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Sample records for bituminous concrete pavements

  1. A Method to Estimate the Dynamic Displacement and Stress of a Multi-layered Pavement with Bituminous or Concrete Materials

    OpenAIRE

    LU, ZHENG; Yao, Hailin; Zhang, JingBo

    2014-01-01

    In this research work, a method to estimate the dynamic characteristics of a multilayered pavement with bituminous or concrete materials is proposed. A mechanical model is established to investigate the dynamic displacement and stress of the multi-layered pavement structure. Both the flexible and the rigid pavements, corresponding to bituminous materials and concrete materials, respectively, are studied. The theoretical solutions of the multi-layered pavement structure are deduced considering...

  2. A Method to Estimate the Dynamic Displacement and Stress of a Multi-layered Pavement with Bituminous or Concrete Materials

    Directory of Open Access Journals (Sweden)

    Zheng LU

    2014-12-01

    Full Text Available In this research work, a method to estimate the dynamic characteristics of a multilayered pavement with bituminous or concrete materials is proposed. A mechanical model is established to investigate the dynamic displacement and stress of the multi-layered pavement structure. Both the flexible and the rigid pavements, corresponding to bituminous materials and concrete materials, respectively, are studied. The theoretical solutions of the multi-layered pavement structure are deduced considering the compatibility condition at the interface of the structural layers. By introducing FFT (Fast Fourier Transform algorithm, some numerical results are presented. Comparisons of the theoretical and experimental result implied that the proposed method is reasonable in predicting the stress and displacement of a multi-layered pavement with bituminous or concrete materials. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6071

  3. Precast concrete pavements

    Science.gov (United States)

    Rollings, R. S.; Chou, Y. T.

    1981-11-01

    This report reviewed published literature on precast concrete pavements and found that precast concrete pavements have had some limited application in airfields, roads, and storage areas. This review of past experience and an analytical study of precast slabs concluded that existing design and construction techniques can be adapted for use with precast concrete pavements, but more work is needed to develop effective and easily constructed load transfer designs for slab joints. Precast concrete does not offer any advantage for conventional pavements due to its high cost and surface roughness, but it may find applications for special problems such as construction in adverse weather, subgrade settlement, temporary pavements that need to be relocated, and military operations.

  4. Discussion on Overlaying Bituminous Concrete Pavement on the Old Cement Concrete Pavement Construction%旧水泥混凝土路面加铺沥青混凝土面层施工探讨

    Institute of Scientific and Technical Information of China (English)

    何拥宁

    2011-01-01

    近年来,随着交通量的剧增和汽车轴载日益重型化,原有的水泥混凝土路面已经出现露骨、开裂、断板、沉陷、错台、破碎、板底脱空等路面损坏,影响了道路的使用功能,面临着修复工作.本文结合了工程实际,对"刚改柔"的施工方法进行了总结.%In recent years, with the sharp increase in traffic and more heavy-duty vehicle axle load, the original cement concrete pavement has emerged cracking, breaking boards, subsidence, dislocation, broken and plate bottom gap which affects the function of road and faced with repair work.Combined with engineering practice, the construction method of changing rigid to flexible is summarized.

  5. Development of New Bituminous Pavement Design Method

    DEFF Research Database (Denmark)

    Ullidtz, Per

    The report and work of COST Action 333 sets in place the foundation for a coherent, cost-effective and harmonised European pavement design method. In order to do this, the work programme focused on information gathering, identification of requirements and the selection of the necessary design...

  6. The Concrete and Pavement Challenge

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    The modern world is characterized by the extensive use of concrete and asphalt pavement. Periodically, these materials are replaced and the old materials disposed of. In this challenge, students will be asked to develop ways to reuse the old materials. It is important for students to understand how concrete and asphalt are made and applied, as…

  7. A study of bituminous pavements to determine a correlation between pavement structure designs and tripping of asphalt cement

    Science.gov (United States)

    Barton, B. R.

    1984-03-01

    After detecting a few cases of stripping of asphalt cement from the aggregate in bituminous pavement, there was concern that stripping might be a widespread problem in the state. It is agreed that water is the cause of stripping, and it was the opinion of some that pavements on granular bases would be less likely to strip because of supposedly better drainage characteristics. Differently designed pavement structures in all areas of the state were investigated to determine if there is a correlation between base and pavement design and stripping. Stripping was not as widespread as had been feared and there was less stripping in fulldepth bituminous base and pavement constructed over a lime-treated subgrade than in pavements constructed oer granular bases. This was contrary to what some had theorized.

  8. Locating the Drainage Layer for Bituminous Pavements in Indiana

    OpenAIRE

    Hassan, Hossam Farouk.; White, Thomas D.

    1996-01-01

    Pavement subsurface drainage and its effect on pavement performance has been a subject of interest since the 18th and 19th centuries. With no doubt the detrimental effects of heavy wheel loads on pavements with saturated base material is a significant factor. The consequence of subsurface water on pavement performance includes premature rutting, cracking, faulting, and increased roughness, all of which lead to a decrease in serviceability. This research study involves the evaluation of the...

  9. Effect of thickness variation of bituminous layer in the structural responses of flexible pavements

    Directory of Open Access Journals (Sweden)

    Juliana Pavan Vidotto

    2014-05-01

    Full Text Available In this work, a sensitivity analysis was performed to investigate the effect of thickness variation of bituminous layer in the structural responses of flexible pavements and, therefore in performance. For this, it used traffic data from a weigh station located at Km 28 of the Immigrants Highway, at state of Sao Paulo, whose data collection was realized in 2008. The loads deriving from traffic were applied to the computational program ELSYM5 to obtain structural responses related to damage such as fatigue cracks and rutting. With these values, the damage factors were calculated and then the sensitivity analysis related to the thickness variation of bituminous layer was performed. Through the obtained results was concluded that the variation of thickness of bituminous layer have an influence on structural responses, and that damage factors related to fatigue cracks were more sensitive than those factors related to rutting.

  10. Long-Term Field Performance of Pervious Concrete Pavement

    OpenAIRE

    Aleksandra Radlińska; Andrea Welker; Kathryn Greising; Blake Campbell; David Littlewood

    2012-01-01

    The work described in this paper provides an evaluation of an aged pervious concrete pavement in the Northeastern United States to provide a better understanding of the long-lasting effects of placement techniques as well as the long-term field performance of porous pavement, specifically in areas susceptible to freezing and thawing. Multiple samples were taken from the existing pavement and were examined in terms of porosity and unit weight, compressive and splitting tensile strength, and th...

  11. Use of Recycled Aggregate and Fly Ash in Concrete Pavement

    Directory of Open Access Journals (Sweden)

    Myle N. James

    2011-01-01

    Full Text Available Problem statement: Recycled materials aggregate from the demolished concrete structures and fly ash from burning coal shows the possible application as structural and non structural components in concrete structures. This research aims to evaluate the feasibility of using concrete containing recycled concrete aggregate and fly ash in concrete pavement. Approach: Two water cement ratio (0.45 and 0.55 the compressive strength, modulus of electricity and flexural strength for concrete with recycled aggregate and fly ash with 0, 25% replacing cement in mass were considered. Results: The material properties of recycled aggregate concrete with fly ash indicate comparable results with that of concrete with natural aggregate and without fly ash. Conclusion/Recommendations: The recycled materials could be used in concrete pavement and it will promote the sustainability of concrete.

  12. Noise emission of concrete pavement surfaces produced by diamond grinding

    Directory of Open Access Journals (Sweden)

    Jens Skarabis

    2015-04-01

    Full Text Available In Germany, diamond grinding is frequently used to improve the evenness and skid resistance of concrete pavement surfaces. Since diamond grinding has been observed to affect tyre/pavement noise emission favourably, the relationship among surface texture, concrete composition and noise emission of concrete pavement surfaces has been systematically investigated. The simulation program SPERoN was used in a parameter study to investigate the main factors which affect noise emission. Based on the results of the simulations, textured concrete surfaces were produced by using a laboratory grinding machine. As well as the composition of the concrete, the thickness and spacing of the diamond blades were varied. The ability of the textured surfaces to reduce noise emission was assessed from the texture characteristics and air flow resistance of textured surfaces measured in the laboratory. It was found that concrete composition and, in particular, the spacing of the blades affected the reduction in noise emission considerably. The noise emission behaviour of numerous road sections was also considered in field investigations. The pavement surfaces had been textured by diamond grinding during the last years or decades. The results show that diamond grinding is able to provide good, durable noise-reducing properties. Several new pavement sections were investigated using thicknesses and spacings of the blades similar to those used in the laboratory to optimize noise emission reduction. It is concluded that diamond grinding is a good alternative to exposed aggregate concrete for the production of low-noise pavement surfaces.

  13. Use of Recycled Aggregate and Fly Ash in Concrete Pavement

    OpenAIRE

    Myle N. James; Wonchang Choi; Taher Abu-Lebdeh

    2011-01-01

    Problem statement: Recycled materials aggregate from the demolished concrete structures and fly ash from burning coal shows the possible application as structural and non structural components in concrete structures. This research aims to evaluate the feasibility of using concrete containing recycled concrete aggregate and fly ash in concrete pavement. Approach: Two water cement ratio (0.45 and 0.55) the compressive strength, modulus of electricity and flexural streng...

  14. Recycling of polyethylene terephthalate (PET plastic bottle wastes in bituminous asphaltic concrete

    Directory of Open Access Journals (Sweden)

    Adebayo Olatunbosun Sojobi

    2016-12-01

    Full Text Available This research sheds light on the concept of eco-friendly road construction which comprises eco-design, eco-extraction, eco-manufacturing, eco-construction, eco-rehabilitation, eco-maintenance, eco-demolition, and socioeconomic empowerment. It also revealed the challenges being faced in its adoption and the benefits derivable from its application. Furthermore, the effects of recycling PET plastic bottle wastes produced in North Central Nigeria in bituminous asphaltic concrete (BAC used in flexible pavement construction were also evaluated. The mix design consists of 60/70 penetration-grade asphaltic concrete (5%, 68% coarse aggregate, 6% fine aggregate, and 21% filler using the dry process at 170°C. The optimum bitumen content (OBC for conventional BAC was obtained as 4% by weight of total aggregates and filler. Polymer-coated aggregate (PCA-modified BAC seems preferable because it has the potential to utilize more plastic wastes with a higher optimum plastic content (OPC of 16.7% by weight of total aggregates and filler compared to that of 9% by weight of OBC achieved by PMB-BAC. For both PMB- and PCA-modified BAC, an increase in air void, void in mineral aggregate, and Marshall stability were observed. Eco-friendly road construction which recycles PET wastes should be encouraged by government considering its potential environmental and economic benefits.

  15. Effect of Cement on Properties of Over-Burnt Brick Bituminous Concrete Mixes

    Science.gov (United States)

    Sarkar, Dipankar; Pal, Manish

    2016-06-01

    The present investigation is carried out to propose the use of cement coated over burnt brick aggregate in the preparation of bituminous concrete mix. The effect of cement on various mechanical properties such as Marshall stability, flow, Marshall quotient (stability to flow ratio), indirect tensile strength, stripping, rutting and fatigue life of bituminous concrete overlay has been evaluated. In this study, different cement percentages such as 2, 3, 4 and 5 % by weight of aggregate have been mixed with Over Burnt Brick Aggregate (OBBA). The laboratory results indicate that bituminous concrete prepared by 4 % cement coated OBBA gives the highest Marshall stability. The bituminous concrete mix with 4 % cement shows considerable improvement in various mechanical properties of the mix compared to the plain OBBA concrete mix.

  16. Bearing capacity evaluation of rubblized concrete pavements

    Directory of Open Access Journals (Sweden)

    González, M.

    2009-03-01

    Full Text Available The paper presents the findings of a research work performed on a real scale concrete pavement project where Rubblizing technology was used for its structural rehabilitation. Rubblizing may be defined as a fracture technique in which a concrete pavement slab is transformed in a granular base with a very high Modulus. This technique, fractures the concrete slab in angular pieces by using a concentrated dynamic load of low amplitude and high frequency. The research work was based on field study on the rehabilitation of 5 km motorway. The structural evaluations where made, before, during and after one year construction. Measurements and site evaluation where made by using DCP, Light Weight Deflectometer and FWD (on top of asphalt layer and excavating inside pits. The structural capacity of the Rubblized layer was evaluated through theoretical analysis. Because of the anisotropic properties of the Rubblized layer the results are presented using AASHTO structural layer coefficient. The structural layer coefficients recommended are between the range of 0.25 and 0.30 for concrete slabs with thickness grater than 220 mm.El trabajo presenta los resultados de un estudio a escala real de la capacidad estructural de un firme de hormigón rehabilitado utilizando la técnica de Rubblizing. La técnica de Rubblizing ha sido traducida como el pulverizado del firme de hormigón pero, es más bien un efecto combinado de trituración y fracturación de la losa de hormigón en todo su espesor para convertir esta en una base granular de alto módulo. Esta tecnica fractura la losa de hormigón en trozos angulares y entrelazados empleando una carga dinámica concentrada, de baja amplitud y alta frecuencia. La investigación se basó en el estudio de la rehabilitación de 5 km de autopista. Los estudios de la capacidad estructural fueron realizados durante, al término y un año después de la construcción. Para las mediciones y evaluaciones de terreno se utilizó, el

  17. Shakedown analysis of anisotropic asphalt concrete pavements with clay subgrade

    Energy Technology Data Exchange (ETDEWEB)

    Boulbibane, M.; Collins, I.F. [Auckland Univ., Auckland (New Zealand). Dept. of Engineering Science; Weichert, D. [RWTH-Aachen Inst. of General Mechanics, Aachen (Germany); Raad, L. [Alaska-Fairbanks Univ., Fairbanks, AK (United States). Transportation and Research Centre

    2000-08-04

    A mathematical model has been presented which can predict the effect of inherent anisotropic cohesion on the long-term behaviour of multilayered pavements. The model is based on the lower bound theorem of shakedown analysis and makes allowances for variations of soil strength with direction. Pavements operating above the critical shakedown load exhibit plastic strains under long term repeated loading conditions and eventually result in deep ruts. This model was used to examine the influence of subgrade properties on the shakedown behaviour of two-layer pavement systems consisting of an asphalt concrete layer and a granular base over a clay subgrade. The shakedown load for pavements under repeated loadings was estimated and the effects of variables such as temperature, asphalt thickness, stiffness and strength were determined. The materials in the various layers of the pavement were modeled as elastic-plastic Mohr-Coulomb materials. 38 refs., 3 tabs., 5 figs.

  18. Long-Term Field Performance of Pervious Concrete Pavement

    Directory of Open Access Journals (Sweden)

    Aleksandra Radlińska

    2012-01-01

    Full Text Available The work described in this paper provides an evaluation of an aged pervious concrete pavement in the Northeastern United States to provide a better understanding of the long-lasting effects of placement techniques as well as the long-term field performance of porous pavement, specifically in areas susceptible to freezing and thawing. Multiple samples were taken from the existing pavement and were examined in terms of porosity and unit weight, compressive and splitting tensile strength, and the depth and degree of clogging. It was concluded that improper placement and curing led to uneven pavement thickness, irregular pore distribution within the pervious concrete, and highly variable strength values across the site, as well as sealed surfaces that prevented infiltration.

  19. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

    Directory of Open Access Journals (Sweden)

    Isamu Yoshitake

    2015-08-01

    Full Text Available Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

  20. Thin, applied surfacing for improving skid resistance of concrete pavements

    Science.gov (United States)

    Scholer, C. F.

    1980-12-01

    The use of select aggregate in a thin wearing surface of portland cement mortar to prolone or restore a concrete pavement's ability to develop high friction was accomplished. Two fine aggregates, blast furnace slag and lightweight expanded shale were found to exhibit skid resistance greater than the other aggregates evaluated. The British polishing wheel was used in the laboratory evaluation of aggregate to simulate wear. The need for a method of restoring friction to a worn, but otherwise sound concrete pavement led to a field evaluation of several different techniques for placing a very thin overlay. The successful method was a broomed, very thin layer of mortar, 3 mm thick.

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

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    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.

  2. Optimisation of the Crack Pattern in Continuously Reinforced Concrete Pavements

    NARCIS (Netherlands)

    Ren, D.

    2015-01-01

    Recent field investigations on several new Continuously Reinforced Concrete Pavements (CRCP) in Belgium indicate that its crack pattern is characterized by low mean crack spacing along with a high percentage of clusters of closely spaced cracks. Field surveys also indicate that it is difficult to si

  3. Design Basis for Fibre Reinforced Concrete (FRC) Pavements

    DEFF Research Database (Denmark)

    Bendixen, Søren; Stang, Henrik

    1996-01-01

    -crack opening relationship can beused to descibe the properties of fibre reinforced concrete (FRC) intension and how the stress-crack opening relationship can beapplied in a simple design scheme for pavements. The projectincludes development of design tools, experiments to determine thestress-crack opening...

  4. EVALUATION OF TIRE RUBBER DISPOSAL IN CONCRETE FOR PAVEMENTS

    Directory of Open Access Journals (Sweden)

    Rosa Cristina Cecche Lintz

    2009-12-01

    Full Text Available The production of waste by the tire industry has been a growing problem, indicating the need for its reuse. More than thirty million tires are discharged per year in Brazil, where regulation for the environment states that for each four new tires, five unusable ones must be adequately disposed by manufacturers and importers. Paving consumes an extremely large quantity of materials, which can be the source of rational application of waste and rejected materials. Research shows that tire rubber can be added to asphalt, which increases its durability and improves pavement quality and safety conditions by absorbing the rubber elastic properties, and also be used for architectural applications, among others. This study deals with the addition of rubber fibers from tire crushing in concrete for roadway pavements in order to provide proper indication about the alternative material disposal through an evaluation of the mechanical behavior of the modified concrete. Different concrete mixes were produced, within which, part of fine aggregates were substituted by tire rubber and mechanical experiment tests were performed, which show that, due to great resistance losses, the disposal of this alternative material in concrete should be considered for light traffic pavements, with the addition of rubber ranging up to 10% in mass.

  5. Influential Factors on Deicing Performance of Electrically Conductive Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    TANG Zuquan; QIAN Jueshi; LI Zhuoqiu; WU Chuanming

    2006-01-01

    The deicing experiment of carbon fiber reinforced electrically conductive concrete (CFRC) slab was conducted in laboratory at first, then the deicing process of CFRC pavement was analyzed by means of finite element method (FEM). At last, based on the energy conservation law and the computing results of finite element method, the influential factors including the setting of electric heating layer, environmental temperature, the thickness of ice, material parameters, and deicing power on deicing performance and energy consumption were discussed.

  6. Porous concrete mixtures for pervious urban pavements

    OpenAIRE

    Castro, J.; Fernández, B.; Videla, C.; de Solminihac, H.

    2007-01-01

    The present study aimed to analyze the hydraulic and mechanical behaviour of a series of roller-compacted, laboratory porous concrete mixtures. The mix design variables examined were the actual void ratio in the hardened concrete and the water/cement ratio. From these results the better dosages from the mechanical and hydraulical behaviour point of view were determined. One of the designs developed was found to exhibit excellent hydraulic capacity and 20% greater strength than the mixtures re...

  7. Asphaltic concrete overlays of rigid and flexible pavements

    Science.gov (United States)

    Kinchen, R. W.; Temple, W. H.

    1980-10-01

    The development of a mechanistic approach to overlay thickness selection is described. The procedure utilizes a deflection analysis to determine pavement rehabilitation needs. Design guides for selecting the overlay thickness are presented. Tolerable deflection-traffic load relationships and the deflection attenuation properties of asphaltic concrete were developed, representing the subgrade support conditions and properties of materials used in Louisiana. All deflection measurements on asphaltic concrete were corrected for the effect of temperature. Deflection measurements taken before and after overlay were also adjusted to minimize the effects of seasonal subgrade moisture variation.

  8. Synthesis report: D-cracking in portland cement concrete pavements

    Science.gov (United States)

    Thompson, S. R.; Olsen, M. P. J.; Dempsey, B. J.

    1980-06-01

    The mechanisms and testing procedures for D-cracking in portland cement concrete pavements are examined. Benefication procedures are also investigated. The three general responses to freezing in the aggregate/paste system include elastic accommodation, high internal pressure, and high external pressure. It is found that the critical aggregate parameters influencing D-cracking are degree of saturation, maximum particle size, permeability, porosity, and pore size distribution. Evaluation of present laboratory testing procedures indicated that the ASTM C666, VPI slow-cool, Mercury Porosimetry, and Iowa Pore Index Tests correlated the best with field performance of concrete with respect to D-cracking.

  9. Characterization and modelling of self healing of bituminous materials towards durable asphalt pavement

    NARCIS (Netherlands)

    Qiu, J.; Van de Ven, M.F.C.; Schlangen, H.E.J.G.; Wu, S.; Molenaar, A.A.A.

    2012-01-01

    The traffic volume and the number of heavy vehicles are growing enormously nowadays. There is a need for designing a durable asphalt pavement with innovative technologies. Pavement structures and materials with self healing and self repairing capability are believed to be very useful in such a syste

  10. Reuse of Lathe Waste Steel Scrap in Concrete Pavements

    Directory of Open Access Journals (Sweden)

    Pooja Shrivastavaa

    2014-12-01

    Full Text Available These project works assess on the study of the workability and mechanical strength properties of the concrete reinforced with industrialized waste fibers or the recycled fibers. In each lathe industries wastes are available in form of steel scraps are yield by the lathe machines in process of finishing of different machines parts and dumping of these wastes in the barren soil contaminating the soil and ground water that builds an unhealthy environment. Now a day’s these steel scraps as a waste products used by innovative construction industry and also in transportation and highway industry. In addition to get sustainable progress and environmental remuneration, lathe scrap as worn-recycle fibers with concrete are likely to be used. When the steel scrap reinforced in concrete it acquire a term; fiber reinforced concrete and steel fibers in concrete defined as steel fiber reinforced concrete (SFRC.Different experimental studies are done to identify about fresh and hardened concrete properties of steel scrap fiber reinforced concrete (SSFRC and their mechanical properties are found to be increase due to the addition of steel scrap in concrete i.e. compressive strength, flexural strength, impact strength, fatigue strength and split tensile strength were increased but up to 0.5-2% scrap content . When compared with usual concrete to SSFRC, flexural strength increases by 40% and considerable increases in tensile and compressive strength. These steel scrap also aid to improve the shrinkage reduction, cracking resistance i.e. preventing crack propagation and modulus of elasticity. The workability of fresh SSFRC are carried out by using slump test but it restricted to less scrap contents. This work focuses on the enhancement of structural strength and improvement in fatigue life of concrete pavements by reuse of scrap steel in concrete. These concrete roads with SSFRC promises an appreciably eminent design life, offer superior serviceability and

  11. The microstructure of petroleum vacuum residue films for bituminous concrete: a microscopy approach.

    Science.gov (United States)

    Sourty, E D; Tamminga, A Y; Michels, M A J; Vellinga, W-P; Meijer, H E H

    2011-02-01

    Selected carbon-rich refinery residues ('binders') mixed with mineral particles can form composite materials ('bituminous concrete') with bulk mechanical properties comparable to those of cement concrete. The microstructural mechanism underlying the remarkable composite properties has been related to the appearance of a rigid percolating network consisting of asphaltenes and mineral particles [Wilbrink M. et al. (2005) Rigidity percolation in dispersions with a structured visco-elastic matrix. Phys. Rev. E71, 031402]. In this paper, we explore the microstructure of thin binder films of varying thickness with a number of microscopic characterization techniques, and attempt to relate the observed microstructure to the distinctive mechanical behaviour. Two binders, only one of which has been proven to be suitable for bituminous concrete were investigated, and their microstructure compared. Both binders show the formation of asphaltene aggregates. The binder suitable for bituminous concrete is distinguished by the fact that the asphaltenes show a stronger tendency towards such aggregation, due to a higher concentration and less stabilization in the maltene phase. They also show a clear affinity to other species (such as waxes) and may act as nucleation sites for crystals and aggregates of those species. PMID:21118207

  12. Porous concrete mixtures for pervious urban pavements

    Directory of Open Access Journals (Sweden)

    Castro, J.

    2007-08-01

    Full Text Available The present study aimed to analyze the hydraulic and mechanical behaviour of a series of roller-compacted, laboratory porous concrete mixtures. The mix design variables examined were the actual void ratio in the hardened concrete and the water/cement ratio. From these results the better dosages from the mechanical and hydraulical behaviour point of view were determined. One of the designs developed was found to exhibit excellent hydraulic capacity and 20% greater strength than the mixtures recommended in the literature. Moreover, concrete with an actual void ratio of only 14% was observed to meet permeability requirements. Maximum flexural strength of concretes with different w/c ratios was achieved with a cement paste content of 250 l/m3. Relationships were found between the void ratio and both 28-day concrete permeability and flexural strength. Finally, the doses exhibiting the best mechanical and hydraulic performance were identified.El trabajo realizado en este estudio consistió en analizar el comportamiento de diferentes dosificaciones de mezclas de hormigón poroso, fabricadas en laboratorio y compactadas con rodillo pesado para simular las condiciones de terreno. Las variables consideradas para el diseño de las mezclas fueron el porcentaje real de huecos en el hormigón endurecido y la razón agua/cemento. A partir de estos resultados se determinaron las dosificaciones que presentan mejor comportamiento desde el punto de vista mecánico e hidráulico. Los resultados muestran que existe una dosificación de hormigón poroso, distinta a las encontradas actualmente en la literatura internacional, que permite obtener resistencias hasta 20% más altas, manteniendo todavía una excelente capacidad hidráulica. Se determinó que una permeabilidad suficiente se puede obtener con un porcentaje real de huecos de 14%, y que agregar pasta de cemento en una proporción de 250 l/m3 permite maximizar la resistencia a flexotracción de hormigones que

  13. ESTIMATION OF THE CONCRETE PAVEMENT TEMPERATURE FIELDS AND THEIR GRADIENTS

    Directory of Open Access Journals (Sweden)

    M. K. Pshembaev

    2015-01-01

    Full Text Available The heat fluxes impact on the road-dressing concrete surfacing under different regions climatic conditions of the construction and maintenance dramatically degrades their solidity, corroding-, shiftingand frost-resistance, and ultimately – the service durability. The source of deformation processes is the character of the gradient temperature fields in the road dressing materials developing with both protracted (static and short run (dynamic heat-and-mass impacts that forward destruction of the pavement surface layers being in contact with free air. In addition, pulsating hydrodynamic pressures appear in the pores of moisture-laden pavement as a result of the vehicular traffic that foster material structure disruption of the surface layers leading to irreversible deformation incipiency (cracks etc.. The authors report of developing a С++ computer program for temperature and gradient fields engineering evaluations of the road dressings made of materials with various surfacing and free-air thermophysical characteristics in line with boundary conditions of the 3rd kind for semi-bounded body. The paper presents the evaluation results in form of graphical curves of the temperature allocation along the surfacing thickness as function of its initial temperature and thermophysical characteristics of the concrete

  14. 投稿须知%Construction Technology for Fast-Track Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In this paper, one of new contents: construction technology for fast-track concrete pavement is introduced in 《Technical Specification for Construction of Highway Cement Concrete Pavements》 (JTG F30) which is revised in 2010 in order to not only provide high-quality and long-lasting life, but also reduce the time of engineering in the new construction, reconstruction and resurfacing maintain of cement concrete pavements, to quickly and early open public traffic, and to reduce traffic interruptions.

  15. The Dependence of Physical Mechanical Properties of Concrete Pavement Blocks on Coarse Aggregate Type

    Directory of Open Access Journals (Sweden)

    Malaiškienė Jurgita

    2014-12-01

    Full Text Available The aim of this research is to determine the dependences of the physical mechanical properties of vibropressed concrete (pavement blocks on the type of coarse aggregate used in the main layer. Sustainability of concrete pavement blocks is a really important matter. Five different batches of pavement blocks were produced, changing the consistence ratio of coarse aggregate in the main layer. There are two types of course aggregate: crushed gravel and granite. The consistence of a facing layer was not changed. All tests: density, tensile split strength, water absorption for vibro-pressed concrete units were made according to EN 1338:2003+AC2006.

  16. Modelling of Mechanical Properties of Cement Concrete Incorporating Reclaimed Asphalt Pavement

    OpenAIRE

    MATHIAS, Vincent; SEDRAN, Thierry; De Larrard, François

    2009-01-01

    In many countries there is a trend to recycle wastes obtained during pavement maintenance or reconstruction, and to forbid the landfill of these products. Thus, in some circumstances it can be tempting to use reclaimed asphalt pavement (RAP) in new hydraulic concrete mixtures. This paper presents experimental data and modelling about the effect of RAP incorporation on cement concrete mechanical properties (compressive strength, tensile strengths and E-modulus). All these properties tend to de...

  17. Integration and road tests of a self-sensing CNT concrete pavement system for traffic detection

    International Nuclear Information System (INIS)

    In this paper, a self-sensing carbon nanotube (CNT) concrete pavement system for traffic detection is proposed and tested in a roadway. Pre-cast and cast-in-place self-sensing CNT concrete sensors were simultaneously integrated into a controlled pavement test section at the Minnesota Road Research Facility (MnROAD), USA. Road tests of the system were conducted by using an MnROAD five-axle semi-trailer tractor truck and a van, respectively, both in the winter and summer. Test results show that the proposed self-sensing pavement system can accurately detect the passing of different vehicles under different vehicular speeds and test environments. These findings indicate that the developed self-sensing CNT concrete pavement system can achieve real-time vehicle flow detection with a high detection rate and a low false-alarm rate. (paper)

  18. Integration and road tests of a self-sensing CNT concrete pavement system for traffic detection

    Science.gov (United States)

    Han, Baoguo; Zhang, Kun; Burnham, Tom; Kwon, Eil; Yu, Xun

    2013-01-01

    In this paper, a self-sensing carbon nanotube (CNT) concrete pavement system for traffic detection is proposed and tested in a roadway. Pre-cast and cast-in-place self-sensing CNT concrete sensors were simultaneously integrated into a controlled pavement test section at the Minnesota Road Research Facility (MnROAD), USA. Road tests of the system were conducted by using an MnROAD five-axle semi-trailer tractor truck and a van, respectively, both in the winter and summer. Test results show that the proposed self-sensing pavement system can accurately detect the passing of different vehicles under different vehicular speeds and test environments. These findings indicate that the developed self-sensing CNT concrete pavement system can achieve real-time vehicle flow detection with a high detection rate and a low false-alarm rate.

  19. The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China.

    Science.gov (United States)

    Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

    2016-01-01

    This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO₂e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO₂e is 8215.31 tons. Based on the evaluation results, the CO₂e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO₂e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO₂e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO₂ in each phase, which accounts for more than 98% of total emissions. N₂O and CH₄ emissions are relatively insignificant. PMID:27347987

  20. The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China

    Science.gov (United States)

    Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

    2016-01-01

    This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO2e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO2e is 8215.31 tons. Based on the evaluation results, the CO2e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO2e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO2e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO2 in each phase, which accounts for more than 98% of total emissions. N2O and CH4 emissions are relatively insignificant. PMID:27347987

  1. The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China.

    Science.gov (United States)

    Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

    2016-06-24

    This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO₂e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO₂e is 8215.31 tons. Based on the evaluation results, the CO₂e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO₂e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO₂e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO₂ in each phase, which accounts for more than 98% of total emissions. N₂O and CH₄ emissions are relatively insignificant.

  2. How to transform an asphalt concrete pavement into a solar turbine

    International Nuclear Information System (INIS)

    Highlights: • We create a system for harvesting energy from asphalt concrete. • We create an artificial porosity in the asphalt concrete. • We connect a chimney to this porosity. • Differences in temperature produce an air flow. • This air flow serves also for cooling down the pavement. - Abstract: Asphalt concrete can absorb a considerable amount of the incident solar radiation. For this reason asphalt roads could be used as solar collectors. There have been different attempts to achieve this goal. All of them have been done by integrating pipes conducting liquid, through the structure of the asphalt concrete. The problem of this system is that all pipes need to be interconnected: if one is broken, the liquid will come out and damage the asphalt concrete. To overcome these limitations, in this article, an alternative concept is proposed:parallel air conduits, where air can circulate will be integrated in the pavement structure. The idea is to connect these artificial pore volumes in the pavement to an updraft or to a downdraft chimney. Differences of temperature between the pavement and the environment can be used to create an air flow, which would allow wind turbines to produce an amount of energy and that would cool the pavement down in summer or even warm it up in winter. To demonstrate that this is possible, an asphalt concrete prototype has been created and basics calculations on the parameters affecting the system have been done. It has been found that different temperatures, volumes of air inside the asphalt and the difference of temperature between the asphalt concrete and the environment are critical to maximize the air flow through the pavement. Moreover, it has been found that this system can be also used to reduce the heat island effect

  3. Synthesis Study on Use of Concrete Recycled from Pavement and Building Rubble in the Indiana Highway System

    OpenAIRE

    Burke, Thomas T.; Cohen, Menashi D.; Scholer, Charles F.

