would be different for different repetitions, even with same loadings. Therefore, the damage progression becomes nonlinear with repetitions. Accounting such nonlinearity in damage accumulation, and based on different damage evaluation parameters, this paper presents an equivalent approach for fatigue damage evaluation in asphalt pavements. Traditional fatigue equation adopted in mechanistic-empirical pavement design has been used in the present work. Four different criteria, namely number of load repetitions, asphalt stiffness reduction, strain enhancement and fatigue life reduction with repetitions are considered for damage estimation. The proposed approach could estimate same value of nonlinear damage, irrespective of the criteria used. The simplest form of criterion i.e. the number of load repetitions can be used for fatigue performance evaluation. Probabilistically, the damage propagation is also correlated and assessed with the failure probability.

  8. Tetrapyrroles and associated compounds in Dead Sea asphalts

    Energy Technology Data Exchange (ETDEWEB)

    Aizenshtat, Z. (Hebrew Univ. of Jerusalem, Israel); Dinur, D.; Nissenbaum, A.

    1979-01-01

    Metallo- and free porphyrins (1000 to 1500 ppM) isolated from asphalts occurring as huge blocks floating in the northern part of the Dead Sea, have been analyzed by visible-uv (v-uv) spectrophotometry and by mass spectrometry. The concentration of vanadyl porphyrins in the asphalts exceeds by far that of the Ni-porphyrins, despite the l:3 V/Ni ratio found in the total asphalt sample. The free porphyrins resemble those from the Uinta Basin (USA) gilsonite and contain a mixture of homologous Aetio- and deoxyphyllo-erythroaetioporphyrins (DPEP). The non-porphyrin fraction of the asphalt showed an identical aliphatic, hydrocarbon distribution with that of heavy crude oil from the same area. The more polar fraction associated with the porphyrins was compared with the polar fraction of the previously described ozokerite from the Dead Sea area. From high-resolution MS, IR, v-uv and NMR spectra, combined with hydrolysis and GLC analysis, it is suggested that even-numbered (C/sub 12/, C/sub 16/, C/sub 18/, C/sub 18/ /sub 1/, C/sub 22/) fatty acids are associated with the asphaltic porphyrins, probably in the triglyceride form.

  9. Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

    Science.gov (United States)

    Fullová, Daša; Đurčanská, Daniela

    2016-12-01

    The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  10. UTILIZATION OF WASTE PLASTIC BOTTLES IN ASPHALT MIXTURE

    Directory of Open Access Journals (Sweden)

    TAHER BAGHAEE MOGHADDAM

    2013-06-01

    Full Text Available Nowadays, large amounts of waste materials are being produced in the world. One of the waste materials is plastic bottle. Generating disposable plastic bottles is becoming a major problem in many countries. Using waste plastic as a secondary material in construction projects would be a solution to overcome the crisis of producing large amount of waste plastics in one hand and improving the structure’s characteristics such as resistance against cracking on the other hand. This study aimed to investigate the effects of adding plastic bottles in road pavement. Marshall properties as well as specific gravity of asphalt mixture containing different percentages of plastic bottles were evaluated. Besides, Optimum Asphalt Content (OAC was calculated for each percentages of plastic bottles used in the mix. The stiffness and fatigue characteristics of mixture were assessed at OAC value. Results showed that the stability and flow values of asphalt mixture increased by adding waste crushed plastic bottle into the asphalt mixture. Further, it was shown that the bulk specific gravity and stiffness of mixtures increased by adding lower amount of plastic bottles; however, adding higher amounts of plastic resulted in lower specific gravity and mix stiffness. In addition, it was concluded that the mixtures containing waste plastic bottles have lower OAC values compared to the conventional mixture, and this may reduce the amount of asphalt binder can be used in road construction projects. Besides, the mixtures containing waste plastic showed significantly greater fatigue resistance than the conventional mixture.

  11. Recovery and reuse of asphalt roofing waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Desai, S.; Graziano, G.; Shepherd, P.

    1984-02-02

    Burning of asphalt roofing waste as a fuel and incorporating asphalt roofing waste in bituminous paving were identified as the two outstanding resource recovery concepts out of ten studied. Four additional concepts might be worth considering under different market or technical circumstances. Another four concepts were rated as worth no further consideration at this time. This study of the recovery of the resource represented in asphalt roofing waste has identified the sources and quantities of roofing waste. About six million cubic yards of scrap roofing are generated annually in the United States, about 94% from removal of old roofing at the job site and the remainder from roofing material production at factories. Waste disposal is a growing problem for manufacturers and contractors. Nearly all roofing waste is hauled to landfills at a considerable expense to roofing contractors and manufacturers. Recovery of the roofing waste resource should require only a modest economic incentive. The asphalt contained in roofing waste represents an energy resource of more than 7 x 10/sup 13/ Btu/year. Another 1 x 10/sup 13/ Btu/year may be contained in field-applied asphalt on commercial building roofs. The two concepts recommended by this study appear to offer the broadest applicability, the most favorable economics, and the highest potential for near-term implementation to reuse this resource.

  12. Determination of Rheological Properties of Bio Mastic Asphalt

    Directory of Open Access Journals (Sweden)

    R. Muniandy

    2008-01-01

    Full Text Available Due to the high oil prices the price of asphalt binder has increased tremendously. This scenario has warranted demand for higher viscosity cheaper asphalt for pavement construction. A study was conducted to take advantage of the Empty Fruit Bunch (EFB of Date and Oil Palm trees (which are considered as waste to produce cellulose fiber to be used as additives in the asphalt binder. If these EFB's could be beneficially utilized in any application, it would reduce the load on the nation's landfills and at the same time reducing the cost of road construction. A total of 11 blends were prepared that consisted of 5 blends with date palm fiber, 5 blends with oil palm fiber and one control sample that contained no fibers. The samples were evaluated using Dynamic Shear Rheometer (DSR equipment in accordance with the superpave Strategic Highway Research Program (SHRP requirements. The neat asphalt binders (Unaged, Rolling Thin Film Oven (RTFO aged and Pressure Ageing Vessel (PAV samples were then measured for phase angle, shear strain and complex shear modulus and then evaluated in accordance with SHRP requirements. The results indicated that the fibers enhanced the rheological performance of Bio Mastic Asphalt (BMA blends. The control sample which was categorized as PG58 was enhanced to PG76 with 0.375% date palm fiber. The oil palm has also improved the blend up to PG70 with 0.3% oil palm fiber.

  13. Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

    Directory of Open Access Journals (Sweden)

    Fullová Daša

    2016-12-01

    Full Text Available The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  14. STATE OF TRANSPORT PROCESSES FOR REPAIRING AND ASPHALTING OF ASPHALT ROADS AND WAYS THEIR DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Nikolaev N. N.

    2015-04-01

    Full Text Available The article explains the importance of the transport process when performing repair jobs of asphalt roads. The scheme of the technological process was drawn up; job steps were identified, while the latter may be characterized by non-productive downtime of transport as well as that one of technological machines. We have analyzed the following steps of the flowchart of the road concrete mix transportation: the preparation of the road concrete mix for transportation, loading, transportation, unloading, laying and packing. The transportation of goods starts at the working site of their production and ends at the site of their consumption. The transportation process is a multistep and multioperational process having the greater diversity of technological, operational and economic operations, which must be correctly organized. It is extremely important to deliver the road concrete mix of coating plant (OP just in time, while avoiding the unproductive idle standing of the equipment, the deterioration of the mixture, as well as performing the job steps at minimum transportation cost savings. The successful combining of the steps of the concept organization of the road concrete mix transportation (coating plant, asphalt laying step, transportation step will improve the performance and will provide the reduction of the job cost. One must perform the coordination of job steps on different road sections using information technologies and communication facility

  15. Production of De-asphalted Oil and Fine Asphalt Particles by Supercritical Extraction

    Institute of Scientific and Technical Information of China (English)

    赵锁奇; 许志明; 王仁安

    2003-01-01

    A continuous three-stage supercritical fluid extraction (SFE) process with a capacity of 1.0kg.h-1 was setup to extract petroleum residue by pentane to obtain more oil for further upgrading. A discharging system integrated to the bottom of the extractor was used to recover solvent as gas while asphalt was obtained as fine particles. The influence of operating conditions on the yield and quality of extracts, i.e., deasphalted oil (DAO) and resin, was studied in the range of temperature 150-220℃, pressure of 4.0-6.0 MPa and the mass ratio of solvent to oil feed (S/O) 2.5-5.0. The particle size distribution, apparent forms and the packing density, which vary with operating pressure, were measured. The particle structures were observed by SEM as well. With the modification to conventional processes, furnace can be eliminated for solvent recovery from asphalt phase, so as to reduce energy consumption.

  16. The effect of mineralogy, texture and mechanical properties of anti-skid and asphalt aggregates on urban dust

    OpenAIRE

    RÀisÀnen, M.; Kupiainen, K.; Tervahattu, H.

    2003-01-01

    In northern latitudes mineral dust is formed when cars use studded tyres and roads are sanded to obtain more traction on the icy surfaces. Anti-skid and asphalt aggregates with different textural, mineralogical and mechanical properties were tested with an indoor road simulator fitted with studded and friction tyres. The particle size distribution and proportions of dust from pavement and anti-skid aggregate were analyzed using SEM-EDX. The wear on the road pavement...

  17. Bitumen modifiers for reduced temperature asphalts: a comparative analysis between three polymeric and non-polymeric additives

    OpenAIRE

    Cuadri Vega, Antonio Abad; Carrera Páez, Virginia; Izquierdo Rodríguez, María Angeles; García Morales, Moisés; Navarro Domínguez, Francisco Javier

    2014-01-01

    This study presents three bitumen modifiers which may find successful application in the fabrication of binders for warm mix asphalt in the paving industry. In that sense, two non-polymeric additives, thiourea and thiourea dioxide, along with a reactive isocyanate-terminated prepolymer have been evaluated. Viscous flow and linear viscoelasticity tests, at 60 ºC, reveal bituminous modified binders which evolve towards highly viscous materials when subjected to ambient curing. However, at 135 º...

  18. Generation of urban road dust from anti-skid and asphalt concrete aggregates.

    Science.gov (United States)

    Tervahattu, Heikki; Kupiainen, Kaarle J; Räisänen, Mika; Mäkelä, Timo; Hillamo, Risto

    2006-04-30

    Road dust forms an important component of airborne particulate matter in urban areas. In many winter cities the use of anti-skid aggregates and studded tires enhance the generation of mineral particles. The abrasion particles dominate the PM10 during springtime when the material deposited in snow is resuspended. This paper summarizes the results from three test series performed in a test facility to assess the factors that affect the generation of abrasion components of road dust. Concentrations, mass size distribution and composition of the particles were studied. Over 90% of the particles were aluminosilicates from either anti-skid or asphalt concrete aggregates. Mineral particles were observed mainly in the PM10 fraction, the fine fraction being 12% and submicron size being 6% of PM10 mass. The PM10 concentrations increased as a function of the amount of anti-skid aggregate dispersed. The use of anti-skid aggregate increased substantially the amount of PM10 originated from the asphalt concrete. It was concluded that anti-skid aggregate grains contribute to pavement wear. The particle size distribution of the anti-skid aggregates had great impact on PM10 emissions which were additionally enhanced by studded tires, modal composition, and texture of anti-skid aggregates. The results emphasize the interaction of tires, anti-skid aggregate, and asphalt concrete pavement in the production of dust emissions. They all must be taken into account when measures to reduce road dust are considered. The winter maintenance and springtime cleaning must be performed properly with methods which are efficient in reducing PM10 dust.

  19. Possibilities of preparation asphalt concrete by oil sands of Kazakhstan

    Directory of Open Access Journals (Sweden)

    Erbol Tileuberdi

    2012-12-01

    Full Text Available In the paper physicochemical properties of oil sands of Munayli-Mola deposits and efficient ways to use them for preparing asphalt concrete were represented. For determination of organic part of oil sands the extraction methods were used in Soxhlet apparatus by variety of solvents. It has been established 16 wt.% content of natural bitumen in oil sands, which compared with results of ash content determination. According to results of experiment, the natural bitumen is heavy oil and its characteristics close to characteristics of paving bitumen. The optimum content of oil sands in asphalt mix are 28 and 47 mass %, the mixes prepared under these conditions satisfy standard requirements of the Republic of Kazakhstan on the asphalt mixture ST RK 1225-2003.

  20. 温再生沥青混合料路用性能的试验研究%Research on the pavement performance of warm- recycled asphalt mixture

    Institute of Scientific and Technical Information of China (English)

    张德豪; 刘岩

    2015-01-01

    温再生沥青混合料是一种基于温拌沥青技术的新型再生沥青混合料,实现了旧沥青混合料(RAP)循环利用和节能减排的双重目标。本文通过与热再生沥青混合料的对比试验,研究了不同旧料掺量下温再生沥青混合料的路用性能。结果表明:温再生沥青混合料各项指标均已接近或达到了热再生沥青混合料的性能,而且旧料的掺配率可以提高10%左右;旧料掺量为20~30%时,温再生混合料的性能良好,可用于城市道路沥青路面的建设。%Warm-recycled asphalt mixture is a new type of pavement material that can realize the RAP recycling and energy saving and emission reduction. Trough the comparative test of hot-recycled asphalt mixture, the article studied the comprehensive pavement performance of warm-recycled asphalt mixture with the addition of different reclaimed asphalt pavement(RAP) admixture amount. The results showed that: all indicators of the warm- recycled asphalt mixture were close to or reached the performance of hot-recycled asphalt mixture,and the admixture amount of RAP can be improved about 10%. The RAP content should be among 20~30% when the WMA recycled mixture used in high grade highway construction.

  1. Effect of Material Composition and Environmental Condition on Thermal Characteristics of Conductive Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Pan Pan

    2017-02-01

    Full Text Available Conductive asphalt concrete with high thermal conductivity has been proposed to improve the solar energy collection and snow melting efficiencies of asphalt solar collector (ASC. This paper aims to provide some insight into choosing the basic materials for preparation of conductive asphalt concrete, as well as determining the evolution of thermal characteristics affected by environmental factors. The thermal properties of conductive asphalt concrete were studied by the Thermal Constants Analyzer. Experimental results showed that aggregate and conductive filler have a significant effect on the thermal properties of asphalt concrete, while the effect of asphalt binder was not evident due to its low proportion. Utilization of mineral aggregate and conductive filler with higher thermal conductivity is an efficient method to prepare conductive asphalt concrete. Moreover, change in thermal properties of asphalt concrete under different temperature and moisture conditions should be taken into account to determine the actual thermal properties of asphalt concrete. There was no noticeable difference in thermal properties of asphalt concrete before and after aging. Furthermore, freezing–thawing cycles strongly affect the thermal properties of conductive asphalt concrete, due to volume expansion and bonding degradation.

  2. [Biological monitoring of PAH exposure among asphalt workers].

    Science.gov (United States)

    Campo, Laura; Calisti, Roberto; Polledri, Elisa; Barretta, Francesco; Stopponi, Roberta; Massacesi, Stefania; Bertazzi, Pieralberto; Fustinoni, Silvia

    2011-01-01

    Aim of this work was the assessment of exposure to polycyclic aromatic hydrocarbons (PAHs) by urinary 1-hydroxypyrene (1-OHPyr) in asphalt workers. Median levels of 1-OHPyr resulted higher in asphalt workers than in controls (184 vs. < 20 ng/L, p < 0.001). The determinants of exposure of 1-OHPyr resulted smoking habit, the number of consecutive days at work and the job task; 1-OHPyr was also associated to urinary creatinine. End of work week 1-OHPyr is suggested as an useful indicator of occupational exposure to PAHs in bitumen fumes.

  3. Criteria for asphalt-rubber concrete in civil airport pavements: Mixture design

    Science.gov (United States)

    Roberts, F. L.; Lytton, R. L.; Hoyt, D.

    1986-07-01

    A mixture design procedure is developed to allow the use of asphalt-rubber binders in concrete for flexible airport pavement. The asphalt-rubber is produced by reacting asphalt with ground, scrap tire rubber to produce the binder for the asphalt-rubber concrete. Procedures for laboratory preparation of alsphalt-rubber binders using an equipment setup that was found by researchers to produce laboratory binders with similar properties to field processes are included. The rubber-asphalt concrete mixture design procedure includes adjustments to the aggregate gradation to permit space for the rubber particles in the asphalt-rubber binder as well as suggested mixing and compaction temperatures, and compaction efforts. While the procedure was used in the laboratory to successfully produce asphalt-rubber concrete mixtures, it should be evaluated in the field to ensure that consistent results can be achieved in a production environment.

  4. Road safety effects of porous asphalt: a systematic review of evaluation studies

    DEFF Research Database (Denmark)

    Elvik, R.; Greibe, Poul

    2005-01-01

    This paper presents a systematic review of studies that have evaluated the effects on road safety of porous asphalt. Porous asphalt is widely used on motorways in Europe, mainly in order to reduce traffic noise and increase road capacity. A meta-analysis was made of six studies, containing a total...... of eighteen estimates of the effect of porous asphalt on accident rates. No clear effect on road safety of porous asphalt was found. All summary estimates of effect indicated very small changes in accident rates and very few were statistically significant at conventional levels. Studies that have evaluated...... the effects of porous asphalt on nine different risk factors associated with accident occurrence were also reviewed. It was found that four of the risk factors were favourably influenced by porous asphalt, three were adversely influenced, and two were not influenced by porous asphalt. The net impact...

  5. [Anesthetic management in a patient with head and neck burn by asphalt].

    Science.gov (United States)

    Suzuki, Nao; Niiyama, Yukitoshi; Tokinaga, Yasuyuki; Yamakage, Michiaki

    2013-10-01

    In cases of facial burns caused by molten asphalt, examination for possible airway burns and early removal of the asphalt should be carried out to prevent chemical-induced tissue damage and infection. However, asphalt that has adhered to tissues is difficult to remove. A 35-year-old male with burns caused by molten asphalt was scheduled for emergency debridement. He had 6% body surface area burns on his face and neck. He was not able to open his eyes due to the adherence of asphalt. His respiratory condition was stable and a perioperative fiberoptic view revealed no airway burns. After awake intubation, orange peel oil was used to remove the asphalt from his face and eyes. Since orange peel oil does not contain any harmful substances, it is effective for removing asphalt without causing tissue damage.

  6. Essential work of fracture approach to fatigue grading of asphalt binders

    Science.gov (United States)

    Andriescu, Adrian

    The main objective of this thesis was to apply failure mechanics principles to the characterization of fatigue cracking of asphalt pavements and to identify the correlations between the pavement performance and the composition of binders. The essential work of fracture (EWF) method developed herein is an energy-based testing approach used for the fracture characterization of ductile materials. Developed for both binders and asphalt mixtures, the method provides fundamental parameters, such as specific essential work of fracture and critical tip opening displacement, as potential candidates for a better fatigue specification. It was shown that binders from different sources and with the same performance grade can have very different levels of fatigue susceptibility depending on their manufacturing method and hence failure properties. Also, the currently used binder loss modulus as developed by the Strategic Highway Research Program does not correlate with the newly proposed fracture mechanics based parameters. An extensive theological and ductile failure investigation on a large interval of testing conditions was performed for a group of binders that are used in the recently built test sections of Highway 655 in northern Ontario. It was found that the shift factors used in the construction of the master curves of the ductile fracture parameters differ from the shift factors of the rheological master curves. The difference was attributed to the response of the internal structure of the binder at the high strain levels that precede the failure phenomenon.

  7. Synthesis and properties of a clean and sustainable deicing additive for asphalt mixture.

    Directory of Open Access Journals (Sweden)

    Chao Peng

    Full Text Available A clean and sustainable deicing additive was prepared via the adsorption of acetate anions (Ac- by magnesium (Mg and aluminum (Al calcined layered double hydroxide (Mg/Al-CLDH. Fourier transform infrared spectroscopy spectrums proved that Ac- had intercalated into LDH structure. X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy images showed that the intercalation spacing and platelet thickness of Mg and Al layered double hydroxide containing Ac- anions (Mg/Al-Ac- LDH had been enlarged due to substitution of divalent CO32- anions by a larger quantity of monovalent Ac- anions. Differential scanning calorimetry tests testified that the insoluble Mg2/Al-Ac- LDH evidently decreased the freeze point (FP of water to -10.68°C. X-ray photoelectron spectroscopy analyses confirmed that the Ac- were strongly confined by the metal layers of LDHs. FP test of asphalt mixtures confirmed that Mg/Al-Ac- LDHs reduced FP to -5.5°C. Immersion test results indicated that Mg/Al-Ac- LDH had a good deicing durability and Ac- did not released from asphalt mixture. Snow melting observation was conducted further testified that Mg/Al-Ac- LDH melted snow or ice sustainably.

  8. Synthesis and properties of a clean and sustainable deicing additive for asphalt mixture.

    Science.gov (United States)

    Peng, Chao; Yu, Jianying; Zhao, Zhijie; Dai, Jing; Fu, Jingyi; Zhao, Meiling; Wang, Wei

    2015-01-01

    A clean and sustainable deicing additive was prepared via the adsorption of acetate anions (Ac-) by magnesium (Mg) and aluminum (Al) calcined layered double hydroxide (Mg/Al-CLDH). Fourier transform infrared spectroscopy spectrums proved that Ac- had intercalated into LDH structure. X-ray diffraction patterns, scanning electron microscopy and transmission electron microscopy images showed that the intercalation spacing and platelet thickness of Mg and Al layered double hydroxide containing Ac- anions (Mg/Al-Ac- LDH) had been enlarged due to substitution of divalent CO32- anions by a larger quantity of monovalent Ac- anions. Differential scanning calorimetry tests testified that the insoluble Mg2/Al-Ac- LDH evidently decreased the freeze point (FP) of water to -10.68°C. X-ray photoelectron spectroscopy analyses confirmed that the Ac- were strongly confined by the metal layers of LDHs. FP test of asphalt mixtures confirmed that Mg/Al-Ac- LDHs reduced FP to -5.5°C. Immersion test results indicated that Mg/Al-Ac- LDH had a good deicing durability and Ac- did not released from asphalt mixture. Snow melting observation was conducted further testified that Mg/Al-Ac- LDH melted snow or ice sustainably.

  9. Study on Property of Castor Oil Based Polyurethane Modified Asphalt%蓖麻油基聚氨酯改性沥青的性能研究

    Institute of Scientific and Technical Information of China (English)

    夏磊; 张海燕; 曹东伟; 郭燕生

    2016-01-01

    To develop a new type of modified asphalt and its preparation process, the castor oil contained asphalt is obtained with green renewable castor oil instead of petroleum based polyols at first, then the second monomer liquefied MDI is slowly dropped into pitch system with shearing and the castor oil based polyurethane ( PU) modified asphalt is prepared. The dosage of castor oil and the second monomer MDI are calculated by isocyanate index R( -NCO/ -OH) =1. 8, and the modified asphalt with 10% -30% content of castor oil based PU are synthesized. The performance of modified asphalt are characterized by conventional experiment. The experiment result shows that the modifier in asphalt dispersed evenly and both the high and low temperature performance of the castor oil based PU modified asphalt are improved, especially the high temperature performance. The high temperature grade of asphalt is determined by the original grade test and thin film oven tests ( TFOT) grade test on the samples. On the basis of high temperature grade, the high temperature performances of different asphalts after aging are analysed and evaluated by multiple stress creep recovery ( MSCR) test. The result shows that the creep compliance of the modified asphalt declined greatly and recovery rate raised obviously compared with base asphalt, which effectively achieved the effect of increasing elasticity and stiffening. With the increase of the modifier dosage, creep compliance declined and recovery rate raised in the same time, the modification effect is better.%为开发一种新型改性沥青及其制备工艺,以绿色可再生的蓖麻油代替石油基多元醇,先制成含油沥青,在沥青体系中再缓慢滴加第二单体液化二苯基甲烷二异氰酸酯(MDI),边剪切边制成蓖麻油基聚氨酯改性沥青.通过异氰酸酯指数R(-NCO/-OH)=1.8,按10%~30%总体改性剂掺量,计算出蓖麻油及第二单体MDI的用量,分别制备10%~30%的蓖麻油基聚氨酯改性沥青.通

  10. An Algorithm for Automatic Road Asphalt Edge Delineation from Mobile Laser Scanner Data Using the Line Clouds Concept

    Directory of Open Access Journals (Sweden)

    Carlos Cabo

    2016-09-01

    Full Text Available Accurate road asphalt extent delineation is needed for road and street planning, road maintenance, and road safety assessment. In this article, a new approach for automatic roadside delineation is developed based on the line clouds concept. The method relies on line cloud grouping from point cloud laser data. Using geometric criteria, the initial 3D LiDAR point data is structured in lines covering the road surface. These lines are then grouped according to a set of quasi-planar restriction rules. Road asphalt edge limits are extracted from the end points of lines belonging to these groups. Finally a two-stage smoothing procedure is applied to correct for edge occlusions and other anomalies. The method was tested on a 2.1 km stretch of road, and the results were checked using a RTK-GNSS measured dataset as ground truth. Correctness and completeness were 99% and 97%, respectively.

  11. The humoral immune response of mice exposed to simulated road paving-like asphalt fumes.

    Science.gov (United States)

    Anderson, Stacey E; Munson, Albert E; Tomblyn, Seth; Meade, B Jean; Diotte, Nicole M

    2008-07-01

    Asphalt is a complex mixture of organic molecules, including polycyclic aromatic hydrocarbons (PAH), which have been reported to cause serious adverse health effects in humans. Workers in manufacturing and construction trades exposed to asphalt are potentially at risk for being exposed to asphalt fumes and PAHs. Epidemiological investigations have collected mounting evidence that chemicals found in asphalt fumes present carcinogenic and possibly immunotoxic hazards. Studies evaluating the immunotoxic effects of asphalt fume are limited due to the large number of variables associated with asphalt fume exposures. This work investigates the immuno-toxic effects of road paving-like asphalt fume by analyzing the in vivo IgM response to a T-dependent antigen after exposure to whole, vapor, and particulate phase road paving-like asphalt fumes and asphalt fume condensate. Systemic exposures via intraperitoneal injection of asphalt fume condensate (at 0.625 mg/kg) and the particulate phase (at 5 mg/kg) resulted in significant reductions in the specific spleen IgM response to SRBC. Pharyngeal aspiration of the asphalt fume condensate (at 5 mg/kg) also resulted in significant suppression of the IgM response to SRBC. A significant reduction in the specific spleen IgM activity was observed after inhalation exposure to whole asphalt fumes (35 mg/m(3)) and the vapor components (11 mg/m(3)). Dermal exposures to the asphalt fume condensate resulted in significant reductions in the total (at 50 mg/kg) and specific (at 250 mg/kg) spleen IgM response to SRBC. These results demonstrate that exposure to road paving-like asphalt fumes is immunosuppressive through systemic, respiratory, and dermal routes of exposure in a murine model and raise concerns regarding the potential for adverse immunological effects.

  12. Mechanical properties of hot mix asphalt made with recycled aggregates from reclaimed construction and demolition debris

    Directory of Open Access Journals (Sweden)

    Taibo, J.

    2007-03-01

    Full Text Available The mix design for asphalt mixtures containing recycled aggregates from construction and demolition debris was evaluated. The tests conducted to characterize the mechanical behaviour of these mixtures showed that the mechanical properties of mixtures with recycled and virgin aggregate are similar. The asphalt mixtures containing recycled aggregate proved to have lower resistance to water action. Nonetheless, recycled aggregate was found to be potentially usable in asphalt mixtures if higher quality materials are selected and such low resistance is corrected. This will call for expanding upon the preliminary work described in the present article.En este trabajo se dosificaron mezclas bituminosas fabricadas con áridos reciclados de residuos de construcción y demolición. Se realizaron una serie de ensayos que permitieron caracterizar el comportamiento mecánico de estas mezclas. Los parámetros mecánicos de las mezclas con áridos reciclados son similares a los de las mezclas fabricadas únicamente con áridos naturales de cantera. Sin embargo, las mezclas bituminosas con áridos reciclados tuvieron un mal comportamiento frente a la disminución de la resistencia por pérdida de cohesión por la acción del agua. No obstante, mediante la selección de materiales de mejor calidad y corrección de este mal comportamiento, existen posibilidades de utilizar áridos reciclados en mezclas bituminosas. Para ello será necesario ampliar la primera aproximación realizada en este artículo.

  13. Sensitivity analysis of longitudinal cracking on asphalt pavement using MEPDG in permafrost region

    Directory of Open Access Journals (Sweden)

    Chen Zhang

    2015-02-01

    Full Text Available Longitudinal cracking is one of the most important distresses of asphalt pavement in permafrost regions. The sensitivity analysis of design parameters for asphalt pavement can be used to study the influence of every parameter on longitudinal cracking, which can help optimizing the design of the pavement structure. In this study, 20 test sections of Qinghai–Tibet Highway were selected to conduct the sensitivity analysis of longitudinal cracking on material parameter based on Mechanistic-Empirical Pavement Design Guide (MEPDG and single factorial sensitivity analysis method. Some computer aided engineering (CAE simulation techniques, such as the Latin hypercube sampling (LHS technique and the multiple regression analysis are used as auxiliary means. Finally, the sensitivity spectrum of material parameter on longitudinal cracking was established. The result shows the multiple regression analysis can be used to determine the remarkable influence factor more efficiently and to process the qualitative analysis when applying the MEPDG software in sensitivity analysis of longitudinal cracking in permafrost regions. The effect weights of the three parameters on longitudinal cracking in descending order are air void, effective binder content and PG grade. The influence of air void on top layer is bigger than that on middle layer and bottom layer. The influence of effective asphalt content on top layer is bigger than that on middle layer and bottom layer, and the influence of bottom layer is slightly bigger than middle layer. The accumulated value of longitudinal cracking on middle layer and bottom layer in the design life would begin to increase when the design temperature of PG grade increased.

  14. 基于微观结构的北美岩沥青改性机理研究∗%Study on the North American rock asphalt modified mechanism based on microstructure

    Institute of Scientific and Technical Information of China (English)

    黄文通; 徐国元; 刘宇; 王端宜

    2015-01-01

    采用软化点实验和动态剪切温度扫描实验分析了北美岩沥青改性沥青的高温性能;利用电子扫描电镜法、荧光显微镜法、差示扫描量热法、核磁共振波谱法,对不同掺量的北美岩沥青改性沥青进行微观结构的改性机理研究。结果表明,北美岩沥青有效提高沥青流变性能和热稳定性能,改善沥青抗车辙能力和耐老化能力。北美岩沥青增强沥青分子间作用力,提高沥青粘度,改善沥青温度敏感性。北美岩沥青对基质沥青存在物理改性和化学改性的双重改性作用。%The softening point test and dynamic shear temperature sweep test have been used to analyze high temperature performance of North American rock modified asphalt.Fluorescence microscopy,differential scan-ning calorimetry and nuclear magnetic resonance spectrum have been used to study modified asphalt microstruc-ture with various mixing amounts of the North American rock asphalt.The results suggest that the North A-merican rock asphalt can:(1 )increase the rheological performance and thermal stability of asphalt effectively, thereby improving the anti-rutting properties and the anti-aging properties of modified asphalt;(2)reinforce as-phalt intermolecular forces,improving viscosity and temperature sensitivity of modified asphalt;(3)the North American rock asphalt has a double modifying function on base asphalt,physically and chemically.