    1992-01-01

    The demolition of buildings and highway pavements in the State of Indiana generates a considerable amount of waste materials. The disposal of these materials causes strain on the existing landfills which are rapidly approaching their full capacity. This study is a synthesis of the information on the use of concrete recycled from pavements and building rubble for use in the Indiana highway system. Test results have shown that recycled pavement concrete made chiefly from broken-up and crushed o...

  4. Performance polymeric concrete with synthetic fiber reinforcement against reflective cracking in rigid pavement overlay

    International Nuclear Information System (INIS)

    Cement concrete pavements are used for heavy traffic loads throughout the world owing to its better and economical performance. Placing of a concrete overlay on the existing pavement is the most prevalent rehabilitating method for such pavements, however, the problem associated with the newly placed overlay is the occurrence of reflective cracking. This paper presents an assessment of the performance of polymeric concrete with synthetic fiber reinforcement against reflective cracking in an overlay system. The performance of polymeric concrete with synthetic fibers as an overlay material is measured in terms of the load-deflection, strain-deflection and load-strain behavior of beams of the polymeric concrete. For this purpose, five types of beams having different number of fiber wires and position are tested for flexure strength. Deflection/strains for each increment of load are recorded. In addition, cubes of plain concrete and of concrete with synthetic fiber needles were tested after 7 and 28 days for compressive strengths. Finite element models in ANSYS software for the beams have also been developed. Beams with greater number of longitudinal fiber wires displayed relatively better performance against deflection whilst beams with synthetic fiber needles showed better performance against strains. Thus, polymeric concrete overlay with fiber reinforcement will serve relatively better against occurrence of reflective cracking. (author)

  5. Permanent Deformation of Asphalt Concrete Pavements: A Nonlinear Viscoelastic Approach to Mix Analyses and Design

    OpenAIRE

    Long, Fenella Margare

    2001-01-01

    Because pavements are being subjected to increasingly heavy loads, many mix design procedures currently in use may not adequately prevent permanent deformation (rutting) in asphalt concrete. This dissertation describes the development of a nonlinear viscoelastic constitutive model that can be used in mix analyses to design rut-resistant mixes. Shear deformation is the dominant cause of rutting in asphalt concrete, a nonlinear viscoelastic material. To determine the viscoelastic shear...

  6. The design and analysis on asphalt concrete pavement%沥青混凝土路面设计分析

    Institute of Scientific and Technical Information of China (English)

    王星茹

    2016-01-01

    This paper introduced the design process of urban road asphalt pavement,discussed the material and type of asphalt concrete pave-ment,from the pavement structure combination design,pavement design index,pavement structure layer calculation and other aspects,elabora-ted the design method of asphalt concrete pavement,made the asphalt pavement meet the structure strength and stability requirements.%介绍了城市道路沥青路面设计的流程,论述了沥青混凝土面层的材料与类型,从路面结构组合设计、路面设计指标、路面结构层计算等方面,阐述了沥青混凝土路面的设计方法,使沥青路面满足结构强度和稳定性的要求.

  7. Photocatalyticpaving concrete

    Directory of Open Access Journals (Sweden)

    Lyapidevskaya Ol'ga Borisovna

    2014-02-01

    Full Text Available Today bituminous concrete is a conventional paving material. Among its advantages one can name dustlessness and noiselessness, fine wear (up to 1 mm a year and fine maintainability. As the main disadvantages of this material one can name high slipperiness under humidification, low durability and weather resistance. Besides that, during placement of the bituminous concrete a lot of different air pollutants are emitted, which are harmful for environment and human’s health (they are listed in the paper according to the US Environmental Protection Agency materials. As an alternative, one can use cement-concrete pavement, which is in many ways more efficient than the bituminous concrete. It is proposed to enhance environmental performance of the cement-concrete pavement via usage of photocatalysis. The mechanism of different photocatalytic reactions is described in the paper, namely heterogeneous and homogeneous photocatalysis, photo-induces, photoactivated catalysis and catalytical photoreactions. It is pro-posed to use heterogeneous photocatalysis with titanium dioxide as a photocatalyst. The mechanism of photo oxidation of air contaminants, with the usage of titanium dioxide is2described. The paper sets problems, connected with the sensibilization of TiOto thevisible light (it is proposed to use titanium dioxide, doped with the atoms of certain elements to increase its sensibility to the visible light and with the development of a new photocatalytic paving concrete, which will meet the requirements, specified for paving in the climatic and traffic conditions of the Russian Federation.

  8. Sound Absorption and Friction Properties of Nano-Lotus Leaf Coated Concrete for Rigid Pavement

    Directory of Open Access Journals (Sweden)

    Marcelo GONZALEZ

    2016-09-01

    Full Text Available This paper presents the feasibility of superhydrophobic films to create the nano-lotus leaf effect on concrete surface and their influence on sound absorption and friction properties of concrete for application in rigid pavements. The study involved an evaluation of nanomaterials at the laboratory scale to analyze the effects of microtexture modification on the friction and sound absorption of concrete pavement. A number of laboratory specimens were produced by applying different amounts of nano-lotus leaf coating on the top of the textured concrete surface. The British pendulum test was used to measure the friction number, and an impedance tube was used to determine the sound absorption coefficient. Laboratory results indicate that nano-lotus leaf coated concrete can maintain the required friction property for rigid pavement, but may not increase the noise absorption. Further research must be carried out to determine possible benefit of the lotus leaf effect for reducing hydroplaning, particularly during heavy rainfall.DOI: http://dx.doi.org/10.5755/j01.ms.22.3.7638

  9. Numerical Simulation of Moving Load on Concrete Pavements

    Directory of Open Access Journals (Sweden)

    Lajčáková Gabriela

    2015-06-01

    Full Text Available The knowledge of the development with time of the strain and stress states in pavement structures is needed in the solution of various engineering tasks as the design fatigue lifetime reliability maintenance and structure development. The space computing model of the truck TATRA 815 is introduced. The pavement computing model is created in the sense of Kirchhof theory of the thin slab on elastic foundation. The goal of the calculation is to obtain the vertical deflection in the middle of the slab and the time courses of vertical tire forces. The equations of motion are derived in the form of differential equations. The assumption about the shape of the slab deflection area is adopted. The equations of the motion are solved numerically in the environment of program system MATLAB. The dependences following the influence of various parameters (speed of vehicle motion, stiffness of subgrade, slab thickness, road profile on the pavement vertical deflections and the vertical tire forces are introduced. The results obtained from the plate computing model are compared with the results obtained by the FEM analysis. The outputs of the numerical solution in the time domain can be transformed into a frequency domain and subsequently used to solve various engineering tasks.

  10. Modelling of composite concrete block pavement systems applying a cohesive zone model

    DEFF Research Database (Denmark)

    Skar, Asmus; Poulsen, Peter Noe

    This paper presents a numerical analysis of the fracture behaviour of the cement bound base material in composite concrete block pavement systems, using a cohesive zone model. The functionality of the proposed model is tested on experimental and numerical investigations of beam bending tests...... that the cohesive model is suitable for simulation of crack propagation in cement bound materials subjected to monotonic loading. The methodology implemented gives a new understanding of the mechanical behaviour of cement bound materials which can be used in further refinements of mechanical models for composite...... block pavements. It is envisaged that the methodology implemented in this study can be extended and thereby contribute to the ongoing development of rational failure criteria that can replace the empirical formulas currently used in pavement engineering....

  11. Using Recycled Glass and Zeolite in Concrete Pavement to Mitigate Heat Island and Reduce Thermal Cracks

    Directory of Open Access Journals (Sweden)

    Erhan Burak Pancar

    2016-01-01

    Full Text Available Urban heat island (UHI effect is built environmental issue related to pavements. It is desired to reduce pavement high surface temperature in summer to mitigate UHI effect. High surface temperature also affects slab temperature difference (the top surface temperature minus the bottom surface temperature of the slab. The increased slab temperature difference induces a high possibility of cracking in concrete roads. The prime aim of this study was to reduce the slab surface temperature by using recycled glass as a fine aggregate and zeolite as cement in concrete. Recycled glass was used to replace fine aggregate in proportions of 10%, 20%, and 30% by total weight of aggregate. Zeolite replaced Portland cement in proportions of 10% and 30% for three different proportions of recycled glass concrete mixtures. Optimum proportions were determined by examining mechanical properties of samples and alkali-silica reactions. It was noticed that using recycled glass and zeolite together in concrete reduces pavement surface temperature and temperature gradient in summer.

  12. Factors affecting the deterioration of concrete pavement slabs

    Directory of Open Access Journals (Sweden)

    N.M. Morozov

    2015-11-01

    Full Text Available The behavior of constructions under actual operating conditions is affected by exposure to the environment. It is important that concrete roads and airport pavings are resistant not only to mechanical damage, but also to the effects of alternate freezing and thawing. The causes of early failure in concrete have been shown using prefabricated road slabs as an example. The causes of loss of performance properties of the roadway have been established, which are primarily dependent on the quality of raw materials in the concrete. It was found that, aside from durability, uniformity and porosity are important factors in determining the frost resistance of concrete roadways. It was shown that high aluminate content in the cement leads to concrete destruction in the first year of structure use. The results may also indirectly indicate a violation of forming technology during slab production.

  13. A Simple Field Test to Evaluate the Maintenance Requirements of Permeable Interlocking Concrete Pavements

    OpenAIRE

    Terry Lucke; Richard White; Peter Nichols; Sönke Borgwardt

    2015-01-01

    Adequate infiltration through Permeable Interlocking Concrete Pavements (PICPs) is critical to their hydraulic and stormwater treatment performance. Infiltration is affected by clogging caused by the trapping of fines in the PICP surface, which, over time, reduces treatment performance. Clogging can be reduced by periodic maintenance such as vacuum sweeping and/or pressure washing. Maintenance requirements can be indicated by measuring reduced infiltration rates. This paper compared infiltrat...

  14. Studies on Scrap Tyre Added Concrete for Rigid Pavements

    Directory of Open Access Journals (Sweden)

    Eldhose C.

    2014-12-01

    Full Text Available Waste tyre treatment is now global threat. Waste tyre dumping, disposal of these materials or burning these tyres cause serious environmental and health problems. This paper investigate the wide range of physical and mechanical properties of concrete containing waste tyre aggregates and assess its suitability as a construction material. Waste tyres are powdered into fine particles of various sizes and are used to replace the fine aggregate used in concrete. The fine scrap tyre aggregate is added as 2%, 4%, 6%, 10%, and 12% increment to replace the fine aggregate. This study aims to investigate the optimal use of waste tyre aggregates as fine aggregate in concrete composite.

  15. Predicting the behavior of asphalt concrete pavements in seasonal frost areas using nondestructive techniques

    Science.gov (United States)

    Janoo, Vincent C.; Berg, Richard L.

    1990-11-01

    Four different pavement test sections were subjected to freeze-thaw cycling in the Frost Effects Research Facility (FERF). The test sections, each 610 cm in length, consisted of 15.2 cm of asphalt concrete pavement over a clay subgrade; 15.2 cm of asphalt concrete over 10.2 cm of crushed gravel over a clay subgrade; 5.1 cm of asphalt over 17.8 cm of crushed gravel over 20.3 cm of clean sand over a clay subgrade; and 5.1 cm of asphalt concrete over 25.4 cm of crushed gravel over 12.7 cm of clean sand over clay subgrade. Thermocouples were imbedded throughout the pavement structure and subgrade. During the thawing periods, deflection measurements were made at four locations in each test section using a Dynatest Falling Weight Deflectometer (FWD). The results of the deflection measurement are presented here. An analysis was done to qualify the subgrade strength based solely on FDW measurements. It was also shown that a relationship existed between thaw depth and FWD measurement in the subgrade.

  16. Studies on Scrap Tyre Added Concrete for Rigid Pavements

    OpenAIRE

    Eldhose C.; Dr. Soosan T. G

    2014-01-01

    Waste tyre treatment is now global threat. Waste tyre dumping, disposal of these materials or burning these tyres cause serious environmental and health problems. This paper investigate the wide range of physical and mechanical properties of concrete containing waste tyre aggregates and assess its suitability as a construction material. Waste tyres are powdered into fine particles of various sizes and are used to replace the fine aggregate used in concrete. The fine scrap...

  17. Development Of Optimum Maintenance amp Rehabilitation Strategies For Urban Bituminous Concrete Surfaced Roads

    Directory of Open Access Journals (Sweden)

    Dr Pardeep Kumar Gupta

    2015-02-01

    Full Text Available ABSTRACT In India the road traffic volume has increased manifolds during the post-independence period. The traffic axle loading may also in many cases be much heavier than the specified limit. As a result of which the existing road network has been subjected to severe deterioration leading to premature failure of the pavements.In such a scenario development of the effective pavement management strategies would furnish useful information to ensure the compatible and cost- effective decisions so as to keep the existing road network intact. The pavement deterioration models can prove to be an effective tool which can assist highway agencies to forecast economic and technical outcome of possible investment decisions regarding maintenance management of pavements. The optimum maintenance and rehabilitation strategies developed in this study would be useful in planning pavement maintenance strategies in a scientific manner and ensuring rational utilization of limited maintenance funds. Once this strategy for urban road network is implemented and made operational this would serve as window to the other urban road network of different regions.

  18. 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.

  19. 水泥混凝土路面裂缝成因及预防措施%Cause and prevention measure of cement concrete pavement crack

    Institute of Scientific and Technical Information of China (English)

    罗永明

    2009-01-01

    Combining with the wide application of the cement concrete pavement, the author analyzes the causes of cement concrete pavement crack, provides prevention measures of cement concrete pavement crack, so as to perform construction technology of the cement concrete pave-ment, improve quality of the cement concrete pavement, and prolong service life to the pavement.%结合水泥混凝土路面的广泛应用,分析了水泥混凝土路面裂缝的原因,提出了水泥混凝土路面裂缝的预防措施,以完善水泥混凝土路面施工工艺,提高水泥混凝土路面的质量,延长路面的寿命.

  20. Cement treated recycled crushed concrete and masonry aggregates for pavements

    NARCIS (Netherlands)

    Xuan, D.X.

    2012-01-01

    This research is focusing on the characterization of the mechanical and deformation properties of cement treated mixtures made of recycled concrete and masonry aggregates (CTMiGr) in relation to their mixture variables. An extensive laboratory investigation was carried out, in which the mechanical p

  1. Cement treated recycled crushed concrete and masonry aggregates for pavements

    OpenAIRE

    Xuan, D.X.

    2012-01-01

    This research is focusing on the characterization of the mechanical and deformation properties of cement treated mixtures made of recycled concrete and masonry aggregates (CTMiGr) in relation to their mixture variables. An extensive laboratory investigation was carried out, in which the mechanical properties of CTMiGr and the deformation characteristics relevant to shrinkage crack susceptibility were evaluated. The main aim of this research is to develop models which allow the structural prop...

  2. Laboratory evaluation of porous concrete for use as low traffic road pavement material

    Energy Technology Data Exchange (ETDEWEB)

    Pribadi, K.S.; Tamin, P.F.

    1999-12-16

    A research on the properties of porous concrete mixes has been conducted. Porous concrete is ordinary concrete with very high air void content, with a particular property that water can percolated easily through it. It makes an appropriate draining pavement material. Specimens with various compaction methods and sand contents were prepared using coarse aggregates obtained from Banjaran area and fine aggregates from Galunggung volcanic sediment. Effective mixes with high compressive strength up to 23 MPa and percolation rate of 200 mm/min were obtained at 20% sand content for heavily compacted samples. Flexural strengths ranging from 1.95 MPa up to 5.8 MPa for heavily compacted specimens with 10% sand content have been obtained. Failure loading repetitions during fatigue tests on heavily compacted specimens ranging from 2.835 cycles at 0.95% stress ratio up to 405.815 cycles at 0.70% stress ratio have been recorded. (author)

  3. Investigation of Primary Causes of Load-Related Cracking in Asphalt Concrete Pavement in North Carolina

    Science.gov (United States)

    Park, Hong Joon

    This dissertation presents causes of cracking in asphalt concrete pavement in North Carolina through field investigation and laboratory experiments with field extracted material. North Carolina is experiencing higher than anticipated rates of fatigue cracking compared to other state. These higher than expected rates could be reflective of the national trends in mix design practice or could be caused by structural pavement failures. The problems associated with premature cracking in North Carolina pavements point to the need to evaluate the North Carolina Department of Transportation (NCDOT) mixes, processes, and measures to ensure that these factors properly balance the goals of preventing cracking and minimizing permanent deformation. Without solid data from in-service pavements, any conclusions regarding the causes of these failures might be pure conjecture. Accordingly, this research examines material properties through laboratory experiments using field-extracted materials and investigates in situ pavements and pavement structure. In order to assess condition of existing pavement, alligator cracking index (ACI) was developed. The asphalt content in the top layer that exhibits top-down cracking or bottom-up cracking has a proportional relationship to ACI values. The air void content in a bottom layer that exhibits top-down cracking or bottom-up cracking shows an inverse proportional relationship to ACI values. These observations reflect reasonable results. A comparison between ACI and asphalt film thickness values does not produce noteworthy findings, but somewhat reasonable results are evident once the range of comparison is narrowed down. Thicker film thicknesses show higher ACI values. From field core visual observations, road widening is identified as a major cause of longitudinal cracking. Regions with observed layer interface separation tend to have low ACI values. Through tensile strain simulation based on actual field conditions, it is observed that

  4. Heterogeneous Photocatalysis Applied to Concrete Pavement for Air Remediation

    Science.gov (United States)

    Ballari, M. M.; Hunger, M.; Hüsken, G.; Brouwers, H. J. H.

    In the present work the degradation of nitrogen oxides (NOx) by concrete paving stones containing TiO2 to be applied in road construction is studied. A kinetic model is proposed to describe the photocatalytic reaction of nitric oxide (NO) in a standard flow laminar photoreactor irradiated with UV lamps. In addition the influence of several parameters that can affect the performance of these stones under outdoor conditions are investigated, such as irradiance, relative humidity and wind speed. The kinetic parameters present in the NO reaction rate are estimated employing experimental data obtained in the photoreactor. The obtained model predictions employing the determined kinetic constants are in good agreement with the experimental results of NO concentration at the reactor outlet.

  5. HOW TO OBTAIN ECONOMICALLY EFFICIENT ASPHALT CONCRETE MIXTURES FOR CONSTRUCTIVE AUTOMOBILE ROAD AND STREET PAVEMENTS

    Directory of Open Access Journals (Sweden)

    V. A. Verenko

    2009-01-01

    Full Text Available The paper describes a methodology for evaluation of technical and economic efficiency of asphalt concrete mixture components. The method allows to perform a directed search for new materials which are used for mixture preparation and it also provides an efficient use of monetary funds. Firstly, it is possible to obtain this result due to optimum price-quality ratio of asphalt mixture which is determined by its service life in a pavement; secondly, it is possible to obtain this result due to  exclusion of errors while selecting components of the asphalt mixture out of the whole range applied presently in the world practice.

  6. Pavement structure mechanics response of flexible on semi-flexible overlay that based on the old cement concrete pavement damage

    Directory of Open Access Journals (Sweden)

    Jiang Ruinan

    2015-01-01

    Full Text Available The old cement pavement damage status directly affect the design of the paving renovation. Based on the state of the old road investigation, combined with the research data at home and abroad, use the control index that average deflection, deflection value and CBR value to determine the reasonable time to overlay. Draw up the typical pavement structure according to the principle of combination of old cement pavement overlay structure design, and calculated that the tensile stress and shear stress in asphalt layer ,semi-flexible layer and the tensile in the old cement pavement adopting BISA3.0 statics finite element analysis model when modulus in the old road was diminishing. Use the computed result to analyses the influence of old road damage condition the influence of pavement structure.

  7. Use of accelerated aging to predict behavior of recycled materials in concrete pavements. Physical and environmental comparison of laboratory-aged samples with field pavements

    Energy Technology Data Exchange (ETDEWEB)

    Van der Sloot, H.A. [ECN Clean Fossil Fuels, Petten (Netherlands); Eighmy, T.T.; Cook, R.A.; Gress, D.L.; Coviello, A.; Spear, J.C.M. [University of New Hampshire, Durham, NH (United States); Hover, K.; Pinto, R.; Hobbs, S. [Cornell University, Ithaca, NY (United States); Kosson, D.S.; Sanchez, F. [Vanderbilt University, Nashville, TN (United States); Korhonen, C. [US Army Corps of Engineers Cold Regions Research and Engineering Laboratory, Hanover, NH (United States); Simon, M. [Turner-Fairbank Highway Research Center, McLean, VA (United States)

    2002-11-01

    Future behavior of recycled materials in highway applications is often difficult to predict. Accelerated aging is one means of exploring the long-term physical and environmental performance. Coal fly ash (CFA), routinely used as a cementitious replacement in portland cement concrete pavement, was selected as a model system in an accelerated aging approach. US-20 near Fort Dodge, Iowa, was used as a source of field-aged pavement slab material and concrete mixture proportions. This pavement, constructed in 1987, experienced early failure and distress. The role of CFA, if any, in the failure is not known. Three types of accelerated aging treatments were chosen and applied on laboratory prisms made with the US-20 mixture proportions: arrhenius ageing (AA), cyclic loading, and freeze-thaw exposure. Physical and environmental response variables were used to examine the pavement slab and the aged laboratory prisms. The aging protocol affected both physical and chemical properties of the monoliths. It took about 9 months of elapsed time to age specimens to an equivalent age of about 4 years. The equivalent ages matched well with the time frame seen in the field for the onset of early distress. Most response variables for the aged laboratory prisms and the field samples were similar, suggesting that the aging method reasonably produced a pavement of similar age and distress. The AA treatment produced an unexpected loss of strength, suggesting that the accelerated aging promoted the onset of a deleterious reaction. Distinguishing the source of trace metals in leachates was difficult, for all components (CFA, aggregates, cement) had similar elemental compositions and leachability. The use of both physical and environmental response variables showed linkages between compressive strength, microcracking, fine pore structure, Cl diffusive leaching (efflux related to road slating that increases the concentration of Cl in the monolith), and Ca diffusive leaching (related to change

  8. Integration of a prototype wireless communication system with micro-electromechanical temperature and humidity sensor for concrete pavement health monitoring

    Directory of Open Access Journals (Sweden)

    Shuo Yang

    2015-12-01

    Full Text Available In recent years, structural health monitoring and management (SHMM has become a popular approach and is considered essential for achieving well-performing, long-lasting, sustainable transportation infrastructure systems. Key requirements in ideal SHMM of road infrastructure include long-term, continuous, and real-time monitoring of pavement response and performance under various pavement geometry-materials-loading configurations and environmental conditions. With advancements in wireless technologies, integration of wireless communications into sensing device is considered an alternate and superior solution to existing time- and labor-intensive wired sensing systems in meeting the requirements of an ideal SHMM. This study explored the development and integration of a wireless communications sub-system into a commercial off-the-shelf micro-electromechanical sensor-based concrete pavement monitoring system. A success-rate test was performed after the wireless transmission system was buried in the concrete slab, and the test results indicated that the system was able to provide reliable communications at a distance of more than 46 m (150 feet. This will be a useful feature for highway engineers performing routine pavement scans from the pavement shoulder without the need for traffic control or road closure.

  9. Laboratory analysis of the infiltration capacity of interlocking concrete block pavements in car parks.

    Science.gov (United States)

    Sañudo-Fontaneda, Luis A; Rodriguez-Hernandez, Jorge; Vega-Zamanillo, Angel; Castro-Fresno, Daniel

    2013-01-01

    Interlocking concrete block pavements (ICBPs) have been widely used in car parks to reduce runoff. Researches have demonstrated that clogging is the most influential factor in the reduction of the infiltration capacity of this type of permeable pavement. Nevertheless, there is no laboratory study of the infiltration performance of ICBPs that combines clogging levels with variables related with the topography of car parks such as runoff surface length (R(SL)) and surface slope (S(S)). This paper studies the infiltration behaviour of ICBP during their operational life in a car park using an improved version of the Cantabrian Fixed (CF) Infiltrometer. This laboratory device simulates direct rainfall and runoff from adjacent impervious areas over an ICBPs surface of 0.25 m(2) for different slopes (0, 3, 5, 7 and 10%) and three scenarios of clogging (surface newly built, surface clogged and surface clogged with maintenance). This paper presents the results of the tests and a statistical analysis based on three regression models (corresponding to each clogging scenario) depending on the R(SL) and S(S) variables. All models passed a confidence level of 95%, presenting high R(2) values and showing that R(SL) is a more influential variable than the S(S) for all clogging scenarios.

  10. 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.

  11. Three-dimensional Finite Element Analysis on the Layer Steel Fiber Reinforced Concrete Pavement:A New Type of Pavement Material

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An investigation was conducted on the design of layer steel fiber reinforced concrete (LSFRC) pavement.Finite element method was applied to the analysis on the stress distribution in order to determine the thickness and segregation distance of LSFRC pavement slabs.

  12. 露石水泥混凝土路面耐久性的研究%Study on Durability of the Exposed-aggregate Cement Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    邹涛; 王欣

    2015-01-01

    Exposed-aggregate cement concrete pavement is a new road,the durability is the key issue of concrete pavement development.The article studies the durability of exposed-aggregate cement concrete pavement from carbon-ation resistance,salt freezing erosion,abrasion and so on.The results showed that:the carbonation depth of the ex-posed aggregate cement concrete pavement was larger than the ordinary cement concrete pavement,indicating its poor carbonation resistance;at the same time,the exposed-aggregate cement concrete pavement was poorer than the ordina-ry cement concrete pavement on frost resistance,salt erosion.But the abrasion resistance of exposed-aggregate cement concrete was much larger than the ordinary cement concrete pavement.%露石水泥混凝土路面是一种新型路面,混凝土的耐久性是影响混凝土路面发展的关键问题。论文从抗碳化性能、抗盐冻剥蚀、耐磨性等三个方面研究露石水泥混凝土路面的耐久性。研究结果表明:露石水泥混凝土路面的碳化深度要比普通水泥混凝土路面大,表明其抗碳化性能比普通水泥混凝土差;同时露石水泥混凝土的抗冻性、抗盐剥蚀也比普通水泥混凝土路面差;但是露石水泥混凝土的耐磨性要远大于普通水泥混凝土路面。

  13. Permeability measurement and scan imaging to assess clogging of pervious concrete pavements in parking lots.

    Science.gov (United States)

    Kayhanian, Masoud; Anderson, Dane; Harvey, John T; Jones, David; Muhunthan, Balasingam

    2012-03-01

    This paper describes a study that used permeability measurement along with physical and hydrological characteristics of 20 pervious concrete pavements in parking lots throughout California. The permeability was measured at five locations: the main entrance, an area with no traffic, and three separate measurements within a parking space at each parking lot. Hydrological and physical site characteristics such as traffic flow, erosion, vegetation cover, sediments accumulation, maintenance practice, presence of cracking, rainfall, and temperature data were also collected for each parking lot. These data were used to perform detailed statistical analysis to determine factors influencing changes in permeability and hence assessing possible cause of clogging. In addition, seven representative core samples were obtained from four different parking lots with permeability ranging from very low to very high. Porosity profiles produced from CT scanning were used to assess the possible nature and extent of clogging. Results showed that there is a large variation in permeability within each parking lot and between different parking lots. In general, the age of the parking lot is the predominant factor influencing the permeability. Statistical analysis revealed that fine sediment (particles less than 38 μm) mass is also an important influencing factor. Other influencing factors with lower significance included number of days with a temperature greater than 30°C and the amount of vegetation next to the parking lot. The combined scanned image analysis and porosity profile of the cores showed that most clogging occurs near the surface of the pavement. While lower porosity generally appeared to be limited to the upper 25 mm, in some core samples evidence of lower porosity was found up to 100mm below the surface. PMID:22115516

  14. 橡胶沥青混凝土路面施工技术研究%Research on construction technology of rubber asphalt concrete pavement

    Institute of Scientific and Technical Information of China (English)

    李霞

    2015-01-01

    对传统路面与橡胶混凝土路面的性价比进行了分析比较,介绍了橡胶沥青混凝土路面的特点,并对其在工程中的应用技术进行了阐述,指出橡胶沥青混凝土路面具有显著的经济、社会、环境效益,应用前景广阔。%This paper analyzed and compared the cost performance of traditional pavement and rubber concrete pavement, introduced the charac-teristics of rubber asphalt concrete pavement, and elaborated its application technology in engineering, pointed out that the rubber asphalt con-crete pavement had significant economic, social, environmental benefits, had wide application prospect.

  15. About the sizes of elastomer particles in the asphalt concrete binder providing the maximum service life of pavements

    Science.gov (United States)

    Kaplan, A. M.; Chekunaev, N. I.

    2014-05-01

    It is noted that the durability of asphalt concrete pavements is determined by the time of the trunk cracks formation in the polymer-containing composites - in the modified by elastomers (e.g., by rubber) bitumenous binder of asphalt. Developed by the authors previously the theory of the cracks propagation in heterosystems [1] has allowed to investigate the problem of the cracks propagation in the rubber-bitumen composite. This investigations show that most effectively to prevente the trunk cracks formation in asphalt concrete can ultrafine rubber particles (150-750 nm) in a bitumenos binder of asphalt.

  16. Alkali-silica reaction of aggregates for concrete pavements in Chihuahua’s State, Mexico

    Directory of Open Access Journals (Sweden)

    Olague, C.

    2002-12-01

    Full Text Available The concrete of pavements must resist the climatic conditions, heavy traffic, chemical agents or any other type of aggressive agent. A methodology for characterizing materials that would influence concrete durability was developed considering chemical and physical factors. This methodology allows the consideration of several factors like physiography, geology, and climate, among others that would be of great importance to prevent future durability problems of pavements. This methodology takes into account several tests and this paper presents the results of potential reactivity aggregates of the State of Chihuahua. The tests for evaluating the reactive siliceous aggregate and the potential alkali-silica reactivity were performed according to the: petrographic examination (ASTM C 295 and standard quick chemical test (ASTM C 289. 38% of the tested sites resulted innocuous, 48% potentially reactive and 13% reactive. It is discussed the benefit of applying a conscious methodology in order to obtain the best results with a representative quantity of tests.

    El hormigón de los pavimentos debe ser resistente a las condiciones climáticas, tránsito pesado, agentes químicos o cualquier otro tipo de agente agresivo. Se desarrolló una metodología para caracterización de materiales considerando factores físicos y químicos que influyen en la durabilidad del hormigón. Esta metodología se basa en la consideración de varios factores como: fisiografía, geología y clima, entre otros, que podrían ser de gran importancia para prevenir futuros problemas de durabilidad en pavimentos de hormigón. La metodología en cuestión considera varias pruebas, en este artículo se presentan los resultados de la reactividad potencial de los áridos del Estado de Chihuahua. Las pruebas para evaluar la reactividad de áridos silíceos y la reactividad potencial álcali-sílice fueron ejecutadas de acuerdo a: examen petrográfico (ASTM C 295 y la prueba qu

  17. Application of Old Cement Concrete Pavement in Steel Fiber Reinforced Concrete Surface Layer%浅谈旧水泥砼路面加铺钢纤维砼面层的应用

    Institute of Scientific and Technical Information of China (English)

    丁海萍; 刘妙

    2013-01-01

    Layered steel fiber concrete pavement is a new kind of pavement structure.The steel fiber is bestrewed on top and under surface of the concrete pavement plate at the time of construction,and two layers of steel fiber concrete network is formed.It can protect the position easily damaged in concrete pavement effectively,and It is important to improve bending ability of concrete pavement and reduce the thickness of concrete pavement at design time.The performance and road condition of this pavement structure is very good after consign,and pavement maintenance cost is very low.It can increase the service life of pavement greatly.The social and economic benefit is significant at the same time.%上下层布式钢纤维砼路面是一种比较新颖的路面结构.在施工的时候,在砼路面板顶面和底面上撒布钢纤维,并形成两层的钢纤维砼网.可以有效的保护砼路面容易发生破损的部位,对提升砼路面的抗弯拉能力也有很大的帮助,并能够在设计的时候,降低砼路面的厚度.这种结构的路面结构在施工交付使用后,使用的性能非常好,路面状况也很好,路面的养护和维修费用低.同时能较大提高路面的使用寿命,其社会效益、经济效益特别显著.