  15. Surface modification of basalt with silane coupling agent on asphalt mixture moisture damage

    Energy Technology Data Exchange (ETDEWEB)

    Min, Yahong; Fang, Ying; Huang, Xiaojun; Zhu, Yinhui; Li, Wensheng [College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Yuan, Jianmin [College of Materials Engineering, Hunan University, Changsha, 410082 (China); Tan, Ligang [College of Mechanical and Vehicle Engineering, Hunan University, Changsha, 410082 (China); Wang, Shuangyin [State Key Laboratory of Chem/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Wu, Zhenjun, E-mail: wooawt@163.com [College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China)

    2015-08-15

    Graphical abstract: - Highlights: • A new silane coupling agent was synthesized based on KH570. • Basalt surface was modified using the new silane coupling agent. • Chemical bond between basalt and the new silane coupling agent was formed. • Asphalt mixture which used modified basalt show superior water stability. - Abstract: A new silane coupling agent was synthesized based on γ-(methacryloyloxy) propyltrimethoxysilane (KH570). The surface of basalt rocks was modified by KH570 and the new silane coupling agent (NSCA), and the interfacial interaction between silane coupling agent and basalt was also studied. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis showed that the silane coupling agent molecule bound strongly with basalt rocks. Scanning electronic microscopy (SEM) observation showed that a thin layer of coupling agent was formed on the surface of modified basalt. The boiling test and immersion Marshall test confirmed that the moisture sensitivity of basalt modified with the new silane coupling agent increased more significantly than that untreated and treated with KH570. The Retained Marshall Strength of basalt modified with the new coupling agent increased from 71.74% to 87.79% compared with untreated basalt. The results indicated that the new silane coupling agent played an important role in improving the interfacial performance between basalt and asphalt.

  16. Sinopec Wins Bid for Special Asphalt for Racing Track

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ On February 13 Sinopec and Shanghai International Circuit held a signing ceremony in Beijing for the contract to supply special asphalt for racing track use. Mr. Wang Jiming,Vice Board Chairman and President of Sinopec and Mr. Wang Tianpu, Senior Vice President of Sinopec, attended the ceremony.

  17. The adoption of innovative asphalt equipment in road construction

    NARCIS (Netherlands)

    Habets, Thijs; Voordijk, Hans; Sijde, van der Peter

    2011-01-01

    Purpose – The purpose of this paper is to provide insight into the adoption process of innovative asphalt equipment in road construction and how the level of knowledge as characterised by the level of education in the companies affects this process. The emphasis is on equipment used for transporting

  18. Performance related characterisation of the mechanical behaviour of asphalt mixtures

    NARCIS (Netherlands)

    Molenaar, J.M.M.

    2004-01-01

    The investigation was undertaken to support innovations in the field of asphalt pavement design and material selection, and to be able to evaluate or judge the risk of failure and cost-effectiveness of newly developed paving materials in order to justify their application. To be able to determine th

  19. Optimal formulations of some asphalt concrete roadway protective impregnation compositions

    Directory of Open Access Journals (Sweden)

    Yulia A. Ubas’kina

    2016-03-01

    Full Text Available The current paper describes optimization of the formulations of asphalt concrete roadway protective impregnation compositions based on BND 60/90 bitumen modified with petroleum resin. Physicochemical, technological and operating parameters of the prepared samples of the compositions are investigated.

  20. Effects of Deicers on Properties of SMA and AC Asphalt Mixture%除冰盐对SMA与AC沥青混合料性能的影响

    Institute of Scientific and Technical Information of China (English)

    李明婷; 张晓可

    2016-01-01

    With the application of deicing salt in the asphalt pavement in northern China ,there are different forms of damage in asphalt pavement.The durability of asphalt pavement is reduced. In order to study the effects of the types of ice salt and the freeze -thaw cycles on the properties of SMA -13 and AC-13 asphalt mixture ,three tests are taken :indirect tensile fatigue test ,freeze-thaw split test and Kentucky flying test . The results indicate that :the scattering loss of the asphalt mixture ,strength ratio of freeze thaw split and fatigue life will be significantly reduced with deicing salt ’s erosion ,which sodium chloride deicing salt has greater impact on the low temperature cracking resistance of mixture and stability of water ;The effect of the addition of deicing salt on the performance of asphalt mixture can be reduced by us-ing SMA-13 asphalt mixture.%随着除冰盐在我国北方路面除冰养护领域的应用,沥青路面出现了开裂、沥青膜剥落、混合料松散等病害,导致其耐久性降低。针对除冰盐侵蚀破坏沥青路面问题,采用盐冻循环后的间接拉伸疲劳试验、冻融劈裂试验、肯塔堡飞散试验研究除冰盐种类、冻融循环次数对SMA -13、AC -13沥青混合料性能的影响。结果表明:在除冰盐的侵蚀下,抗疲劳性能下降,沥青混合料的冻融劈裂强度比降低,飞散损失率明显增大,其中氯化钠除冰盐对混合料的低温抗裂性、水稳定性影响更大。另外, SMA-13沥青混合料性能受除冰盐的影响较小。

  1. 长效型主动融雪沥青混合料路用性能试验%Experiment of Road Performance of Asphalt Mixture with Automatic Long-term Snowmelt Agent

    Institute of Scientific and Technical Information of China (English)

    李福普; 王志军

    2012-01-01

    为全面验证Mafilon材料置换矿粉后沥青混合料的路用性能,进行了室内试验并现场观测了该沥青混合料的融冰化雪能力.对比不同Mafilon掺量的沥青混合料的性能差异,结果表明:在相同矿料级配条件下,长效型主动融雪沥青混合料高温性能优良,Mafilon掺量对沥青混合料的低温性能基本没有影响.3种沥青混合料的水稳定性满足规范要求,但是水稳定性能随Mafilon掺量的增加而降低.从室内和试验路长效型主动融雪沥青混合料的除冰雪效果看,Mafilon置换矿粉比例越高,其除冰雪效果越明显.%The asphalt mixture with Mafilon which in lieu of mineral fines and helps to deice is automatic long-term snow-melt asphalt mixture. In order to prove the performance of asphalt mixture with Mafilon content, some indoor tests were conducted, the field deicing capacity of the asphalt mixture was observed, and the performance of several asphalt mixtures with different contents of Mafilon were compared. The results show that (1 ) with the same gradation, automatic long-term snow melting asphalt mixtures has better anti-rutting performance, and the content of Mafilon has little effect on the low temperature performance of asphalt mixture; (2) the moisture stability of three kinds of asphalt mixture can meet the requirement of the specification, but it would decrease with the increase of Mafilon content. According to the indoor and outdoor deicing effects of the subjected asphalt mixture, it is better to deice pavement with more Mafilon content in the asphalt mixture.

  2. Evaluation system for CO2 emission of hot asphalt mixture

    Directory of Open Access Journals (Sweden)

    Bo Peng

    2015-04-01

    Full Text Available The highway construction industry plays an important role in economic and development, but is also a primary source of carbon emission. Accordingly, with the global climate change, energy conservation and reduction of carbon emissions have become critical issues in the highway construction industry. However, to date, a model for the highway construction industry has not been established. Hence, to implement a low-carbon construction model for highways, this study divided asphalt pavement construction into aggregate stacking, aggregate supply, and other stages, and compiled a list of energy consumption investigation. An appropriate calculation model of CO2 emission was then built. Based on the carbon emission calculation model, the proportion of carbon emissions in each stage was analyzed. The analytic hierarchy process was used to establish the system of asphalt pavement construction with a judgment matrix, thereby enabling calculation of the weight coefficient of each link. In addition, the stages of aggregate heating, asphalt heating, and asphalt mixture mixing were defined as key stages of asphalt pavement construction. Carbon emissions at these stages accounted for approximately 90% of the total carbon emissions. Carbon emissions at each stage and their impact on the environment were quantified and compared. The energy saving construction schemes as well as the environmental and socioeconomic benefits were then proposed. Through these schemes, significant reductions in carbon emissions and costs can be achieved. The results indicate that carbon emissions reduce by 32.30% and 35.93%, whereas costs reduce by 18.58% and 6.03%. The proposed energy-saving and emission reduction scheme can provide a theoretical basis and technical support for the development of low-carbon highway construction.

  3. 沥青再生还原剂性能的研究%Study on Asphalt Regenerated Reductant Performance

    Institute of Scientific and Technical Information of China (English)

    屈春秀; 郝丽峰

    2014-01-01

    Sprayed with a certain amount of regenerated reductant in asphalt pavement can improve the pavement performance and prolong the service life of pavement.In order to maximize the effect of regenerated reductant,two kinds of regenerated reductant in improving regeneration performance of the aging asphalt has carried on the prelimina-ry study through a series of laboratory tests,then that different dosage of regenerated reductant effect regeneration performance of the aging asphalt is analysised.In order to achieve the best effect of regeneration,the article puts out that species of regenerated reductant should be selected according to scientific knowledge and the best dosage of regen-erated reductant should be determined according to the degree of aging of asphalt.%在沥青路面上喷洒一定量的再生还原剂,能够改善路面的路用性能,延长路面使用寿命。为了使再生还原剂发挥最大的效果,文章通过一系列的室内试验,对两种再生还原剂在改善老化沥青再生性能方面进行了初步研究,分析了再生还原剂在不同掺量的情况下对老化沥青再生性能的影响。文章提出了科学的选择再生还原剂的种类,根据沥青的老化程度合理确定再生还原剂的最佳用量,从而达到最佳的再生效果。

  4. Properties of Warm Mix-Recycled Modified Asphalt SMA Mixture%温拌—再生改性沥青SMA混合料性能研究

    Institute of Scientific and Technical Information of China (English)

    陈静云; 马强

    2012-01-01

    目的 研究温拌-再生改性沥青SMA混合料的路用性能和疲劳性能,为温拌-再生技术在工程中的应用提供有价值的数据和理论依据.方法 采用马歇尔配合比设计方法进行设计.对旧路沥青混合料和既添加再生剂又添加温拌剂的温拌-再生沥青混合料的各项性能指标进行对比研究.结果 确定了温拌-再生改性沥青SMA混合料的最佳拌合温度为140℃.温拌-再生改性沥青SMA混合料的动稳定度为7 450次/mm,残留稳定度为87.3%,冻融劈裂强度比为84.7%,都高于规范要求.在4种应力比下温拌-再生改性沥青SMA混合料的疲劳寿命都高于旧沥青混合料.结论 在降低拌合温度的情况下,温拌-再生沥青混合料的力学性能和路用性能可以满足规范要求.抗水损害和抗疲劳性能都得到了提高,冬季现场热再生施工期得到了延长.改性沥青SMA混合料的温拌-再生技术具有很广阔的应用前景.%The purpose of this paper is to find out the valuable data and theoretical basis for the application of warm mix-recycled technology on engineering according to the study of the pavement performance and fatigue property of warm mix-recycled modified asphalt SMA mixture. Marshall Test Design methods of asphalt mixtures are used to design the warm mix-recycled asphalt mixture. This paper offers a comparative study on each performance index of old pavement asphalt mixture and warm mix-recycled asphalt mixture both add regenerant and warm mix agent. As the result of that we determined the best mixing temperature of warm mix-recycled modified asphalt SMA mixture is 140 ℃. The dynamic stability is 7 450 times/mm,the residual stability is 87. 3% and the intensity ratio of frozen and melted is 84. 7%. Both of these indexes are all higher than standard requirements. The fatigue life of warm mix-recycled modified asphalt SMA mixture is higher than old asphalt mixture under four different stress ratios. The

  5. Influence of Subgrade and Unbound Granular Layers Stiffness on Fatigue Life of Hot Mix Asphalts - HMA

    Directory of Open Access Journals (Sweden)

    Hugo A. Rondón-Quintana

    2013-11-01

    Full Text Available The mainly factors studied to predict fatigue life of hot mix asphalt-HMA in flexible pavements are the loading effect, type of test, compaction methods, design parameters of HMA (e.g., particle size and size distribution curve, fine content, type of bitumen and the variables associated with the environment (mainly moisture, temperature, aging. This study evaluated through a computer simulation, the influence of the granular layers and subgrade on the fatigue life of asphalt layers in flexible pavement structures. Mechanics parameters of granular layers of subgrade, base and subbase were obtained using the mathematical equations currently used for this purpose in the world. The emphasis of the study was the city of Bogotá, where the average annual temperature is 14°C and soils predominantly clay, generally experience CBR magnitudes between 1% and 4%. General conclusion: stiffness of the granular layers and subgrade significantly affect the fatigue resistance of HMA mixtures. Likewise, the use of different equations reported in reference literature in order to characterize granular layers may vary the fatigue life between 4.6 and 48.5 times, varying the thickness of the pavement layers in the design.

  6. Performance of RAP in the System of Cold Inplace Recycling of Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    MA Baoguo; WANG Haifeng; WEI Dingbang

    2011-01-01

    The property of reclaimed asphalt pavement(RAP) mixture will be affected mainly by composition of old asphalt/soil and cement content in CIR system.We studied the relationship between A/S and cementitious materials.It showed that if there was no soil in RAP,the unconfined compressive strength was only from 0.18 MPa to 1.07 MPa even if adding cement was from 2% to 6%,and RAP samples collapsed during conserving in water.The optimum water content rose from 6.5% to 11% with the declining of A/S from S=0 to A/S=1/5.Five RAP samples all got the maximum compressive strength when A/S=5/5,and the maximum compressive strength of the samples adding 6% cement was 3.17 MPa.It showed that the capacity of RAP was not only affected by A/S,but also by the content of cement.The dynamic modulus of RAP will increase with the rise of loading frequency and decrease with the temperature rising.SEM test showed that C-S-H interlacing formed the netted structure,and it enwrapped the aggregate and improved the strength of RAP.

  7. Towards small scale use of asphalt as a fuel. An application of interest to developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Faber, J.

    2002-01-01

    This survey deals with the feasibility of the combustion of asphalt instead of firewood. On the seashores of the numerous islands of Indonesia, especially on those of south and southeast Sulawesi, mangrove forests are endangered by extensive logging, lately on an increasing scale by locals for whom firewood is the sole resource of energy. Urged by Yayasan-Sarna, an Indonesian non-governmental organisation of South East Sulawesi, the Dutch foundation Zephyr-Sama has prompted research on the feasibility to use asphalt from deposits on the island of Buton as a domestic fuel. This research was thought to possibly lead to the development of a porous plug stove, or to a stove in which carbonised bamboo containers filled with asphalt are used as fuel elements. This survey consists of a literature review and an overview of possible routes for controlled combustion of asphalt. Attention has been paid to the environmental effects of the combustion as well. The literature mainly shows side effects of combustion of asphalt, which provide some knowledge on the combustion process. No direct studies on the combustion of asphalt were found. To explore the bottlenecks of the combustion process, an asphalt candle was made, because the taper seemed an ideal capillary active carrier for fluid asphalt. However, this experimental candle did not bum, likely due to high viscosity at the base of the taper and clogging of carbonaceous residue at the liquid/gas interface of the taper. An increase of the porosity of asphalt gives a better chance for a propagating combustion. The pores may increase the diffusion rate of volatile components, thus increasing the combustion rate. However, if asphalt is heated it will melt and the fluid will block the pores. Its melting at a relatively low temperature is a big handicap of asphalt. To overcome this handicap, asphalt could be transported by capillary forces into the combustion zone and combust at solid/liquid/gas interfaces - like is happening in a

  8. Research on the Performance of New Reactive Asphalt Modifier%新型反应性沥青改性剂技术性能研究

    Institute of Scientific and Technical Information of China (English)

    曹晓娟

    2015-01-01

    RET 是美国杜邦公司研发的一种新型沥青化学改性剂,通过与沥青中的分子和官能团发生化学反应,从而达到改善沥青使用性能的效果。通过分析研究不同种类改性沥青的 Superpave 性能试验结果及老化前后的低温 PG 分级温度及质量损失,表明 RET 改性剂能够明显改善沥青的高温稳定性和低温抗裂性。%RET(Reactive Elastomeric Terpolymer) is a kind of chemical modifier that was developed by Dupont, it can react with asphalt molecules and functional groups to improve the functional performance of the asphalt. In this paper, Superpave performance test results, low temperature PG grading temperature and mass loss before and after aging of different types of modified asphalt were analyzed and researched. The results show that RET modifier can significantly improve asphalt high temperature stability and low temperature crack resistance.

  9. Photoactive roadways: Determination of CO, NO and VOC uptake coefficients and photolabile side product yields on TiO2 treated asphalt and concrete

    Science.gov (United States)

    Toro, C.; Jobson, B. T.; Haselbach, L.; Shen, S.; Chung, S. H.

    2016-08-01

    This work reports uptake coefficients and by-product yields of ozone precursors onto two photocatalytic paving materials (asphalt and concrete) treated with a commercial TiO2 surface application product. The experimental approach used a continuously stirred tank reactor (CSTR) and allowed for testing large samples with the same surface morphology encountered with real urban surfaces. The measured uptake coefficient (γgeo) and surface resistances are useful for parametrizing dry deposition velocities in air quality model evaluation of the impact of photoactive surfaces on urban air chemistry. At 46% relative humidity, the surface resistance to NO uptake was ∼1 s cm-1 for concrete and ∼2 s cm-1 for a freshly coated older roadway asphalt sample. HONO and NO2 were detected as side products from NO uptake to asphalt, with NO2 molar yields on the order of 20% and HONO molar yields ranging between 14 and 33%. For concrete samples, the NO2 molar yields increased with the increase of water vapor, ranging from 1% to 35% and HONO was not detected as a by-product. Uptake of monoaromatic VOCs to the asphalt sample set displayed a dependence on the compound vapor pressure, and was influenced by competitive adsorption from less volatile VOCs. Formaldehyde and acetaldehyde were detected as byproducts, with molar yields ranging from 5 to 32%.

  10. Lymphocyte DNA damage in Turkish asphalt workers detected by the comet assay.

    Science.gov (United States)

    Bacaksiz, Aysegul; Kayaalti, Zeliha; Soylemez, Esma; Tutkun, Engin; Soylemezoglu, Tulin

    2014-01-01

    Asphalt has a highly complex structure and it contains several organic compounds including polycyclic aromatic hydrocarbons and heterocyclic compounds. In this study, comet assay was used to detect the DNA damage in blood lymphocytes of 30 workers exposed to asphalt fumes and 30 nonexposed controls. This is the first report on Turkish asphalt workers' investigated DNA damage using the alkaline single cell gel electrophoresis (SCGE). The DNA damage was evaluated by the percentage of DNA in the comet tail (% tail DNA) for each cell. According to our results, workers exposed to asphalt fumes had higher DNA damage than the control group (p asphalt fumes caused a significant increase in DNA damage and the comet assay is a suitable method for determining DNA damage in asphalt workers.

  11. Influence of limestone fillers on combustion characteristics of asphalt mortar for pavements

    DEFF Research Database (Denmark)

    Ke, Wu; Kai, Zhu; Wu, Hao;

    2014-01-01

    Asphalt materials will be ignited and release significant toxic fumes within tunnel fires. Thus, combustion characteristics of asphalt materials used in road tunnel should be studied in order to limit such an adverse effect. In the present work we study the influence of limestone fillers...... on combustion characteristics of asphalt mortar by thermogravimetric and kinetic analysis. It is shown that the combustion of asphalt mortar is not just a linear superposition of asphalt and limestone. The limestone will increase the ignition point and the activation energy of the primary volatile release......, and will catalyze the char formation from the primary volatile release. Kinetic analysis shows that the primary volatile release stage of asphalt mortar combustion can be explained by a three-dimensional diffusion model, the secondary volatile release and char combustion stage can be explained by a model under...

  12. Decision of National and Provincial Highway Asphalt Pavement Structure Based on Value Engineering

    Directory of Open Access Journals (Sweden)

    Yingwei Ren

    2014-01-01

    Full Text Available It is important that decision of asphalt pavement structure requires overall considerations of the performance and financial investment. To have asphalt pavement structure fulfilling good reliability, the asphalt pavement structure decision was researched based on value engineering theory. According to the national and provincial highway investigation data in Shandong Province during the last decade, the asphalt pavement performance attenuation rules of traffic levels and asphalt layer thicknesses were developed, and then the road performance evaluation method was presented. In addition, the initial investments, the costs of road maintenance, and middle-scale repair in a period were analyzed. For the light traffic and medium traffic example, using the value engineering method, the pavement performance and costs of which thickness varies from 6 cm to 10 cm were calculated and compared. It was concluded that value engineering was an effective method in deciding the asphalt pavement structure.

  13. Application of Cold Mix Asphalt in the Repair of Rural Roads%冷拌沥青在乡村公路修补中的应用

    Institute of Scientific and Technical Information of China (English)

    阳娟; 石月晴; 张子仪

    2016-01-01

    本文分析了目前农村公路的发展以及维护现状,指出水泥混凝土和热拌沥青混凝土在公路修补中的不足,进而提出冷拌沥青混凝土用于农村公路的想法。通过设计沥青混合料试件进行试验,选取混合料的和易性、稳定性、初始强度和抗水损失性进行了实验探究,验证了冷拌沥青混合料满足农村公路修补的要求,且具有高稳定性和低耗能等优点,最后总结出冷拌沥青在农村公路修补的市场和前景。%This paper analyzes the current development of rural roads and the maintenance of the status quo, points out the shortage of cement concrete and hot mix asphalt concrete in the road repair, and then puts forward the idea of cold mix asphalt concrete for the rural highway. Through the design of asphalt mixture test specimens, the workability, stability, initial strength and water resistance of the mixture are tested, the results show that cold asphalt mixture can meet the requirements of rural road repair, and have the advantages of high stability and low energy consumption etc. And finally it sums up the market and prospects of cold mix asphalt in the repair of the rural roads.

  14. 蓄盐沥青混合料除冰雪性能研究%Research on Deicing Performance of Asphalt Mixture Containing Salt

    Institute of Scientific and Technical Information of China (English)

    谭忆秋; 孙嵘蓉; 郭猛; 钟勇; 周水文

    2013-01-01

    In order to effectively evaluate the deicing performance of asphalt mixture containing salt and find out the deicing mechanism and effect of asphalt mixture containing salt, firstly the road performance of asphalt mixture containing salt was studied, then the system for testing adhesion between ice and asphalt mixture was developed, and the extreme fracture tensile and damage interface level were proposed to assess the adhesion between asphalt mixture and ice. The effect of grading types and temperature on adhesion was also studied. The deicing mechanism of asphalt mixture containing salt was studied with the freezing point test. The deicing effect of asphalt mixture containing salt was verified by indoor test and outdoor actual project. The results show that asphalt mixture containing salt can effectively decrease the adhesion between ice and mixture and the extreme fracture tensile of mixture containing salt is 27. 8% lower than that of ordinary mixture at -5 ℃ ; the open gradation asphalt mixture has better adhesion with ice than the dense gradation, and the adhesion ability increases with the increase of the nominal maximum aggregate size, or the decrease of the temperature, and the interface level decreases with the decrease of temperature; the road performance and deicing performance of asphalt pavement containing salt are good.%为了有效评价沥青路面除冰雪性能、揭示蓄盐沥青混合料除冰雪机理及效果,首先对蓄盐沥青混合料的路用性能进行了研究;其次开发了冰膜与沥青混合料表面粘结力测试系统,提出采用极限破坏拉力和破坏界面等级综合评价混合料与冰的粘结能力,分析了级配类型、温度对粘结能力的影响;并设计了冰点试验方法,研究了蓄盐沥青混合料除冰雪机理;最后通过室内试验和室外实体工程对除冰雪效果进行了验证.结果表明:蓄盐沥青混合料能有效降低混合料与冰之间的粘结力,-5℃时蓄盐混

  15. Development of an innovative bio-binder using Asphalt-rubber technology

    OpenAIRE

    2013-01-01

    This research work evaluates several parameters that can affect Asphalt Rubber (AR) binder performance and applies the AR technology to the development of an innovative renewable bio-binder that can fully and cost-effectively replace asphaltic bitumen derived from petroleum in flexible pavement construction. The “Binder Accelerated Separator” method was used to divide the constituents of the Asphalt Rubber and bio-binder (residual binder and swelled rubber). The physical and chemi...

  16. INVESTIGATING EFFECTS OF AMINE BASED MODIFIER ON RECYCLED ASPHALT SHINGLES BLENDING

    OpenAIRE

    2014-01-01

    A laboratory study was conducted to investigate the effects of Amine based modifier on rheological characteristics of particle filled viscous medium such as asphalt binder in presence of Recycled Asphalt Shingles (RAS). In this study, virgin asphalt binder (PG 64-22), three different percentages (20, 30 and 40%) of tear-off shingles and modifiers; Rediset, Evotherm and Bio-binder were used. The tear-off shingles acquired from local reroofing company in Greensboro, North Carolina; were finely ...

  17. Engineering and Design: Use of Petroleum Contaminated Soil in Cold-Mix Asphalt Stabilized Base Course

    Science.gov (United States)

    2007-11-02

    and construction of mixtures using petroleum contaminated soil and similar hydrocarbon waste for cold -mix asphalt stabilized base course (ASB). This...also performed an analysis using the diesel contaminated soil as part of a cold mix asphalt mixture . The mixtures produced with and without contaminated...quality materials ( RAP and asphalt cement) and good mixture design, construction procedures, and quality control, a high quality base or intermediate

  18. TESTING AND ANALYSES OF CHAT AND ASPHALT-CONTAINING CHAT

    Science.gov (United States)

    Granular mine waste are generated from the extraction and beneficiation of lead/zinc minerals. The fine gravel waste, commonly known as chat, in the Tristate Mining District contains elevated levels of lead, zinc and cadmium which can result in potentially serious human health a...

  19. Development of asphaltic mix with waste products use

    Directory of Open Access Journals (Sweden)

    Pugin Konstantin Georgievich

    2014-07-01

    Full Text Available The trend of high growth of the vehicle fleet in Russia along with the positive impact on the socio-economic development of the country has a number of adverse consequences, one of which is the high accident rate on the roads. The paper considers modern way to provide the safe vehicles flow with the use of colored asphalt, which is a kind of hot asphalt and can have a variety of colors, which consists of coloring pigments. The conventional method of coloring the asphalt mix is produced by adding color rubble or pigmenting additives. The task, which was put forward, was the establishment of such road concrete mix, from which, without the use of primary materials and without increasing the consumption of bitumen, asphalt concrete road surfaces of acceptable strength could be obtained. As a pigment the dust of gas purification system of electrical furnace DSP - 60 of «Kamastal» plant, Perm, was used. The composition of the dust waste from the furnace consists of metal oxides and silicates. Dust-gas-cleaning is a fine powder with a high specific surface (1.2…2.5 thousand cm /g and bulk density of 3.7…4.2 g/cm . The powder color is dark brown. The density of the ready colored asphalt samples is 2.47...2.49 g/cm , and water saturation is 3.50…3.55 %. As a result of the research the diagrams of the dependence of road concrete mix’s water saturation from dust percentage and a diagram of dependence of concrete mixes’ durability from dust percentage at t = 20° and 50° C were built. After analyzing the obtained curves it can be concluded that the increase of the percentage of dust leads to increase of water saturation of road concrete mix and reduced strength. Thus, the developed asphalt concrete mix allows visually separating the lanes on the road, it has the relevant regulatory requirements durability and water resistance. This mixture corresponds to the type B mark III and can be used in regions I, II, and partly III of road-climatic zones

  20. Study of Water Stability of Different Asphalt Mixtures for Ultra-Thin Surfacing Layer%不同类型超薄层沥青混合料的水稳定性研究

    Institute of Scientific and Technical Information of China (English)

    苏忠高

    2016-01-01

    采用浸水车辙试验和冻融劈裂试验分别评价了Type-B(美国级配)、改良型SMA-10、OGFC-10这3种级配和SBS改性沥青、普通沥青+8%抗车辙剂和高黏弹沥青3种结合料组成的9种超薄层沥青混合料的水稳定性.试验结果表明:有5种超薄层沥青混合料,即Type-B SBS改性沥青混合料、改良型SMA-10 SBS改性沥青混合料、Type-B高黏弹沥青混合料、改良型SMA-10高黏弹沥青和OGFC-10高黏弹沥青混合料满足现有规范对水稳定性的要求,其中改良型SMA-10高黏弹沥青混合料的综合性能最优,其条件前后的车辙动稳定度不仅分别是其他8种混合料的2.0~4.5倍和2.0 ~4.7倍.推荐该混合料用于重要的城市主干道、高速公路或重交通道路路面的预防性养护或维修.%By performing immersion rutting test and freeze-thaw splitting test,the water stability of nine different asphalt mixtures for ultra-thin surfacing layer was studied.The said nine asphalt mixtures were made respectively by three gradations (namely Type-B with USA gradation,improved SMA-10 and OGFC-10) and with three binders (namely SBS modified asphalt,common asphalt + 8% anti-rutting agent and highly viscoelastic asphalt).The test results show that five types of asphalt mixture for ultra-thin surfacing layer (namely Type-B SBS modified asphalt mixture,improved SMA-10 SBS modified asphalt mixture,Type-B highly viscoelastic asphalt mixture,improved SMA-10 highly viscoelastic asphalt mixture and OGFC-10 highly viscoelastic asphalt mixture) meet China' s prevailing specification for water stability of asphalt mixtures.Among them the improved SMA-10 highly viscoelastic asphalt mixture demonstrated optimal general performance with both rut dynamic stability and the immersion rutting dynamic stability 2.0 ~ 4.5 times and 2.0 ~ 4.7 times that of other eight mixtures and is thus recommended for use in pavement protective maintenance or repair of key urban artery

  1. 粉胶比对冷补沥青混合料性能的影响%Influence of Filler-Bitumen Ratio on Cold Patch Asphalt Mixture Performance

    Institute of Scientific and Technical Information of China (English)

    雷宗建; 黄国威; 张争奇

    2013-01-01

    The asphalt mortar which composed of reasonable filler-bitumen ratio has important influence on performances of asphalt mixture.Because the existence of thinner and additive,the properties,the best filler-bitumen ratio range and composition of cold patch asphalt mortar are different from general asphalt mortar.In order to put forward reasonable filler-bitumen ratio range of cold patch asphalt mixture,test methods are proposed to study on the influence law of filler-bitumen ratio on cold patch asphalt mixture by analyzing the high temperature stability,the forming strength and water stability of cold patch asphalt mixture in different filler-bitumen ratio.The test results show that reasonable filler-bitumen ratio range can make the best performance of cold patch asphalt mixture.Considering all kinds of road performances and economical efficiency requirements,it is suggested that the appropriate filler-bitumen ratio range of cold patch asphalt mixture in Guangdong Province is 1.0~1.3.But this rang can be reduced in drought or cold areas.%合理粉胶比的沥青胶浆是影响沥青混合料性能的重要因素.由于稀释剂和添加剂的存在,冷补沥青胶浆的性质和组成均与一般沥青胶浆不同,最佳粉胶比范围也有所差异.为了提出冷补沥青混合料合理的粉胶比范围,采用室内试验方法,通过分析冷补沥青混合料在不同粉胶比下的高温稳定性、成型强度和水稳定性等路用性能,研究粉胶比对冷补沥青混合料性能的影响规律.试验结果表明,合理的粉胶比范围能取得最佳的冷补沥青混合料性能,综合考虑各种路用性能和经济性的要求,建议广东地区冷补沥青混合料的粉胶比范围宜为1.0~1.3,但干旱或寒冷地区可以适当降低.