  18. Analysis of Factors Influencing the Asphalt Concrete Pavement Compactness%沥青混凝土路面压实度的影响因素分析

    Institute of Scientific and Technical Information of China (English)

    李彩妹

    2013-01-01

    Compactness is an important step in the construc-tion of asphalt concrete pavement compaction, it can not only ensure the pavement, improve pavement compaction smoot-hness, is also very ef ective for the lower porosity, and can effectively improve the pavement friction, has significant eff-ect on resistance against stress and crack resistance, so stud-ying on the science compaction of asphalt concrete pavement, analyzing the factors affecting the compaction degree of the concrete pavement, control ing these factors, can ef ectively improve the quality of pavement.%沥青混凝土路面施工重要的一个步骤是压实,它不但能确保路面的密实、提升路面的平整度,对降低空隙率也是非常有效果的。而且能有效提升路面摩擦力,对抵抗自然侵害力以及抗裂能力有显著的作用。所以只有研究科学的沥青混凝土路面压实,分析影响混凝土路面压实度的因素,控制好这些因素,才能有效地提高路面的质量。

  19. Experimental Analysis of Fly Ash & Coir Fiber Mix Cement Concrete for Rigid Pavement

    Directory of Open Access Journals (Sweden)

    Er. Amit Kumar Ahirwar

    2015-04-01

    Full Text Available In India Thermal power plants which use pounded coal as a fuel, generates million tones of fly ash every year as a waste. Conservative clearance of this material which gets easily air-borne and constitutes a serious health hazards to the community, is an expensive operation. A part from this compacted fly ash can be used in embankments, road sub-bases and also for structural fills. The major drawbacks of such materials are their limited load carrying capacity and poor settlement characteristics. The concert of such materials can substantially be improved by introducing reinforcing element in the direction of improving its compressive and flexural strength for superior durability. Use of natural materials such as Jute, coir and bamboo, as reinforcing materials to fly ash are very cheap and they are locally available in huge quantity, of all the natural fibers, coir has the greatest tearing strength and it retains this property even in wet conditions. In this framework a composite with fly ash, conventional concrete and treated coconut fibers, available in plenty in rural areas of India have been investigated. These composites can be a good proposition and with this, experimental investigation to study the effects of replacement of cement (by volume with different percentages of fly ash and the effects of addition of processed natural coconut fiber on flexural strength, compressive strength, splitting tensile strength and modulus of elasticity was taken up. AS per IRC, A Design mix proportion was designed for the normally popular M30 concrete for pavement construction in India. In this, Cement was replaced with percentages (10, 20, 30 and 40% of Class C fly ash and of coconut fibers (0.50 and 1.0 % having 40 mm length were used. Test results show that the replacement of 43 grades ordinary Portland cement with fly ash showed an increase in compressive strength and flexural strength for the chosen mix proportion.

  20. A study of sound absorption by street canyon boundaries and asphalt rubber concrete pavement

    Science.gov (United States)

    Drysdale, Graeme Robert

    A sound field model, based on a classical diffusion equation, is extended to account for sound absorption in a diffusion parameter used to model sound energy in a narrow street canyon. The model accounts for a single sound absorption coefficient, separate accommodation coefficients and a combination of separate absorption and accommodation coefficients from parallel canyon walls. The new expressions are compared to the original formula through numerical simulations to reveal the effect of absorption on sound diffusion. The newly established analytical formulae demonstrate satisfactory agreement with their predecessor under perfect reflection. As well, the influence of the extended diffusion parameter on normalized sound pressure levels in a narrow street canyon is in agreement with experimental data. The diffusion parameters are used to model sound energy density in a street canyon as a function of the sound absorption coefficient of the street canyon walls. The acoustic and material properties of conventional and asphalt rubber concrete (ARC) pavement are also studied to assess how the crumb rubber content influences sound absorption in street canyons. The porosity and absolute permeability of compacted specimens of asphalt rubber concrete are measured and compared to their normal and random incidence sound absorption coefficients as a function of crumb rubber content in the modified binder. Nonlinear trends are found between the sound absorption coefficients, porosity and absolute permeability of the compacted specimens and the percentage of crumb rubber in the modified binders. The cross-sectional areas of the air voids on the surfaces of the compacted specimens are measured using digital image processing techniques and a linear relationship is obtained between the average void area and crumb rubber content. The measured material properties are used to construct an empirical formula relating the average porosity, normal incidence noise reduction coefficients and

  1. 层布式钢纤维混凝土在路面改造中的应用%Layered Steel Fiber Reinforced Concrete in Pavement Reconstruction Application

    Institute of Scientific and Technical Information of China (English)

    陈如高

    2013-01-01

    阐述了层布式钢纤维混凝土路面的特点,介绍了层布式钢纤维混凝土在旧水泥路面改造中的应用,包括对旧水泥路面的处理方法、层布式钢纤维混凝土施工要点及路面改造后的效益分析。%The layer of steel fiber reinforced concrete pavement characteristics were elaborated, layered steel fiber reinforced concrete in the old concrete pavement reconstruction applications were introduced, including benefit analysis of the treatment of old cement pavement, layered steel fiber reinforced concrete construction elements and road after transformation.

  2. A Simple Field Test to Evaluate the Maintenance Requirements of Permeable Interlocking Concrete Pavements

    Directory of Open Access Journals (Sweden)

    Terry Lucke

    2015-05-01

    Full Text Available Adequate infiltration through Permeable Interlocking Concrete Pavements (PICPs is critical to their hydraulic and stormwater treatment performance. Infiltration is affected by clogging caused by the trapping of fines in the PICP surface, which, over time, reduces treatment performance. Clogging can be reduced by periodic maintenance such as vacuum sweeping and/or pressure washing. Maintenance requirements can be indicated by measuring reduced infiltration rates. This paper compared infiltration results using the standard test (C1781M-14a with the results of a new stormwater infiltration field test (SWIFT developed in Australia to evaluate the maintenance requirements of PICPs. A strong correlation (Pearson’s r = −0.714 was found between results using the two methods. This study found that the SWIFT was a reliable method for estimating the degree of clogging of PICPs while successfully overcoming some of the problems with the more technical existing test methodology such as horizontal water leakage (use of sealant, unrealistic pressure heads, speed of test, and portability. The SWIFT test is a simple, fast and inexpensive way for asset managers and local government employees to quickly assess the maintenance requirements of PICP installations in the field.

  3. 机场道面再生混凝土配制与施工%Making and construction of airport pavement recycled concrete

    Institute of Scientific and Technical Information of China (English)

    吴和胜; 刘庆涛; 陈福年; 黄庆国; 岑国平; 吴永根

    2011-01-01

    The overhauling,rebuilding and enlarging of airport pavement often produced vast waste concrete. This paper aims at how to make concrete with the waste concrete which is used as recycled aggregate, also meets the design and construction requirements of airport pavement project. By adopting the "double mixing" technique with high quality fly ash and high efficiency admixture,optimizing the mix proportion design of pavement recycled concrete. The indoor testing results show the pavement recycled concrete is superior to common pavement concrete, and the field application effect shows the recycled concrete is a new kind of green,economical concrete, can be used in airport pavement construction.%机场道面翻修、改(扩)建工程会产生大量的废弃混凝土,如何利用废弃混凝土作为再生骨料,配制道面再生混凝土,满足机场道面工程设计与施工要求,采用掺加优质粉煤灰和高效外加剂的“双掺”技术路线,进行道面再生混凝土配合比设计.室内试验表明,所配制的道面再生混凝土性能优于普通道面混凝土,现场施工实践也表明,所配制的再生混凝土可以用于机场道面工程,是一种新型绿色环保混凝土.

  4. Extending the Lifespan of Porous Asphalt Concrete

    OpenAIRE

    Zhang, Y.

    2015-01-01

    Porous Asphalt (PA) concrete is widely used as a surfacing layer on highways in the Netherlands. The service life of PA wearing courses is limited because of the fact that it is vulnerable to raveling. The possibilities of applying preventive maintenance to PA wearing courses by means of spraying rejuvenation products on the pavement surfaces are being investigated with high interest in the Netherlands. A material which has the ability to penetrate into the bituminous binder and soften (rejuv...

  5. Investigation of Self Consolidating Concrete Containing High Volume of Supplementary Cementitious Materials and Recycled Asphalt Pavement Aggregates

    Science.gov (United States)

    Patibandla, Varun chowdary

    The use of sustainable technologies such as supplementary cementitiuous materials (SCMs), and/or recycled materials is expected to positively affect the performance of concrete mixtures. However, it is important to study and qualify such mixtures and check if the required specifications of their intended application are met before they can be implemented in practice. This study presents the results of a laboratory investigation of Self Consolidating concrete (SCC) containing sustainable technologies. A total of twelve concrete mixtures were prepared with various combinations of fly ash, slag, and recycled asphalt pavement (RAP). The mixtures were divided into three groups with constant water to cementitiuous materials ratio of 0.37, and based on the RAP content; 0, 25, and 50% of coarse aggregate replaced by RAP. All mixtures were prepared to achieve a target slump flow equal to or higher than 500 mm (24in). A control mixture for each group was prepared with 100% Portland cement whereas all other mixtures were designed to have up to 70% of portland cement replaced by a combination of supplementary cementitiuous materials (SCMs) such as class C fly ash and granulated blast furnace slag. The properties of fresh concrete investigated in this study include flowability, deformability; filling capacity, and resistance to segregation. In addition, the compressive strength at 3, 14, and 28 days, the tensile strength, and the unrestrained shrinkage up to 80 days was also investigated. As expected the inclusion of the sustainable technologies affected both fresh and hardened concrete properties. Analysis of the experimental data indicated that inclusion of RAP not only reduces the ultimate strength, but it also affected the compressive strength development rate. Moreover, several mixes satisfied compressive strength requirements for pavements and bridges; those mixes included relatively high percentages of SCMs and RAP. Based on the results obtained in this study, it is not

  6. Durability of Recycled Concrete for Airport Pavement%机场道面再生混凝土的耐久性

    Institute of Scientific and Technical Information of China (English)

    刘庆涛; 吴和胜; 岑国平; 陈福年; 黄庆国; 吴永根; 朱志远

    2011-01-01

    In order to make recycled concrete that can meet the design and construction requirements of airport pavement project,the "double mixing" technique with high quality fly ash and high efficiency admixture is adopted, the frost resistances, impermeabilities and abrasion resistances of the recycled concrete are tested in laboratory. Fast freeze-thaw method is used in frost resistance test, hydrostatic pressure method and chloride penetration method are used in impermeability test, and ball bearing method is used in abrasion resistance test. The results show that the durability of the recycled concrete for airport pavement is superior to the normal pavement concrete, can meet the requirements of airport pavement,the frost resistance grade is up to F250, increases by more than 200% compared with normal pavement concrete, can fulfil the requirement of pavement in the very chilly area,and it suggests that the air capacity of the recycled concrete for pavement in the chilly area is 5%~6%, which is higher than 1% that of the normal pavement concrete; The impermeability grade by hydrostatic pressure method of the recycled concrete for pavement increases by more than 300% compared with normal pavement concrete; The abrasion resistances of the recycled concrete for pavement increases by 18%~36% compared with normal pavement concrete.%为了配制满足机场道面工程设计与施工要求的再生混凝土,采用掺加优质粉煤灰和高效外加剂的“双掺”技术路线,进行了机场道面再生混凝土的抗冻性、抗渗性和耐磨性试验研究.抗冻性试验采用快冻法,抗渗性试验采用静水压力法和氯离子渗透法,耐磨性试验采用滚珠轴承法.结果表明:所配制的道面再生混凝土耐久性能优于普通道面混凝土,能够满足机场道面要求,抗冻等级高达F250,较普通道面混凝土提高了200%以上,可以满足严寒地区道面混凝土抗冻要求,建议寒冷地区道面再生混

  7. Properties and applications of recycled concrete for airport pavement%机场道面再生混凝土的性能与应用

    Institute of Scientific and Technical Information of China (English)

    刘庆涛; 岑国平; 蔡良才; 吴永根; 吴和盛; 陈福年; 黄庆国; 朱志远

    2012-01-01

    The "double mixing" technique with high quality fly ash and high efficiency admixture was adopted. The strength, the frost resistances, impermeabilities and abrasion resistances of the recycled concrete for airport pavement were tested in laboratory, and then the recycled concrete was applied in field. The mechanism of the pavement recycled concrete's properties was studied through analyzing it's microstructure. The results show that the properties of the recycled concrete for airport pavement is superior to the normal pavement concrete, and can meet the requirements of airport pavement, the flexural strength is higher than the ordinary pavement by 4%-ll%; the frost resistance grade, which is up to F250, increasing by more than 200 % compared with normal pavement concrete, can fulfill the requirement of pavement in the very chilly area; The impermeability grade by hydrostatic pressure method of the recycled concrete for pavement increases by more than 300 % compared with normal pavement concrete; The abrasion resistances of the recycled concrete for pavement increases by 18%-36% compared with normal pavement concrete. The workability of recycled concrete made in field is well, and can be constructed expediently, with the 28-day flexural strength higher than 5.5 MPa. All the quality items meet the requirements of standard and design, and the application effect is well.%采用掺加优质粉煤灰和高效外加剂的“双掺”技术,进行机场道面再生混凝土的强度、抗冻性、抗渗性和耐磨性等室内试验研究和现场应用.同时通过道面再生混凝土的微观结构分析,揭示其性能机理.研究结果表明:所配制的道面再生混凝土性能比普通道面混凝土的性能优,满足机场道面要求,抗折强度较普通道面混凝土提高4%~11%;抗冻等级高达F250,较普通道面混凝土提高200%以上,可以满足严寒地区道面混凝土抗冻要求;道面再生混凝土静水压力抗渗等级

  8. Evaluation and verification of two systems for mechanistic structural design of asphalt concrete pavements in Nebraska

    Science.gov (United States)

    Sneddon, R. V.

    1982-07-01

    The VESY-3-A mechanistic design system for asphalt pavements was field verified for three pavement sections at two test sites in Nebraska. PSI predictions from VESYS were in good agreement with field measurements for a 20 year old 3 layer pavement located near Elmwood, Nebraska. Field measured PSI values for an 8 in. full depth pavement also agreed with VESYS predictions for the study period. Rut depth estimates from the model were small and were in general agreement with field measurements. Cracking estimates were poor and tended to underestimate the time required to develop observable fatigue cracking in the field. Asphalt, base course and subgrade materials were tested in a 4.0 in. diameter modified triaxial cell. Test procedures used dynamic conditioning and rest periods to simulate service conditions.

  9. The Construction Technology of Asphalt Concrete Pavement Joints%浅议沥青混凝土路面接缝施工技术

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    Along with the pavement construction technology continues to improve, asphalt concrete pavement has become the current preferred highway bridge pavement. And the pave-ment joint is an important link in the construction of asphalt pavement, and its construction quality directly affects the app-earance and performance of pavement. This paper briefly desc-rybes and analyzes the joint construction technique in asphalt pavement construction.%  随着路面施工技术的不断提高,沥青混凝土路面已成为当前公路道桥工程路面的首选。而路面接缝是沥青路面施工中的重要环节,其施工质量的好坏直接影响着路面的外观及其工作性能。本文针对沥青路面施工中的接缝施工技术方法进行了简要阐述和分析。

  10. The Fatigue Damage of Cement Concrete Pavement and Its Countermeasures%水泥混凝土路面疲劳破坏及其对策研究

    Institute of Scientific and Technical Information of China (English)

    陈积光; 肖四喜; 戚成安

    2012-01-01

    水泥混凝土路面的破坏主要表现为疲劳破坏.研究表明,混凝土的强度和路面表面的平整度,对路面的疲劳寿命影响很大.建议采用混凝土的"双向拉伸强度"作为混凝土路面板的厚度设计验算标准,并在施工中尽量整平路面,提高路表的平整度指标.%the destruction of the cement concrete pavement mainly is fatigue damage.The research shows that the strength of cement concrete pavement and its roughness influence the fatigue life very much."Two-way tensile strength" is suggested as the standard of concrete pavement board’s thickness of checking and design,as far as possible to leveling the pavement in construction and improves the roughness index of the pavement.

  11. 浅谈高速沥青混凝土路面施工接缝处理%Discuss the Joint Treatment of Highway Asphalt Concrete Pavement Construction

    Institute of Scientific and Technical Information of China (English)

    樊琳琳

    2014-01-01

    针对高速沥青混凝土路面施工接缝处理,本文主要探讨了路面施工接缝处理和施工接缝碾压工艺等技术。为了提高高速沥青混凝土路面实施接缝处理技术,需要提出有效的合理的措施。%In view of the joint treatment of highway asphalt concrete pavement construction, this article mainly discusses the technologies of pavement construction joint treatment and construction joint compaction craft. In order to improve the i-mplementation of joint treatment technology in highway asph-alt concrete pavement, people need put forward effective and reasonable measures.

  12. Discussion on maintenance of asphalt concrete pavement in the rural highway%论农村公路沥青混凝土路面养护方法

    Institute of Scientific and Technical Information of China (English)

    邹海洋

    2013-01-01

    Asphalt concrete pavement with many excellent properties is widely used in road construction.But the asphalt concrete pavement in the use of the process will still exist all kinds of diseases,these diseases will have a very negative impact on the road quality and traffic safety.This paper expounds the importance of rural highway maintenance,then introduces the diseases and causes of asphalt concrete pavement,at last puts forward maintenance measures of asphalt concrete pavement of rural highway.%沥青混凝土路面具备很多优良的性能,在道路建设中应用非常广泛。但是沥青混凝土路面在使用过程中,还是会存在各种各样的病害,这些病害对公路质量水平和行车安全会产生十分不利的影响。文章阐述了农村公路养护的重要性,介绍了沥青混凝土路面的病害和成因,并提出了农村公路沥青混凝土路面养护措施。

  13. Strain distribution and crack detection in thin unbonded concrete pavement overlays with fully distributed fiber optic sensors

    Science.gov (United States)

    Bao, Yi; Chen, Genda

    2016-01-01

    This study aims at evaluating the feasibility of strain measurement and crack detection in thin unbonded concrete pavement overlays with pulse prepump Brillouin optical time domain analysis. Single-mode optical fibers with two-layer and three-layer coatings, respectively, were applied as fully distributed sensors, their performances were compared with analytical predictions. They were successfully protected from damage during concrete casting of three full-scale concrete panels when 5 to 10-cm-thick protective mortar covers had been set for 2 h. Experimental results from three-point loading tests of the panels indicated that the strain distributions measured from the two types of sensors were in good agreement, and cracks can be detected at sharp peaks of the measured strain distributions. The two-layer and three-layer coated fibers can be used to measure strains up to 2.33% and 2.42% with a corresponding sensitivity of 5.43×10-5 and 4.66×10-5 GHz/μɛ, respectively. Two cracks as close as 7 to 9 cm can be clearly detected. The measured strains in optical fiber were lower than the analytical prediction by 10% to 25%. Their difference likely resulted from strain transfer through various coatings, idealized point loading, varying optical fiber embedment, and concrete heterogeneity.

  14. Construction and Preliminary HVS Tests of Pre-Cast Concrete Pavement Slabs

    OpenAIRE

    Kohler, Erwin R.; du Plessis, Louw; Theyse, Hechter

    2008-01-01

    This report presents the details on the construction and preliminary load tests on an experimental pavement comprised of ten pre-cast slabs of the pavement known as the Super-Slab® System, installed at the intersection of I-15 and SR210, in San Bernardino County in southern California. The construction of the test section consisted of: (a) Construction of a cement-treated base (CTB), (b) Preparation of a sand bedding layer, (c) Placement of the pre-cast slabs, (d) Application of grout materi...

  15. Analysis on temperature field calculation of high permeable concrete pavement%高透水性混凝土路面温度场计算分析

    Institute of Scientific and Technical Information of China (English)

    王从锋; 刘德富

    2011-01-01

    针对高透水混凝土路面温度场分布特性,建立了高透水混凝土路面一维热传导模型,确定了计算边界条件和初始条件,并通过实测数据进行了验证,结果较为合理,为高透水混凝土路面温度计算分析提供了理论参考.%For temperature field distribution of high-pervious concrete pavement. This paper builds high-permeable concrete pavementone-dimensional heat conduction models and ascertains the calculation of boundary conditions and initial conditions, and are validatedby the actual results are more reasonable for the high permeable concrete pavement temperature calculation provides a theoreticalreference.

  16. Environmental performance and mechanical analysis of concrete containing recycled asphalt pavement (RAP) and waste precast concrete as aggregate.

    Science.gov (United States)

    Erdem, Savaş; Blankson, Marva Angela

    2014-01-15

    The overall objective of this research project was to investigate the feasibility of incorporating 100% recycled aggregates, either waste precast concrete or waste asphalt planning, as replacements for virgin aggregates in structural concrete and to determine the mechanical and environmental performance of concrete containing these aggregates. Four different types of concrete mixtures were designed with the same total water cement ratio (w/c=0.74) either by using natural aggregate as reference or by totally replacing the natural aggregate with recycled material. Ground granulated blast furnace slag (GGBS) was used as a mineral addition (35%) in all mixtures. The test results showed that it is possible to obtain satisfactory performance for strength characteristics of concrete containing recycled aggregates, if these aggregates are sourced from old precast concrete. However, from the perspective of the mechanical properties, the test results indicated that concrete with RAP aggregate cannot be used for structural applications. In terms of leaching, the results also showed that the environmental behaviour of the recycled aggregate concrete is similar to that of the natural aggregate concrete. PMID:24316812

  17. The Impact of Traffic-Induced Bridge Vibration on Rapid Repairing High-Performance Concrete for Bridge Deck Pavement Repairs

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2014-01-01

    Full Text Available Based on forced vibration tests for high-performance concrete (HPC, the influence of bridge vibration induced by traveling vehicle on compressive strength and durability of HPC has been studied. It is concluded that 1 d and 2 d compressive strength of HPC decreased significantly, and the maximum reduction rate is 9.1%, while 28 d compressive strength of HPC had a slight lower with a 3% maximal drop under the action of two simple harmonic vibrations with 2 Hz, 3 mm amplitude, and 4 Hz, 3 mm amplitude. Moreover, the vibration had a slight effect on the compressive strength of HPC when the simple harmonic vibration had 4 Hz and 1 mm amplitude; it is indicated that the amplitude exerts a more prominent influence on the earlier compressive strength with the comparison of the frequency. In addition, the impact of simple harmonic vibration on durability of HPC can be ignored; this shows the self-healing function of concrete resulting from later hydration reaction. Thus, the research achievements mentioned above can contribute to learning the laws by which bridge vibration affects the properties of concrete and provide technical support for the design and construction of the bridge deck pavement maintenance.

  18. 高性能混凝土路面应用研究%Application of high performance concrete pavement

    Institute of Scientific and Technical Information of China (English)

    马转

    2011-01-01

    The use of local materials,optimized mix design principles and steps are made to get the optimal mix,and pilot study of C35-F5.0 performance of cement concrete pavement is performed and good results are obtained in practical application.%利用地方材料,提出优化配合比设计原则和设计步骤,得到优化配合比,全面进行了C35-F5.0公路路面水小泥混凝土的性能试验研究,在实际工程进行试应用,取得良好效果。

  19. Crumb Rubber in cold recycled bituminous mixes

    DEFF Research Database (Denmark)

    Dondi, Giulio; Tataranni, Piergiorgio; Pettinari, Matteo;

    2014-01-01

    Today recycling is one of the most innovative and interesting techniques for the rehabilitation of destressed road pavements. In recent years the increased interest in this process, has led to the development of various alternative methods for the recovery and the reuse of road bituminous materials....... Cold recycling is, among the recycling techniques, certainly the most studied and developed: it allows the recovering of bituminous material from an existing pavement without the addition of heat, whilst ensuring the creation of high quality bound base layers. A wide range of materials have been tested...... together with Reclaimed Asphalt Pavement (RAP) and, consequently, there is a large number of variables that can be considered in the mix-design process of new eco-friendly Cold Recycled Mixes. In particular, the present research involves the use of Crumb Rubber within a mixture containing 100% Reclaimed...

  20. Advanced methodology for optimization of mixture design of asphalt concrete containing reclaimed asphalt pavement material

    OpenAIRE

    Bressi, Sara

    2016-01-01

    Despite the massive use of Reclaimed Asphalt Pavement (RAP) in Hot Mix Asphalt (HMA) production, the chemo-physical phenomena that characterise the fabrication of these mixtures have not yet been completely explored. The detection and understanding of these mechanisms as well as the study of the heterogeneity that characterizes high RAP mix production are fundamental to improving the approach to recycling, because they represent the source of the mixture characteristics and performance. This...

  1. Causes and Treatment of Slab Breakage on Cement Concrete Pavement%水泥混凝土道面断板原因及防治

    Institute of Scientific and Technical Information of China (English)

    朱维光; 王硕太; 岑国平

    2011-01-01

    For slab breakage on cement concrete pavement in China, based on introducing the diseases of broken slab, the causes of concrete pavement slab breaking are analyzed from material, design, construction and management and the corresponding control measure is advanced in this paper so as to reduce slab breakage rate on cement pavement and realize long life and low maintenance of cement pavement.%针对我国水泥混凝土路面的断板破坏现象,在介绍混凝土路面断板危害的基础上,从材料、设计、施工和管理等方面分析了混凝土路面断板的原因,并提出了相应的防控措施,以期降低混凝土路面的断板率,实现混凝土路面的"长寿命、低维护".

  2. G4高速公路湖南耒宜段大修工程路面结构方案设计%Pavement Structure Design of LeiYi Expressway Overhaul Engineering

    Institute of Scientific and Technical Information of China (English)

    吴超凡; 黄治湘; 张继森

    2014-01-01

    This paper introduces the original variety of Leiyi Expressway pavement structure,traf-fic flow and pavement damage.According to the pavement structure specific,traffic flow and axle load disparity of the road,using a technical and economical comparison,the original continuous reinforced concrete pavement overlay asphalt concrete pavement structure,the original ordinary cement concrete and reinforced concrete pavement overlay continuously reinforced concrete composite pavement,milling and overlay single or bunk asphalt pavement layer on the original asphalt pavement,the original asphalt pave-ment overlay situ thermal regeneration after single and double bituminous surface layer structure.%介绍了耒宜高速公路原路面的多种路面结构与交通流量及路面损害情况,针对具体的路面结构与左右幅交通流量与轴载的悬殊差异,经技术经济比较,采用了在原连续配筋混凝土路面上直接加铺沥青混凝土路面结构;在原普通水泥混凝土与钢筋混凝土路面上加铺连续配筋混凝土复合式路面;在原沥青路面上进行铣刨加铺单层沥青面层与双层沥青面层、对原沥青路面进行就地热再生后加铺单层与双层沥青面层结构。

  3. 超载作用下沥青混凝土路面的受力特性分析%Stress Analysis of Asphalt Concrete Pavement Under Overload

    Institute of Scientific and Technical Information of China (English)

    崔学民; 陈德华

    2012-01-01

    Based on the breakage of asphalt concrete pavement of Foshan-Kaiping Expressway, elastic layered theory is used to analyze the stress and deformation of the overloaded asphalt concrete pavement, the effects of overloaded vehicles on stress characteristics and fatigue lifetimes are discussed theoretically.%根据佛开高速公路沥青混凝土路面破损情况,应用弹性层状体系理论分析沥青混凝土路面在超载作用下的应力和变形,从理论上探讨超载车辆对路面的受力特性和疲劳寿命产生的影响.

  4. 机场水泥混凝土道面施工质量控制技术%Quality Control Technology for Airport Cement Concrete Pavement Construction

    Institute of Scientific and Technical Information of China (English)

    董军; 贡文献

    2011-01-01

    针对机场水泥混凝土道面施工中容易出现掉边掉角、表面网状或环状裂纹、板体断裂和蜂窝麻面等质量通病,根据大面积混凝土铺筑施工的特点和环境因素,综合分析其质量通病产生的原因,并提出相应的施工控制措施,在实践中取得了明显效果,可供水泥混凝土道面施工参考.%For the common quality defects on airport cement concrete pavement such as side or corner peeling,surface pattern crack or annular crack, slab fracture, and voids and pits, according to the characteristics of large area concrete pavement construction and environmental factors, the causes of these quality defects are analyzed and the corresponding control measures are put forward, which have achieved significant effect in practical engineering. These measures can be reference for cement concrete pavement construction.

  5. Cement concrete pavement summary of temperature field%普通水泥混凝土路面温度应力研究

    Institute of Scientific and Technical Information of China (English)

    曾惠珍; 吴梅容

    2011-01-01

    水泥混凝土路面直接暴露在大气之中,一年四季大气温度周期性的变化以及每一天白昼黑夜气温的变化.使得混凝土路面的温度也随之产生周期性的变化。本文论述了水泥混凝土路面温度应力诞生与发展的必然性.全面系统介绍了国内外温度应力计算公式的发展历程,提出了应进一步开展的研究工作。%Cement concrete pavements are normally directly exposed to the atmophere. The periodic changes of air temperature over years cause the periodic temperature changes of concrete pavements. The article introduces the ne- cessity of the creation and development of the temperature stress of cement concrete pavement ,and introduces the de- velopment process of the calculating formula for temperature stress at home and abroad comprehensively and systemat- ically.At last,we have an outlook for the further reseach.

  6. Laboratory Evaluation of Corrosion Resistance of Steel Dowels in Concrete Pavement

    OpenAIRE

    Mancio, Mauricio; Carlos, Cruz Jr.; Zhang, Jieying; Harvey, John T; Monteiro, Paulo J. M.; Ali, Abdikarim

    2005-01-01

    The objective of this study was to perform a laboratory investigation of the corrosion performance of several types of steel dowels embedded in concrete beams. The concrete beams and dowels were subjected to exposure to concentrated chloride solutions intended to accelerate corrosion and simulate environmental conditions. The purpose of this investigation was to develop recommendations for use of different types of dowels for different environmental risk conditions. To provide an indication o...

  7. On application of steel fiber concrete in bridge deck pavement%钢纤维混凝土在桥面铺装中的运用

    Institute of Scientific and Technical Information of China (English)

    白建珍

    2012-01-01

    简要介绍了钢纤维混凝土的一些技术特性和要求,从配合比设计、现场拌合、施工控制等方面入手阐述了钢纤维混凝土与普通混凝土的区别,以促进钢纤维混凝土在桥面铺装中的运用。%The paper briefly introduces the technical features and requirements of the steel fiber concrete, illustrates the differences between the steel fiber concrete and common concrete from the design of the mix proportion, the mixing on the spot, and the construction control, so as to enhance the application of the steel fiber concrete in the bridge deck pavement.

  8. Permeability predictions for sand-clogged Portland cement pervious concrete pavement systems.

    Science.gov (United States)

    Haselbach, Liv M; Valavala, Srinivas; Montes, Felipe

    2006-10-01

    Pervious concrete is an alternative paving surface that can be used to reduce the nonpoint source pollution effects of stormwater runoff from paved surfaces such as roadways and parking lots by allowing some of the rainfall to permeate into the ground below. This infiltration rate may be adversely affected by clogging of the system, particularly clogging or covering by sand in coastal areas. A theoretical relation was developed between the effective permeability of a sand-clogged pervious concrete block, the permeability of sand, and the porosity of the unclogged block. Permeabilities were then measured for Portland cement pervious concrete systems fully covered with extra fine sand in a flume using simulated rainfalls. The experimental results correlated well with the theoretical calculated permeability of the pervious concrete system for pervious concrete systems fully covered on the surface with sand. Two different slopes (2% and 10%) were used. Rainfall rates were simulated for the combination of direct rainfall (passive runoff) and for additional stormwater runoff from adjacent areas (active runoff). A typical pervious concrete block will allow water to pass through at flow rates greater than 0.2 cm/s and a typical extra fine sand will have a permeability of approximately 0.02 cm/s. The limit of the system with complete sand coverage resulted in an effective system permeability of approximately 0.004 cm/s which is similar to the rainfall intensity of a 30 min duration, 100-year frequency event in the southeastern United States. The results obtained are important in designing and evaluating pervious concrete as a paving surface within watershed management systems for controlling the quantity of runoff. PMID:16563606

  9. Pervious Pavement System Evaluation-Poster

    Science.gov (United States)

    Pervious pavement is a low impact development stormwater control. The Environmental Protection Agency's Urban Watershed Management Branch is evaluating interlocking concrete pavingstone pervious pavement systems. The pavingstones themselves are impermeable, but the spaces between...

  10. 影响水泥混凝土路面平整度的因素分析与对策%Analysis on the Factors Influencing Cement Concrete Pavement Flatness and Countermeasures

    Institute of Scientific and Technical Information of China (English)

    王晓玲

    2011-01-01

    本文对高速公路水泥混凝土路面平整度的影响因素进行了分析,详细地阐述了提高混凝土路面平整度的施工控制措施,以保证水泥混凝土路面平整、行车舒适、经久耐用,对水泥混凝土路面发展具有重要意义.%The paper analyzes the factors affecting highway cement concrete pavement flatness and describes control measures in detail to improve the construction of concrete pavement smoothness so that to ensurethe cement concrete road surface flatness, driving comfort and durability, which is of great significance to the development of cement concrete pavement.

  11. Multifractal Characteristics of Asphalt Concrete Pavement Macrotexture%沥青混凝土路面宏观纹理的多重分形特征

    Institute of Scientific and Technical Information of China (English)

    苗英豪; 宋萍萍

    2013-01-01

    为深入分析沥青混凝土路面表面宏观纹理特征,在12条不同等级的道路上,选取了包含沥青混凝土(AC)、沥青玛蹄脂碎石(SMA)、开级配抗滑磨耗层(OGFC)、微表处(MS)和稀浆封层(SS)等路面类型的35个测试点,利用激光断面仪开展了路面表面宏观纹理断面的现场测试.分析表明,沥青混凝土路面表面宏观纹理断面具有典型的多重分形特征,多重分形谱呈向右的钩形,多重分形谱的分布宽度(△a)反映了路面断面起伏幅度的变化范围,与路面表面平均断面深度(MPD)之间有较为显著的相关性.最小概率子集与最大概率子集的分形维数差(△f(a))表征了路面表面纹理不同起伏幅度的分布情况,从一个新的角度描述了路面表面断面的特征,丰富了对路面表面宏观纹理特征的描述.%To deeply understand the features of asphalt concrete pavement macrotexture, field tests are conducted using laser profile tester at 35 test sites in 12 sections with 5 pavement types including Asphalt Concrete (AC), Stone Matrix Asphalt (SMA), Open Graded Friction Course (OGFC), Micro-Surfacing (MS) , and Slurry Seal (SS). It is shown that profile of asphalt concrete pavement macrotexture has significant multifractal property. All multifractal spectrums are like a hook facing right. The width of multifractal spectrum (△a) indicates the variation range of profile amplitude, which has significant correlation-ship with the Mean Profile Depth (MPD). Fractal dimension difference between the subset with minimum probability and the subset with maximum probability (△f(a)) describes the distribution of profile amplitude which characterizes the pavement macrotexture from another view and is a new choice for asphalt concrete pavement macrotexture charecterization.

  12. Study on construction technology of steel fiber concrete pavement%钢纤维混凝土路面施工技术研究

    Institute of Scientific and Technical Information of China (English)

    李二虎

    2012-01-01

    With an introduction on the construction technology of steel fiber concrete pavement, combining with the norms and standards, the pa- per introduces the steel fiber concrete mixing design, and describes the construction quality control and structural design, with a view to guide practice and to promote the application of steel fiber concrete technology in highway bridge engineering.%对钢纤维混凝土路面施工技术进行了探讨,结合规范标准,介绍了钢纤维混凝土的配比设计,并对其施工质量控制和构造设计作了具体阐述,以指导实践,促进钢纤维混凝土技术在道路桥梁工程中的应用。

  13. 钢混结合段桥面铺装方案研究%Study of Deck Pavement Scheme for Steel-Concrete Joint Section

    Institute of Scientific and Technical Information of China (English)

    唐颂; 赵国云; 谢远新; 陈仕周

    2015-01-01

    为了解钢混结合段铺装结构的受力特征 ,设计出科学合理的铺装结构 ,以永川长江大桥——(64+2 × 68+608+2 × 68+64 ) m七跨连续半飘浮体系双塔混合梁斜拉桥为例 ,采用理论计算与试验研究相结合的方法 ,对钢混结合段采用环氧沥青混凝土、浇注式沥青混凝土铺装方案的结构受力特性进行分析 ,结合2种方案的优点 ,研究出灌注式环氧树脂混凝土铺装结构.分析结果表明 :相对于钢箱梁段 ,钢混结合段铺装对铺装混凝土的耐疲劳性能要求不高 ,但对防水粘结层的粘结和抗剪性能有较高要求.灌注式环氧树脂混凝土铺装结构是将环氧树脂灌入已经铺装好的沥青混合料中 ,具有较高的力学强度和耐疲劳性能.实桥使用效果证实了该铺装结构设计合理、工艺可行.%In order to examine the load bearing behavior of the pavement structure of the steel-concrete joint section and work out rational pavement structure ,the Yongchuan Changjiang River Bridge ,a seven-span two-pylon hybrid girder cable-stayed bridge of half-floating system and with span arrangement of (64+2 × 68+608+2 × 68+64) m ,was cited as an example.By the combined application of theoretical calculation and experimental study , the load bearing behavior of the bridge structures respectively with epoxy asphalt concrete and cast asphalt concrete was analyzed. Upon the advantages of the two schemes ,the injected epoxy resin concrete pavement was pro-posed.The results of the analysis indicate that the pavement of the steel-concrete joint section is not critical about the fatigue resistant performance of concrete when compared with the steel box girder section ,but requires that the w ater-proof layer have sound cohesion and anti-shearing capac-ity.T he injected epoxy resin concrete pavement is formed by injecting epoxy resin into the asphalt-aggregate mixture already paved ,with high mechanical strength and sound fatigue

  14. Fatigue life predictions of concrete pavement with premature cracking%混凝土路面板早期开裂疲劳寿命预测

    Institute of Scientific and Technical Information of China (English)

    魏亚

    2014-01-01

    为准确预测水泥混凝土路面板在早期裂缝情况下的疲劳寿命,帮助制定合理的维修计划、延长道路使用寿命,该文通过小梁四点弯拉及混凝土板疲劳加载试验,研究了混凝土断裂力学参数及疲劳行为,并对有裂缝混凝土板的疲劳寿命进行预测分析.试验研究和模型预测均表明:混凝土路面板早期开裂疲劳寿命或破损过程分为3个阶段,且板的疲劳断裂寿命远小于传统模型预测值;开放交通时间的早晚对板的疲劳寿命有至关重要影响.研究结果对于准确预测疲劳寿命和及时进行路面维修与裂缝处理具有实际意义.%Premature transverse cracking can occur in concrete pavement subject to repetitive truck loading.This premature cracking may cause final failure of the pavement and greatly reduce the service life.This study investigates the fracture properties of notched concrete beams to establish a fatigue life prediction model.Both the model and the experimental tests show that the pavement fatigue life is greatly reduced compared to traditional models if a partial depth crack develops within the first few days after placement.Thus,the opening time to traffic is crucial for the pavement fatigue life.The findings are of significance for proper schedule maintenance plans.

  15. Plastic Shrinkage Cracking Behavior of Pavement Cement Concrete at Early Age%路面水泥混凝土的早期塑性开裂性能

    Institute of Scientific and Technical Information of China (English)

    王稷良; 田波; 张擎

    2012-01-01

    针对目前路面水泥混凝土易于出现塑性开裂的情况,为更合理优化路面混凝土原材料与配合比设计参数,采用笠井芳夫教授提出的大板法,对比研究了水泥细度、矿物掺和料种类及掺量、混凝土配合比设计参数对路面混凝土早期塑性开裂性能的影响.试验结果表明,水泥的比表面积越大,矿物掺和料掺量越高,水灰比越小,混凝土浆集比越大时,越不利于路面水泥混凝土的塑性开裂控制.且相对于粉煤灰与矿粉,硅灰作为矿物掺和料时,硅灰将更显著降低混凝土抗塑性开裂等级.为提高路面水泥混凝土的抗裂性,宜选择比表面积小于360 kg/m3的水泥,水灰比大于0.4、浆集比小于275:725的配合比设计参数.当混凝土中掺加活性矿物掺和料时,应加强混凝土的早期养护,以抑制塑性裂缝的出现.%To cope with the situation that present pavement cement concrete is easy to appear plastic shrinkage cracking, in order to optimize the raw materials and the mix design parameters of pavement concrete more reasonably, the influence of fineness of cement, species and mixing amount of mineral admixture and concrete mix design parameters on early plastic shrinkage cracking performance of pavement cement concrete was comparatively studied by using the plate method proposed by Professor Kasai. The test results show that (1) it would be more detrimental to the control of plastic shrinkage cracking of pavement cement concrete when the cement specific surface area was larger, the content of mineral admixture became higher, the water-cement ratio turned smaller, and the cement paste-aggregate ratio trended to be greater; (2) relative to fly ash and mineral powder, silica fume will reduce the level of plastic shrinkage cracking resistance of concrete more significantly when used as mineral admixture; (3 ) in order to improve the crack resistance of pavement cement concrete, the mix design parameters should be

  16. 农村公路路面碾压混凝土性能(阶段性)研究%Rural highway pavement performance of roller compacted concrete(periodic) research

    Institute of Scientific and Technical Information of China (English)

    刘大超; 伏志明; 刘祥; 刘鹏; 江思颖

    2014-01-01

    Roller compacted concrete road pavement more routine normal concrete with compressive,flexural,impact resistance,fatigue resistance and so on significant performance advantages.It relied on Cangxi county ,Sichuan province rural highway pavement roller com-pacted concrete scientific research project,research on the basic performance of the pavement roller compacted concrete,analyzing factors that affect rural highway pavement roller compacted concrete workability,raw material control,and on this basis put forward rural high-way pavement roller compacted concrete mixing proportion range,on this basis,the research on the dosage of fly ash pavement influence of physical and mechanical properties of roller compacted concrete.%公路路面碾压混凝土较常规普通混凝土具有抗压、抗折、抗冲击、抗疲劳等性能的优点。依托四川省苍溪县农村公路路面碾压混凝土科研项目,对路面碾压混凝土的基本性能进行研究,分析影响农村公路路面的碾压混凝土工作性的因素,原材料控制以及在此基础上提出了农村公路路面碾压混凝土的配合比例范围,同时,研究粉煤灰掺量对路面碾压混凝土的物理力学及耐久性能的影响。

  17. Application Study on Geotextile as Bond-Breaking Layer Between Concrete Pavement Slab and Lean Concrete Base%土工布作水泥混凝土路面隔离层应用研究

    Institute of Scientific and Technical Information of China (English)

    林天干; 姚佳良; 于远征; 袁剑波

    2012-01-01

    主要结合广东、湖南等省高速公路中采用土工布作水泥混凝土路面隔离层进行的路面层间力学性能试验与工程应用研究,探讨了贫混凝土基层上铺筑水泥混凝土面层时采用土工布隔离层与无隔离层时的层间力学性能差别.通过现场试验路施工,总结了土工布用于路面隔离层的施工控制技术.获得的土工布隔离层层间力学性能参数与施工应用技术,为实体工程路面设计、施工控制提供了科学依据.%This research explored the difference in mechanical performance of slab-base interface between the pavements without a bond-breaking layer and the pavements with geotextile as the bond-breaking layer installed between the concrete pavement surface slab and the lean concrete base, via the field tests for mechanical performance of slab-base interface treated with geotextile as the bond-breaking layers in some highway projects of Hunan and Guangdong Provinces. The techniques of construction control in placing geotextile atop the lean concrete base as the bond-breaking layer is concluded from the construction of the field test roads. The mechanical performance of slab-base interface with geotextile as the bond-brea king medium derived from this research and the techniques of construction offer scientific reference to pavement design and construction control in the practical road engineering projects.

  18. Investigation of Anti-Icing Chemicals and Their Interactions with Pavement Concretes

    OpenAIRE

    Olek, Jan; Janusz, Anna; Jain, Jitendra; Ashraf, Warda

    2013-01-01

    The interactions of concrete specimens (both plain and with fly ash addition) with six different deicers was investigated by exposing them to solutions of sodium chloride (NaCl), magnesium chloride (MgCl2), calcium chloride (CaCl2), and the combinations of: sodium chloride with magnesium chloride (NaCl + MgCl2), sodium chloride with calcium chloride (NaCl + CaCl2), sodium chloride with agricultural by product – Ice Ban® (NaCl + Ice Ban®). In addition, control group of specimens was exposed to...

  19. 环氧沥青混凝土复合铺装结构疲劳试验研究%Research on the Fatigue Property of Multilayered Pavement on Concrete Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    陈团结; 钱振东

    2012-01-01

    水泥混凝土桥面铺装整体结构的疲劳特性是决定铺装层使用寿命的关键.通过对双层沥青铺装层结构的复合梁以及“水泥混凝土板十双层沥青混合料铺装”三层复合结构的疲劳试验,对水泥混凝土桥面铺装层复合结构的疲劳性能进行了研究,同时考虑了层间防水粘结层的影响.结果表明当微应变为700×10-6时,“环氧沥青混凝土+SMA”结构的疲劳寿命是其他类型铺装结构的1.4倍;“水泥混凝土板十环氧沥青混凝土+SMA”三层复合结构的疲劳寿命是其他类型铺装结构的2.1倍.结论表明“环氧沥青+SMA”复合铺装结构适宜于水泥混凝土桥面铺装.%It is key for life-span of deck pavement that if the fatigue property of the whole deck pavement structure is better or not. The facts showed that when some materials with good fatigue properties were adopted, but the life of deck pavement was not prolonged at all. Here some experiments on double-layered asphalt deck pavement and "concrete deck + double-layered asphalt deck pavement" were done, along with some researches on the fatigue property of multi-layered deck pavement, considering the influence of adhesion layer. Some conclusions have been arrived that when the micro strain equals to 700 × 10-6, the fatigue life of the beam combined with epoxy asphalt concrete and SMA is 1. 4 times than other deck pavement structures; the fatigue life of the triple-layered deck pavement combined with concrete deck, epoxy asphalt concrete and SMA is 2. 1 times than other type of deck pavement. That indicates that deck pavement combined with epoxy asphalt concrete and SMA is suitable for concrete bridges.

  20. Infiltration and Evaporation of Diesel and Gasoline Droplets Spilled onto Concrete Pavement

    Science.gov (United States)

    Hilpert, M.; Adria-Mora, B.

    2015-12-01

    Pollution at gas stations due to small spills that occur during refueling of customer vehicles has received little attention. We have performed laboratory experiments in order to assess the processes of evaporation and infiltration of fuel spilled onto concrete samples. Changes in mass of both spilled diesel and gasoline droplets as a function of time have been analyzed. The infiltrated mass is affected by variations in humidity, among other parameters, which influence the amount of water condensed onto the concrete. Therefore, we used a humidity data logger and statistical tools to predict the evolution of the real mass of infiltrated fuel. The infiltrated mass roughly decreases exponentially, but the difference in behavior between both fuel types is important. The percentage of evaporated mass is much larger for gasoline, while infiltration is more significant for diesel. Also, the percentage of infiltrated liquid depends on the initial droplet mass. We also developed a multiphysics model, which couples pore-scale infiltration to turbulent atmospheric transport, to explain the experimental data. In conclusion, a substantial amount of fuel could both seep into the ground to contaminate groundwater and be released to the atmosphere. More studies are needed to quantify the public health implications of the released pollutants.

  1. 活性粉末混凝土路面砖的经济性分析%The Economic Analysis of Reactive Powder Concrete Pavement Brick

    Institute of Scientific and Technical Information of China (English)

    杨丹; 王亚洲

    2015-01-01

    This paper mainly introduces the features and advantages of reactive powder concrete (RPC) pavement brick, and in the material composition of reactive powder concrete as the economy of the urban road brick are analyzed. Using of the reactive powder concrete pavement brick in Municipal Engineering can significantly increase the road service performance and durability, and play an important role in the future development of the road.%本文主要介绍了活性粉末混凝土(RPC)路面砖的特点和优势,并从材料组成上对活性粉末混凝土用作城市路面砖的经济性进行了分析。市政工程中采用活性粉末混凝土做路面砖,可以显著提高道路使用性能及耐久性,在未来道路发展中占有重要作用。

  2. Frost-resistant performance and mechanism of recycled concrete for airport pavement%机场道面再生混凝土的抗冻性能及机理

    Institute of Scientific and Technical Information of China (English)

    刘庆涛; 岑国平; 蔡良才; 吴和胜

    2011-01-01

    In order to study the frost-resistant performance and mechanism of the airport pavement recycled concrete,the "double mixing" technique with high quality fly ash and high efficiency admixture was adopted,then the mix proportion design of pavement recycled concrete was optimized and the frost-resistant performance was studied.Based on the testing results and the destroy phenomenons of the specimens,the frost-resistance performance evaluating indicators of the recycled concrete was discussed,and the frost-resistant mechanism of recycled concrete for airport pavement was analyzed in aspects of the air capacity,the micro-pore structure,the microstructure.It is suggested that the air capacity of the recycled concrete for pavement in the chilly area is 5%~6%,and high quality mineral admixtures should be added to the recycled concrete for pavement to improve the frost-resistance performance of the recycled concrete.The testing results show the frost-resistance grade of the recycled concrete for airport pavement is up to F250,the frost-resistance performance is superior to ordinary pavement concrete,which can meet the requirement of the pavement design specifications.%为了研究机场道面再生混凝土的抗冻性能及其机理,采用掺加优质粉煤灰和高效外加剂的"双掺"技术路线,进行机场道面再生混凝土配合比设计和抗冻性能研究.根据机场道面再生混凝土抗冻试验结果和试件破坏现象,探讨了再生混凝土抗冻性能评价指标.从含气量、孔结构和微观结构等方面,对机场道面再生混凝土的抗冻机理进行了分析,建议寒冷地区道面再生混凝土含气量为5%~6%,在再生混凝土中掺入优质矿物外掺料,提高机场道面再生混凝土的抗冻性能.结果表明:所配制的机场道面再生混凝土抗冻等级高达F250,抗冻性能优于普通道面混凝土,满足道面设计规范要求.

  3. Mechanical and Permeability Characteristics of Latex-Modified Pre-Packed Pavement Repair Concrete as a Function of the Rapid-Set Binder Content

    Directory of Open Access Journals (Sweden)

    Jae-Woong Han

    2015-10-01

    Full Text Available We evaluated the strength and durability characteristics of latex-polymer-modified, pre-packed pavement repair concrete (LMPPRC with a rapid-set binder. The rapid-set binder was a mixture of rapid-set cement and silica sand, where the fluidity was controlled using a latex polymer. The resulting mix exhibited a compressive strength of ¥21 MPa and a flexural strength of ¥3.5 MPa after 4 h of curing (i.e., the traffic opening term for emergency repairs of pavement. The ratio of latex polymer to rapid-set binder material was varied through 0.40, 0.33, 0.29, and 0.25. Mechanical characterization revealed that the mechanical performance, permeability, and impact resistance increased as the ratio of latex polymer to rapid-set binder decreased. The mixture exhibited a compressive strength of ¥21 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ¤0.29. The mixture exhibited a flexural strength of ¥3.5 MPa after 4 h when the ratio of latex polymer to rapid-set binder material was ¤0.33. The permeability resistance to chloride ions satisfied 2000 C after 7 days of curing for all ratios. The ratio of latex polymer to rapid-set binder material that satisfied all conditions for emergency pavement repair was ¤0.29.

  4. Experimental study on bending fatigue properties of basalt fiber reinforced concrete for airport pavement%玄武岩纤维机场道面混凝土弯曲疲劳性能试验研究

    Institute of Scientific and Technical Information of China (English)

    吴永根; 李文蕾; 黄命辉; 刁军亮

    2012-01-01

    通过弯曲疲劳试验,对比分析研究了玄武岩纤维道面混凝土和普通道面混凝土的弯曲疲劳性能,并得出疲劳方程.试验结果表明:掺入玄武岩纤维后能明显提高普通道面混凝土的抗弯曲疲劳性能,玄武岩纤维道面混凝土的疲劳寿命是普通道面混凝土的2.15 ~5.95倍,且疲劳寿命均服从两参数威布尔分布.本文的试验研究结果为玄武岩纤维在机场道面混凝土中的实际应用提供了依据.%Analyze and compare with the bending fatigue properties of basalt fiber reinforced concrete for airport pavement and plain pavement concrete by bending fatigue testing in laboratory, and obtains the fatigue equation. Test results indicate that the anti-fatigue property of pavement concrete can be unproved evidently by the basalt fiber being mixed into, fatigue life of basalt fiber reinforced pavement concrete is 2.15 - 5.95 times of those of plain pavement concrete, both fatigue life can be described by two parameters WeiBull distribution. Hie study results in the paper provide the experimental basis for the application of basalt fiber in airport pavement engineering construction practice.

  5. 混凝土养护剂在水泥路面中的应用研究%Application of Concrete Curing Compound in Cement Pavement

    Institute of Scientific and Technical Information of China (English)

    彭会明; 曾永革

    2011-01-01

    研究了自然条件下采用混凝土养护剂对水泥路面进行养护的影响因素及效果.对三条水泥混凝土路面公路的试验路段分别采取覆盖洒水养护、混凝土养护剂养护,其中混凝土养护剂的用量分别按200,300,350g/m2控制,将各种养护条件下28天的混凝土钻芯取样强度、回弹强度与相应标准养护条件下的强度进行对比,得出了养护剂的用量和养护温度对混凝土强度的影响以及使用养护剂可获更高的混凝土表面硬度的结论.%The influencing factors and effect of cement pavement maintenance using concrete curing compound under natural condition are studied in this paper. The test section of three cement concrete pavements are separately maintained by sprinkling and using concrete curing compound, the amount of which is controlled according to 200, 300, 350 g/m2. The core strength and rebound strength under each curing condition for 28 d are compared with that under the corresponding standard curing condition. The influence of the amount of curing compound and curing temperature on concrete strength are obtained. It is concluded that using curing compound can achieve higher surface hardness.

  6. Theoretical Development and Engineering Practice of Pavements in China

    Institute of Scientific and Technical Information of China (English)

    QIU Yan-jun

    2008-01-01

    This paper presents a comprehensive review of historical theory development and current construction practice of pavement engineering in China. Mechanical models, design guides, construction techniques, evaluation methods and maintenance standards are elaborated for Portland cement concrete (PCC) pavements and asphalt concrete (AC) pavements. Differences in design methodology among pavements of rural highways, urban roads and airport fields are discussed based on service requirements.Lessons and experiences based on the past 20 years' construction practice and pavement performance are summarized. Current research areas in pavement engineering associated with unconventional geological and/or landscaping in China's highway construction and national strategic plan for pavement engineering are also covered.

  7. 旧水泥混凝土路面碎石化后力学性能分析%Analysis for Mechanical Properties of Old Cement Concrete Pavement after Rubblization

    Institute of Scientific and Technical Information of China (English)

    熊斌丹; 林钦国; 吕勇衡

    2014-01-01

    This paper analyzes mechanism of strength formation on upper and lower resonance breaking layers on old cement pavement, performs deflection test and modulus resilience test for old cement pavement course and its breaking layers and analyzes mechanical properties of the breaking layers on old cement concrete pavement according to test results. The results show that the integral strength of old cement concrete pavement is good, but big difference exists, not favorable for direct strengthening and overlay of new structure layer; the integral strength of old cement concrete pavement after resonance breaking increases, but the homogeneity is very good and flexible feature is exhibited, more favorable for reinforcement and overlay of pavement so as to improve the service quality of pavement effectively.%对旧水泥路面共振破碎层分上层及下层进行强度形成机理分析,对破碎层旧水泥路面层及其破碎层进行弯沉测试和回弹模量测试,并根据测试结果对旧水泥混凝土路面破碎层的力学性能进行分析。结果表明:旧水泥混凝土路面整体强度虽然较好,但差异性很大,不利于直接补强和加铺新的结构层;共振破碎后的旧水泥混凝土路面整体强度下降,但均匀性很好,呈现出柔性特征,更有利于路面的补强和加铺,从而可有效提高路面的使用品质。

  8. Comparative analysis on concrete pavement stress under static and dynamic load%动静荷载作用下混凝土路面应力对比分析

    Institute of Scientific and Technical Information of China (English)

    于孙相

    2012-01-01

    对混凝土路面板在动态荷载及静态荷载两种荷载作用下的应力进行计算对比分析,得出行车静荷载作用下路面板疲劳寿命比行车动荷载作用下疲劳寿命大的结论,为混凝土路面板的疲劳寿命设计提供了一定的参考依据。%The paper calculates and comparatively analyzes the concrete pavement board stress under dynamic and static load, and finds out that the pavement board fatigue life under static load is longer than that under dynamic load, which has provided certain guidance for design the fatigue life of concrete pavement board in future.

  9. 谈农村公路水泥混凝土路面的施工质量控制%Talking about the construction quality control of rural highway cement concrete pavement

    Institute of Scientific and Technical Information of China (English)

    周明伟

    2012-01-01

    Integrating with the characteristics of cement concrete pavement, the paper explores the construction quality control measures of rural highway cement concrete pavement, and points out some construction points including subgrade, pavement materials, construction procedure and construction technology and so on, with a view to guide practice.%结合水泥混凝土路面特点,探讨了农村公路水泥混凝土路面的施工质量控制措施,指出应从路基、路面材料、施工工序及施工工艺等方面入手,注重细节,以期指导实践。

  10. Pervious Pavement System Evaluation- Abstract

    Science.gov (United States)

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  11. 机场道面再生混凝土研究应用现状与发展%Research and Application Status and Development of Recycled Concrete on Airport Pavement

    Institute of Scientific and Technical Information of China (English)

    刘庆涛; 岑国平; 王硕太

    2011-01-01

    在对国内外再生混凝土研究应用现状进行分析的基础上,提出了在机场道面工程中应用再生混凝土的可行性.针对再生骨料的特点,提出了配制机场道面再生混凝土的技术路线、机理与研究方向,为在机场道面工程中研究、配制并铺筑高性能再生混凝土道面提供参考.%Based on the research and application of recycled concrete at home and abroad, the feasibility of recycled concrete in airport pavement engineering is put forward in this paper. According to the characteristics of recycled aggregates, the technical route, mechanism and research direction of recycled concrete on airport pavement are advanced to provide reference for research, preparation and construction of high-performance recycled concrete pavement in airport pavement engineering.

  12. Permeable Pavement Research - Edison, New Jersey

    Science.gov (United States)

    This presentation provides the background and summary of results collected at the permeable pavement parking lot monitored at the EPA facility in Edison, NJ. This parking lot is surfaced with permeable interlocking concrete pavers (PICP), pervious concrete, and porous asphalt. ...

  13. Structural Design and Mechanical Analysis of Full-Depth High Modulus Asphalt Concrete Pavement%全厚式高模量沥青混凝土路面结构设计及力学分析

    Institute of Scientific and Technical Information of China (English)

    李涛; 刘宁; 张涛

    2013-01-01

    The pavement special program PADS is used to calculate the three kinds of asphalt concrete pavement structure thickness which are full-depth high modulus, full-depth ordinary and semi-rigid base asphalt concrete pavement, respectively. The 3-D element model of asphalt concrete pavement structure is built based on the elastic mechanics to evaluate the design bottom stress state under loads. The rutting of the three kinds of pavement is determined by using asphalt concrete pavement permanent deformation prediction method in MEPDG of the United States. Also, their fatigue life is calculated. The results show that the full-depth high modulus asphalt concrete pavement structure is able to effectively decrease the thickness of the pavement structure, at the same time exhibits the best overall performance in rutting resistance and fatigue properties.%利用路面专用程序PADS计算全厚式高模量、全厚式普通和半刚性基层3种沥青混凝土路面结构厚度;根据弹性层状理论体系,建立了上述3种沥青混凝土路面结构三维有限元模型,对路面结构在荷载作用下的设计层层底应力状态进行对比分析;应用美国MEPDG推荐的沥青混凝土路面永久变形预估方法对沥青混凝土路面结构进行车辙预估,并对其疲劳寿命进行了计算.结果表明,全厚式高模量沥青混凝土路面结构能够有效减薄路面结构厚度,是抗车辙性能及疲劳性能综合最优的路面结构类型.

  14. 水泥混凝土路面填缝料疲劳试验方法研究%Research on Fatigue Test Methods for Joint Sealing Materials for Cement Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    王宝松; 王进勇; 龙丽琴

    2012-01-01

    水泥混凝土路面填缝料在实际应用中,受气候、机械外力作用产生疲劳老化,使用寿命下降.填缝料疲劳导致地表水渗入基层是水泥混凝土路面破坏的重要原因之一.现有填缝料评价体系中无体现疲劳性能的评价指标.基于对现有水泥混凝土路面接缝料的力学研究和室内试验,提出适合于水泥混凝土路面填缝料疲劳性能检测的试验方法和仪器,其对于水泥混凝土路面填缝料的研究及应用具有重要意义.%Joint sealing materials for cement concrete pavement in practical application produce fatigue aging under effect of climate and mechanical force and the service life decreases. Penetration of surface water into base course caused by fatigue of joint sealing materials is one of important reasons for damage to cement concrete pavement. Existing evaluation system for joint sealing materials has no evaluation indices for fatigue performance. On the basis of mechanical research and indoor test for joint sealing materials for cement concrete pavement, this paper proposes test methods and instruments suitable for detection of fatigue performance of joint sealing materials for cement concrete pavement, which show importance significance for research and application of joint sealing materials for cement concrete pavement.

  15. 机场水泥混凝土道面新型接缝施工工艺研究%Research on Construction Technology of New Type Joint of Concrete Pavement in Airport Cement Concrete

    Institute of Scientific and Technical Information of China (English)

    李建举; 张鲁渝

    2015-01-01

    机场刚性道面是由多块板通过各种接缝连接起来的一个整体,道面缝长约是道面长度的20倍.然而,接缝是水泥混凝土道面最薄弱的部位,因此接缝在整个机场场道工程施工中不容轻视,其施工质量直接影响着机场道面的使用性能、整体强度和使用寿命.通过采用新型接缝形式,改变传统的水泥混凝土道面接缝和扩缝工艺——将宽缝变窄,然后对窄缝进行倒角.这种接缝形式不但能够提高水泥混凝土道面的接缝质量,保护水泥混凝土道面最薄弱的地方——接缝边角,还能增强灌缝材料的黏聚力,减少飞机滑行时的颠簸,增加飞机起飞、着陆时人员的舒适度.该接缝倒角技术对机场场道工程建设具有重要的革新意义,不仅可以降低道面被破坏的概率,减少道面运行后的维修费用,还可以从源头上降低因道面破损而导致飞机发动机吸入破碎物的概率,提高了道面使用的安全性和可靠性,具有明显的经济效益和社会效益.%The rigid pavement of the airport is a whole, which is connected by a variety of joints, and the length of the road is about 20 times the length of the pavement. However, joint is the weakest of the cement concrete road surface parts, so juncture in the airport runway construction can't be ignored; its construction quality directly affects the use of airport pavement performance, the overall strength and service life. By using the new joint form, change the traditional cement concrete road surface joint and expansion of the sewing process -- the wide gap narrowed, and then in the narrow chamfering. This kind of joint form not only can improve the joint quality of cement concrete pavement, protect the weakest place of cement concrete pavement-- joint edge angle, but also enhance the cohesion of the filling material, reduce the turbulence of the aircraft, and increase the comfort of the aircraft during takeoff and landing. The joint

  16. 不同纹理水泥混凝土路面降噪与抗滑特性%Skid-resistance and Denoising Properties of Cement Concrete Pavement with Different Surface Texture

    Institute of Scientific and Technical Information of China (English)

    刘英; 田波; 牛开民

    2012-01-01

    采用新型隔离风噪的路面-轮胎噪声测试方法和横向摩擦力系数测定车对不同纹理构造的路面进行噪声和抗滑性能测试,分析了不同纹理构造路面的抗滑降噪机理.结果证明通过对噪声测试设备的改进,可以有效的排除外界噪声的干扰,保证噪声试验数据的准确性.此外,通过改善水泥混凝土路面常用纹理,可以达到降低路面噪声且提高路面抗滑能力的目的.多孔水泥混凝土路面、露石水泥混凝土路面和纵向刻槽路面噪声值与沥青路面相当,并且具有良好的抗滑性能.%By using an improved road/tyre noise test method with windscreen and lateral skid-resistance test vehicle, we tested the noise and skid-resistance property of different pavement surface texture, and also analysed the skid-resistance and denoising mechanism of different surface texture. It proved that (1) we can effectively exclude the interference of outside noise, and ensure the accuracy of noise test data by improving noise test equipment; (2 ) we can reduce road/tyre noise of cement concrete pavement and increase skid-resistance property by improving conventional surface texture; ( 3 ) the noise values of porous cement concrete pavement, exposed aggregate cement concrete pavement and longitudinal grooved pavement are equivalent to that of asphalt pavement, and they has good skid-resistance property.