  2. Construction Technology Essentials for Drainage layer of Asphalt Stabilized Crushed Stone%沥青稳定碎石排水层施工技术要点

    Institute of Scientific and Technical Information of China (English)

    郑木莲; 彭磊; 马海淋

    2012-01-01

    To reduce the early water damage of asphalt concrete pavement, it is necessary to set the asphalt treated permeable base in the pavement structure and improve the ability of ruling out free water in the internal road. Compared with the foreign porous asphalt mixture gradation, the graduation range which is suitable for China engineering is determined, and the engineering graduation of asphalt treated permeable based on the Hua-Xin Expressway is designed. By figuring out the mine material surface area and oil film thickness to estimate the asphalt-aggregate ratio, combined with the leak test analysis and using Marshall stability test, pore ratio, bulk volume density, the optimal asphalt-aggregate ratio is eventually determined. The target and construction proportion of asphalt treated permeable are determined by the analysis of its properties and combination of the engineering practice. According to the type of asphalt treated permeable and comparison with the conventional structure of the asphalt concrete pavement, loose paving coefficient and compaction technology which fit asphalt treated permeable are formulated. The rationality of mix proportion, construction technology and the key point of construction control are verified by the construction quality examination.%为减少沥青混凝土路面早期水损害,在路面结构中设置沥青稳定碎石排水层,提高排除进入路面结构内部自由水的能力.对比国外排水沥青混合料的级配,确定适合我国工程运用的级配范围,依托化新高速公路实体工程,设计出沥青稳定碎石的工程级配.通过矿料表面积与油膜厚度估算油石比,结合析漏试验,运用马歇尔试验稳定度、空隙率、毛体积密度等最终确定最佳油石比.分析沥青稳定碎石混合料的特性,结合工程实践,确定沥青稳定碎石的目标配合比和施工配合比.根据沥青稳定碎石排水层的结构形式,对比常规沥青混凝土路面结构,制定符合

  3. Effects of Fibre Additive on the High Temperature Property of Asphalt Binder

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Polyester fibre and floc xylogen fibre were used to prepare fibre-asphalt binder.An SHRP's dynamic shear rheometer (DSR) was employed to investigate the rheology charac teristics of fibre-asphalt binder, andthe flow resistance of binder was revealed by combining the rutting parameter, G * / sinδ.The results indicate that both kinds of fibres remarkably improved the high temperature pe~orrnance of asphalt binder.At the same time, the reinforcement mechanism of the fibres in the asphalt binder was also analyzed.

  4. Assessing Mechanical Properties of Hot Mix Asphalt with Wire Wool Fibers

    OpenAIRE

    Ahmed N. Bdour; Yahia Khalayleh; Aslam A. Al-Omari

    2015-01-01

    This paper investigates the potential application of wire wool in the modification of hot asphalt mixes (HMA). Wire wool material is widely available at local markets as a by-product of wire wool industry and as waste products from homes. For the purpose of this study, wire wool was cut into small pieces so that it can be placed in the asphalt mixes. Different percentages of wire wool were incorporated with the hot asphalt mixes (0.0%, 0.25%, and 0.5%) of the total weight of the asphalt binde...

  5. Influence of crumb rubber and digestion time on the asphalt rubber binders

    OpenAIRE

    Neto, Silvrano Adonias Dantas; De Farias, Márcio Muniz; Pais, Jorge C.; Pereira, Paulo A. A.; Sousa, Jorge B.

    2006-01-01

    This paper shows the results of a study about the mechanical behavior of dense graded asphalt-rubber hot mixes prepared with two different types of asphalt-rubber binders. These asphalt-rubber binders were obtained with penetration grade asphalt (AC 50/70) mixed with 21% and 25% of crumb rubber in weight. The rubber was recycled from unserviceable tires using the ambient grinding process. Hot mixes made with the conventional binder AC 50/70 were also studied for comparison. The...

  6. The Silurian Reservoir Bed-Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 王洪玉; 曾溅辉

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt) in the Silurian asphaltic sandstones of the Tarim Basin. These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir, which were derived from Lower Paleozoic source rocks. Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration. The differen tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed, and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil. There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin. One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the transport layer and unconformity surface. Reservoir bed-differentiated asphalts have two characteristics: total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity. The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  7. Optimization of technical measures for improving high-temperature performance of asphalt-rubber mixture

    Institute of Scientific and Technical Information of China (English)

    Chuan Xiao; Tianqing Ling; Yanjun Qiu

    2013-01-01

    Asphalt-rubber pavements often become dam-aged in high-temperature regions and appear rutted or wavy, and experience slippage. To improve the high-tem-perature performance of the asphalt-rubber mixture, tech-nical measurements, such as, the optimal adjustment of gradation, technique of composite modification, and con-trol of compaction were investigated. An optimal adjust-ment of aggregate gradation based on stone matrix asphalt improves the high-temperature stability of the asphalt-rubber mixture significantly. Through composite modifi-cation, the effect of asphalt-rubber modification was enhanced, and the dynamic stability and relative defor-mation indices of the asphalt-rubber mixture were improved significantly. Furthermore, compaction parame-ters had a significant influence on the high-temperature stability of the asphalt-rubber mixture. The rolling times for compacting the asphalt-rubber mixture should be controlled to within 18-20 round-trips at a molding tem-perature at 180 ?C;if the rolling time is a 12 round-trip, the compaction temperature of the asphalt-rubber mixture should be controlled between 180 and 190 ?C.

  8. The Silurian Reservoir Bed—Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 等

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt)in the Silurian asphaltic sandstones of the Tarim Basin.These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir,which were derived from Lower Paleozoic source rocks.Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration.The different-tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed,and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil.There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin.One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the trans-port layer and unconformity surface.Reservoir bed-differentiated asphalts have two characteris-tics:total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity.The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  9. An atomistic-based chemophysical environment for evaluating asphalt oxidation and antioxidants.

    Science.gov (United States)

    Pan, Tongyan; Sun, Lu; Yu, Qifeng

    2012-12-01

    Asphalt binders in service conditions are subject to oxidative aging that involves the reactions between oxygen molecules and the component species of bulk asphalt. As a result, significant alterations can occur to the desired physical and/or mechanical properties of asphalt. A common practice to alleviate asphalt aging has been to employ different chemical additives or modifiers as antioxidants. The current state of knowledge in asphalt oxidation and antioxidant evaluation is centered on determining the degradation of asphalt physical properties, mainly the viscosity and ductility. Such practices, although meeting direct engineering needs, do not contribute to the fundamental understanding of the aging and anti-oxidation mechanisms, and thereby developing anti-aging strategies. From this standpoint, this study was initiated to study the chemical and physical bases of asphalt oxidation, as well as the anti-oxidation mechanisms of bio-based antioxidants using the coniferyl-alcohol lignin as an example. A quantum chemistry (QC) based chemophysical environment is developed, in which the various chemical reactions between asphalt component species and oxygen, as well as the incurred physical changes are studied. X-ray photoelectron spectroscopy (XPS) was used to validate the modified and unmodified asphalt models.

  10. Effect of ageing on rheological properties of storage-stable SBS/sulfur-modified asphalts.

    Science.gov (United States)

    Zhang, Feng; Yu, Jianying; Wu, Shaopeng

    2010-10-15

    Oxidative ageing as an inevitable process in practical road paving has a great effect on the properties of polymer-modified asphalts (PMAs). In this article, the effect of short-term and long-term oxidative ageing on the rheological, physical properties and the morphology of the styrene-butadiene-styrene (SBS)- and storage-stable SBS/sulfur-modified asphalts was studied, respectively. The analysis on the rheological and physical properties of the PMAs before and after ageing showed the two major effects of ageing. On one hand, ageing prompted the degradation of polymer and increased the viscous behaviour of the modified binders, on the other, ageing changed the asphalt compositions and improved the elastic behaviour of the modified binders. The final performance of the aged binders depended on the combined effect. After ageing, the storage-stable SBS/sulfur-modified asphalts showed an obvious viscous behaviour compare with the SBS-modified asphalts and this led to an improved low-temperature creep property. The rutting resistance of the SBS-modified asphalts declined by the addition of sulfur due to the structural instability of the SBS/sulfur-modified asphalts. The rheological properties of the modified binders before and after ageing also depended strongly on the structural characteristics of SBS. The observation by using optical microscopy showed the compatibility between asphalt and SBS was improved with further ageing, especially for the storage-stable SBS/sulfur-modified asphalts.

  11. The Effect of Thermal Stress on Asphalt Workers’ Function and Their Physiological Parameters

    OpenAIRE

    RAMAZAN MIRZAEI; ROOHALAH HAJIZADEH; KEYKAOUS AZRAH; MOHAMMADHOSEIN BEHESHTI

    2015-01-01

    Heat stress effects on physical and mental health of workers and decreases human function. Asphalt workers are both exposed to the heat of their working process and to the sun heat. This study aimed at evaluating thermal stress and its following function fall and the effect of asphalt work on the degree of heat stress and asphalt workers’ physiological parameters. The present study was done at the work location of 29 asphalt workers in Qum City,  central  Iran.  The  degree  of  thermal stres...

  12. ENHANCING ASPHALT RHEOLOGICAL BEHAVIOR AND AGING SUSCEPTIBILITY USING BIO-CHAR AND NANO-CLAY

    OpenAIRE

    2014-01-01

    The life expectancy of Asphalt Binder (AB) has been negatively impacted by the harsh bombardment of UV rays. UV rays cause asphalt to oxidize faster, which results in deterioration of asphalt rheological characteristics that can lead to pavement distresses. This study investigates the impact of bio-char and nano-clay of asphalt rheological properties. Two nano scale materials were used for this study were nano-clay and bio-char. Nano-clay (Cloisite 30B) is a naturally occurring inorganic mine...

  13. Evaluation of rheological and thermic properties of neat and modified asphalt with a waste of LDPE

    Directory of Open Access Journals (Sweden)

    William Andrés Castro López

    2016-01-01

    Full Text Available Context: The asphalt technology and modified asphalt mixtures has been widely used and studied, worldwide. Adding polymers to asphalt modifies mechanical, chemical and rheological properties, trying to improve behavior of the mixtures subjected to different environmental and load conditions. The paper report results from rheological and thermal characterization on conventional 60-70 asphalt cement and 60-70 asphalt cement modified by introducing a waste of low density polyethylene (LDPE. Method: Modification of the asphalt was performed by wet way in a proportion of LDPE/CA=5% with respect to the mass. Rheological (using DSR, Thermogravimetry (TGA and Differential Scanning Calorimetry (DSC techniques were performed. Results and Conclusions: The modified asphalt develops a remarkable increase in stiffness and improvement of the performance grade at high temperatures of service. Additionally, the modified asphalt is more resistant to oxidation and aging processes due to heat. However, the asphalt modified showed a decrease in crack resistance at low and intermediate temperatures of service.

  14. 老化对 PE改性沥青混合料高温性能的影响%Influence of Different Aging State on the Performance of PE Modified Asphalt Mixture at High-Temperature

    Institute of Scientific and Technical Information of China (English)

    宋玉珠

    2014-01-01

    Taking AH-70 asphalt as base asphalt,the modified asphalt mixture was prepared by polyethylene (PE ),The high temperature performance of PE modified asphalt mixture were studied according to wheel rutting test,the static creep test and dynamic creep test,in this study,the influence of aging on the dynamic stability,stiffness modulus, permanent deformation and flow number were researched.The results show that the high temperature performance of PE modified asphalt mixture were improved when aged.Rutting test reflects the deformation of asphalt mixture focused on the short term aging stage,and the aging influenced the stiffness modulus,and flow number,while decreased the perma-nent deformation.%以 AH-70沥青为基质沥青,选用 PE 为改性剂制备改性沥青混合料,考察了老化对 PE 改性沥青混合料高温性能的影响,并采用了车辙试验、静态蠕变试验和动态蠕变试验,分析了老化对 PE 改性沥青混合料动稳定度、劲度模量、永久变形量及流变次数的影响。试验结果表明,PE 改性沥青混合料在老化后,其高温稳定性得到了提高,车辙试验反映沥青混合料的变形主要集中在短期老化阶段。老化后的沥青混合料劲度模量增大,其永久变形量降低、流变次数增大。

  15. Effect of Functional Chemical Admixtures on the Performance of Cement Asphalt Mortar Used in Ballastless Track

    Institute of Scientific and Technical Information of China (English)

    JIANG Jinyang; SHE Wei; LI Wei; PAN Li

    2015-01-01

    Chemical admixtures are of paramount importance to the performance of modern cement based composites. In this paper, we performed a series of tests to investigate the effects of chemical admixtures on the cement asphalt mortar (CA mortar), i e, compressive strength, frost resistance, permeability, fatigue resistance, pore structure and microstructure. In particular, two types of chemical admixtures were tested,i e, defoamer (tributyl phosphate (TBP)) and polycarboxylate superplasticizer (PS). The results indicate that the addition of TBP and PS eliminates big bubbles and promotes small non-connected pores forming in matrix. Besides, an optimum dosage of TBP and PS may be determined with respect to the frost resistance, permeability and fatigue resistance of CA mortar. Further elaborative discussions are presented as well as experimental evidences from mercury intrusion porosimetry, scanning electron microscopy and energy dispersive spectroscopy.

  16. Key influential factors of fatigue and self-healing properties of asphalt mixture%沥青混合料疲劳自愈性能关键影响因素

    Institute of Scientific and Technical Information of China (English)

    杨军; 王昊鹏; 廖辉

    2016-01-01

    为了研究不同沥青混合料疲劳自愈性能影响因素的显著水平,进行了有休息期和无休息期的沥青混合料室内四点弯曲疲劳试验。通过定义愈合指数,对不同因素条件下的沥青混合料疲劳试验结果进行灰关联分析,分别研究了沥青种类、沥青含量、空隙率、温度、休息期、损伤程度对沥青混合料疲劳自愈性能的影响程度。结果表明,基于愈合指数可得到即时的沥青混合料自愈合率,而无需等待疲劳试验结束。沥青种类对沥青混合料自愈合能力的影响最显著;休息期和损伤程度与沥青混合料的自愈合能力关联显著,其影响仅次于沥青种类;空隙率、温度、沥青用量则影响不显著。在工程实践中,可通过合理选择沥青种类、控制交通流量等方式提高沥青路面自愈合性能。%In order to investigate the significance level of different factors which influence the fatigue and self-healing properties of asphalt mixture, indoor four-point bending fatigue tests with and with-out rest periods were conducted.Through defining the healing index, the fatigue results of asphalt mixture with different influential factors were studied by grey relational analysis.The influence de-grees of the asphalt type, asphalt content, air voids, temperature, rest period, and damage degree on the fatigue and self-healing properties of asphalt mixture were studied, respectively.The results show that according to the defined healing index, the real-time self-healing rate of asphalt mixture can be obtained without finishing fatigue tests.The influences of the asphalt type on the self-healing capacity of asphalt mixture is the most significant.The rest period and the damage degree have a sig-nificant correlation with self-healing capacity of asphalt mixture, and their influences follow that of the asphalt type.The influences of the air voids, temperature and asphalt content are not significant

  17. Research on Influencing Factors on Asphalt Mixture Shear Strength%沥青混合料抗剪强度影响因素研究

    Institute of Scientific and Technical Information of China (English)

    高燕希; 曾红雄; 张东省

    2009-01-01

    针对沥青路面抗剪强度不足而容易导致推移、拥包、车辙等早期病害的现象,基于沥青路面弹性层状理论,通过有限元建立符合实际受力的贯入模型;由单轴贯入试验分别得到不同级配、相同级配有无填加矿粉、不同油石比、不同沥青种类、不同集料类型沥青混合料的最大剪应力并分别结合1组相应的无侧限抗压强度进而计算出材料的c、φ值.通过数据分析后,初步总结出影响沥青混合料抗剪强度变化的一般规律.%To cope with the lower shear strength of asphalt pavement leading to early diseases such as slippage, upheaval and rutting, based on asphah pavement layered elastic theory, the penetration model in line with the actual forcing was established through finite element method. The maximum shear stresses of asphalt mixture with different gradations, same gradation with/without filled mineral fines, different asphalt contents, different asphalt types and different aggregate types were obtained from uniaxial penetration test, then c and φ values of these materials were calculated respectively with a group of corresponding unconfined compressive strength. Through data analysis, the regularity of impact on asphalt mixture shear strength was summed up initially.