  17. 地聚合物混凝土及其在水泥混凝土路面快速修补中的应用%Preparation of Geopolymeric Concrete and Its Application to Rapid Repair of Cement Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    彭小芹; 杨涛; 王开宇; 孟祥杰

    2011-01-01

    To solve the problems of long traffic opening time and low durability of the existing cement concrete pavement repair materials, a geopolymeric concrete was developed and applied to rapid repair of cement concrete pavement. The influence of Portland cement dosage and activator to solid ratio on the early strength of geopolymer was studied experimentally, and the mechanical properties, adhesive strength, shrinkage of the geopolymeric concrete were investigated as well. The results show that the geopolymer has the highest early strength when the dosage of cement is 10% , and the activator to solid ratio is 0.75. The 8-hour flexural strength and compressive strength of the geopolymer concrete prepared are 3.25 and 43.6 MPa, respectively, and the 8-hour mechanical properties, adhesive strength, and shrinkage of the geopolymeric concrete meet the technical requirements of repair concrete.%为解决水泥混凝土路面修补材料存在的路面开放交通时间偏长和耐久性较差的问题,研制了地聚合物混凝土,并将其应用于水泥混凝土路面的快速修补.实验研究了普通硅酸盐水泥掺量和激固比对地聚合物早期强度的影响、地聚合物混凝土的力学性能、粘结强度和收缩率.结果表明:水泥掺量为10%、激固比为0.75时,地聚合物早期力学性能最好,地聚合物混凝土8 h时的抗折强度和抗压强度分别为3.25和43.6 MPa,其力学强度、粘结强度、收缩率均满足路面修补混凝土的技术要求.

  18. Permeable Pavements at Purdue

    OpenAIRE

    Knapp, Jim

    2013-01-01

    Two case studies will be presented describing sustainable drainage alternatives. The processes used for the 2nd Street project in Seymour will provide a comparison of the design processes for conventional and green infrastructure solutions. Purdue University will discuss a number of permeable pavement installations on campus and provide a map for viewing. Asphalt, concrete, and permeable paver options will be discussed.

  19. Pervious Pavement System Evaluation

    Science.gov (United States)

    Pervious pavement is a low impact development stormwater control. The Urban Watershed Management Branch of the U.S. Environmental Protection Agency in Edison, NJ, is evaluating concrete pavers as a popular implementation. The pollutant removal of a bench-scale permeable interlo...

  20. 谈橡胶沥青混凝土路面的施工%On construction of rubber asphalt concrete pavement

    Institute of Scientific and Technical Information of China (English)

    李义

    2012-01-01

    Combining the working experience,the paper introduces the construction technique of the rubber asphalt concrete pavement by taking some projects as the example,and illustrates the operation points for some key procedure,including the mixing of the rubber asphalt,the transportation,the paving,and the roller compaction,so as to direct the practice.%结合自身工作经验,以具体工程为例,介绍了橡胶沥青混凝土路面施工技术,分别阐述了橡胶沥青的搅拌、运输、摊铺、碾压等关键工序的操作要点,以期指导实践。

  1. Skid resistance of bituminous surfaces in Ohio

    Science.gov (United States)

    Colony, D. C.

    1984-03-01

    Statistical studies of skid number (SN) on the state highway system in Ohio reveal apparently systematic variations in distributions of SN among the twelve districts in the state. These variations appear to be significantly related to traffic and to geological characteristics of a given district. Regression calculations using traffic index, a function of ADT and age of the pavement surface in months, show a high correlation with SN, although standard errors of estimate were too large to make the equations useful for predicting SN from traffic variables. Similar results were obtained by elating SN to physiographic features in the state. Pavement surface type (bituminous or pcc) and coarse aggregate type (limestone, gravel or slag) are significantly related to SN.

  2. Bituminization plant Jaslovske Bohunice

    International Nuclear Information System (INIS)

    In this leaflet the principle of the bituminization plant for radioactive concentrate (the intermediate liquid radioactive waste generated during the NPP A1, V-1, V-2 operations) solidification used in the Bohunice Radwaste Treatment Centre (BSC RAO) is presented

  3. 沥青混凝土道面反射裂缝的防治与预控%On prevention and pre-control of reflection cracks of asphalt concrete pavement

    Institute of Scientific and Technical Information of China (English)

    江红义

    2012-01-01

    Combining with the work practice, the paper analyzes the formation mechanism and reasons for the reflection cracks on the asphalt concrete pavement, points out the pre-control measures and treatment methods for the reflection cracks, and proves by the engineering example that the application of the prevention technique can reduce the reflection cracks and enhance the stability of the asphalt concrete pavement.%结合工作实践,分析了沥青混凝土道面反射裂缝的产生机理及产生原因,提出了反射裂缝的预控措施和治理方法,通过工程实例证明该防治技术的应用减少了反射裂缝,增强了沥青混凝土面层的稳定性。

  4. Design of Pervious Concrete Pavement and Constructed Wetland System for Rainwater Collection and Treatment%透水混凝土路面/人工湿地雨水收集处理系统的设计

    Institute of Scientific and Technical Information of China (English)

    吴文伶; 宋中南; 石云兴; 罗兰; 王珂; 戢文占; 张涛; 冯建华; 李艳稳

    2011-01-01

    Pervious concrete pavement for rainwater collection and constructed wetland for rainwater treatment are used in a rainwater collection and utilization project in Lisui town of Shunyi District, Beijing City. The design methods of pervious concrete pavement, detention tank and constructed wetland are introduced. Furthermore, the technology advantages, process flow and structure design are discussed.%北京市顺义区李遂镇某雨水收集利用工程采用透水混凝土路面收集雨水并应用人工湿地进行雨水处理,详细介绍了透水混凝土路面、调节池、人工湿地的设计方法,并对该技术的优势、工艺流程、结构设计等进行了详细探讨.

  5. 基于累积损伤因子的水泥混凝土路面设计%Cement concrete pavement design based on cumulative damage factor

    Institute of Scientific and Technical Information of China (English)

    蔡良才; 朱占卿; 吴爱红; 潘正华; 王维国

    2012-01-01

    Based on the compositive fatigue equation of load fatigue stress and temperature fatigue stress, the coverage-to-pass ratios of single-axle-single-wheel load and single-axle-double-wheel load were calculated by adopting cumulative damage factor. A direct calculating method of total cumulative fatigue damage of pavement structure produced by multi-axle load and a new design method of cement concrete pavement were put forward by replacing design axle load with cumulative damage factor. The accuracy and application feasibility of calculating fatigue damage produced by multi-axle load were done through a design example with two types of traffic volumes. Analysis result indicates that the acting times of multi-axle load at all points on the cross section of highway are different, and the peak value of cumulative damage of each axle load may be not at the same location. The thicknesses of worst pavement places under the traffic volumes calculated by the design method based on cumulative damage factor are all 22 cm, which meets the design requirement, and the thicknesses of other places can reduce according to the cumulative damage curve. Thereby, it can avoid the differences and localizations of present specification design method of concrete pavement based on standard axle load and equivalent fatigue consumption principle. 1 tab, 8 figs, 12 refs.%考虑荷载疲劳应力和温度疲劳应力的综合疲劳方程,计算了单轴单轮及单轴双轮轴载的覆盖通行率,利用累积损伤因子替代标准轴载在交通量换算中的作用,提出了直接计算各级轴载对路面结构总的累积疲劳损伤方法和新的水泥混凝土路面设计方法,并采用两组交通量对轴载累积损伤量的计算方法的准确性与可行性进行了验证。分析结果表明:公路横断面上各点处轴载的作用次数是不同的,各级轴载的累积疲劳损伤峰值不一定在同一位置,利用基于累积损伤因子的水泥混凝土路面设计

  6. 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 ...

  7. Mechanism of Reflection Crack Prevention by Gravel Transformation of Old Cement Concrete Pavement%旧水泥混凝土路面碎石化后防止反射裂缝机理

    Institute of Scientific and Technical Information of China (English)

    罗岩; 张涛

    2011-01-01

    At present, gravel transformation technology is commonly used to prevent reflection crack on asphalt overlay in domestic when cement concrete pavement is out of service or damaged for whatever reason.In this paper, through analyzing the causes of cracks on asphalt overlay that is directly paved on cement concrete pavement, the mechanism of reflection crack prevention by gravel transformation of cement concrete pavement is analyzed.%目前,水泥混凝土路面到达其使用年限,或其他原因遭受破坏需要重建时,国内多采用碎石化工艺来防止沥青罩面反射裂缝的产生.通过对水泥混凝土面板上直接加铺沥青层开裂成因的探讨,分析了水泥混凝土路面经碎石化后防止反射裂缝的机理.

  8. 表面防水处理对机场混凝土道面耐久性的影响%The Impact of Surface Waterproofing Treatment on the Durability of Airport Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    朱剑; 袁捷

    2011-01-01

    文章通过抗渗、冻融、化学侵蚀试验及现场摩擦系数测试,研究了涂刷两种新型混凝土保护剂进行表面防水处理对机场混凝土道面耐久性的影响。结果表明:两种混凝土保护剂均能大幅改善混凝土的抗渗性能,降低混凝土冻融后的动弹性模量损失以及道面除冰液侵蚀下的强度损失,且不影响道面的抗滑性能。通过涂刷新型混凝土保护剂进行表面防水处理是提高混凝土道面耐久性的有效方法。%Through tests on impermeability,freeze thawing,chemical attack and on field friction factor,the article studied the impact of using two new concrete protective agents to perform surface waterproofing treatment on the durability of airport concrete pavement.The result shows that these two agents can improve the impermeability of concrete,decrease the loss of dynamic modulus of elasticity after freeze thawing and the loss of strength after corrosion caused by deicing fluid.It does not affect the anti-resistance of pavement.It is proved that using the new concrete protective agent to perform surface waterproofing treat-ment is an efficient way to improve the durability of concrete pavement

  9. 粉煤灰地聚合物在水泥混凝土路面修复中的应用研究%Application of Fly Ash Geopolymer in Cement Concrete Pavement Repair

    Institute of Scientific and Technical Information of China (English)

    朱宝权

    2015-01-01

    为解决水泥混凝土路面修补材料存在的路面开放交通时间偏长和耐久性较差的问题,通过进一步实验、研究粉煤灰地聚合物混凝土制备、特性及机理,并将其应用于水泥混凝土路面的快速修补。实验后,粉煤灰地聚合物早期抗弯拉强度高,其力学强度、粘结强度均满足路面修补混凝土的技术要求,在路面快速修补材料中应用前景十分广阔。%To address the problems of a relatively long open transport time and poor durability for cement concrete pave-ment repair material,through further experiments,preparation,characteristics and mechanism of fly ash geopolymer con-crete,it was applied to the quick fix of cement concrete pavement.After the experiments,the anti-flexural-tensile strength of fly ash geopolymer was high at the early stage,and its mechanical strength and bond strength could both meet the tech-nology requirements of pavement mending concrete,which could have broad application prospects in the rapid repair materi-als of pavement.

  10. Pervious Pavement System Evaluation-Paper

    Science.gov (United States)

    The use of a pervious pavement can be effective as a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete paver systems as a type of porous pavement. Although the pavers are impermeable, the spaces between the pave...

  11. On the Cold In-place Recycling of Asphalt Concrete Pavement%浅谈沥青混凝土路面现场冷再生技术

    Institute of Scientific and Technical Information of China (English)

    方建明

    2009-01-01

    In the recovery work of Highway Tongeheng-Zhongyang that was damaged after heavy snow, the technique of cold in-place recycling of asphalt concrete pavement to make the new base was applied. Practice indicates that the quality of the new base meet all technical requirement. The article discusses this technique in terms of censtructinn preparation, construction process and test after coastruetinn.%文章介绍桐城至枞阳段雪灾后恢复项目养护工程中冷再生沥青混凝土基层施工,主要从沥青路面现场冷再生施工准备、施工程序、施工后检测的情况,讨论了沥青路面现场冷再生施工技术,实践证明,其冷再生沥青混凝土基层施工质量达到新建基层的各项技术标准.

  12. Study on Axle Load Conversion for Concrete Base of Durable Asphalt Pavement%耐久性沥青路面混凝土基层轴载换算研究

    Institute of Scientific and Technical Information of China (English)

    郑木莲; 陈拴发; 马庆雷

    2012-01-01

    刚性基层耐久性沥青路面作为一种新型的路面结构,现行规范对于上覆沥青层水泥混凝土路面的设计思路对其并不适用,其轴载换算公式由于没有考虑刚性基层沥青路面结构的特点,得出的结果存在较大误差.依据普通混凝土及贫混凝土的疲劳方程,结合耐久性沥青路面混凝土基层在标准轴载和不同轴-轮型荷载作用下回归得出的荷载应力计算公式,按照混凝土基层等效疲劳损伤原则,推求得出单轴-单轮、单轴-双轮组、双轴-双轮组荷载换算为标准轴载的公式.结果表明:得出的轴载换算公式可充分考虑混凝土基层耐久性沥青路面基层厚度、基层模量、地基模量结构设计参数的影响,具有良好的实用性,可为路面结构设计提供依据.%As a new kind pavement structure, the design method of cement concrete pavement with asphalt surface course in the current specification is not suitable to the durable asphalt pavement with rigid base. Since the characteristics of durable pavement with rigid base are not taken into account, there exists large error in the results getting from the axle-load conversion equation. According to the fatigue equations of popular concrete and lean concrete, the load stress calculation equations rigid base in durable asphalt pavement subjecting standard axle load and different axle-wheel load, and the equivalent fatigue damage principle of concrete base, the axle load conversion equations from the load of single-axle and single-wheel, single-axle and two-wheel and two-axle and two-wheel to the standard axle load are derived. The results show that the axle load conversion equations got in the paper can fully consider the influences of the structure design parameters of base depth, base modulus and subgrade modulus etc. Of durable asphalt pavement with concrete pavement, so the equations have good suitability and can provide basis for pavement structure design.

  13. Pervious Pavement System Evaluation- Abstract 1

    Science.gov (United States)

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  14. Prediction on Permanent Deformation of Silty Clay Subgrade for Cement Concrete Pavement%水泥混凝土路面粉质粘土路基永久变形及其预测

    Institute of Scientific and Technical Information of China (English)

    冯怀平; 蒋闯

    2012-01-01

    In connection with the relationship between cement concrete pavement and permanent deformation of subgrade soil, the requirement of cement concrete pavement against subgrade performance is analyzed from the view of reducing pavement diseases. Moreover, through indoor dynamic triaxial test, the mechanism forming and the factors influencing permanent deformation of such subgrade are analyzed; and based on NCHRP-37A model, the relevant method for prediction is established to subgrade. confirm the permanent deformation of silty clay%针对水泥混凝土路面与路基土永久变形之间的相互关系,从降低路面病害角度出发,分析水泥混凝土路面对路基性能的要求。并通过室内动三轴试验对水泥路面路基永久变形的形成机理和影响因素进行分析,基于NCHRP-37A模型,建立了相应的预估方法,以确定粉质粘土路基永久变形量。

  15. 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.

  16. Pervious Concrete

    OpenAIRE

    Torsvik, Øyvind André Hoff

    2011-01-01

    Pervious concrete is a type of concrete with little or no fines which give a large void. This enables high permeability and because of this it enables water to percolate through the concrete. Pervious concrete have been used in many years both as pavement material and on several other applications in the U.S and in other countries in Western Europe. In Norway pervious concrete is not currently in use. This thesis aims to investigate if pervious concrete can withstand the harsh Norwegian clima...

  17. Calculation of the temperature of asphalt concrete at making the joints of multilane road pavement of non-rigid type

    Directory of Open Access Journals (Sweden)

    Giyasov Botir Iminzhonovich

    2015-03-01

    Full Text Available The construction quality of road surface of non-rigid type essentially depend on providing the temperature regimes in the process of laying and packing of hot asphalt concrete mixtures. In order to provide the required characteristics of asphalt concrete due to the surface width it is necessary to provide the temperature regimes of hot asphalt concrete mixture in the zones of lane connection. The hot mixture is promptly cooling right after laying within several minutes, which results, according to the construction technology and the specific conditions of work production, in temperature abuse of the mixture at joints of the lanes at packing. The authors present the analysis of the technology of arranging multilane road surface by one paver with the possibility of heating the surface lane edge with the temperature of the adjacent lane. The results of the studies of the production conditions effect on the temperature of edge heating of the previously laid lanes, and the time required to achieve the maximum heating temperature depending on the relative thickness of coating layers.

  18. To Guarantee the Quality of Asphalt Concrete Pavement in Road Construction%谈道路施工中沥青混凝土路面的工程质量保障

    Institute of Scientific and Technical Information of China (English)

    邱龙

    2013-01-01

      The road construction project is an important part of the municipal infrastructure construction, and the road construction quality affects the people's daily life and the urban appearance directly. This article will mainly analyze the problems of the asphalt concrete pavement construction in the road construction, and discuss the way to guarantee the quality of pavement construction.%  道路施工工程是城市基础设施建设的重要组成部分,道路施工质量的好坏直接影响着人们的日常生活以及城市的市容。本文将主要就道路施工中沥青混凝土路面施工存在的问题进行分析,就如何对路面施工质量提供保障进行探讨。

  19. Relation between the permeability and strength of cold region pavement concrete%寒冷地区道路混凝土渗透性与强度的关系

    Institute of Scientific and Technical Information of China (English)

    张玫; 潘志忠; 赵化启; 李国晶

    2016-01-01

    Through tests,correlation analysis of strength and permeability of cold region pavement concrete with different W/B,put forward the compressive strength and permeability of ordinary concrete has good correlation,and for the concrete mixed with fly ash,silica fume and air-en-training agent,the linear correlation is not as good.%通过试验,分析了寒冷地区不同水胶比的道路混凝土强度与渗透性的关系,指出普通混凝土的抗压强度与渗透性有较好的相关性,而掺加粉煤灰、硅灰及引气剂的混凝土强度与渗透性相关性较差。

  20. Long-term properties of bituminized waste products

    International Nuclear Information System (INIS)

    This study is a survey of the factors of importance for long term behaviour of bituminized ion exchange resins. Phenomena occurring in bituminized waste products affected by the treatment, storage and disposal are identified. Test methods have been developed for characterizing product properties, which are important for the long-term behaviour. The long-term properties of bituminized ion-exchange resins are studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are ralated to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product. (author)

  1. Long-term properties of bituminized waste products

    International Nuclear Information System (INIS)

    This study is a survey of the factors of importance for the long term behaviour of bituminized ion exchange resins. Phenomena occurring in bituminized waste products affected by the treatment, storage and disposal are identified. Test methods have been developed for characterizing product properties, which are important for the long-term behaviour. The long-term properties of bituminized ion-exchange resins are studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are related to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product

  2. Method of airport concrete pavement design for large military transport aircrafts%适应大型特种飞机的机场水泥混凝土道面结构设计方法

    Institute of Scientific and Technical Information of China (English)

    李巧生; 赵鸿铎; 凌建明

    2011-01-01

    对适应大型特种飞机的机场水泥混凝土道面的损坏模式、设计标准和厚度计算方法进行研究.明确了大型特种飞机荷载重、起落架复杂的特点;三维有限元分析的结果表明,其多轮叠加效应明显,建议在道面结构设计中考虑全起落架荷载.针对大型特种飞机的特点提出以9块板二维有限元模型作为力学分析模型,以板疲劳断裂作为损坏模式,基于累积损伤原理考虑混合交通.基于Miner原理,给出了累积损伤因子CDF的计算公式,并以CDF接近1(道面达到50%的开裂密度)作为道面设计标准.详细分析了不同机型通行一覆盖率的计算方法,以此为基础形成了各机型预期覆盖次数的计算方法.系统对比了国内外的水泥混凝土道面疲劳方程,建议以美国NCHRPI-26提出的疲劳方程作为现阶段构建水泥混凝土道面设计方法的基础,并进一步明确了允许覆盖次数的计算方法.综合提出了适应大型特种飞机的机场水泥混凝土道面结构设计流程.%This paper is about airport concrete pavement design method for large special aircrafts. Based on 3-D FEM analysis, full landing gear is recommended for pavement design. Considering the characteristics of large special aircrafts,a 3-D FEM model with 9 concrete slabs is employed for pavement design. Fatigue crack is taken as a damage pattern,and a cumulative principle is recommended to consider mixed traffic. Based on Miner's principle, the functions of calculating CDF are given. CDF = 1 is accepted as the design criteria of concrete pavement, which indicates 50% crack density. The P/C (pass to coverage ratio) calculation functions are put forwarded for various aircrafts, and the equation for calculating the expected coverage is developed. Various fatigue functions of airport concrete pavement are compared.The functions developed by NCHRP 1-26 are accepted as the fatigue functions to calculate the allowable coverage of

  3. 再生混凝土粒料在路面降噪中的应用研究%Application Research on Recycled Concrete Aggregates Used in Low-noise Pavement

    Institute of Scientific and Technical Information of China (English)

    阮志刚

    2014-01-01

    This paper introduces the use of recycled concrete aggregates to replace part of the natural coarse aggregate porous asphalt concrete mixing to explore the feasibility of recycled concrete aggregates used in low-noise pavement. Using high viscosity modified asphalt and cement asphalt paste two bonding porous asphalt concrete mixing material specimens, this paper discusses in two stages recycled concrete aggregates used in the feasibility of low noise pavement. The results show that the study of asphalt cement mortar as a binder, mixing porous asphalt concrete mixing temperature is not required, which can effectively reduce air pollution and energy consumption, and the mechanical properties, durability and road performance is good.%采用废弃混凝土再生集料取代部分天然粗集料拌制多孔隙沥青混凝土,以探讨废弃混凝土再生集料应用于低噪声路面的可行性。研究时采用高黏改性沥青及水泥沥青胶浆两种黏结料拌制多孔隙沥青混凝土试件,并分两阶段探讨废弃混凝土再生集料应用于低噪声路面的可行性。研究表明,采用水泥沥青胶浆作为黏结料拌制多孔隙沥青混凝土无须高温拌合,可有效降低空气污染及能源消耗,具有较好的力学性质、耐久性质及路用性能。

  4. 8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials

    CERN Document Server

    Partl, Manfred

    2016-01-01

    This work presents the results of RILEM TC 237-SIB (Testing and characterization of sustainable innovative bituminous materials and systems). The papers have been selected for publication after a rigorous peer review process and will be an invaluable source to outline and clarify the main directions of present and future research and standardization for bituminous materials and pavements. The following topics are covered: - Characterization of binder-aggregate interaction - Innovative testing of bituminous binders, additives and modifiers - Durability and aging of asphalt pavements - Mixture design and compaction analysis - Environmentally sustainable materials and technologies - Advances in laboratory characterization of bituminous materials - Modeling of road materials and pavement performance prediction - Field measurement and in-situ characterization - Innovative materials for reinforcement and interlayer systems - Cracking and damage characterization of asphalt pavements - Rec...

  5. The Gravel Construction Technology and Quality Control of Cement Concrete Pavement%水泥混凝土路面碎石化施工工艺及质量控制

    Institute of Scientific and Technical Information of China (English)

    王方河

    2013-01-01

    The technology of rubblization is an important me-ans to overhaul of cement concrete pavement, which broke the cement concrete pavement into smal interlocking particles to provide ideal primary for the new asphalt concrete overlay. In this article, the author bases on the example of rebuild project of G312 Luan, and talk about some ideas on the gravel constr-uction technology and quality control.%  碎石化技术是水泥混凝土路面大修改造的重要手段,该技术通过将水泥混凝土路面破碎成小粒径嵌挤颗粒,从而为新的沥青混凝土加铺层提供理想的基层。本文主要结合G312六安段改建工程的实际情况,对碎石化施工工艺及质量控制谈一点心得。

  6. 含脱空水泥混凝土路面交通荷载下的疲劳损伤机理%Fatigue damage mechanism of cement concrete pavement with void under traffic load

    Institute of Scientific and Technical Information of China (English)

    薛彦卿; 黄晓明; 石小武; 马涛

    2014-01-01

    In order to obtain the fatigue damage mechanism of cement concrete pavement with void under traffic load,the user subroutine UMAT (user-defined material mechanical behavior) in ABAQUS for the fatigue damage constitutive relation is compiled.Then,the distribution law and the development law of the fatigue damage field of the standard pavement structure model by the fully coupled approach are analyzed.Finally,the influences of traffic load and the pavement structural pa-rameters such as the slab elasticity modulus,slab thickness and void size on the crack formation fa-tigue life of the cement concrete pavement structure are researched.The results show that with the increase in the number of load cycles,the degree of fatigue damage of pavement structure increases continuously while its increment rate decreases.Meanwhile,the load stress in the pavement structure also decreases gradually.With the increase of the traffic load,the natural logarithm of the pavement structural fatigue life decreases linearly.With the increase of the slab thickness,the natural logarithm of the pavement structural fatigue life increases linearly.With the increase of the void size,the natu-ral logarithm of the pavement structural fatigue life exhibits a decline curve of the power function.%为获得含脱空水泥混凝土路面交通荷载下的疲劳损伤机理,开发了疲劳损伤本构关系的ABAQUS用户子程序UMAT,分析了全耦合方法下基准路面结构模型疲劳损伤场的分布与发展规律,并研究了交通荷载与面板弹性模量、面板厚度、脱空尺寸等路面结构参数对水泥混凝土路面结构裂纹形成疲劳寿命的影响。研究结果表明,随荷载作用次数的增加,路面结构的疲劳损伤不断增加,但其增幅逐渐减小,路面结构的荷载应力也逐渐减小。随着交通荷载的增加,路面结构的对数疲劳寿命呈线性减小趋势;随着面板厚度的增加,路面结构的对数疲劳寿命

  7. 层布式钢纤维混凝土复合路面设计研究%Research on composite pavement design of layered steal fiber reinforced concrete

    Institute of Scientific and Technical Information of China (English)

    范小春; 余煜; 潘文杰; 汪俊彦

    2015-01-01

    层布式钢纤维混凝土结构具有优良的抗弯拉性能,可有效降低普通混凝土路面板板厚.通过有限元软件ANSYS,构建了层布式钢纤维混凝土路面(LSFRCP,Layered Steel Fiber Reinforced ConcretePavement)、层布式混杂纤维混凝土路面(LHFRCP,Layered Hybrid Fiber Reinforced Concrete Pavement)和层布式钢纤维柔性混凝土路面(LSFFCP,Layered Steel Fiber Flexible Concrete Pavement)的有限元计算的模型;研究了路面板的板长与板厚和基体混凝土弹性模量在行车荷载、温度作用下的变化规律:荷载应力随板长的增加先降低后增加,随板的厚度的增加而降低;荷载应力和温度应力随基体混凝土弹性模量的增加而增加;温度应力随着板长和板厚的增加先增加后降低.给出了LSFRC、LHFRC和LSFFC复合路面板设计的主要思路;编制了不同路面板长在不同交通等级下的最小板厚表.

  8. Update to permeable pavement research at the Edison Environmental Center - slides

    Science.gov (United States)

    Abstract: The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable...

  9. Update to Permeable Pavement Research at the Edison Environmental Center - abstract

    Science.gov (United States)

    Abstract The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable ...

  10. 水泥混凝土路面实测FWD数据与表观路况关系探讨%Relationship between FWD Data and Visual Survey Conditions for Cement Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    苏卫国; 卢辉

    2007-01-01

    The main areas that can be evaluated by Falling Weight Deflectometer (FWD) testing of PCC (Portland Cement Concrete) pavement includes: joint load transfer, voids under the slabs, roadbed' s strength, slab's rigidity,uniformity of strength for the subgrade and pavement. At present, researchers have developed many evaluation models with the FWD testing data; however, few of them are practical. The main problem is lack of basic in-situ data, so none of the models are feasible without excessive field testing. Based on FWD field testing data and a large number of pictures of a highway, analyzed the relationships between values derived from FWD measurement in-situ and pavement condition data which was collected by means of field visual surveying or testing on an existing PCC pavement of a highway. Some qualitative or quantitative methods for obtaining joint load transfer and pavement stiffness and load-bearing capacity of the existing PCC slab were discussed. The concept of evaluating the overall load-bearing capacity of the pavement structure with a summation of FWD deflections in center of the loading plate is proposed.%采用落锤式弯沉仪(FWD)实验数据评价旧水泥混凝土路面的主要范围包括:接缝传荷能力、板底脱空判别、路基强度、混凝土板体刚度、路基路面强度的均匀性等.目前,研究者建立了许多采用FWD数据的评价模型,但实用性欠佳,主要问题在于缺乏基础性的现场实测数据,因而模型的可靠性较差.文中基于某国道水泥混凝土路面的FWD实测数据及大量路况表观调查照片,分析FWD实测参数与旧水泥混凝土路面状况调查实录及测试数据间的某些相关性,探索旧水泥混凝土板的接缝传荷能力、弯曲刚度、综合承载能力等定性或定量的判别方法,提出利用FWD加载中心弯沉值总水平评价旧水泥混凝土路面综合承载能力的设想.

  11. 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.

  12. Effect of Concrete Pavement Plastering and Maintenance with Cold Water on Early Cracks%混凝土道路抹面和冷水养护对早期裂缝的影响

    Institute of Scientific and Technical Information of China (English)

    岑国平; 洪建军; 孙程光; 张文华; 张拓

    2011-01-01

    To reduce the quantities of the early cracks in concrete pavement, the concrete plastering process and maintenance with cold water are tested. The concrete mix proportion design and optimization of raw materials are introduced. The influences of different plastering numbers to concrete crack resistance are compared. Because the water is very cold in Tibet plateau area, composite non-woven fabric is used to maintain concrete. The result shows that two methods are very useful and the quantities of early cracks can be reduced successfully.%为了减少混凝土道面的早期收缩裂缝,对道面施工过程中抹面工艺和冷水养护环节进行室内试验.首先确定试验的原材料和配合比,进而比较了不同抹面次数对混凝土抗裂性的影响;针对青藏高原地区养护用水温度过低问题,采用复合无纺布土工膜覆盖养护技术解决了此难题.试验结果表明,这两种方法都可以有效减少早期裂缝地产生,值得推广.

  13. The mix design and construction technology of pervious cement pavement concrete%透水水泥路面混凝土配合比设计及施工技术

    Institute of Scientific and Technical Information of China (English)

    肖菁

    2011-01-01

    Pervious cement pavement concrete is of good perviousness,it can release the problems of highway seeper and urban environment,so it is a sort of environmental protection concrete.The material selection,mix design and construction technology of pervious ce%透水水泥路面混凝土具有良好的透水性,能够缓解公路积水和城市环境问题,是一种环保型的混凝土。本文讨论了透水水泥路面混凝土的原材料选择、配合比设计及施工工艺,并展望了透水水泥路面混凝土的应用前景。

  14. Thermal stability analysis under embankment with asphalt pavement and cement pavement in permafrost regions.

    Science.gov (United States)

    Junwei, Zhang; Jinping, Li; Xiaojuan, Quan

    2013-01-01

    The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results. PMID:24027444

  15. 除冰剂对机场跑道混凝土抗冻性能影响%Effects of deicing agent on freezing resistance of airfieId pavement concrete

    Institute of Scientific and Technical Information of China (English)

    陈继超; 李玉香; 朱晓燕; 郑召; 付玉龙

    2015-01-01

    The freezing resistance of airport pavement concretes which were immersed in different concentrations of ethylene glycol so-lution was investigated by single side freezing-thawing method,and the amount of samples′s caling was regarded as evaluation parame-ters of the freezing-thawing durability of concrete. Results show that the freezing-thawing damage is the most serious in low salt con-centrations,and when the concentration of ethylene glycol was 3%,freezing-thawing damage reaches the maximum;By the failure mechanism of airport pavement concrete analysis,the damage was significantly affected by the concrete bibulous rate and deicing agent itself freezing inflation rate.%采用单面冻融法,以试件表面剥落量作为混凝土抗冻性能的评定参数,探讨了经不同浓度乙二醇溶液浸泡后的机场道面混凝土的抗冻性能。结果表明,混凝土经中低浓度乙二醇溶液浸泡后,冻融破坏严重,当乙二醇浓度为3%时,冻融破坏达最大值;通过机场道面混凝土破坏机理分析,破坏主要受混凝土中溶液吸入率、除冰剂自结冰膨胀率影响显著。

  16. Permeable pavement research – Edison, New Jersey

    Science.gov (United States)

    These are the slides for the New York City Concrete Promotional Council Pervious Concrete Seminar presentation. The basis for the project, the monitoring design and some preliminary monitoring data from the permeable pavement parking lot at the Edison Environmental Center are pre...

  17. Comparative Durability Analysis of Asphalt Concrete Pavement Reinforced with Two Geosynthetics%两种土工合成材料加筋沥青混凝土路面耐久性对比分析

    Institute of Scientific and Technical Information of China (English)

    何勇海

    2012-01-01

    土工合成材料加筋沥青混凝土路面结构可以提高其疲劳寿命、抗反射裂缝和抗高温车辙能力,成为沥青路面路用技术性能改善的一个有效途径.通过室内试验系统研究了无加筋层、中间加铺玻纤土工格栅或聚酯玻纤布加筋沥青混凝土的低温抗裂性、高温稳定性和抗疲劳性能.试验结果表明,聚酯玻纤布加筋结构具有较好的低温抗裂性能,而玻纤格栅加筋结构的高温稳定性较好.%The asphalt concrete pavement structure reinforced with synthetics can improve the fatigue life, reflective crack resistance and high temperature rut resisting ability. This technique has become an effective way for improvements of road performance of the asphalt pavement. The laboratory test of low temperature resistance, the high temperature stability and anti-fatigue performance are done with the ordinary asphalt concrete pavement structure, reinforced with glass fiber geogrid or polyester glass fiber cloth glass. The test results show that polyester glass fiber cloth reinforcing structure has good low temperature crack resistance energy, while glass fiber reinforcement grid structure has good high temperature stability.

  18. Mechanical Response Analysis of Asphalt Pavement Structure

    Directory of Open Access Journals (Sweden)

    Yu Zhenqing

    2015-11-01

    Full Text Available Generally, the Chinese designed life of the high- grade asphalt concrete pavement is required 15 years, however, the designed life of the road in surface is often lower than the designed life, and even premature failure. Especially in heavy traffic conditions, the early damage of some high grade-asphalt pavement in China is serious. According to some investigations, we founded the main reason of the long-life asphalt pavement is to determine the function of each structure layer. According to the stress of pavement structure layer, so as to select the structure layer materials. Based on the viewpoint of mechanics, asphalt pavement damage mode is divided into three categories, such as top-down crack, fatigue cracking and rutting. Therefore, this paper uses ANSYS finite element software as calculation tool, the combination of road vehicle load and the primary influence on asphalt pavement structure mechanics response characteristics were analyzed. In this paper, the method of analysis is control variable: that means under different vehicle axle load, only change surface layer modulus and observe the pavement structure mechanical response trends to compare the effect. By using the same method, the response of the pavement base course parameters to the pavement mechanical structure is analyzed.

  19. Application Research on Preventing Measures against Reflection Cracks of Asphalt Concrete Surface Covering Old Cement Pavement%旧水泥路面沥青加铺层防反射裂缝措施的应用与分析

    Institute of Scientific and Technical Information of China (English)

    张泽鹏; 王钊

    2014-01-01

    In this paper,the five common prevention measures against reflection crack that produced in asphalt concrete pavement covering an old cement concrete pavement have been introduced,including self-adhesive belt, thermal bonding belt,SAMI stress absorbing layer,geotextile and glass fiber grid. Through indoor fatigue tests and outdoor tests,comparison and analysis on application characteristic of the five prevention measures have been put forward.%针对旧水泥混凝土路面沥青加铺层结构中自粘式压缝带、热粘式压缝带、SAMI 应力吸收层、土工布及玻纤格栅等常用的五种延缓反射裂缝的处理措施,通过对其进行室内疲劳试验分析和室外试验评价,对比分析这五种处理措施的应用特点。

  20. 沥青混凝土路面就地热再生施工工艺探讨%Discussion on Construction Process of Hot In -Place Recycling Technology of Asphalt Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    徐安花; 房建宏

    2015-01-01

    Hot in-place recycling technology of asphalt concrete pavement ,w hich has broad application prospects ,has significant economic and technical advantages in waste utilization ,resource saving ,ecological environmental protecting ,etc .In this paper ,in order to provide guidance to site construction of hot in -place recycling technology ,the essential points and attentions of the construction process of hot in -place recycling technology of asphalt concrete pavement are analyzed from its technological type ,heating method ,scarifying method ,adding mode of additive and construction process .%沥青混凝土路面就地热再生技术在废料利用、资源节约和生态环境保护等方面具有显著的技术和经济优势,具有广阔的应用前景。本文从沥青混凝土路面就地热再生主要工艺类型、加热方式、翻松方式、再生剂添加方式及施工过程等方面分析了沥青路面就地热再生技术施工工艺方面的要点及注意事项,以期为就地热再生技术的现场施工提供指导。

  1. Reuse of steel slag in bituminous paving mixtures.

    Science.gov (United States)

    Sorlini, Sabrina; Sanzeni, Alex; Rondi, Luca

    2012-03-30

    This paper presents a comprehensive study to evaluate the mechanical properties and environmental suitability of electric arc furnace (EAF) steel slag in bituminous paving mixtures. A variety of tests were executed on samples of EAF slag to characterize the physical, geometrical, mechanical and chemical properties as required by UNI EN specifications, focusing additionally on the volumetric expansion associated with hydration of free CaO and MgO. Five bituminous mixtures of aggregates for flexible road pavement were designed containing up to 40% of EAF slag and were tested to determine Marshall stability and indirect tensile strength. The leaching behaviour of slag samples and bituminous mixtures was evaluated according to the UNI EN leaching test. The tested slag showed satisfactory physical and mechanical properties and a release of pollutants generally below the limits set by the Italian code. Tests on volume stability of fresh materials confirmed that a period of 2-3 months is necessary to reduce effects of oxides hydration. The results of tests performed on bituminous mixtures with EAF slag were comparable with the performance of mixtures containing natural aggregates and the leaching tests provided satisfactory results. PMID:22305201

  2. Cold bituminous mixes

    OpenAIRE

    Delak, Boštjan

    2012-01-01

    Asphalt mix (short also asphalt) can be obtained from nature (natural asphalt) or produced technically (artificial asphalt), i. e. as a mix of bituminous binder, stone grain, and other additives that improve the asphalt properties. The beginnings of the use of asphalt can be traced from 6,000 to 4,000 BC since people back then knew some materials that contained bitumen as a binder. A more frequent use of the natural asphalt, however, starts around 3,000 BC. Different peoples used it primar...

  3. Temperature induced healing in strained bituminous materials observed by atomic force microscopy

    NARCIS (Netherlands)

    Nahar, S.N.; Schmets, A.J.M.; Scarpas, A.; Schitter, G.

    2013-01-01

    Bitumen is the binder in the composite material named asphalt concrete. Under cyclic mechanical loading of traffic passing over the pavement, eventually damage will initiate in the pavement, leading to eventual structural failure. This damaging process is accelerated by time dependent change of the

  4. Typical Structure of Bridge Deck Asphalt Pavement of Cement Concrete Bridge%水泥混凝土桥沥青铺装典型结构研究

    Institute of Scientific and Technical Information of China (English)

    何德云; 熊欣; 董强

    2011-01-01

    Vehicle's safety and comfort has been directly affected by the quality of bridge deck pavement, and the quality of bridge deck pavement has been directly affected by the composite structure of bridge deck pavement. Through the interlayer cohesive tests with 7 sorts of materials, temperature stability and fatigue bending tests with 3 composite structures, the performance sequence of interlayer cohesive materials and asphalt composite structures have been confirmed. On the basis of the test results, the typical structure of bridge deck pavement has been proposed, which offers references for the design and construction of bridge deck pavement.%桥面铺装的质量直接影响着行车的安全性和舒适性,桥面铺装的结构组合又直接决定了桥面铺装的质量.通过对7种桥面铺装层材料的层间黏结性能试验、3种桥面铺装组合结构的温度稳定性试验和复合小梁弯曲疲劳试验,确定了桥面铺装层间黏结材料和沥青铺装结构的性能排序,在此基础上提出了桥面铺装的典型结构型式,可为桥面铺装设计和施工提供参考.

  5. 机场水泥混凝土道面隔离式加铺层板厚合理性分析%Rationality analysis on thickness of the cement concrete seclusion type pavement overlay

    Institute of Scientific and Technical Information of China (English)

    李清浩; 翁兴中; 颜祥程; 苏建康; 贾建强

    2012-01-01

    通过实例,对机场水泥混凝土道面隔离式加铺层厚度与疲劳应力的关系进行分析,发现旧水泥混凝土道面疲劳应力随着加铺层厚度增加而减小,而加铺层疲劳应力却出现一个峰值.分析了旧道面不同计算厚度与加铺层疲劳应力峰值出现点对应的加铺层厚度的关系,提出当旧道面计算厚度小于20 cm时,加铺层厚度应比综合疲劳应力峰值对应的厚度大1~2 cm;当旧道面计算厚度大于20 cm时,加铺层厚度应比综合疲劳应力峰值对应的厚度小1 ~2 cm,为机场道面隔离式加铺设计提供参考.%The connection between the fatigue stress and the thickness of the seclusion type overlay was analyzed according to a project example.it can conclude that the fatigue stress of the old airport pavement was reduced while the thickness of the seclusion type overlay was increased,but the fatigue stress of the overlay reached to a peak value. Then the connection between the peak fatigue stress and the different design thickness of the old airport pavement was analyzed, it indicated that when the design thickness of the old concrete pavement is less than 20cm, the thickness of the overlay will be 1 - 2 cm more than the thickness of the peak fatigue stress, otherwise it is 1 ~ 2 cm less, and it can offer a reference for the design of the cement concrete seclusion type pavement overlay.

  6. Dynamic Response Analysis with 3D Finite Element Method for Two Typical Kinds of Asphalt Concrete Pavements with Saturated Asphalt Layer%两种典型沥青混凝土路面结构沥青层饱水状态动力响应三维有限元分析

    Institute of Scientific and Technical Information of China (English)

    任瑞波; 祁文洋; 徐强

    2011-01-01

    水和动态荷载耦合作用是沥青混凝土路面发生水损害的主要原因.首先基于多孔介质理论,假定路面结构中的沥青混凝土材料为完全饱水的多孔介质材料,对两种典型路面结构--半刚性沥青混凝土路面、具有柔性基层的半刚性沥青混凝土路面分别建立了三维有限元模型;而后对比分析了两种路面结构在动态荷载作用下的竖向应力、竖向应变、孔隙水压力的空间分布情况以及时程变化规律.结果表明:具有柔性基层的半剐性沥青混凝土路面结构具有较好的抗水损害性能,半刚性沥青混凝土路面结构则表现出较差的抗水损害性能.%The coupled moisture-loading action is the primary factor of initial failure for asphalt concrete pavement. At first, based on the porous media theory , assuming the asphalt concrete as saturated porous media material,two three-dimensional finite element models are established for two typical kinds of asphalt concrete pavements which included the semi-rigid base asphalt concrete pavement, the semi-rigid base asphalt concrete pavement with flexible base. Then the comparison and analysis of the spatial distribution and time change regulation for asphalt concrete pavement between the two kinds of structures are carried out which included vertical stress, vertical strain, and pore pressure. The result indicates that the semi-rigid asphalt concrete pavement stucture with flexible base shows the best performance of resisting the moisture damage, relatively the semi-rigid asphalt pavement structure gives the worse performance.

  7. Utilization of Electronic Waste Plastic in Concrete

    OpenAIRE

    Vivek S. Damal; Saurabh S. Londhe

    2015-01-01

    In India, bitumen pavements are commonly used for highways. Due to the increasing traffic intensity, distress such as rutting and cracking of pavements are very common in Indian roads. Under varying seasonal temperature, flexible pavements tend to become soft in summer and brittle in winter. Investigations revealed that properties of concrete can be better than bitumen roads. But now a day‟s concrete roads are used commonly because concrete roads have more life span than the bi...

  8. Mechanistic design concepts for conventional flexible pavements

    Science.gov (United States)

    Elliott, R. P.; Thompson, M. R.

    1985-02-01

    Mechanical design concepts for convetional flexible pavement (asphalt concrete (AC) surface plus granular base/subbase) for highways are proposed and validated. The procedure is based on ILLI-PAVE, a stress dependent finite element computer program, coupled with appropriate transfer functions. Two design criteria are considered: AC flexural fatigue cracking and subgrade rutting. Algorithms were developed relating pavement response parameters (stresses, strains, deflections) to AC thickness, AC moduli, granular layer thickness, and subgrade moduli. Extensive analyses of the AASHO Road Test flexible pavement data are presented supporting the validity of the proposed concepts.

  9. Construction Technology of Pervious Concrete Pavement in Daxing Xincheng Forest Park%大兴新城滨河森林公园透水混凝土路面施工技术

    Institute of Scientific and Technical Information of China (English)

    戢文占; 石云兴; 张涛; 廖娟; 张楠; 王宝华; 华成谋; 刘伟

    2014-01-01

    和普通混凝土相比,透水混凝土具有使雨水透过路面从而补充地下水的功能,同时具有吸声降噪、缓解城市“热岛效应”等诸多优点。北京大兴新城滨河森林公园内进行了大面积的彩色透水混凝土路面的施工,针对透水混凝土的特点,介绍了配合比设计方法及施工技术。经过检测,混凝土的强度等级达到C25,透水性>2mm/s,抗冻性>D50,道路各项指标满足国家标准的要求,路面效果与周围景观相辅相成,是大面积透水混凝土的一次成功应用。%Compared with ordinary concrete, pervious concrete has the water through the pavement to replenish groundwater, and it also has the advantages of sound absorption and noise reduction, easing the heat island effect of city. Beijing Daxing Xincheng Forest Park applies large⁃area colorful pervious concrete. According to the characteristics of the pervious concrete, the mix ratio design method and construction technique are introduced. After testing, the strength grade of concrete reaches C25, permeability is greater than 2mm/s, frost resistance is greater than D50, all the indexes of road meet the requirements of the national standard. Surface effect and the surrounding landscape complement each other. The project is a successful application of large area of pervious concrete.

  10. 78 FR 26847 - Including Specific Pavement Types in Federal-aid Highway Traffic Noise Analyses

    Science.gov (United States)

    2013-05-08

    ... Federal Highway Administration Including Specific Pavement Types in Federal-aid Highway Traffic Noise...: The FHWA requests input from stakeholders and interested parties on expanding the specific pavement... data from three pavement types: dense-graded asphaltic concrete (DGAC), open-graded asphaltic...

  11. 适应未来大型飞机的水泥混凝土道面设计方法%Airport concrete pavement design for large aircraft in future

    Institute of Scientific and Technical Information of China (English)

    吴爱红; 蔡良才; 顾强康; 李光元

    2011-01-01

    The present concrete pavement design specification uses design aircraft to convert the traffic of other aircrafts into traffic of design aircraft according to the principle of equivalent damage, and it assumes that the wheel path in the lane of runway follows uniform distribution. Actually, wheel path follows the normal school, landing gear of new large aircraft becomes more complex, the peak value of cumulative damage of each aircraft maybe not at the same location, shortages of conversion method using design aircraft is increasing. Based on the wheel path in the lane of runway follows the normal school, pass-to-coverage ratio is used to calculate passes number. Design aircraft's function is replaced by cumulative fatigue damage of pavement structure, which produced by all kinds of aircrafts is carried out directly. A new design method for concrete pavement based on cumulative fatigue damage is discussed and a design example is given. It is approved that the pavement design method using cumulative fatigue damage as design index is more suitable for concrete pavement design of large aircraft with complex landing gear.%现行水泥混凝土道面设计规范,采用“设计飞机”按疲劳等效原则将各型飞机的作用次数换算成“设计飞机”的作用次数,并假定飞机轮迹在通行宽度内均匀分布,实际上飞机轮迹在跑道横断面上服从正态分布.未来大型飞机的起落架更加复杂,各型飞机对道面的累积疲劳损伤峰值不在同一位置,采用“设计飞机”换算的方法日益暴露出不足.按轮迹服从正态分布采用覆盖通行率计算覆盖作用次数,用累积疲劳损伤替代了“设计飞机”在交通量换算中的作用,直接计算各型飞机对道面结构总的累积疲劳损伤,探讨了基于累积疲劳损伤的道面设计方法.实例分析表明:采用累计疲劳损伤作为设计指标的道面设计方法计算结果更精确,更适合未来

  12. The Albedo of Pervious Cement Concrete Linearly Decreases with Porosity

    OpenAIRE

    Rui Zhang; Guosheng Jiang; Jia Liang

    2015-01-01

    Pervious pavements have been advocated as a potential countermeasure to the urban heat island effect. To understand if pervious pavements stay cooler than conventional pavements, the albedo of the pervious concrete must be understood. This study measured the albedo of pervious concrete with different porosity. Four Portland cement concrete mixes were casted, using designed amounts of sand to vary the porosity of the pervious concrete samples. The samples were sliced and the spectral reflectan...

  13. Design and Model Test of Cement Concrete Pavement Slab Based on Phase Change and Temperature Control%相变控温水泥混凝土路面板设计及模型试验

    Institute of Scientific and Technical Information of China (English)

    高英力; 胡柏学; 贺敬; 杨文剑

    2011-01-01

    Based on the phase change energy storage material and functionally-graded material design method, the conventional structure of cement concrete pavement slab was designed for enhancing the function of anti-freezing and wear-resistance, and the model test of pavement slab was carried out. The step cooling test method was adopted to select the composite phase change material, and then it was placed in the high-strength seamless steel pipe. The size of the formed cement concrete pavement slab model was 500 mm × 400 mm × 80 mm. Anti-freezing and wearresistance property test of the model was carried out. Results indicate that phase change temperature point of the selected phase change material is about 5 ℃, and at the point, the liquidsolid phase transition happens to reject heat which can play better ice-melting effect and delay or control the low-temperature freezing phenomena of the pavement slab model surface. The wearresistance of the pavement slab surface material is excellent and its 28-day wear rate is only 51.9% of the standard limited value. The reinforced role of steel pipe in the phase change function layer can prevent the problem of inconsistent volume deformation between the main structure layer and surface layer and also can enhance interface stability.%引入相变储能材料及梯度功能材料设计方法,对传统水泥混凝土路面板结构进行防冻、耐磨功能设计,开展路面板模型试验研究.采取步冷试验方法,将优选出的复合相变储能材料封装入高强度无缝钢管中,制成500 mm×400 mm×80 mm的水泥混凝土路面板模型,进行模型的防冻性能和耐磨性能试验.结果表明:优选的相变材料体系相变温度点可控制在5℃左右,并产生液-固相变过程,放出热量,起到了较好的融冰效果,延缓或控制了路面板模型表面的低温冰冻现象;表面层材料耐磨性优良,28 d磨耗率仅为标准限值的51.9%;相变功能层中钢管的加筋作用可防止主

  14. 水泥混凝土桥梁长寿命桥面铺装层复合结构疲劳特性%Fatigue Performance of Composite Structure for Perpetual Pavement on Cement Concrete Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    钱振东; 王江洋; 王亚奇

    2012-01-01

    In order concrete bridge, to design the perpetual pavement with excellent fatigue behavior for the cement based on the characteristics required for perpetual road pavement, three composite structures were tested with four-point flexural bending test to investigate fatigue properties based on the Weibull distribution theory. The double-logarithm fatigue equations for perpetual pavement were established. The results show that the fatigue lives of three composite structures follow the double-parameter Weibull distribution. With the failure probability of 0.1, the fatigue performance of composite structure, when the lower layer is AC while the lower layer uses epoxy asphalt mixture (EAM) as a substitute for stone mastic asphalt (SMA), is improved significantly. In addition, the fatigue performance of composite structure, when the lower layer is EAM while the upper layer uses SMA as a substitute for asphalt concrete (AC), is improved more. The combination structure of EAM and SMA has the best fatigue performance, and totally satisfies the structure design feature requirement for perpetual pavement. The research results provide a reliable foundation for the further study of the perpetual bridge deck pavement.%为了构建疲劳性能优异的水泥混凝土桥梁长寿命铺装结构,借鉴长寿命沥青路面设计的基本思路,选取3种铺装复合结构方案,采用应变控制的四点弯曲疲劳试验,并基于Weibull分布理论对复合结构的疲劳特性进行分析,建立长寿命桥面铺装复合结构双对数疲劳预估方程。研究结果表明:3种铺装复合结构的疲劳寿命均服从双参数Weibull分布;在失效概率为0.1时,复合结构上面层同为AC,下面层采用环氧沥青混合料(EAM)代替SMA后,其疲劳性能得到提高,复合结构下面层同为EAM,上面层采用SMA代替AC后,疲劳性能得到再次提高;"EAM+SMA"的组合具有较好的抗疲劳性能,同时满足长寿命桥面铺装的结构最优设

  15. Environmentally friendly pavements: Results from noise measurements 2005-2008

    OpenAIRE

    Berge, Truls Svenn; Haukland, Frode; Ustad, Asbjørn

    2009-01-01

    CPX-measurements (tyre A) have been performed on a wide range of ordinary dense Norwegian road pavements and special test pavements, as part of the R&D project “Environmental friendly pavements” initiated by the Norwegian Public Roads Administration. The following conclusions can be made from the investigation:- New dense asphalt concrete pavements can give a tyre/road noise level (CPX) of 4-8 dB(A) lower noise level, compared to a chosen reference level for a pavement of type AC 0/11 and SMA...

  16. 路面多孔水泥混凝土制备技术研究综述%Summary of manufacturing technology for porous cement concrete applied in highway pavement

    Institute of Scientific and Technical Information of China (English)

    陈瑜; 吴学毅

    2009-01-01

    介绍多孔混凝土原材料选择、工作性试验与评价方法及室内成型工艺等方面研究现状.针对路面多孔混凝土存在的问题,提出多孔混凝土制备技术的实质即成功控制多孔混凝土在不同阶段的目标孔隙率和理想孔隙状态,并就最佳目标孔隙率、骨架-孔隙结构的增强和改性、路面构造参数优化及基于目标孔隙率的配合比设计方法等关键问题,综述自身研究成果,具有较大的参考价值.%Researches on constituent materials, workability test and evaluation, as well as indoor molding craft of porous concrete are scientifi-cally introduced.Moreover,aimed at the existing problems of porous concrete applied in highway pavement at present,an opinion manufacturing of porous concrete to successfully control its target porosity and ideal pore status at different stages is put forward.The related crucial topics includ-ing optimal target porosity,reinforced measures,concrete surface texture optimization,and new mix proportioning design based on target porosity are also discussed.

  17. Performance of Drained and Undrained Flexible Pavement Structures Under Wet Conditions Test Data From Accelerated Pavement Test Section 543-Drained

    OpenAIRE

    Harvey, John; Bejarano, Manuel O.; Ali, Abdikarim; Russo, Mark; Mahama, David; Hung, Dave; Preedonant, Pitipat

    2004-01-01

    This report is the first in a series of four reports that describe the results of accelerated pavement tests on full-scale pavements with “wet†base conditions at the Pavement Research Center, located at the University of California Berkeley Richmond Field Station (RFS). The report contains a summary of the results and associated analysis of a pavement section comprised of three lifts of asphalt concrete, an asphalt treated permeable base (ATPB) layer, and untreated aggregate base layers o...

  18. A Study on Overlay Design of Repeatedly Deteriorating Flexible Pavement

    Directory of Open Access Journals (Sweden)

    Mahendrakar Kiran Kumar

    2015-06-01

    Full Text Available A factor, which causes further concern in India, is very high and very low pavement temperature in some parts of the country. Under these conditions, flexible pavements tend to become soft in summer and brittle in winter. Further increase in road traffic during the last one decade with an unduly low level of maintenance has contributed to accelerated deterioration of road surfacing. To prevent this deterioration process, several types of measures may be adopted effectively such as improved design, use of high performance materials and effective construction technologies. Over the last two decades, traffic volume and the percentage of heavy truck traffic have increased enormously on the National High Way No 18. This pavement is a Flexible pavement with bituminous surfacing. The high traffic intensity in terms of commercial vehicles, overloading of axles and significant variations in daily and seasonal temperature of the pavement have been always responsible for early development of distress symptoms like undulations, rutting, cracking, bleeding, raveling, shoving and potholing of bituminous surfacing.

  19. 材料粘弹性对沥青混凝土钢桥面铺装结构疲劳寿命预估的影响%Influences of Viscoelasticity of Materials on Estimate of Fatigue Life of Pavement Structure of Asphalt Concrete Steel Deck

    Institute of Scientific and Technical Information of China (English)

    任开亮; 黄天贵; 赵国云

    2015-01-01

    为研究材料粘弹性对钢桥面浇注式沥青混凝土铺装结构疲劳寿命预估结果的影响,建立粘弹性有限元模型,分析不同荷载作用次数下铺装结构表面拉应变的变化规律,并基于应变控制的铺装面层混凝土疲劳方程预估铺装的使用寿命。结果表明:由于受材料粘弹性特性影响,随着荷载作用次数增加,钢桥面铺装表面拉应变也随之增大,铺装疲劳寿命降低;荷载作用20000次前变化更为明显,其后则趋于平缓。%In order to research influences of viscoelasticity of materials on estimate of fatigue life of pavement structure of asphalt concrete steel deck,this paper establishes a viscoelasticity finite element model and analyzes change rules of tensile strain on the surface of pavement structure at different action times of load,and estimates the service life of pavement based on strain controlled fatigue equation of surface concrete of pavement.The results show that the tensile strain on the surface of steel deck pavement increases with more action times of load due to influence of viscous and elastic properties,and fatigue life of pavement decreases;the change before 20 000 action times of load is more significant,and then becomes flat.

  20. MODELING PAVEMENT DETERIORATION PROCESSES BY POISSON HIDDEN MARKOV MODELS

    Science.gov (United States)

    Nam, Le Thanh; Kaito, Kiyoyuki; Kobayashi, Kiyoshi; Okizuka, Ryosuke

    In pavement management, it is important to estimate lifecycle cost, which is composed of the expenses for repairing local damages, including potholes, and repairing and rehabilitating the surface and base layers of pavements, including overlays. In this study, a model is produced under the assumption that the deterioration process of pavement is a complex one that includes local damages, which occur frequently, and the deterioration of the surface and base layers of pavement, which progresses slowly. The variation in pavement soundness is expressed by the Markov deterioration model and the Poisson hidden Markov deterioration model, in which the frequency of local damage depends on the distribution of pavement soundness, is formulated. In addition, the authors suggest a model estimation method using the Markov Chain Monte Carlo (MCMC) method, and attempt to demonstrate the applicability of the proposed Poisson hidden Markov deterioration model by studying concrete application cases.

  1. 透水性铺装系统与大气间热水分传输过程实验方法及初期实验研究%Experimental Method and Initial Experimental Research on Permeable Pavement System and Heat Moisture Transmission Procedure in Atmosphere

    Institute of Scientific and Technical Information of China (English)

    李美玲; 刘京; 李彪; 敖靖

    2013-01-01

    城市透水性铺装材料与传统不透水性沥青路面相比具有良好的透水性能,并能随时间缓慢向附近局地大气蒸发散湿,达到改善城市热舒适环境的效果.本文首先针对实际城市交通透水性铺装系统制作了透水性铺装系统实验台,在实验台设计中创新提出了利用气体微压差变化量间接得到透水性铺装系统试样整体蒸发量变化的“差变单元”的实验方法,并利用此实验台在室外进行了典型透水性铺装系统与传统不透水性铺装系统内部各层热水分传输过程的对比实验,以研究和分析孔隙率大小对透水性铺装系统热水分传输效果的影响,进而归纳城市透水性沥青混凝土铺装系统对改善局地大气环境及地下水循环的优越性.%Compared with traditional impermeable bituminous pavement,urban permeable pavement materials have good permeability performances and can diffuse moisture through slow evaporation to nearby atmosphere,thus achieving the effect of improving thermal comfort environment in cities.In this paper,a test rig for permeable pavement system of urban transport was established,and an experimental method was innovatively brought forward that get indirectly "differential unit" of overall evaporation capacity variation of permeable pavement system samples through micro differential pressure variation of air during the design of test rig.And then,outdoor contrast experiments were carried out for heat moisture transmission procedure at respective layers inside typical permeable pavement system and traditional impermeable pavement system,so as to study and analyze the effect of porosity on heat moisture transmitting in permeable pavement system.Finally,the advantages of urban permeable bituminous concrete pavement system for improving partial atmosphere environment and underground water circulation were concluded.

  2. 纤维沥青混合料的拌和成型工艺研究%Research on Mixing and Shaping Technology of Fiber Bituminous Mixture

    Institute of Scientific and Technical Information of China (English)

    程英伟; 何晓鸣

    2012-01-01

    利用正交试验对剑麻纤维沥青混凝土混合料的拌和成型工艺进行研究.在固定配合比的前题下,以拌和方案、沥青加热温度、集料加热温度和成型温度为试验因素,模拟路面施工的各种拌和成型情况设计了L9正交表分别进行马歇尔试验.运用极差分析法对试验结果进行分析,确定了纤维沥青混合料拌和成型的优选方案为“同步法拌和+沥青加热温度为175℃+集料加热温度为206℃+成型温度为165℃”.最后分析了几种试验因素对试验指标的影响机理.%In this paper, mixing and shaping technology of bituminous concrete mixture with sisal fiber is researched by orthogonal experiment. Under a fixed mix proportion, mixing solutions, asphalt heating temperature, aggregate heating temperature and shaping temperature are selected as test factors. The variety of mixing and shaping in pavement construction is simulated by designing a L9 orthogonal table for Marshall tests. Range Analysis Method is used to analyze test results, and then the optimal scheme of mixing and shaping for fiber bituminous concrete mixture is determined. The optimal scheme is "synchronization method of mixing+asphalt heating temperature of 175℃+aggregate heating temperature of 206℃ + shaping temperature of 165℃”. Last, the influence mechanism of test factors on test indicators is analyzed.

  3. The Construction Technology and Quality Control of Hot Mix Asphalt Concrete Pavement%热拌沥青混凝土路面施工工艺及质量控制

    Institute of Scientific and Technical Information of China (English)

    卢宪法

    2014-01-01

    热拌沥青混凝土作为公路路面施工的重要组成部分,其选材、施工工艺、质量控制等流程对公路的建成性能都具有决定性的影响。笔者结合近年来的学习工作经验,主要从材料、沥青混凝土的配比、施工工艺、质量控制几个方面作简要阐述。%Hot mix asphalt concrete as an important part of highway pavement construction, the material selection, constr-uction technology and quality control hasa decisive influence on the process of highway completed performance. The author combines with work experience in recent years to elaborate from several aspects of material, the ratio of asphalt concrete, construction technology, and quality control, etc.

  4. 钢管混凝土拱桥桥面铺装动力学特性研究%Research on Dynamics Characteristics of Deck Pavement of Concrete-Filled Steel Tube Arch Bridge

    Institute of Scientific and Technical Information of China (English)

    杨咏梅; 庄月明

    2011-01-01

    首先,建立了千岛湖钢管混凝土拱桥的3D有限元模型.通过有限元计算,得到了该钢管混凝土拱桥前8阶的自振频率和自振振型.同时,计算了该钢管混凝土拱桥的水平自振基频与竖向自振基频.接着,选用移动恒载研究车辆荷载作用下的钢管混凝土拱桥桥面铺装结构动力学特性.计算得到该钢管混凝土拱桥的共振速度并分析了桥梁共振响应的可能性.计算了不同车速下跨中节点的竖向最大位移与纵向拉应力,并进一步计算了冲击系数,提出了钢管混凝土拱桥的荷载冲击系数参考值.最后,考虑施工荷载,计算了梁底最大拉应力与最大剪应力,分析了Dynapac CC522型振动压路机施工时对桥梁结构的影响.%First of all, finite element 3D model of the concrete-filled steel tube arch bridge above Qian-dao Lake is established. By calculation of finite element method, the initial eight stages auto-oscillation frequency and mode of the concrete-filled steel tube arch bridge are acquired. Meanwhile, horizontal and vertical auto-oscillation fundamental frequency of the concrete-filled steel tube arch bridge is calculated. Secondly, moving constant load is used to research the dynamics characteristics of deck pavement of the concrete-filled steel tube arch bridge. Resonance velocity of the concrete-filled steel tube arch bridge above Qiandao Lake is computed to analyze the probability of bridge resonance. The maximum vertical displacement and longitudinal tensile stress of mid-span node under different vehicle speeds are calculated. Furthermore, impact coefficient reference value of the concrete-filled steel tube arch bridge is put forward. Finally, considering construction loads, the maximum tensile stress and shearing stress of beam bottom are calculated to analyze the influence of construction exploiting "Dynapac CC522" vibratory roller.