  18. Evaluation of asphalt enhanced with locally made nanomaterials

    Directory of Open Access Journals (Sweden)

    HELAL EZZAT

    2016-08-01

    Full Text Available This research work focused on the investigation of the properties of asphalt binder modified with different percentages of nanoclay (NC and nanosilica. The nanosilica was manufactured from two different sources: silica fume (NSF and rice husk (NSH. Results showed that NSF tends to decrease the penetration and increase the softening point temperature (SFT and rotational viscosity (RV. However, NC content more than 3% was found to increase the penetration and decrease both RV and SFT. Using smaller percentages of NC increased both SFT and RV and decreased the penetration. Up to 3% of NSH exhibited improvement in penetration, SFT, and RV, however slight or no improvement was observed at higher contents. The Dynamic Shear Rheometer (DSR results showed obvious improvement in the Superpave performance grade. Both NSF and NC were found to improve Marshall stability of the asphalt mixtures.

  19. Integrated coke, asphalt and jet fuel production process and apparatus

    Science.gov (United States)

    Shang, Jer Y.

    1991-01-01

    A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

  20. New method to quantitatively evaluate the homogeneity of asphalt mixtures

    Institute of Scientific and Technical Information of China (English)

    WU Wen-liang; ZHANG Xiao-ning; WANG Duan-yi; LI Zhi

    2009-01-01

    To evaluate the homogeneity of asphalt mixtures, the images of sections obtained by cutting the as-phah mixtures specimen horizontally or vertically were analyzed with digital image processing techniques, and the particle area ratio was achieved by applying sector scan for horizontal specimen and vertical scan for vertical one. The research result indicates that the influence of random distribution of aggregates in cutting the specimen can be eliminated by using colored aggregates to distinguish coarse and fine aggregates and using color threshold to segment the images. Choosing three typical gradations, proving particle area ratio obeying normal distribution and using the variability of particle area ratio as an index, it is feasible to quantitatively evaluate the homogenei-ty of asphalt mixtures.

  1. Evidence of Multi-Stage Hydrocarbon Charging and Biodegradation of the Silurian Asphaltic Sandstones in the Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    刘洛夫

    2002-01-01

    Asphalts distributed widely in the Silurian sandstones of the Tarim Basin include dry asphalt, soft asphalt and heavy oil. These asphaltic sandstones underwent multi-episodic sedimentary and tectonic events, and their occurrence is diverse and complex, being mixed with normal oil usually. So far, very little work has been done on the asphaltic sandstone origin and hydrocarbon charging ages. After detailed study on the Silurian sandstones, the following highlights were obtained from the analytical results: distribution of the mixed asphalt, heavy oil and normal oil in the Silurian sandstones is the result of multi-stage hydrocarbon charging from the Lower Paleozoic marine source rocks; the characters of asphalts formed from oils of different charging ages are of difference; the most important process constraining.the asphaltic sandstone origin is thought to be biodegradation.

  2. Possibilities of preparation asphalt concrete by oil sands of Kazakhstan

    OpenAIRE

    Erbol Tileuberdi; Yerdos Ongarbayev; F. Behrendt; Schneider, I.; Yerzhan Imanbayev; B. Tuleutayev; Yerlan Doszhanov; Zulkhair Mansurov

    2012-01-01

    In the paper physicochemical properties of oil sands of Munayli-Mola deposits and efficient ways to use them for preparing asphalt concrete were represented. For determination of organic part of oil sands the extraction methods were used in Soxhlet apparatus by variety of solvents. It has been established 16 wt.% content of natural bitumen in oil sands, which compared with results of ash content determination. According to results of experiment, the natural bitumen is heavy oil and its charac...

  3. Structural Design of Asphalt Pavement for Low Cost Rural Roads

    Institute of Scientific and Technical Information of China (English)

    Yuan Goulin; Chen Rongshen

    2006-01-01

    On the basis of the equivalent axle load action frequency, the traffic classifications of rural roads as well as their corresponding types are classified. The asphalt pavement structure, road surface types and thickness of the rural roads are suggested for the various action frequency of the equivalent axle load. Furthermore, the roadbase thickness graphs are provided according to different equivalent axle load action frequency with different roadbed modulus and road surface modulus taken into account.

  4. The Research on the Cracks of the Asphalt Pavement

    Directory of Open Access Journals (Sweden)

    OuYangZiqiang

    2015-07-01

    Full Text Available The cracking is one of the common diseases of the asphalt pavement. According to the shape and the forming reasons, the cracks can be divided into two categories. Each categories can be divided into several types. Through the comparison and the analysis of the causes of different cracks, the prevention and the treatments are proposed in the respects of the structural design, material design and construction

  5. Physical and chemical characterization of asphalt (bitumen) paving exposures.

    Science.gov (United States)

    Herrick, Robert F; McClean, Michael D; Meeker, John D; Zwack, Leonard; Hanley, Kevin

    2007-01-01

    The purpose of this research was to characterize the physical and chemical properties of asphalt (bitumen) fume and vapor in hot mix asphalt roadway paving operations. Area and personal air samples were taken using real-time equipment and extractive sampling and analytical methods to determine worker asphalt exposure, as well as to characterize the properties of the particulate and vapor phase components. Analysis of personal inhalation and dermal samples by gas chromatography/mass spectroscopy showed that the polycyclic aromatic hydrocarbon profile is dominated by compounds with molecular weights below 228, and that substituted and heterocyclic polycyclic aromatic hydrocarbons comprised approximately 71% of the detectable mass concentration (vapor and particulate combined). Principal components analysis shows that the polycyclic aromatic hydrocarbons with molecular weights greater than 190 are the driving force behind the polycyclic aromatic compound exposures measured for the dermal and particulate phases; there was no clear trend for the vapor phase Most of the aerosol particles are fine (mass median aerodynamic diameter 1.02 microm; count median diameter 0.24 microm).

  6. 泡沫沥青发泡特性及其冷再生混合料性能研究%Research on Foaming Characteristics of Foam Asphalt and Performance of its Cold Recycled Mixture

    Institute of Scientific and Technical Information of China (English)

    奎永才; 卢章天

    2015-01-01

    选择3种沥青,采用沥青发泡试验就沥青品种、温度及发泡用水量对发泡效果的影响进行研究,并通过无侧限抗压强度试验、间接拉伸试验以及浸水马歇尔试验、冻融劈裂试验对沥青用量和RAP(沥青路面回收旧料)掺量对泡沫沥青冷再生混合料力学性能和水稳定性的影响进行研究. 结果表明:在所选3种沥青中,相同条件下中海70 #沥青的发泡效果最好,其最佳发泡温度约为160 ℃,最佳发泡用水量为2%;RAP掺量增加对混合料水稳定性能不利;随着RAP掺量增加,混合料无侧限抗压强度和间接拉伸强度逐渐降低;RAP掺量可达70%以上,但应严格控制.%This paper studies influences of varieties of asphalt, temperature and water consumption for foaming on foaming effect by selecting 3 kinds of asphalt and by means of asphalt foaming test, and studies influences of asphalt dosage and mixing amount of RAP ( reclaimed asphalt pavement ) on mechanical properties and water stability of cold recycling mixture of foaming asphalt via unconfined compressive strength test, indirect tensile test and immersion Marshall test and freeze-thaw split test. The results show that among the selected 3 kinds of asphalt, the foaming effect of Zhonghai No. 70 asphalt under the same conditions is the best, its optimal foaming temperature is approximate 160℃, and the best forming water consumption is 2%;increase of RAP mixing amount is adverse to water stability of mixture;with increase of RAP mixing amount, the unconfined compressive strength and indirect tensile strength of mixture decrease gradually;the RAP mixing amount can be up to 70%, but should be strictly controlled.

  7. Application of a bio-binder as a rejuvenator for wet processed asphalt shingles in pavement construction

    OpenAIRE

    2015-01-01

    This paper investigates the merits of application of bio-binder to enhance rheological properties of asphalt binder in the presence of wet processed recycled asphalt shingles (RAS). It will further examine the performance and workability of asphalt designed with and without a specified percentage of a bio-binder produced from swine manure and RAS. Bio-binder was introduced to liquid asphalt binder modified with four different percentages of RAS; the high and low temperature properties of each...

  8. Analysis of the Strength Influence Factors of Emulsified Asphalt Cold Recycled Mixtures%乳化沥青冷再生混合料强度影响因素分析

    Institute of Scientific and Technical Information of China (English)

    幸建升; 白丛启

    2013-01-01

    In order to study the strength influence factors of the emulsified asphalt cold recycled mixture, the author aggre-gates by changing the thickness proportion of mixed, emulsify-ied asphalt dosage, compaction work, cement dosage to emuls-ified the split ing strength test of asphalt cold recycled mixture line.%为了研究乳化沥青冷再生混合料的强度影响因素,我们通过改变粗细集料掺入比例、乳化沥青用量,击实功、水泥用量等来对乳化沥青冷再生混合料行劈裂强度试。

  9. Emissions Reductions Associated with the Use of Warm-Mix Asphalt as Compared to Hot-Mix Asphalt

    Science.gov (United States)

    2014-06-01

    processes generating greenhouse gases. The motivation was to meet strict emissions regulations set forth by the Kyoto Protocol (Prowell et al. 2012...estimating emissions during asphalt production, current protocols to measure and control emissions, and case studies where WMA emissions were measured and...Research Program (NCHRP) funded project 9-47a to update the Protocol for Documenting Emissions and Energy Reductions of WMA and Conventional HMA

  10. 77 FR 50651 - Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Hot Mix Asphalt Plants

    Science.gov (United States)

    2012-08-22

    ... Mix Asphalt Plants AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: EPA... Hampshire Hot Mix Asphalt Plant Rule at Env-A 2703.02(a). This rule establishes and requires limitations on visible emissions from all hot mix asphalt plants. This revision is consistent with the maintenance of...

  11. 77 FR 50608 - Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Hot Mix Asphalt Plants

    Science.gov (United States)

    2012-08-22

    ... Mix Asphalt Plants AGENCY: Environmental Protection Agency (EPA). ACTION: Direct final rule. SUMMARY... 2703.02 for hot mix asphalt plants. This rule establishes and requires limitations on visible emissions from all hot mix asphalt plants. This revision is consistent with the maintenance of all...

  12. Evaluation on High-temperature Adhesion Performance of Hot-applied Sealant for Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    LI Feng; LI Tinggang; SHI Xiaopei

    2014-01-01

    In order to investigate the high-temperature performances of the asphalt pavement hot-applied sealant, as well as to reduce failures of the sealant pullout, the softening point test and the flow test (two existing methods for evaluating high-temperature performances) were conducted. It was found that both tests could not accurately reflect the adhesion performances of the sealant at high temperatures. For this purpose, the adhesion test for PSAT (pressure sensitive adhesive tape) has been taken as a reference to develop a device that is suitable for evaluating the adhesion performances, by modifying relevant test parameters according to the road conditions at high temperatures. Thirteen common sealants were tested in the modified adhesion test, softening point test and flow test. The experimental results show that no significant correlation (p>0.05) exists between the adhesion value, softening point, adhesion value and flow value;while a significant correlation (p<0.05) exists between the softening point and flow value. The modified adhesion test is efficient in distinguishing the high-temperature adhesion performances of different sealants, and can be used as a standard method for evaluating such performances.

  13. Laboratory Investigation of Fatigue Characteristics of Asphalt Mixtures with Steel Slag Aggregates

    Directory of Open Access Journals (Sweden)

    Hassan Ziari

    2015-01-01

    Full Text Available There are many steel-manufacturing factories in Iran. All of their byproducts, steel slag, are dumped randomly in open areas, causing many environmentally hazardous problems. This research is intended to study the effectiveness of using steel slag aggregate (SSA in improving the engineering properties, especially fatigue life of Asphalt Concrete (AC produced with steel slag. The research started by evaluating the physical properties of the steel slag aggregate. Then the 13 types of mixes which contain steel slag in portion of fine aggregates or in portion of coarse aggregates or in all portions of aggregates were tested. The effectiveness of the SSA was judged by the improvement in Marshall stability, indirect tensile strength, resilient modulus, and fatigue life of the AC samples. It was found that replacing the 50% of the limestone coarse or fine aggregate by SSA improved the mechanical properties of the AC mixes.

  14. USING OF SBS TYPE POLYMERS AS ADDITIVE IN HOT MIX ASPHALT

    OpenAIRE

    NAMLI, Remzi

    2011-01-01

    Bitumen quality is the one of the major important factor which the achievement of asphalt mixtures. Using pore bitumen results in adequate performance from asphalt mixture. To improve the bitumen properties, additive materials are used. In this study, using of SBS type polymers as additive material in bitumen is researched. It is seen that using SBS effects bitumen positively in many aspects.

  15. Monitoring Hot Mix Asphalt Temperature to Improve Homogeneity and Pavement Quality

    NARCIS (Netherlands)

    Huerne, ter H.L.; Doree, A.G.; Miller, S.R.; Santagata, E.

    2009-01-01

    This paper describes how controlled compaction practices lead to better quality asphalt. Therefore, it is important that during compaction operations the mixture is at a suitable temperature in order to achieve the specified degree of compaction. The University of Twente’s Asphalt Paving Research an

  16. Reintroducing the intrinsic self-healing properties in reclaimed asphalt by rejuvenation

    NARCIS (Netherlands)

    Qiu, J.; Schlangen, H.E.J.G.; Van de Ven, M.F.C.; Shirazi, M.

    2013-01-01

    Reclaimed Asphalt (RA) is one of the largest fractions of raw materials used in road construction today. Probably over 90% of the total RA in the Netherlands is being reused in new asphalt constructions. RA contains aggregates coated with very hard bitumen (penetration grade of 10-20). During servic

  17. Damage detection and artificial healing of asphalt concrete after trafficking with a load simulator

    Science.gov (United States)

    Bueno, M.; Arraigada, M.; Partl, M. N.

    2016-08-01

    Artificial healing of asphalt concrete by induction heating requires the addition of electrically conductive and/or magnetic materials into the asphalt mixture. Hence, bitumen can be heated up by an alternating electromagnetic field, decreasing therefore its viscosity and allowing it to flow for closing cracks and recover bonding among the mineral aggregates.

  18. Asphalt Pavement Aging and Temperature Dependent Properties Using Functionally Graded Viscoelastic Model

    Science.gov (United States)

    Dave, Eshan V.