  5. 脱空状态下水泥混凝土路面最大弯拉应力及疲劳寿命的响应分析%Maximum Stretch Stress and Fatigue Life Response Analysis of Concrete Pavement with Void under Slab

    Institute of Scientific and Technical Information of China (English)

    阳宏毅

    2011-01-01

    通过采用有限元分析软件ANSYS建模,计算水泥混凝土路面在脱空状态下的最大弯拉应力,并考虑板块厚度、脱空深度、脱空范围等因素对水泥混凝土路面的最大弯拉应力的力学响应,结合计算结果分析脱空状态对水泥混凝土路面疲劳寿命影响.%An ANSYS model is adopted to calculate the maximum stretch stress of concrete pavement with void under slab considering the effect of slab thickness, void depth and area under slab, the result is used to analyse the fatigue life of concrete pavement with void under slab.

  6. Evaluation of Asphalt Concrete Pavement Based on Passenger Ride Comfort Level%基于驾乘舒适性的沥青混凝土路面评价

    Institute of Scientific and Technical Information of China (English)

    王锋; 张金喜

    2014-01-01

    In order to provide a theoretical basis for the ride comfort level evaluation, daily management,and maintenance of asphalt concrete pavement,the performance parameters and three-directional acceleration data of highway pavements were measured indoors and outdoors. Using these data,the relationship between the mean square of weighted acceleration and the pavement performance was studied. A linear regression equation that reflects the relationship between the root mean square of weighed acceleration,speed,and roughness was obtained by fitting 214 groups of experimental data. In addition,the outdoor experimental results were verified using a driving simulator. The results show that the root mean square of weighed acceleration is strongly correlated with roughness,moderately correlated with the speed,and weakly correlated with the dynamic friction coefficient. Given a certain dynamic friction coefficient,the ride comfort level of an asphalt concrete pavement reduces with its roughness and driving speed increasing. When the roughness is 1. 35 and 3. 05 mm/m,the maximum speed with an appropriate ride comfort level is 124. 1 and 88. 7 km/h,respectively.%为给沥青混凝土路面舒适性评价及日常管理养护提供理论依据,在测得室内外大量道路路面性能参数及三向加速度数据的基础上,研究了加权加速度均方根值与道路路面性能参数之间的关系.运用214组有效室外实验数据,拟合了加权加速度均方根、行驶速度与平整度关系的线性回归方程,并用驾驶模拟舱对室外实验结论进行了验证.结果表明:加权加速度均方根与平整度强相关,与速度中等程度相关,与动态摩擦系数弱相关,在动态摩擦系数一定的条件下,驾乘舒适性随平整度及行驶速度的增加而降低;当平整度为1.35和3.05 mm/m时,满足驾乘舒适性的最大速度分别为124.1和88.7 km/h.

  7. 地聚合物水泥路面快速修补材料性能研究%Study on the Properties of Geopolymer Concrete Using as Rapid Repair Materials for Cement Pavement

    Institute of Scientific and Technical Information of China (English)

    常利; 艾涛; 延西利; 吕霖; 杨慧成

    2014-01-01

    针对水泥路面修补后开放交通时间偏长、耐久性较差和施工工艺复杂的问题,采用固体复合激发剂、粉煤灰和偏高岭土及其他外加剂制备一种地聚合物水泥快速修补材料,并对其混凝土力学性能、界面粘结性能、收缩率、抗冻性能进行测试.结果表明,当掺入10%的复合激发剂和10%的普通硅酸盐水泥时,地聚合物水泥的早期力学性能达到最优,所制备的地聚合物水泥混凝土修补材料具有快凝早强和优良的耐久性等特点,扫描电子显微镜(SEM)微观分析表明,由于碱激发反应和未激发粉煤灰的填充效应,地聚合物水泥混凝土具有致密的微观结构.%In order to solve long opening-to-traffic time,poor durability and complex process of concrete pavement repaired problem,a kind of rapid repair geopolymer material was prepared using the solid composite activator,fly ash,metakaolin and other admixtures.The properties of the working performance,mechanical properties,bonding performance between New and old Concrete,shrinkage,frost resistance of geopolymer-cement-concrete were tested.The experimental results show that with 10% compound activators and 10% ordinary Portland cement,the early mechanical properties of the geopolymer cement can achieve the optimal; the rapid repair geopolymer-cement-concrete has the advantages of quick setting early strength and excellent durability.The scanning electron microscopy (SEM) results indicatethat the geopolymer-cement-concrete has micro compact structure as the result of the filling effect of inactivated fly ash and alkali activated reaction.

  8. 旧水泥混凝土路面加铺水泥-泡沫沥青半柔性混合料的力学响应分析%Analysis of mechanical response of semi-flexible mixture material of cement-foam asphalt overlayed on old concrete pavement

    Institute of Scientific and Technical Information of China (English)

    李秀君; 李梦晨; 武昭融

    2013-01-01

    Aimed at the problem that old concrete pavement overlayed with asphalt surface is prone to reflective cracking,the paper proposed that the old concrete pavement overlayed with the semi-flexible mixture of cement-foam asphalt should significantly reduce the possibility of surface cracking.In order to guide pavement structure design,the paper studied the mechanical performance of the old concrete pavement by using ANSYS finite-element method,and got the conclusion that the method would significantly reduce the tensile stress and maximum shearing stress in asphalt layer and relieve the cracking of the asphalt pavement.In addition,it would reduce the sensitivity of asphalt surface crack width of the old cement board.The thickness of semi-flexible mixture material paved on the old concrete pavement should not less than 8cm.%针对旧水泥路面加铺沥青面层易出现反射裂缝问题,本文提出在旧水泥混凝土路面上铺筑水泥-泡沫沥青半柔性混合料再铺筑沥青面层,可显著降低面层开裂的可能性.为合理指导路面结构设计,论文采用ANSYS有限元软件进行路面结构力学计算,研究水泥-泡沫沥青半柔性混合料对路面结构力学的响应.研究得出旧水泥板上加铺水泥-泡沫沥青半柔性材料,可显著减弱沥青面层层底拉应力及层内最大剪应力,可有效缓解沥青层的反射裂缝的出现,同时还可以显著降低沥青面层对旧水泥板裂缝宽度的敏感性.在旧水泥混凝土板上加铺水泥-泡沫沥青半柔性混合料,其厚度不宜低于8 cm.

  9. 混凝土桥面双层SMA铺装高温性能研究%Research on High-temperature Performance of Double-layer SMA Pavement on Concrete Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    杨通明

    2014-01-01

    At present the asphalt layer paved on cement concrete bridge deck adopts the same structure as the general pavement. In accordance with foreign applications, this paper lays down 5 double-layer SMA structures in different combination modes and inspects the high -temperature resistant deformation performance of each type of mixtures via Schellenberg Binder Drain Down Test, Cantabro Test and rutting test. On this basis the paper analyzes the high-temperature resistant deformation performance of double-layer SMA structures in 5 different combination modes via APA test and rutting test, the results show that the integral capability of double-layer SMA structures resistant to deformation is mostly dependent on combination modes of structures; the integral deformation resistant capability of combination between the mixture on upper surface course with less strong deformation resistant capability and the mixture on lower surface course with strong deformation resistant capability may be superior to the combination of double-layer mixtures with strong deformation resistant capability; therefore, the combination of pavement layer structures of SMA13+SMA9. 5 or SMA9. 5+SMA13 are recommended for concrete bridge deck.%当前水泥混凝土桥面铺装沥青层一般采用与路面相同的结构。根据国外应用情况,拟定不同组合方式的5种双层SMA结构,通过谢伦堡析漏试验、肯塔堡飞散试验以及车辙试验来检验每种类型混合料的抗高温变形性能。在此基础上,通过APA试验和车辙试验分析5种不同组合方式的双层SMA结构抗高温变形性能,结果显示:双层SMA结构整体抗变形能力更大程度上依赖于结构组合方式;上面层抗变形能力稍差的混合料与下面层抗变形能力较强的混合料组合的整体抗变形能力可能优于双层抗变形能力较强的混合料组合;故推荐混凝土桥面采用SMA13+SMA9.5或SMA9.5+SMA13铺装层结构组合。

  10. Discussion of the method of reworking an old cement concrete pavement by superimposing a new one%对“白加白”改造旧水泥砼路面实施方案的探讨

    Institute of Scientific and Technical Information of China (English)

    何勇兵

    2011-01-01

    G318怀宁段路面改善工程设计方案为旧水泥砼路面加铺水泥砼路面(简称"白加白"),在安庆市公路系统尚属首次实施,在我省亦无成功的实践经验可直接借鉴。为此,安庆市公路局专门成立了科研小组,并与浙江大学合作,以"白加白改造旧水泥砼路面方案的研究"为课题,将G318怀宁段作为实践项目,申报2010年度安徽省交通科技项目。笔者作为小组三位主要成员之一,全过程参与该项目的建设与管理。现就该方案的实践成果进行一次全面系统的总结,并就有关技术问题进行探讨。%Superimposing a new cement concrete pavement on the old one is designed to improve the Huaining segment of Highway G318.This is the first practice of this kind in Anqing,without successful experiences in the province that can be directly used for reference.For this,Anqing Municipal Administration specially formed a scientific research group,which,jointly with Zhejiang Univesity,applied for a sci-tech project in 2010 titled Study on the Viability of Reworking Old Cement Concrete Pavement by Superimposing A New One with the Huaining segment of highway G318 as a practice.The author,as one of the three key members of the group,participated in the project construction and management in overall process,summarized the work results and discussed some technical issues in this paper.

  11. Pavement Subgrade Performance Study

    DEFF Research Database (Denmark)

    Zhang, Wei; Ullidtz, Per; Macdonald, Robin

    1998-01-01

    The report describes the second test in the Danish Road Testing Machine (RTM) under the International Pavement Subgrade Performance Study. Pavement response was measured in different layers, and compared to different theroretical values. Performance in terms of plastic strains, rutting...

  12. Permeable pavement study (Edison)

    Data.gov (United States)

    U.S. Environmental Protection Agency — While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types...

  13. Evaluation for Subgrade Permanent Deformation of Cement Concrete Pavement%水泥混凝土路面路基永久变形预估

    Institute of Scientific and Technical Information of China (English)

    谭悦

    2012-01-01

    Using the model of evaluation for subgrade permanent deformation and layerwise strain summation method, in considering the clay, silt and sand, the permanent deformations of subgrade are calculated with the load action on edge of board, center of board, and angle of board. Calculation shows that, for certain pavement structure and traffic axle load, permanent deformation of the clay subgrade is the largest, and the sand subgrade is the minimum; for the same soil, subgrade permanent deformation is the largest or minimum when angle of board loaded or center of board loaded; when edge of board loaded, the board's size smaller, the subgrade permanent deformation greater; subgrade permanent deformation caused by angle of board loaded is the most adverse condition for the pavement s force status.%结合修正后的路基永久变形预估模型和应变分层总和法,在考虑粘土、粉土和砂土3种不同土质状态下,分别预估了荷载作用于板边、板中及板角时路基产生的永久变形.计算表明,对于一定的路面结构和交通轴载,粘土路基的永久变形量最大,粉土次之,砂土最小;对于同一种土质,板角受荷时路基的永久变形最大,板边受荷次之,板中受荷最小;当荷载作用在板边时,板的尺寸越小,路基的永久变形越大;板角受荷造成的路基永久变形对水泥路面的受力状况是最为不利的.

  14. Stress Analysis and Determination of Effective k-value for Rigid Pavement

    OpenAIRE

    Kundan Meshram; H.S. Goliya; Akhilesh Poddar

    2013-01-01

    EverFE is a user-friendly 3D finite-element analysis tool for simulating the response of jointed plain concrete pavement (JPCP) systems to axle loads and environmental effects. EverFE is useful for both concrete pavement researchers and designers who must perform either complex nonlinear or simple linear stress analyses of JPCP.With help of this develop any type of model of rigid pavement considering practical condition thus getting more accurate and advance analysis for rigid pavement. It ca...

  15. Vehicle-Pavement Interaction

    OpenAIRE

    Khavassefat, Parisa

    2014-01-01

    Several aspects of vehicle-pavement interaction have been studied and discussed in this thesis. Initially the pavement response is studied through a quasi-static and a dynamic computationally efficient framework under moving traffic loads. Subsequently, a non-stationary stochastic solution has been developed in order to account for the effect of pavement surface deterioration on pavement service life.The quasi-static procedure is based on a superposition principle and is computationally favou...

  16. Nitrogen Transformations in Three Types of Permeable Pavement

    Science.gov (United States)

    In 2009, USEPA constructed a 0.4-ha (1-ac) parking lot at the Edison Environmental Center in Edison, NJ, that incorporated three different permeable pavement types - permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). The driving lanes...

  17. Hybrid green permeable pave with hexagonal modular pavement systems

    Science.gov (United States)

    Rashid, M. A.; Abustan, I.; Hamzah, M. O.

    2013-06-01

    Modular permeable pavements are alternatives to the traditional impervious asphalt and concrete pavements. Pervious pore spaces in the surface allow for water to infiltrate into the pavement during rainfall events. As of their ability to allow water to quickly infiltrate through the surface, modular permeable pavements allow for reductions in runoff quantity and peak runoff rates. Even in areas where the underlying soil is not ideal for modular permeable pavements, the installation of under drains has still been shown to reflect these reductions. Modular permeable pavements have been regarded as an effective tool in helping with stormwater control. It also affects the water quality of stormwater runoff. Places using modular permeable pavement has been shown to cause a significant decrease in several heavy metal concentrations as well as suspended solids. Removal rates are dependent upon the material used for the pavers and sub-base material, as well as the surface void space. Most heavy metals are captured in the top layers of the void space fill media. Permeable pavements are now considered an effective BMP for reducing stormwater runoff volume and peak flow. This study examines the extent to which such combined pavement systems are capable of handling load from the vehicles. Experimental investigation were undertaken to quantify the compressive characteristics of the modular. Results shows impressive results of achieving high safety factor for daily life vehicles.

  18. Water quality and quantity assessment of pervious pavements performance in experimental car park areas

    OpenAIRE

    Sañudo Fontaneda, Luis Ángel; Charlesworth, Susanne M.; Castro Fresno, Daniel; Andrés Valeri, Valero Carlos Alessio; Rodríguez Hernández, Jorge

    2014-01-01

    Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates a...

  19. Brief Analysis on the Key Factors of Raw Materials Influencing the Mix Strength of Cement Concrete Pavement%浅析原材料影响水泥混凝土路面配合比强度的关键因素

    Institute of Scientific and Technical Information of China (English)

    林泽彬

    2011-01-01

    水泥混凝土路面配合比设计阶段是保证路面实体强度的首要阶段,也是十分重要的阶段。笔者依据多年的经验并结合多条高速公路的施工监理实践,在广梧高速公路河口至平台B段的施工监理过程中,针对水泥混凝土路面配合比设计阶段,从原材料各个主要因素入手对配合比进行单因素优化设计,找出原材料影响水泥混凝土强度(主要是抗折强度)的关键因素,为现场配合比设计的质量控制提供一定的借鉴经验。%Mix Design of cement concrete pavement is not only the first stage to guarantee the strength of pavement,but also the most important stage.Based on years of experience and supervision practice for several expressway construction projects,particularly the construction supervision of B segment between Hekou and Pingtai of Guangzhou-Wuzhou Expressway,in the light of the mix design of cement concrete pavement stage,optimized mix design base on each major factor of raw materials has been carried out to find out the key factors of raw materials which will influence cement concrete strength(mainly flexural strength),which can provide references for the future on-site quality control of cement concrete mix design.

  20. 彩色透水混凝土路面工程管理实践%Color Pervious Concrete Pavement Project Management Practices

    Institute of Scientific and Technical Information of China (English)

    马健萍

    2011-01-01

    以生物岛环岛路观光车道的彩色透水混凝土道路工程为例,介绍了彩色混凝土的材料及施工要点,并从施工前检查、施工放样检查及基坑检查等监理工作要点进行阐述,为类似工程提供参考和借鉴。%Bio -Island tour- lane road around the island color permeable concrete road projects, for instance, describes the color of concrete materials and construction elements, and from the pre - construction inspection, construction layout, inspection and supervision work of excavation inspection points were set for similar project to provide reference and learning.

  1. Application of surplus and waste materials in roads pavement making

    OpenAIRE

    S.M. Mousavi; Fazli, A. H.; Rouzmehr, F.

    2011-01-01

    Nowadays there are a lot of problems about surpluses and debris made by humans all around the world. Lots of these surpluses seriously harm our natural environment. Reuse of this kind of materials in other processes like building constructions or pavement help our natural environment in every aspect. Asphalt concrete is the main part of pavements in most parts of the world with an increasing rate of production in need of more ways and roads. In this paper we will provide...

  2. Application of Energy Efficient Warm Mix Asphalt Concrete in Pavement Construction in Extremely Cold Areas%低能耗温拌沥青混凝土施工技术在高寒地区路面工程中的应用

    Institute of Scientific and Technical Information of China (English)

    唐忠平; 宋远慧

    2011-01-01

    温拌温铺沥青混凝土初次在青藏高原公路施工技术上的尝试和应用,克服了低温作业的影响,有效降低有害气体和粉尘颗粒排放,同时又保证了与热拌沥青混凝土基本相同的路用性能和施工和易性,为工程顺利实施赢得时间效益。%The first application of warm mix asphalt concrete in highway construction in Qinghai-Tibet Plateau overcame the impact of low temperature,reduced harmful gas and dust particles effectively and at the same time ensured the same pavement performance and construction workability with that of hot mix asphalt,which gained time efficiency for successful implementation of pavement engineering.

  3. Use of scrap rubber in asphalt pavement surfaces

    Science.gov (United States)

    Eaton, Robert A.; Roberts, Richard J.; Blackburn, Robert R.

    1991-12-01

    Scrap tire rubber was mixed into an asphalt concrete wearing course to study the effect of ice disbonding from the pavement surface under traffic. Rubber contents of 0, 3, 6, and 12 percent by weight were studied. Initial laboratory ice disbonding test results led to the development of a new paving material, Chunk Rubber Asphalt Concrete (CRAC), that uses larger pieces of rubber in a much denser asphalt concrete mix. Strength values doubled and ice disbonding performance was enhanced.

  4. Noise Reduction Properties of an Experimental Bituminous Slurry with Crumb Rubber Incorporated by the Dry Process

    Directory of Open Access Journals (Sweden)

    Moisés Bueno

    2014-08-01

    Full Text Available Nowadays, cold technology for asphalt pavement in the field of road construction is considered as an alternative solution to conventional procedures from both an economic and environmental point of view. Among these techniques, bituminous slurry surfacing is obtaining an important role due to the properties of the obtained wearing course. The functional performance of this type of surfaces is directly related to its rough texture. Nevertheless, this parameter has a significant influence on the tire/road noise generation. To reduce this undesirable effect on the sound performance, new designs of elastic bituminous slurries have been developed. Within the FENIX project, this work presents the acoustical characterization of an experimental bituminous slurry with crumb rubber from wasted automobile tires incorporated by the dry process. The obtained results show that, under controlled operational parameters, the close proximity sound levels associated to the experimental slurry are considerably lower than those emitted by a conventional slurry wearing course. However, after one year of supporting traffic loads and different weather conditions, the evaluated bituminous slurry, although it conserves the original noise reduction properties in relation to the conventional one, noticeably increases the generated sound emission. Therefore, it is required to continue improving the design of experimental surfaces in order to enhance its long-term performance.

  5. 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. PMID:20566237

  6. 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.

  7. 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…

  8. COMPARISON OF PAVEMENT STRUCTURES IN TUNNELS

    OpenAIRE

    Rimac, Ivan; Šimun, Miroslav; Dimter, Sanja

    2014-01-01

    Tunnels pose many fire risks. It is difficult to fight fires in tunnels due to their limited accessibility, the quantity of smoke, and high thermal radiation. Temperatures in tunnel fires can reach 1000 °C, and these fires can spread quickly and persist for long periods, the longest recorded in Europe lasting 53 h. The main requirements of tunnel pavement structures are driving safety and comfort, as well as low construction and maintenance costs. Choosing between using concrete or asphalt pa...

  9. Pavement Testing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Comprehensive Environmental and Structural Analyses The ERDC Pavement Testing Facility, located on the ERDC Vicksburg campus, was originally constructed to provide...

  10. 机场道面除冰液作用下大掺量粉煤灰混凝土的抗冻性%Freeze-thaw Durability of High Volume Fly Ash Content Concrete Exposed to Airfield Pavement Deicer

    Institute of Scientific and Technical Information of China (English)

    麻海燕; 吴雅玲; 余红发; 白康; 袁银峰

    2014-01-01

    The freeze-thaw durability of high volume fly ash content concrete (HFCC)specimens were tested by fast freezing-thawing experiments.In the experiments,HFCC specimens exposed to different solutions which were composed of airfield pavement deicer,NaCl solution,aircraft deicer (AD),commercial deicer and water.The airfield pavement deicer mainly contained calcium magnesium acetate (CMA)and was changed at mass fractions of 3.5%,12.5% and 25%.The mass fractions of NaCl solution,aircraft deicer and commercial deicer were 3 .5%,3 .5% and 25%,respectively.Through the experiments,the change rules of the mass loss rate per unit area and the relative dynamic elastic modulus of HFCC were obtained.The results show that freeze-thaw damage of HFCC exposed to 3 .5% NaCl solution is closely attributed to surface deterioration.When HFCC specimens exposed to 3 .5% AD or 3 .5% CMA solution,it will be damaged by internal freeze-thaw damage.Compared with water,freeze-thaw damage effect of HFCC is delayed by 3 .5% CMA solution.Freeze-thaw durability of concrete exposed to CMA solutions is closely related to the solution mass fractions,the higher the CMA mass fraction is,the smaller the freeze-thaw damage effects are.When the CMA mass fraction is greater than 12.5%, the mass loss rate and the relative dynamic elastic modulus losses are small after 600 times fast freeze-thaw cycle.HFCC has a poor freeze-thaw durability when exposed to 25% commercial deicer and has a good freeze-thaw durability when exposed to 25% airfield pavement deicer. Therefore,HFCC can be completely applied to the cement concrete airfield runway which is deiced by high mass fractions of CMA.%通过大掺量粉煤灰混凝土(HFCC)试件在质量分数为3.5%,12.5%,25%机场道面除冰液(CMA溶液)、质量分数为3.5%的NaCl溶液、质量分数为3.5%的飞机除冰液(AD溶液)、质量分数为25%的商品飞机除冰液与水中快速冻融试验

  11. Fatigue performance and equations of roller compacted concrete with fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Sun, W.; Liu, J.; Qin, H.; Zhang, Y. [Southeast Univ., Nanjing (China); Jin, Z.; Qian, M. [Highway Bureau of Jiangsu Province (China). Communication Dept.

    1998-02-01

    In this paper, the influence of fly ash on the fatigue performance of roller compacted concrete was studied. The fatigue equations of roller compacted concrete without and with fly ash, which can be used for designing pavement, are proposed through the method of the regressive analysis, and compared with that of the same grade common concrete pavement.

  12. 9 CFR 91.26 - Concrete flooring.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Concrete flooring. 91.26 Section 91.26... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.26 Concrete flooring. (a) Pens aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000...

  13. FORMULATION AND APPLICATION OF FATIGUE EQUATION FOR POROUS CEMENT CONCRETE%多孔水泥基混凝土疲劳方程的建立及应用

    Institute of Scientific and Technical Information of China (English)

    陈拴发; 郑木莲; 王秉纲

    2005-01-01

    作为水泥混凝土或沥青路面基层的多孔混凝土和面层一起受到荷载和温度的反复作用,因此,在路面应力分析和结构设计中需考虑它的疲劳性能.在多孔混凝土小梁弯拉疲劳实验的基础上,通过分析疲劳寿命实验数据的概率分布,得出其疲劳寿命服从双参数Weibull分布,并依次回归出不同应力水平和等效应力水平下两种形式的疲劳方程.根据疲劳方程提出了以多孔混凝土作为水泥混凝土路面下面层应力计算的荷载疲劳应力系数,沥青路面基层层底拉应力验算的抗拉强度结构系数,建立了进行路面结构设计的轴载换算模型.%Porous concrete, serving as the base of a cement concrete or a bituminous pavement, should withstand the repeated actions of traffic and temperature together with the road surface. Therefore, the fatigue characteristic was considered in pavement stress analysis and structure design. Based on indoor flexural tensile fatigue tests of small beams, through analyzing the probability distribution of the fatigue life, it was proved that the fatigue life of the porous concrete obeys two-parameter Weibull distribution, and two types of fatigue equations were formulated under different stress level and equivalent stress level. The load fatigue stress coefficient used in the load stress calculation for the porous concrete as undersurface of the cement concrete pavement were derived. The tensile strength structure coefficient used in the tensile stress check for the porous concrete as the base of an asphalt pavement, and the axle load conversion model used in pavement structure design was put forward.

  14. Layered pavement systems

    Science.gov (United States)

    Numerous aspects of the mechanical and structural response of layered pavement systems are discussed. Subgrade moduli for soil that exhibits nonlinear behavior are predicted. The use of a pressure meter test to predict modulus is discussed. Load equivalency factors of triaxial loading for flexible pavements is discussed, as well as a constitutive equation for the permanent strain of sand subjected to cyclic loading.

  15. 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…

  16. Evaluation of accelerated deterioration in NAPTF flexible test pavements

    Institute of Scientific and Technical Information of China (English)

    Kasthurirangan GOPALAKRISHNAN

    2008-01-01

    Previous research studies have successfully demonstrated the use of artificial neural network(ANN)models for predicting critical structural responses and layer moduli of highway flexible pavements.The primary objective of this study was to develop an ANN-based approach for backcalculation of pavement moduli based on heavy weight deflectometer(HWD)test data,especially in the analysis of airport flexible pavements subjected to new generation aircraft(NGA).Two medium-strength subgrade flexible test sections,at the National Airport Pavement Test Facility(NAPTF),were modeled using a finite element(FE) based pavement analysis program,which can consider the non-linear stress-dependent behavior of pavement geomaterials.A multi-layer,feed-forward network which uses an error-backpropagation algorithm was trained to approximate the HWD backcalculation function using the FE program generated synthetic database.At the NAPTF,test sections were subjected to Boeing 777 (B777)trafficking on one lane and Boeing 747(B747)trafficking on the other lane using a test machine.To monitor the effect of traffic and climatic variations on pavement structural responses.HWD tests were conducted on the traffieked lanes and on the untraffieked centerline of test sections as trafficking progressed.The trained ANN models were successfully applied on the actual HWD test data acquired at the NAPTF to predict the asphalt concrete moduli and non-1inear subgrade moduli of the medium-strength subgrade flexible test sections.

  17. 广肇高速公路水泥路面加铺沥青砼方案分析%Scheme Analysis on Asphalt Concrete Covering Cement Pavement of Guangzhao Expressway

    Institute of Scientific and Technical Information of China (English)

    谢永明

    2014-01-01

    广肇高速公路水泥路面长度为10km,结合实际交通荷载情况、路面受力状况、加铺后养护成本降低及养护便利性等方面分析了广肇高速公路水泥路面加铺的必要性,结合省内相关加铺项目的经验,通过加铺层结构计算,提出了广肇高速公路水泥路面加铺的可行方案,可供相关项目管理单位参考。%The length of cement pavement of Guangzhao Expressway is 10Km.According to the actual traffic load,stress condition of the pavement,cost reduction and convenience of maintenance after pavement overla-ying,the necessity of overlaying for cement pavement has been analyzed.Combined with experiences from other cement pavement overlaying projects,through the overlay structure calculation,a feasible scheme of overlaying for cement pavement of Guangzhao Expressway has been put forward,which could provide references for relative project management units.

  18. Effect of Airfield Pavement Deicer on Freeze-thaw Durability of High Performance Concrete%机场道面除冰液对高性能 混凝土抗冻性的影响

    Institute of Scientific and Technical Information of China (English)

    麻海燕; 余红发; 白康; 曹文涛; 周鹏; 韩丽娟

    2011-01-01

    Influence of calcium magnesium acetate (CMA) , which is the main composition of the most frequently used as airfield pavement dicer, on the freezing-thaw durability of high performance concrete (HPC ) were investigated. Freeze-thaw durability of HPC was tested by accelerated freezing-thawing test. Five kinds of solutions, namely tap water, 3.5%NaCl solution, 3.5%-25% calcium magnesium acetate (CMA), 25% glycol solution and commercial aircraft deicer were employed to be the freeze-thaw mediums. Results show that freeze-thaw durability of HPC exposed to CMA solutions is related to the solution concentrations. CMA solution with a concentration of 3. 5% is beneficial to durability of HPC. Freeze-thaw failure of concrete exposed to 3. 5% CMA solution is 1. 09 of that of HPC exposed to tap water; both are resulted from propagation of inner cracks. While freeze-thaw failure of HPC exposed toNaCl solution is different and characterized by surface deterioration. 25% CM A solution shows no damage to HPC'freeze-thaw durability, while both 25% glycol solution and commercial aircraft deicer demonstrate obviously damage to HPC'freeze-thaw durability. The results showed that CMA can effectively improve the freeze-thaw durability of HPC.%采用快冻法测定了高性能混凝土(High Performance Concrete,HPC)在水、浓度为3.5%的NaCl除冰盐、3.5%~25%的醋酸钙镁(Calcium magnesium acetate,CMA,机场道面除冰液)、25%的乙二醇(飞机除冰液)和商品飞机除冰液中的抗冻性.结果表明,在3.5% CMA溶液中,HPC抗冻性比水中冻融提高了1.09倍,其冻融破坏特征与水中冻融一样,均属于内部微裂纹扩展,完全不同于HPC在3.5% NaCl溶液中的盐冻表面剥蚀.在浓度为25%的条件下,CMA机场道面除冰液对HPC无冻融破坏作用,而乙二醇飞机除冰液、尤其是商品飞机除冰液对HPC有明显的冻融破坏作用.因此,CMA机场道面除冰液能够有效地延缓HPC的冻融破坏.

  19. Resonance Testing of Asphalt Concrete

    OpenAIRE

    Gudmarsson, Anders

    2014-01-01

    This thesis present novel non-destructive laboratory test methods to characterize asphalt concrete. The testing is based on frequency response measurements of specimens where resonance frequencies play a key role to derive material properties such as the complex modulus and complex Poisson’s ratio. These material properties are directly related to pavement quality and used in thickness design of pavements. Since conventional cyclic loading is expensive, time consuming and complicated to perfo...

  20. Study on Concrete Pavement Materials Using Fluidized Bed Combustion Coal Ashes%燃煤固硫灰渣混凝土路面材料研究

    Institute of Scientific and Technical Information of China (English)

    黄煜镔; 钱觉时; 张建业; 党玉栋

    2011-01-01

    Using local industrial solid waste to reduce the building cost of rural road is very important. With the experimental study on cementitious system mixed with fluidized bed combustion coal ashes, the results show that; fluidized bed combustion coal ashes have a significant pozzolanic activity due to the characteristic of porous surface and low degree of anionic polymerization, and these ashes can be organized a cementitious systems with alkali and sulfate activator,in which the fluidized bed combustion coal ashes could be up to 70%. Mixing cement and increasing the amount of sulfate-activating agent can improve the early performance of the system significantly. Especially,the dosage of sodium sulfate must be more than 1. 5%. The properties of concrete mixed with fluidized bed combustion coal ashes are suitable in terms of strength and brittleness which make it be used in the rural road successfully.%降低农村公路造价具有重要的现实意义,利用地方工业固体废弃物是一种途径.通过对燃煤固硫灰渣胶凝系统的试验研究,结果表明:燃煤固硫灰渣表面疏松和阴离子聚合度低的特征,使其具有显著的火山灰效应,可与碱、硫酸盐激发剂组成胶凝系统,其中固硫灰渣占70%以上;掺加水泥和增大硫酸盐激发剂掺量能显著改善系统早期性能,硫酸盐掺量宜大于1.5%;燃煤固硫灰渣混凝土具有较好的强度性能和材料韧性,在农村公路中应用具有现实可行性.

  1. Stress Analysis and Determination of Effective k-value for Rigid Pavement

    Directory of Open Access Journals (Sweden)

    Kundan Meshram

    2013-03-01

    Full Text Available EverFE is a user-friendly 3D finite-element analysis tool for simulating the response of jointed plain concrete pavement (JPCP systems to axle loads and environmental effects. EverFE is useful for both concrete pavement researchers and designers who must perform either complex nonlinear or simple linear stress analyses of JPCP.With help of this develop any type of model of rigid pavement considering practical condition thus getting more accurate and advance analysis for rigid pavement. It can also determine effective k-values for different combination of granular sub-base and dry lean concrete. A comparative study is done for two types of loading i.e. single and tandem axle. Edge and Corner stresses are also calculated for Class-AA of loading. Also calculate moment and shear force transfer by dowel bar by EverFE.