    2009-01-01

    Asphalt concrete pavements are inherently graded viscoelastic structures. Oxidative aging of asphalt binder and temperature cycling due to climatic conditions being the major cause of non-homogeneity. Current pavement analysis and simulation procedures dwell on the use of layered approach to account for these non-homogeneities. The conventional…

  19. Experimental Investigation of the Matching Relationship between Asphalt Particle and Reservoir Pore in Profile Control Process

    Directory of Open Access Journals (Sweden)

    Chengfeng Ren

    2016-01-01

    Full Text Available Modified sulfonated asphalt particles have a bright application prospect of the profile control of thick reservoirs due to the low cost, extensive sources, and good compatibility with reservoir. Nevertheless, the matching relationship between asphalt particles and reservoir pore has seldom been investigated till now. Oversized particles always block the near-wellbore area, which causes high injection pressures, while undersized particles cannot plug large pores. We designed a core for this experiment which has a high permeability zone in front of it and many pressure measuring points. We could quantitatively assess the matching relationship by measuring the on-way resistance coefficient, residual resistance factor, and relative change of permeability of man-made cores after injecting asphalt. Experimental results indicate that asphalt particles with sizes of 0.02 mm, 0.02–0.06 mm, and 0.08–0.1 mm match with reservoir permeability of 500 mD, 1000 mD, and 2000 mD, respectively. Undersized or oversized particles can reduce the conformance control effect, and the concentration of asphalt particles in the injectant can limit their migration ability. When the concentration of asphalt particles increases to 3000 mg/L, accumulations of asphalt particles can be caused in the formation, in which a scheme with asphalt particles alternative water injection is proposed to avoid the accumulation.

  20. Preparation and characterization of epoxy asphalt binder for pavement of steel deck bridge%钢箱梁桥铺装用环氧沥青材料制备和表征

    Institute of Scientific and Technical Information of China (English)

    陈志明; 亢阳; 闵召辉; 黄卫

    2006-01-01

    制备两组分的热固性环氧沥青,其中一个组分是顺酐化沥青、环氧树脂的固化剂和促进剂,另外一个组分是环氧树脂.分别使用Brookfild粘度计、拉伸实验和MTS研究了沥青的铺装适用性和混凝土性能.结果表明:尽管加入的顺酐仅有50%~60%与基础沥青发生了反应,但是与未对沥青进行顺酐化比较,其固化速率、断裂延伸率和抗拉强度等都有显著的提高.4%顺酐改性的沥青和固化剂结合与环氧树脂固化后具有平均断裂延伸率281.9%,平均强度2.63 MPa,固化混凝土的Marshell稳定度37.0 kN,未固化混凝土的Marshell稳定度10.2 kN,耐疲劳实验1 200万次试件无破坏.%A kind of thermosetting asphalt binder designated as epoxy asphalt, which is composed of two components: maleated asphalt with curing agents and accelerant of epoxy resin and epoxy resin, was prepared.Its paving feasibility and concrete performances were investigated using Brookfield viscosimeter, direct tensile test (DTT), Marshall testing and the MTS 810 hydraulic servos-system, respectively. Although only 50% to 60% of added maleic anhydride (MAH) reacted with the base asphalt irreversibly (probably by Diels-Alder mechanism), the curing rate, rupture elongation and tensile strength of maleated epoxy asphalt were enhanced more evidently than those of unmaleated epoxy asphalt. As a result, an epoxy asphalt made from 4% MAH modified asphalt and other curing agents was featured to have an average rupture elongation of 281.9%, an average tensile strength of 2. 63 MPa, and the Marshall stability of its cured concrete reached 37.0 kN, while that of uncured concrete was 10. 2 kN and the combined beam of fatigue test was still found to behave well after 12 × 106 cycles load.

  1. Airborne Exposures to Polycyclic Aromatic Compounds Among Workers in Asphalt Roofing Manufacturing Facilities.

    Science.gov (United States)

    Trumbore, David C; Osborn, Linda V; Johnson, Kathleen A; Fayerweather, William E

    2015-01-01

    We studied exposure of 151 workers to polycyclic aromatic compounds and asphalt emissions during the manufacturing of asphalt roofing products-including 64 workers from 10 asphalt plants producing oxidized, straight-run, cutback, and wax- or polymer-modified asphalts, and 87 workers from 11 roofing plants producing asphalt shingles and granulated roll roofing. The facilities were located throughout the United States and used asphalt from many refiners and crude oils. This article helps fill a gap in exposure data for asphalt roofing manufacturing workers by using a fluorescence technique that targets biologically active 4-6 ring polycyclic aromatic compounds and is strongly correlated with carcinogenic activity in animal studies. Worker exposures to polycyclic aromatic compounds were compared between manufacturing plants, at different temperatures and using different raw materials, and to important external benchmarks. High levels of fine limestone particulate in the plant air during roofing manufacturing increased polycyclic aromatic compound exposure, resulting in the hypothesis that the particulate brought adsorbed polycyclic aromatic compounds to the worker breathing zone. Elevated asphalt temperatures increased exposures during the pouring of asphalt. Co-exposures in these workplaces which act as confounders for both the measurement of total organic matter and fluorescence were detected and their influence discussed. Exposures to polycyclic aromatic compounds in asphalt roofing manufacturing facilities were lower than or similar to those reported in hot-mix paving application studies, and much below those reported in studies of hot application of built-up roofing asphalt. These relatively low exposures in manufacturing are primarily attributed to air emission controls in the facilities, and the relatively moderate temperatures, compared to built-up roofing, used in these facilities for oxidized asphalt. The exposure to polycyclic aromatic compounds was a very

  2. Modeling and Simulation of Flow and Formation Damage of Asphalt-Paved Roads

    Directory of Open Access Journals (Sweden)

    M. H. Alawi

    2013-01-01

    Full Text Available Porous asphalt is a standard asphalt built on aggregate storage bed which allows water to drain through it and reduces stormwater runoff. However, porosity of the porous asphalt and the storage bed may be effectively reduced due to trapping suspended solids from the water or from the asphalt damage. In this paper, we present mathematical modeling and numerical simulation of flow and damage of porous asphalt-paved roads. A mathematical model to describe the fine-particles transport carried by a two-phase flow in a porous medium is presented. The buoyancy, capillarity, and mixed relative permeabilities correlations to fit with the mixed-wet system are considered. Throughout this investigation, we monitor the changing of the fluids properties such as water saturation and solid properties such as porosity and permeability due to trapping the fine-particles.

  3. Experimental Study of the Performance of Ultrathin Asphalt Friction Course%超薄磨耗层沥青混合料使用性能试验研究

    Institute of Scientific and Technical Information of China (English)

    曾梦澜; 彭良清; 吴超凡; 谭邦耀

    2012-01-01

    Experiment was conducted to compare skip resistance, penetration and conformation depth of three types of asphalt mixture, which are dense gradation AC-13C, semi-open gradation Novachip⊕ Type C and open gradation OGFC-13. To study influence on interlayer sheer strength by varying layer and tack coat material, wheel rut test specimen was prepared for direct sheer test on pavement structural sheer tester. SBS modified emulsified asphalt and special modified emulsified asphalt Novabond⊕ was equipped in specimen as tack coat, AC-13C,Novachip⊕ Type C,OGFC-13 as wearing layer and AC-20 as middle layer. Results show that maximum cohesive strength of tack coat between different layer materials could be achieved when using optimal tack coat asphalt content For certain pavement structure,special modified emulsified asphalt Novabond⊕ is superior to SBS modified emulsified asphalt as tack coat asphalt Utilizing the same tack coat asphalt,interlayer sheer strength order of different pavement structure is that Novachip⊕ Type C > AC-13C > OGFC-13 in optimal tack coat dosage.%通过试验比较了密级配AC-13C、半开级配Novachip(R) Type C、开级配OGFC-13这3种磨耗层的抗滑、渗水、构造深度等使用性能.以SBS改性乳化沥青及改性乳化沥青NovabondTM为粘层材料,AC-13C、Novachip(R) Type C、OGFC 13作为磨耗层,AC-20C为中面层,制作10 cm复合型车辙试件,采用路面结构层材料剪切试验仪对试件进行直剪试验,分析了粘层种类、用量、磨耗层类型对层间抗剪强度的影响.结果显示,不同面层类型存在粘层油最佳撒布量,此时层间抗剪强度达到最大.对同一种面层类型,改性乳化沥青NovabondTM较SBS改性乳化沥青粘结能力要好.在相同粘层油的最佳撒布量下,不同路面结构抗剪能力依次是Novachip(R)Type C>AC-13C>OGFC-13.

  4. 基于灰关联理论的橡胶粉改性沥青热老化性能研究%Research on Thermal Ageing Performance of Rubber Powder Modified Asphalt Based on Grey Associative Theory

    Institute of Scientific and Technical Information of China (English)

    王宝松; 叶奋

    2012-01-01

    This paper analyzes influences of preparation technology of rubber asphalt on ageing performance of rubber asphalt based on grey associative theory. In order to guarantee accuracy of research on ageing performance of rubber asphalt, .the paper adopts the isolated variable method to test by fixing other factors and transforming single factor and analyze influences of various factors on performance of rubber asphalt. The paper employs grey associative analysis method to analyze degrees of association of multiple groups of data, to study degrees of, association of all influence factors with ageing performance of rubber asphalt, and to determine key factors that affect ageing performance of rubber asphalt.%基于灰关联理论,分析橡胶沥青制备工艺对橡胶沥青老化性能的影响.为保证橡胶沥青老化性能研究的准确性,采用“孤立变量法”,通过固定其他因素并变换单个因素进行试验,分析各种因素对橡胶沥青性能的影响.采用灰关联分析方法对多组数据进行关联度分析,研究各影响因素与橡胶沥青老化性能的关联度大小,确定影响橡胶沥青老化性能的关键因素.

  5. Influence of Garlic Powder on Properties of Asphalt Modified with High Content Rubber Powder%大蒜粉对高用量胶粉改性沥青性能的影响

    Institute of Scientific and Technical Information of China (English)

    刘欣; 万振高; 王乐英; 邵晓瑜

    2016-01-01

    以大蒜粉作胶粉改性沥青的降粘剂,采用布氏粘度计测试了不同胶粉用量+不同大蒜粉用量的改性沥青粘度,还测试了添加大蒜粉后胶粉改性沥青的软化点、针入度和延度等性能,并讨论了降粘剂对胶粉改性沥青降粘效果的影响。结果表明,大蒜粉对胶粉改性沥青有明显的降粘效果,对其他性能也有一定影响;当基质沥青中加入25%胶粉和3%大蒜粉后降粘效果和性能均最佳。%By using garlic powder as viscosity reducer of asphalt modified with rubber powder ,the viscosity of asphalt modified with different content of rubber powder and different content of garlic powder was measured by Brookfield viscometer .The softening point ,penetration and ductility of the asphalt modified with rubber powder were tested after adding garlic powder ,and the influence of vis‐cosity reducer on viscosity reduction effect of the modified asphalt was discussed .The results showed that garlic powder had apparent viscosity‐reducing effect to the modified asphalt ,and the other proper‐ties were also effected .Viscosity‐reducing effect and properties were good after adding 25% rubber pow der and 3% garlic pow der to the base asphalt ,respectively .

  6. Study on Applicability of Natural Gravel Aggregate in Asphalt Concrete Core Wall of Wuyi Reservoir%五一水库天然砾石骨料在沥青混凝土心墙中的适用性研究

    Institute of Scientific and Technical Information of China (English)

    王文政; 唐新军; 何建新; 张涛; 朱西超

    2014-01-01

    Taking the asphalt concrete core wall of Wuyi reservoir sand gravel dam as research object ,the adhesion ex-periment between natural aggregate and asphalt ,mixture ratio designing of natural gravel aggregate ,asphalt and concrete , compression test ,penetration test ,trabecular bending test as well as water stability test were conducted .Then the results were compared with the related data of alkaline dolomite aggregate asphalt concrete .The result suggest that cement ,as filler and the improvement medium ,can significantly improve the adhesion between natural gravel aggregate and asphalt . On this account ,the natural gravel aggregate asphalt concrete can meet the requirements of design specifications ,and it is almost as good as alkaline dolomite aggregate asphalt concrete .%以新疆五一水库砂砾石坝沥青混凝土心墙为例,进行了天然砾石骨料与沥青的黏附性试验、天然砾石骨料沥青混凝土配合比试验以及压缩试验、渗透试验、小梁弯曲试验、水稳定性试验,并与碱性白云岩骨料沥青混凝土相关性能进行对比。结果表明,以水泥作为填料又兼做提高沥青与骨料黏附力的措施,可明显改善天然砾石骨料与沥青胶浆的黏附性,使天然砾石骨料沥青混凝土各项性能指标满足规范要求,且近似达到碱性白云岩骨料沥青混凝土的性能。

  7. Immobilized graphene-based composite from asphalt: Facile synthesis and application in water purification

    Energy Technology Data Exchange (ETDEWEB)

    Sreeprasad, Theruvakkattil Sreenivasan; Gupta, Soujit Sen [DST Unit on Nanoscience, Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036 (India); Maliyekkal, Shihabudheen Mundampra [School of Mechanical and Building Sciences, VIT University, Chennai Campus, Chennai 600048 (India); Pradeep, Thalappil, E-mail: pradeep@iitm.ac.in [DST Unit on Nanoscience, Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036 (India)

    2013-02-15

    Highlights: ► Facile strategy to make graphenic materials from cheaper precursor such as asphalt. ► Material can be made in solution; also as anchored on solid substrates. ► The synthesized material, GSC, was found to be excellent for water purification. ► The applicability was demonstrated through batch and laboratory columns experiments. ► The capacity was compared to other similar adsorbents and was found to be superior. -- Abstract: An in situ strategy for the preparation of graphene immobilized on sand using asphalt, a cheap carbon precursor is presented. The as-synthesized material was characterized in detail using various spectroscopic and microscopic techniques. The presence of G and D bands at 1578 cm{sup −1} and 1345 cm{sup −1} in Raman spectroscopy and the 2D sheet-like structure with wrinkles in transmission electron microscopy confirmed the formation of graphenic materials. In view of the potential applicability of supported graphenic materials in environmental application, the as-synthesized material was tested for purifying water. Removal of a dye (rhodamine-6G) and a pesticide (chlorpyrifos), two of the important types of pollutants of concern in water, were investigated in this study. Adsorption studies were conducted in batch mode as a function of time, particle size, and adsorbent dose. The continuous mode experiments were conducted in multiple cycles and they confirmed that the material can be used for water purification applications. The adsorption efficacy of the present adsorbent system was compared to other reported similar adsorbent systems and the results illustrated that the present materials are superior. The adsorbents were analyzed for post treatment and their reusability was evaluated.

  8. Artificial intelligence modeling to evaluate field performance of photocatalytic asphalt pavement for ambient air purification.

    Science.gov (United States)

    Asadi, Somayeh; Hassan, Marwa; Nadiri, Ataallah; Dylla, Heather

    2014-01-01

    In recent years, the application of titanium dioxide (TiO₂) as a photocatalyst in asphalt pavement has received considerable attention for purifying ambient air from traffic-emitted pollutants via photocatalytic processes. In order to control the increasing deterioration of ambient air quality, urgent and proper risk assessment tools are deemed necessary. However, in practice, monitoring all process parameters for various operating conditions is difficult due to the complex and non-linear nature of air pollution-based problems. Therefore, the development of models to predict air pollutant concentrations is very useful because it can provide early warnings to the population and also reduce the number of measuring sites. This study used artificial neural network (ANN) and neuro-fuzzy (NF) models to predict NOx concentration in the air as a function of traffic count (Tr) and climatic conditions including humidity (H), temperature (T), solar radiation (S), and wind speed (W) before and after the application of TiO₂ on the pavement surface. These models are useful for modeling because of their ability to be trained using historical data and because of their capability for modeling highly non-linear relationships. To build these models, data were collected from a field study where an aqueous nano TiO₂ solution was sprayed on a 0.2-mile of asphalt pavement in Baton Rouge, LA. Results of this study showed that the NF model provided a better fitting to NOx measurements than the ANN model in the training, validation, and test steps. Results of a parametric study indicated that traffic level, relative humidity, and solar radiation had the most influence on photocatalytic efficiency.

  9. Asphalts and asphaltenes: Macromolecular structure, precipitation properties, and flow in porous media

    Science.gov (United States)

    Rassamdana, Hossein

    Depending on rock and fluid properties, more than 50% of reservoir oil in place is normally produced by enhanced oil recovery (EOR) methods. Among the EOR techniques, miscible flooding is one of the most efficient and widely-used methods. However, this method can suffer from the formation and precipitation of asphalt aggregates. In addition, asphalt deposition is also a major hindrance to heavy oil production, and even primary recovery operations. Asphalt deposition can alter the reservoir rock properties, fluid saturation distribution, fluid flow properties, and eventually the ultimate oil recovery. The shortage of studies on the macromolecular structure and growth mechanisms of asphalt particles is the main reason for the unsuccessful modeling of their precipitation properties. The equivocal behavior of asphalt under some specific conditions could be the other reason. In this research we look at the problem of asphalt formation, flow, and precipitation from three different angles. We analyze extensive small-angle X-ray and neutron scattering data, precipitation data, and molecular weight distribution measurements, and show that they all suggest conclusively that asphalts and asphaltenes are fractal aggregates, and their growth mechanisms are diffusion-limited particle (DLP) and diffusion-limited cluster-cluster (DLCC) aggregation processes. These results lead us to development of a scaling equation of state for predicting asphalt precipitation properties, such as its onset and amount of precipitation. Another result of our study is an analytical equation for modeling the molecular weight distribution of asphalt and asphaltene aggregates. In addition, asphalt phase behavior in miscible and immiscible injections is studied. The effect of the governing thermodynamic factors, such as the pressure, temperature, and composition of the oil and precipitation agents, on the asphalt aggregation and disaggregation processes are investigated. Finally, a model is developed to

  10. Microstructural characterization of the chemomechanical behavior of asphalt in terms of aging and fatigue performance properties

    Science.gov (United States)

    Allen, Robert Grover

    The study of asphalt chemo-mechanics requires a basic understanding of the physical properties and chemical composition of asphalt and how these properties are linked to changes in performance induced by chemical modifications. This work uniquely implements the framework of chemo-mechanics by investigating two types of chemical modification processes, natural (oxidative aging) and synthetic (chemical doping) as they relate not only to macro-scale properties of asphalt binder but also to the asphalt microstructure and nanorheology. Furthermore, this study demonstrates the application of atomic force microscopy (AFM) imaging and the extraction of nano-scale engineering properties, i.e. elastic modulus, relaxation modulus, and surface energy, as a method to predict performance related to the fatigue characteristics of asphalt binders by modeling intrinsic material flaws present amongst phase interfaces. It was revealed that oxidative aging induces substantial microstructural changes in asphalt, including variations in phase structure, phase properties, and phase distribution. It has also been shown that certain asphalt chemical parameters have a consistent and measureable effect on the asphalt microstructure that is observed with AFM. In fact, particular phases that emerged via chemical doping revealed a surprising correlation between oxidative aging and the saturates chemical parameter of asphalt in terms of how they explicitly impact durability and performance of asphalt. By implementing a crack initiation model---which requires measureable microstructural characteristics as an input parameter---it was found that microstructural flaws (depending on the extremity) can have a more profound impact on asphalt performance than the properties of the material located between the flaws. It was also discovered by comparing the findings to performance data in the Strategic Highway Research Program's (SHRP's) Materials Reference Library (MRL), that the crack initiation model

  11. TORBED process reactor technology for asphalt paving recycle

    Energy Technology Data Exchange (ETDEWEB)

    Wellwood, G. A. [Torftech Limited, Reading (United Kingdom); Laughlin, R. G. [Torftech Canada Inc., Mississauga, ON (Canada)

    2001-07-01

    Fundamental principles underlying the TORBED reactor technologies are reviewed. Advantages, limitations, and the experience gained in applying the reactor to a range of material processing needs, particularly reprocessing asphalt paving waste, are discussed. The TORBED reactor consists of a compact shallow packed bed of particles suspended above an annular ring of stationary blades through which a process gas stream is passed at high velocity. Unlike fluidized beds, the process gas mass flow can be set to suit the process, i. e. a smaller gas mass flow can be used at a higher velocity at exit from the blades to keep the bed in proper motion. Advantages are: (1) smaller reactor size with rapid start-up and program change, (2) faster and more precise processing of particles, resulting in a consistent product or process, (3) low process stream pressure losses which facilitate process gas recirculation, (4) ability to process widely graded and irregularly shaped feed stocks, and (5) simplicity of operation through real time control. The 'expanded' version of the TORBED reactor also permits fuel injection to generate process gas temperatures in excess of 1600 degrees C, and allows high gas flow rates with low pressure drop. When used to reprocess asphalt paving waste, the coal tar, used in some 25 per cent of existing roads in the Netherlands, can be easily removed and destroyed and the cleaned stone and the energy generated form the destruction of the coal tar, can be reused in creating new bitumen- containing asphalt paving. Excellent results are reported to have been obtained in pilot studies. Pilot trial also have been conducted on the combustion of wood waste for power generation, with encouraging results. Other pilot projects addressed alternative cementitious materials. 5 refs.

  12. Effect of crumb rubber on asphaltic binder chemistry and rheology

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Cicero de S.; Tome, Luisa G.A.; Sant' ana, Hosiberto B.; Soares, Jorge B.; Soares, Sandra A. [University Federal of Ceara, Fortaleza, CE (Brazil)

    2008-07-01

    The use of the crumb rubber (CR) from scraps tires to modify asphalt binders (AB) at high temperature can improve significantly the performance grade, but the storage stability can be influenced after the mix of AB and CR or polymer. The major concern of asphalt binder with polymer and CR blends is their lack of stability during prolonged storage at high temperatures. The tendency to phase separation under quiescent conditions appears as an important limitation for the practical use of these blends. After the RTFOT and PAV process, the binder conventional and modified was analyzed in a Fourier Transform Infrared spectrometer (FTIR) for chemical characterization. After aging in RTFOT, the AB presented a larger degradation compared to the CR of RABC and RABC commercial. So, the crumb rubber contributed to the binder stability, acting as an antioxidant in the aging process. The dynamic mechanical properties of CR modify asphalts binder before and after graft has been characterized by use of dynamic shear rheometer (DSR) or advances rheology expanded system (ARES) of Rheometric Scientific. The difference in the viscoelastic parameters between the top and the bottom sections of the tube was measured. It has been found that the added content of CR has great effect on the rheological properties of the AB and its high temperature performance. It also has been confirmed that the RABC sample showed larger storage stability compared to the sample RABC commercial observed with viscoelastic parameters. As a consequence, the use CR and aromatic oil can be considered a suitable alternative for modification of binder in pavement. (author)

  13. The influence of additives on asphalt combustibility performance%添加剂对沥青燃烧性能的影响

    Institute of Scientific and Technical Information of China (English)

    董瑞琨; 苏胜斌; 任俊; 樊德

    2011-01-01

    The warm mix asphalt modifier is often used to decrease the paving or rolling temperature during the pavement construction in the tunnel or other special environment. But there is little research on whether the warm-mixing modifier affects the asphalt combustibility performance. In this paper, three different additives ADZ,ADW,ADS are selected and blended to different asphalt respectively,and the oxygen indexes are tested through the digital oxygen index meter. The effects of additive on the combustibility performance of asphalt or flame retardant asphalt are discussed. The experimental results indicated that three kinds of additives have no adverse effects on the combustion performance of asphalt,and will not affect the flame retardant properties.%温拌改性剂可以有效地降低摊铺或碾压温度,有利于隧道等特殊环境的路面施工,但关于温拌改性剂是否会影响沥青燃烧性能的研究却很少.分别选取3种不同添加剂ADZ、ADW、ADS加入到不同沥青中,利用数显氧指数仪测试其氧指数.探讨添加剂的加入在实现降低摊铺或碾压温度的情况下是否会影响沥青的燃烧性能,是否会对阻燃剂的阻燃效果产生影响.实验结果表明,3种添加剂在实现降低摊铺或碾压温度的同时不会对沥青的燃烧性能产生不利影响.同时,3种添加剂的加入也不会影响阻燃剂的阻燃性能.

  14. 水泥路面加铺沥青改造质量控制技术%Paving asphalt concrete pavement quality control techniques

    Institute of Scientific and Technical Information of China (English)

    王小兵

    2014-01-01

    总结归纳了旧路面病害检测的内容及方法,从施工管理角度出发,对沥青面层的加铺进行了质量控制,包括沥青、集料、设置试验段等内容,并通过平整度、渗水系数等控制掺量检验,对改造工程质量进行了检查验收。%This paper sums up the old road surface plant disease detection contents and methods, from the angle of construction management of asphalt road surface of the road to quality control, such as asphalt, aggregate, set up test section content, finally, through permeable coefficient control parameter inspection, inspection on project quality acceptance.

  15. Experimental Study of Asphalt Mixture Warm-mixing agent%“H-1”沥青混合料温拌剂的试验研究

    Institute of Scientific and Technical Information of China (English)

    陈博

    2015-01-01

    The“H-1”is a new type of asphalt mixture warm-mixing agent. This paper introduces the results of following laboratory tests:the effects of“H-1”agent on lowering the mixture mixing and compacting temperature and the influence of it on the performances of asphalt mixture.%“H-1”是一种新型的矿物类沥青混合料温拌剂。本文介绍“H-1”温拌剂降温效果及其对混合料性能影响的实验室试验结果。

  16. Performance evaluation indicator of ultra-thin wearing course asphalt mixture%超薄磨耗层沥青混合料评价指标

    Institute of Scientific and Technical Information of China (English)

    谭忆秋; 姚李; 王海朋; 边鑫; 齐宇翔

    2012-01-01

    为了科学地选择和评价超薄磨耗层沥青混合料,选取SMA-10,UTAC-10和NovaChip Type-C 3种混合料类型作为评价性能指标,采用约束试件温度应力试验评价混合料的低温性能,通过渗水系数试验和抗滑性能试验评价混合料的表面性能,设计一种室内磨耗试验来研究混合料抵抗抗滑衰减的能力.采用一套3种条件下的飞散试验并结合冻融劈裂试验评价混合料的抗水损害性能.结果表明:冻断温度和冻断强度可有效评价磨耗层沥青混合料的低温性能,以初始摆值结合抗滑衰减程度评价磨耗层抗滑性能比较科学,评价超薄磨耗层材料的抗水损害能力须将冻融劈裂强度比和冻融劈裂强度结合起来.%To scientifically select and evaluate ultra-thin wearing course asphalt mixture,three types of asphalt mixture,SMA-10,UTAC-10 and NovaChip Type-C were selected to study the performance evaluation indicator.The low temperature performance of mixture was evaluated by use of thermal stress rest rained specimen test,and the surface performance was evaluated by permeable coefficient test and anti-slide performance test.A kind of indoor abrasion test was designed to evaluate the skid resistance attenuation property of asphalt mixture,and a set of dispersion tests under three conditions was designed combining with freeze-thaw splitting test to evaluate water damage resistance performance of asphalt mixture.The results show that the frozen broken temperature and frozen broken strength can effectively evaluate the low temperature performance of ultra-thin wearing course asphalt mixture.It is scientific to use initial value of BPN and sliding attenuation degree to evaluate skid resistance performance of ultra-thin wearing course.Freeze-thaw splitting strength ratio and freeze-thaw splitting strength should be combined to evaluate resistance water damage performance.

  17. A liquid chromatography-atmospheric pressure photoionization tandem mass spectrometric method for the determination of organosulfur compounds in petroleum asphalt cements.

    Science.gov (United States)

    da Silveira, Géssica Domingos; Faccin, Henrique; Claussen, Luis; Goularte, Rayane Bueno; Do Nascimento, Paulo C; Bohrer, Denise; Cravo, Margareth; Leite, Leni F M; de Carvalho, Leandro Machado

    2016-07-29

    We present a sensitive liquid chromatography-atmospheric pressure photoionization tandem mass spectrometric (UHPLC-APPI-MS/MS) method for the determination of selected organosulfur compounds in Brazilian asphalt cements. It was possible to detect 14 organosulfur compounds of different classes where sulfoxides and sulfones presented higher sensibility in ionization than thiophenes and aromatic sulfides. A dopant-assisted APPI method was also tested, however, when chromatographic flow rate was optimized a decrease in signal was observed for all compounds. PAHs were tested and ruled out as possible interfering compounds and the matrix effect of asphalt cements was within an acceptable range for the quantification of organosulfur compounds. The proposed method was found to have satisfactory linearity and accuracy with recoveries between 83.85 and 110.28% for thianaphthene and 3-methylbenzothiophene, respectively. Therefore, the method allowed the characterization of organosulfur compounds in Brazilian asphalt cements and demonstrated changes in the amount quantified in asphaltenic and maltenic fractions after the RTFOT+SUNTEST aging process.

  18. Load Response Analysis of Asphalt Pavement

    Directory of Open Access Journals (Sweden)

    Xiao Zhijun

    2016-01-01

    Full Text Available Based on the filed data of Fuzhou test road, load response regulation of nonlinear pavement structure was analyzed in this paper; Mechanics software was adopted to analyze linear elastic and nonlinear of the pavement structure, analyzed results and road filed data were compared, and determine the correlation between them and the field data.

  19. LABORATORY SIMULATION OF POROUS ASPHALT PARKING LOT SYSTEM AND MIX DESIGN FOR STORM WATER MANAGEMENT

    Directory of Open Access Journals (Sweden)

    M. O. HAMZAH

    2013-04-01

    Full Text Available Porous asphalt pavement was initially developed for the purpose of improving road safety, best candidate material for quiet pavement and to avoid aquaplaning and skidding in wet weather. However, from previous studies, porous asphalt is able to mitigate surface runoff. Porous asphalt parking lots with underlying reservoir course perform as additional temporary water storage matrix that enables reduction of flash flood. This paper elaborates the development of a new porous asphalt aggregate grading design for storm water mitigation using the Nominal Maximum Aggregate Size (NMAS 20 mm. The properties of the mixes were quantified and evaluated in terms of air voids, permeability, abrasion loss and indirect tensile strength. It was found that the proposed gradation has the best permeability and Indirect Tensile Strength (ITS values when compacted at 50 blows per face with a standard Marshal compactor. The porous asphalt slab was prepared using a slab compactor to simulate porous parking lot paving at site. The porous asphalt slab was finally placed inside a locally fabricated water flow simulator to simulate a porous asphalt pavement system for parking lots.

  20. A Study of Moisture Damage in Plastomeric Polymer Modified Asphalt Binder Using Functionalized AFM Tips

    Directory of Open Access Journals (Sweden)

    Rafiqul Tarefder

    2011-12-01

    Full Text Available In this study, moisture damage in plastomeric polymer modified asphalt binder is investigated using Atomic Force Microscopy (AFM with chemically functionalized AFM tips. Four different percentages of plastomeric polymers and two antistripping agents such as Kling Beta and Lime are used to modify a base asphalt binder. Chemical functional groups such as -COOH, -CH3, -NH3, and –OH, that are commonly present in plastomeric polymer modified asphalt system, are used to functionalize the AFM tips. The force distance mode of AFM is used to measure the adhesion forces between a modified asphalt sample surface and the functionalized AFM tips. This enables the measurement of adhesion within an asphalt binder system. It is shown that the adhesion force values in dry sample changed substantially from that in wet conditioned samples. It is evident from this study that plastomeric modification does not help reduce moisture damage in asphalt. The percentage change in adhesion forces due to moisture is about 20 nN for the lime modified samples, and about 50 nN for the Kling Beta modified samples. This indicates that lime is more effective than Kling Beta for reducing moisture damage in plastomeric polymer modified asphalt.