  2. Stormwater quality of spring-summer-fall effluent from three partial-infiltration permeable pavement systems and conventional asphalt pavement.

    Science.gov (United States)

    Drake, Jennifer; Bradford, Andrea; Van Seters, Tim

    2014-06-15

    This study examined the spring, summer and fall water quality performance of three partial-infiltration permeable pavement (PP) systems and a conventional asphalt pavement in Ontario. The study, conducted between 2010 and 2012, compared the water quality of effluent from two Interlocking Permeable Concrete Pavements (AquaPave(®) and Eco-Optiloc(®)) and a Hydromedia(®) Pervious Concrete pavement with runoff from an Asphalt control pavement. The usage of permeable pavements can mitigate the impact of urbanization on receiving surface water systems through quantity control and stormwater treatment. The PP systems provided excellent stormwater treatment for petroleum hydrocarbons, total suspended solids, metals (copper, iron, manganese and zinc) and nutrients (total-nitrogen and total-phosphorus) by reducing event mean concentrations (EMC) as well as total pollutant loadings. The PPs significantly reduced the concentration and loading of ammonia (NH4(+)+NH3), nitrite (NO2(-)) and organic-nitrogen (Org-N) but increased the concentration and loading of nitrate (NO3(-)). The PP systems had mixed performances for the treatment of phosphate (PO4(3-)). The PP systems increased the concentration of sodium (Na) and chloride (Cl) but EMCs remained well below recommended levels for drinking water quality. Relative to the observed runoff, winter road salt was released more slowly from the PP systems resulting in elevated spring and early-summer Cl and Na concentrations in effluent. PP materials were found to introduce dissolved solids into the infiltrating stormwater. The release of these pollutants was verified by additional laboratory scale testing of the individual pavement and aggregate materials at the University of Guelph. Pollutant concentrations were greatest during the first few months after construction and declined rapidly over the course of the study.

  3. Stormwater quality of spring-summer-fall effluent from three partial-infiltration permeable pavement systems and conventional asphalt pavement.

    Science.gov (United States)

    Drake, Jennifer; Bradford, Andrea; Van Seters, Tim

    2014-06-15

    This study examined the spring, summer and fall water quality performance of three partial-infiltration permeable pavement (PP) systems and a conventional asphalt pavement in Ontario. The study, conducted between 2010 and 2012, compared the water quality of effluent from two Interlocking Permeable Concrete Pavements (AquaPave(®) and Eco-Optiloc(®)) and a Hydromedia(®) Pervious Concrete pavement with runoff from an Asphalt control pavement. The usage of permeable pavements can mitigate the impact of urbanization on receiving surface water systems through quantity control and stormwater treatment. The PP systems provided excellent stormwater treatment for petroleum hydrocarbons, total suspended solids, metals (copper, iron, manganese and zinc) and nutrients (total-nitrogen and total-phosphorus) by reducing event mean concentrations (EMC) as well as total pollutant loadings. The PPs significantly reduced the concentration and loading of ammonia (NH4(+)+NH3), nitrite (NO2(-)) and organic-nitrogen (Org-N) but increased the concentration and loading of nitrate (NO3(-)). The PP systems had mixed performances for the treatment of phosphate (PO4(3-)). The PP systems increased the concentration of sodium (Na) and chloride (Cl) but EMCs remained well below recommended levels for drinking water quality. Relative to the observed runoff, winter road salt was released more slowly from the PP systems resulting in elevated spring and early-summer Cl and Na concentrations in effluent. PP materials were found to introduce dissolved solids into the infiltrating stormwater. The release of these pollutants was verified by additional laboratory scale testing of the individual pavement and aggregate materials at the University of Guelph. Pollutant concentrations were greatest during the first few months after construction and declined rapidly over the course of the study. PMID:24681366

  4. SYSTEMATIC FORMULATION OF HIGH PERFORMANCE CONCRETE PAVEMENT

    Directory of Open Access Journals (Sweden)

    Salil Kumar Roy

    2005-01-01

    Full Text Available Following a 25-1 fractional factorial design concept, an experiment was planned ; sixteen experimental mixes were calculated from a basic mix (cement : sand : aggregates : fly ash = 1 : 1.3 : 2.6 : 0.8 and W/C ratio of 0.37 and determined changes (cement = 0.1 ; sand = 0.1 ; aggregates = 0.2 ; fly ash = 0.04 and changing W/C ratio by 0.01 using Taguchi’s orthogonal array. Samples were made from each data point. Compressive strength and water absorption were determined after each of two curing conditions (a 28 days in the water, (b 28 days in the water and 32 days in the air after that. Mix no 12 [Cement : Sand : Gravel : Fly Ash = 0.9 : 1.2 : 2.8 : 0.76] was found to have highest compressive strength and lowest water absorption.

  5. Cold Region Pavements%寒区路面

    Institute of Scientific and Technical Information of China (English)

    GuyDore

    2002-01-01

    The article mainly discusses several essential problems of cold region pavement, including thermal cracking of asphalt concrete, cracking deterioration and heaving, frost heave, seasonal and long term roughness induced by different frost heave, frost heave cracking, bearing capacity loss during spring thaw. The reason for these problems is that cold region pavements are subjected to intense solicitation by climatic and environmental factors. The author offers several models corresponding to the solicitation. Furthermore in conclusion of the article the author indicates future research for cold region.

  6. Self-compacting concrete mixtures for road BUILDING

    Directory of Open Access Journals (Sweden)

    Tran Tuan My

    2012-10-01

    Therefore, effective concrete road pavements require self-compacting though non-segregating concrete mixtures to comply with the pre-set values of their properties, namely, bending and compressive strength, corrosion resistance, freeze resistance, etc. Acting in cooperation with Department of Technology of Binders and Concretes of MSUCE, NIIMosstroy developed and examined a self-compacting cast concrete mixture designated for durable monolithic road pavements. The composition in question was generated by adding a multi-component modifier into the mix. The modifier was composed of a hyperplasticiser, active (structureless fine and crystalline silica, and a concrete hardening control agent.

  7. 结合透水混凝土路面的垂直流要水平流组合人工湿地雨水收集处理系统设计%Constructed Wetland Rainwater Collection and Treatment System Design Combined with the Vertical Flow-Horizontal Flow Combination of Pervious Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    丁权福; 唐硕; 姜慧; 赵云科; 魏梦可; 孙加亮; 丁永昌; 徐栋栋

    2015-01-01

    本文重点阐述了一种结合透水混凝土路面的垂直流—水平流组合人工湿地系统的设计,通过人工湿地填料、植物选择及搭配来改善人工湿地系统处理污水的物理、生物、化学反应,从而提高系统对收集的雨水净化处理能力。%This paper focuses on the design of constructed wetland system combined with the vertical flow-horizontal flow combination of pervious concrete pavement, which can improve the physical, biological and chemical reaction of constructed wetland system treating the polluted water through constructed wetland fillers, plant selection and matching, thereby improving the rainwater purification capability of system.

  8. Comparative Analysis of Mechanical Response of Asphalt Concrete Pavement to Different Loads%不同形式荷载下沥青混凝土路面结构力学响应的对比分析

    Institute of Scientific and Technical Information of China (English)

    陈俊; 陈景雅; 刘云; 吴建涛

    2013-01-01

    Wheel loads in present pavement analysis systems are commonly simplified as three forms,namely static load,vibrating load and moving load with a constant speed.In order to understand the diffe rence of pavement response subject to the three simplified loadings,the discrete element model of pavement structure is constructed according to a typical flexible pavement.The effects of loading on pavement structure are simulated using the discrete element method.Thereafter,comparisons of pavement response subject to the three different loading are performed.Results show that only the maximum response to moving load can be reflected by static and vibration loading.The alternation of tensile and compressive response and double-action of the horizontal shearing stress cannot be simulated by static and vibration loading.%在分析车辆荷载作用下路面结构响应时,车辆荷载通常被简化为静止、振动和匀速移动3类形式.为了准确把握荷载不同简化形式下路面结构响应的差异,根据柔性路面的典型结构形式,建立了路面结构的离散元模型;采用离散元颗粒流软件,分别模拟了静止、振动和移动荷载对路面结构的作用,并对比分析了不同荷载形式下路面结构的力学响应.结果表明,静止、振动荷载只能反映移动荷载作用于路面结构后最大响应,亦即移动荷载越过路面结构某位置的瞬间,静止荷载响应与振动和移动荷载响应的峰值相当;静止、振动荷载不能反映移动荷载对路面结构引起的拉、压交替响应,以及车辆移动引起的路面结构内水平剪应力不同方向的两次作用.

  9. Rheological behaviour of polymer-modified bituminous mastics : a comparative analysis between physical and chemical modification

    OpenAIRE

    Shivokhin, Maxim; García Morales, Moisés; Partal López, Pedro; Cuadri Vega, Antonio Abad; Gallegos Montes, Críspulo

    2012-01-01

    Mastic, a bitumen/filler blend which naturally forms when bitumen is mixed with aggregates is the actual product used to bind coarse mineral particles in the asphalt mixtures. As a result, the characterisation of mastics is essential to improve the understanding of the response and performance of asphalt concrete pavements. On the other hand, the lack of experimental data concerning the behaviour of mastics and, above all, polymer-modified mastics has been lately claimed. In that sense, this ...

  10. Asphalt pavement temperature prediction

    OpenAIRE

    Minhoto, Manuel; Pais, Jorge; Pereira, Paulo

    2006-01-01

    A 3-D finite element model (FEM) was developed to calculate the lemperature of an asphtalt rubber pavement localed in the Northeast of Portugal. The goal of the case study presented in this paper is to show the good accuracy temperature prediction tha can be obtained with this model when compared with the field pavement thermal condition obtained during a year. lnput data to the model are the hourly values for solar radiation and temperature and the mean daily value of wind speed obtained fr...

  11. DRAINAGE AND FLEXIBLE PAVEMENT PERFORMANCE

    Directory of Open Access Journals (Sweden)

    SIDDHARTHA ROKADE

    2012-04-01

    Full Text Available Providing adequate drainage to a pavement system has been considered as an important design consideration to prevent premature failures due to water related problems such as pumping action, loss of support, and rutting, among others. Most water in pavements is due to rainfall infiltration into unsaturated pavement layers, throughjoints, cracks, shoulder edges, and various other defects, especially in older deteriorated pavements. Water also seep upward from a high groundwater table due to capillary suction or vapour movements, or it may flow laterally from the pavement edges and side ditches. Providing adequate drainage to a pavement system has been considered as an important design consideration to ensure satisfactory performance of the pavement, particularly from the perspective of life cycle cost and serviceability. To minimize premature pavement distresses and to enhance the pavement performance, it is imperative to provide adequate drainage to allow infiltrated water to drain out from the base and sub-base, thus avoiding saturation of base and subgrade soils. This paper deals with the analysis of the impact of subsurface drainage on pavement system performance. The requirement ofeffective subsurface drainage for pavement performance is also discussed.

  12. Modelling of the fracture toughness anisotropy in fiber reinforced concrete

    OpenAIRE

    Tarasovs, S.; J. Krūmiņš; V. Tamužs

    2016-01-01

    Steel fiber reinforced concrete is potentially very promising material with unique properties, which currently is widely used in some applications, such as floors and concrete pavements. However, lack of robust and reliable models of fiber reinforced concrete fracture limits its application as structural material. In this work a numerical model is proposed for predicting the crack growth in fiber reinforced concrete. The mixing of the steel fibers with the concrete usually creates...

  13. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    Directory of Open Access Journals (Sweden)

    Dipankar Sarkar

    2016-01-01

    Full Text Available There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46, 0.50, 0.54, and 0.60 of the weight of brick aggregates. Marshall Method of mix design is carried out to find the optimum bitumen content of such bituminous concrete mix prepared by plastic coated OBBA. Bulk density, Marshall Stability, flow, Marshall Quotient, ITS, TSR, stripping, fatigue life, and deformations have been determined accordingly. Marshall Stability value of 0.54 percent of plastic mix is comparatively higher than the other mixes except 0.60 percent of plastic mix. Test results are within the prescribed limit for 0.54 percent of plastic mix. There is a significant reduction in rutting characteristics of the same plastic mix. The fatigue life of the mix is also significantly higher. Thus plastic coated OBBA is found suitable in construction of bituminous concrete road.

  14. 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.

  15. Cooler reflective pavements give benefits beyond energy savings: durability and illumination

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, Melvin; Akbari, Hashem; Harvey, John T.

    2000-06-01

    City streets are usually paved with asphalt concrete because this material gives good service and is relatively inexpensive to construct and maintain. We show that making asphalt pavements cooler, by increasing their reflection of sunlight, may lead to longer lifetime of the pavement, lower initial costs of the asphalt binder, and savings on street lighting and signs. Excessive glare due to the whiter surface is not likely to be a problem.

  16. Cooler reflective pavements give benefits beyond energy savings: durability and illumination

    International Nuclear Information System (INIS)

    City streets are usually paved with asphalt concrete because this material gives good service and is relatively inexpensive to construct and maintain. We show that making asphalt pavements cooler, by increasing their reflection of sunlight, may lead to longer lifetime of the pavement, lower initial costs of the asphalt binder, and savings on street lighting and signs. Excessive glare due to the whiter surface is not likely to be a problem

  17. 农村公路路面结构选型探讨%Discussion of Type Selection for Pavement Structure of Rural Highway

    Institute of Scientific and Technical Information of China (English)

    牛芙运

    2011-01-01

    According to present situation of rural highway pavement structure and considering of characteristic of aspect concrete pavement and cement concrete pavement, the influence factors for pavement structure type selection was analyzed systematically. Then two-stage influence factors table was proposed for pavement structure selection in rural highway. The study conducted in this paper provides reference for pavement structure selection of rural highway.%针对农村公路路面结构现状,基于沥青混凝土和水泥混凝土两类路面的特点,全面系统地分析了路面结构选型的影响因素,建立了农村公路路面选型的两级影响因素依据表,为农村公路路面选型提供参考.

  18. Evaluation of a highway pavement using non destructive tests: Falling Weight Deflectometer and Ground Penetrating Radar

    Science.gov (United States)

    Marecos, Vania; Fontul, Simona; de Lurdes Antunes, Maria

    2015-04-01

    This paper presents the results of the application of Falling Weight Deflectometer (FWD) and Ground Penetrating Radar (GPR) to assess the bearing capacity of a rehabilitated flexible highway pavement that began to show the occurrence of cracks in the surface layer, about one year after the improvement works. A visual inspection of the surface of the pavement was performed to identify and characterize the cracks. Several core drills were done to analyse the cracks propagation in depth, these cores were also used for GPR data calibration. From the visual inspection it was concluded that the development of the cracks were top-down and that the cracks were located predominantly in the wheel paths. To determine the thickness of the bituminous and granular layers GPR tests were carried out using two horn antennas of 1,0 GHz and 1,8 GHz and a radar control unit SIR-20, both from GSSI. FWD load tests were performed on the wheel paths and structural models were established, based on the deflections measured, through back calculation. The deformation modulus of the layers was calculated and the bearing capacity of the pavement was determined. Summing up, within this study the GPR was used to continuously detect the layer thickness and the GPR survey data was calibrated with core drills. The results showed variations in the bituminous layer thickness in comparison to project data. From the load tests it was concluded that the deformation modulus of the bituminous layers were also vary variable. Limitations on the pavement bearing capacity were detected in the areas with the lower deformation modulus. This abstract is of interest for COST Action TU1208 Civil Engineering Applications of Ground Penetrating Radar.

  19. Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods.

    Science.gov (United States)

    Li, Hui; Kayhanian, Masoud; Harvey, John T

    2013-03-30

    Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50-90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability.

  20. Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods.

    Science.gov (United States)

    Li, Hui; Kayhanian, Masoud; Harvey, John T

    2013-03-30

    Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50-90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability. PMID:23434738

  1. Modeling of unsaturated granular materials in flexible pavements

    Directory of Open Access Journals (Sweden)

    Gu Fan

    2016-01-01

    Full Text Available The unsaturated granular material (UGM is found to exhibit the moisture-sensitive and stress-dependent nonlinear cross-anisotropic behaviour in flexible pavements. This paper aims at developing a finite element (FE model for pavement structure, which takes into account this behaviour of UGM. First, the Lytton model is employed to characterize the moisture-sensitive and stress-dependent behaviour of UGM, which incorporated a matric suction term to the existing stress-dependent constitutive model. The Lytton model is validated by the laboratory resilient modulus tests on the selected UGMs at different moisture contents. Second, the nonlinear cross-anisotropic constitutive equation of UGM is derived from the generalized Hooke’s Law. The coefficients of the constitutive model are determined by the rapid triaxial test. Third, a User-Defined Material (UMAT subroutine is developed to characterize this constitutive behaviour in the FE software ABAQUS. The UMAT subroutine adopts the secant stiffness approach with multiple damping factors. The UMAT subroutine is then implemented in the FE model of flexible pavement structures. The FE simulation results indicate the nonlinear cross-anisotropic model predicts greater pavement responses than the isotropic model. When the UGM is suction sensitive, it is found that the moisture content of UGM significantly affects the moduli distribution of base layer and the critical strains (i.e., tensile strain at the bottom of asphalt concrete, and compressive strains in base and subgrade layers of pavement structures.

  2. Design of Rigid and Flexible Pavements by Various Methods & Their Cost Analysis of Each Method

    Directory of Open Access Journals (Sweden)

    Saurabh Jain

    2013-09-01

    Full Text Available Highway and pavement design plays an important role in the DPR projects. The satisfactory performance of the pavement will result in higher savings in terms of vehicle operating costs and travel time, which has a bearing on the overall economic feasibility of the project. This paper discusses about the design methods that are traditionally being followed and examines the “Design of rigid and flexible pavements by various methods & their cost analysis by each method”. Flexible pavement are preferred over cement concrete roads as they have a great advantage that these can be strengthened and improved in stages with the growth of traffic and also their surfaces can be milled and recycled for rehabilitation. The flexible pavements are less expensive also with regard to initial investment and maintenance. Although Rigid pavement is expensive but have less maintenance and having good design period. The economic part are carried out for the design pavement of a section by using the result obtain by design method and their corresponding component layer thickness. It can be done by drawing comparisons with the standard way and practical way. This total work includes collection of data analysis various flexible and rigid pavement designs and their estimation procedure are very much useful to engineer who deals with highways.

  3. Finite Element Investigation of the Deterioration of Doweled Rigid Pavements

    CERN Document Server

    Ghauch, Ziad G

    2011-01-01

    The purpose of this study is to describe the failure of concrete around dowel bars in jointed rigid pavements, and the resulting effect on the pavement performance. In fact, under repetitive vehicle loading, concrete in contact with the dowel bar deteriorates, particularly at the joint face. The degradation of concrete around the dowel negatively affects the latter's performance in terms of transferring wheel loads through vertical shear action. In this context, a nonlinear 3D Finite Element analysis was performed using the commercial FE code Abaqus (v-6.11). The FE model was validated with classical analytical solutions of shear and moment along the dowel. A concrete damaged plasticity model was used for the PCC slab to model the degradation of concrete matrix around the dowels under incremental loading. Results obtained show, among other things, that the degradation of concrete matrix around the dowel was found to initiate at the face of the joint and propagate towards the interior of the dowel. Also, resul...

  4. Investigations of the dynamics of road pavement reflectance

    Institute of Scientific and Technical Information of China (English)

    Kang Jiang; Kai Yu; Yongchao Zhao

    2012-01-01

    Road pavement reflectance is usually assumed to be invariant in short periods of time in some quantitative remote sensing applications. To examine its variability,reflectance sequences of concrete and asphalt pavement are measured in field for half a day in visible and near-infarecd (VNIR) spectral range using dual-beam method.As much as 20.7% and 3.52% of relative changes are found in asphalt and concrete reflectance data at 550 nm,and all VNIR bands demonstrate similar variations found to correlate with both illumination geometry and the relative portion of diffuse irradiance.In this letter,this effect is interpreted from a mathematic view.Further studies are needed to model the dynamics of reflectance physically.

  5. Identifying Fine Aggregates Prone to Polishing in PCC Pavements

    OpenAIRE

    Fowler, David W; Rached, Marc M.

    2012-01-01

    Surface polishing in portland cement concrete (PCC) pavements leads to higher incidences of skid-related accidents on highways. This type of failure is often associated with the usage of softer fine aggregate such as limestone sands. To identify polish resistance aggregates, state agencies like TxDOT have adopted tests such as the acid insoluble residue test (AIR). Since calcium carbonate is soluble in acid, no carbonate sand passes the AIR test which has a minimum limit of 60% in Texas. This...

  6. Comparative Study on Pavement Temperature Features of Bridge Deck and Road Pavement

    OpenAIRE

    Yueqin Hou; Nanxiang Zheng; Yiluo Zhang

    2013-01-01

    The objective of this study was to comparatively analyze the difference of pavement temperature of bride deck and road pavement. The asphalt pavement temperature of road pavement and bride deck were tested in Guozigou area of Xinjiang, China. And the air temperature, wind speed, humidness and sunlight radiation were collected. Further, the distribution features of asphalt pavement of bridge deck and road pavement were comparatively analyzed. At last, the predictive model of pavement temperatu...

  7. Runoff on Pavements of Soil-Cement Blocks – an Experimental Boarding

    Directory of Open Access Journals (Sweden)

    Zegarra-Tarqui Jorge Luis

    2015-01-01

    Full Text Available The article evaluates the reduction of runoff in pavements constructed with rectangular blocks of soil-cement. The tests were conducted in a pilot pavement built with soil-cement blocks, seated in a metal box of 50 cm × 50 cm (area = 2500 cm2, with declivities of 1%, 3% and 5%. Mean intensities of 76.9 mm / I 117.7 mm / h were used, values close to the intensities calculated by intensity-frequency-duration (i-f- -d equation of the city of Salvador, Brazil, for return periods of 2 and 5 years, respectively. The medium runoff coefficient was C = 0.61, this value is close to the coefficient of pavement with rectangular blocks (C = 0.6 and it has a lower value than the coefficient for concrete block pavement (C = 0.78. On the other hand, considering that areas with more than 2500 cm2 are constituted by coupling of area units of 50 cm × 50 cm, the splash losses are part of the runoff, obtaining the coefficient Csuperficial + splashing, which showed values in the 0.74 to 0.89 range, these values were found close to the coefficient of concrete block pavement (C = 0.78 and below the concrete pavement (C = 0.95, respectively, but factors such as displacement time of runoff on surface, depressions on the surface, roughness of pavement, evaporation and others, should reduce this value. Then, the pavement of soil-cement blocks can be considered in the category of semi-permeable for the area size used.

  8. Time dependent viscoelastic rheological response of pure, modified and synthetic bituminous binders

    Science.gov (United States)

    Airey, G. D.; Grenfell, J. R. A.; Apeagyei, A.; Subhy, A.; Lo Presti, D.

    2016-08-01

    Bitumen is a viscoelastic material that exhibits both elastic and viscous components of response and displays both a temperature and time dependent relationship between applied stresses and resultant strains. In addition, as bitumen is responsible for the viscoelastic behaviour of all bituminous materials, it plays a dominant role in defining many of the aspects of asphalt road performance, such as strength and stiffness, permanent deformation and cracking. Although conventional bituminous materials perform satisfactorily in most highway pavement applications, there are situations that require the modification of the binder to enhance the properties of existing asphalt material. The best known form of modification is by means of polymer modification, traditionally used to improve the temperature and time susceptibility of bitumen. Tyre rubber modification is another form using recycled crumb tyre rubber to alter the properties of conventional bitumen. In addition, alternative binders (synthetic polymeric binders as well as renewable, environmental-friendly bio-binders) have entered the bitumen market over the last few years due to concerns over the continued availability of bitumen from current crudes and refinery processes. This paper provides a detailed rheological assessment, under both temperature and time regimes, of a range of conventional, modified and alternative binders in terms of the materials dynamic (oscillatory) viscoelastic response. The rheological results show the improved viscoelastic properties of polymer- and rubber-modified binders in terms of increased complex shear modulus and elastic response, particularly at high temperatures and low frequencies. The synthetic binders were found to demonstrate complex rheological behaviour relative to that seen for conventional bituminous binders.

  9. Time dependent viscoelastic rheological response of pure, modified and synthetic bituminous binders

    Science.gov (United States)

    Airey, G. D.; Grenfell, J. R. A.; Apeagyei, A.; Subhy, A.; Lo Presti, D.

    2016-04-01

    Bitumen is a viscoelastic material that exhibits both elastic and viscous components of response and displays both a temperature and time dependent relationship between applied stresses and resultant strains. In addition, as bitumen is responsible for the viscoelastic behaviour of all bituminous materials, it plays a dominant role in defining many of the aspects of asphalt road performance, such as strength and stiffness, permanent deformation and cracking. Although conventional bituminous materials perform satisfactorily in most highway pavement applications, there are situations that require the modification of the binder to enhance the properties of existing asphalt material. The best known form of modification is by means of polymer modification, traditionally used to improve the temperature and time susceptibility of bitumen. Tyre rubber modification is another form using recycled crumb tyre rubber to alter the properties of conventional bitumen. In addition, alternative binders (synthetic polymeric binders as well as renewable, environmental-friendly bio-binders) have entered the bitumen market over the last few years due to concerns over the continued availability of bitumen from current crudes and refinery processes. This paper provides a detailed rheological assessment, under both temperature and time regimes, of a range of conventional, modified and alternative binders in terms of the materials dynamic (oscillatory) viscoelastic response. The rheological results show the improved viscoelastic properties of polymer- and rubber-modified binders in terms of increased complex shear modulus and elastic response, particularly at high temperatures and low frequencies. The synthetic binders were found to demonstrate complex rheological behaviour relative to that seen for conventional bituminous binders.

  10. Hydraulic design of pervious concrete highway shoulders

    Science.gov (United States)

    Grahl, Nathan Andrew

    Stormwater drainage has been a factor in roadway design for years. Now stormwater quantity and quality are also becoming regulated for roadways. As regulations of stormwater management continue to increase so does the need for more viable and effect management practices. The research presented and discussed in this thesis presents the option of using pervious concrete in highway shoulders as a best management practice for stormwater management. Research focused on the hydraulic response of pervious concrete pavements exposed to sheet flowing water. Pervious concrete samples were placed in a hydraulic flume to determine capture discharges, infiltration rates, and by-pass flowrates for a broad range of void contents, across a broad range of pavement cross slopes. The results demonstrate that the capture discharge and infiltration rates are inversely related to the cross slope of the pavement. Results also showed the infiltration rate of the permeable pavement exposed to sheet flowing water, in the model, is significantly lower than the measured infiltration rate. Pervious concrete samples were also tested to determine hydraulic response when exposed to clogging associated with sand used in roadway de-icing. The results of the clogging of the permeable pavements followed similar trends as the unclogged samples, with the only difference being a more significant reduction in infiltration rates at higher applications of sand. Preliminary discussion of a design methodology is included with a design example.

  11. Effects of Using Silica Fume and Polycarboxylate-Type Superplasticizer on Physical Properties of Cementitious Grout Mixtures for Semiflexible Pavement Surfacing

    Science.gov (United States)

    Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S.; Katman, Herdayati; Husain, Nadiah Md

    2014-01-01

    Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout. PMID:24526911

  12. Effects of using silica fume and polycarboxylate-type superplasticizer on physical properties of cementitious grout mixtures for semiflexible pavement surfacing.

    Science.gov (United States)

    Koting, Suhana; Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S; Ibrahim, Mohd Rasdan; Katman, Herdayati; Husain, Nadiah Md

    2014-01-01

    Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout. PMID:24526911

  13. Effects of Using Silica Fume and Polycarboxylate-Type Superplasticizer on Physical Properties of Cementitious Grout Mixtures for Semiflexible Pavement Surfacing

    Directory of Open Access Journals (Sweden)

    Suhana Koting

    2014-01-01

    Full Text Available Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout.

  14. Three Permeable Pavements Performances for Priority Metal Pollutants and Metals Associated with Deicing Chemicals from Edison Parking Lot, NJ

    Science.gov (United States)

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  15. Three Permeable Pavements Performances for Priority Metal Pollutants and Metals associated with Deicing Chemicals from Edison Parking Lot, NJ - abstract

    Science.gov (United States)

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  16. Use of Ground Penetrating Radar at the FAA's National Airport Pavement Test Facility

    Science.gov (United States)

    Injun, Song

    2015-04-01

    The Federal Aviation Administration (FAA) in the United States has used a ground-coupled Ground Penetrating Radar (GPR) at the National Airport Pavement Test Facility (NAPTF) since 2005. One of the primary objectives of the testing at the facility is to provide full-scale pavement response and failure information for use in airplane landing gear design and configuration studies. During the traffic testing at the facility, a GSSI GPR system was used to develop new procedures for monitoring Hot Mix Asphalt (HMA) pavement density changes that is directly related to pavement failure. After reviewing current setups for data acquisition software and procedures for identifying different pavement layers, dielectric constant and pavement thickness were selected as dominant parameters controlling HMA properties provided by GPR. A new methodology showing HMA density changes in terms of dielectric constant variations, called dielectric sweep test, was developed and applied in full-scale pavement test. The dielectric constant changes were successfully monitored with increasing airplane traffic numbers. The changes were compared to pavement performance data (permanent deformation). The measured dielectric constants based on the known HMA thicknesses were also compared with computed dielectric constants using an equation from ASTM D4748-98 Standard Test Method for Determining the Thickness of Bound Pavement Layers Using Short-Pulse Radar. Six inches diameter cylindrical cores were taken after construction and traffic testing for the HMA layer bulk specific gravity. The measured bulk specific gravity was also compared to monitor HMA density changes caused by aircraft traffic conditions. Additionally this presentation will review the applications of the FAA's ground-coupled GPR on embedded rebar identification in concrete pavement, sewer pipes in soil, and gage identifications in 3D plots.

  17. Geotextiles in Flexible Pavement Construction

    Science.gov (United States)

    Alungbe, Gabriel D.

    2004-01-01

    People everywhere in the developed world regularly drive on paved roads. Learning about the construction techniques and materials used in paving benefits technology and construction students. This article discusses the use of geosynthetic textiles in pavement construction. It presents background on pavements and describes geotextiles and drainage…

  18. Pavement roughness and skid properties

    Science.gov (United States)

    Road roughness and roadway safety as it relates to both surface and air transportation are discussed. The role of road roughness in vehicle ride, the measurement of roughness, the evaluation of riding confort, and the effect of grooving pavements are discussed. The effects of differential pavement friction on the response of cars in skidding maneuvers is discussed.

  19. Study on Influence Factors of Anti-shear Performance of High Grade Asphalt Concrete Pavement%高等级沥青混凝土路面抗剪性能影响因素研究

    Institute of Scientific and Technical Information of China (English)

    王志强

    2014-01-01

    Based on the multilayered elastic system theory and the GAMES software,considering the thickness of pavement structure courses,the stiffness and the interface condition,the paper analyzed the change law of anti-shear performance of the asphalt pavement.The results show that:the effect of the thickness of the surface course and the base course on the asphalt pavement is insignificant,so it is a waste of cost to increase the thickness of the surface course and the base course to enhance the shearing capability;the shear stress peak value in the surface course would be reduced by increasing the modulus of base course,but the change is not obvious,which indicates that it does little to promote the anti-shear performance by increasing the modulus of base course;the more the modulus ratio between the wearing course and the mid-course,the greater the shear stress peak value in the surface course,which can be ob-viously seen;the shear stress peak value in the surface course would be reduced by the decrease of inter-facial bonding performance.%运用多层弹性体系理论,以 GAMES 软件为力学分析工具,考虑路面结构层厚度、基面层模量及层间状态等因素,分析沥青路面抗剪性能的变化规律。结果表明:沥青路面剪应力峰值受面层厚度和基层厚度影响不明显,通过增加面层厚度和基层厚度提高路面抗剪性能加重了经济成本,收效甚微;面层内剪应力峰值随基层模量增加而减小,但变化不明显,说明增加基层模量对沥青路面抗剪性能的提高作用不大;上面层与中面层模量比越大,上面层内剪应力峰值越大,且这种影响较为明显;在层间粘结减弱的过程中,面层内最大剪应力峰值随之减小。

  20. Procedures and Technologies for Pavement Monitoring

    OpenAIRE

    GEORGE, Luc Amaury; Brosseaud, Yves

    2009-01-01

    Pavement Monitoring (surface and structure). Surface characteristics - main indicators Pavement structures (non destructive testings). Monitoring objectives. Devices and indicators used in France Innovation & Research. Measurement's use by roads owners. Main road network (States & motorway concessionaires). Local and urban road networks. Some maintenance techniques. High modulus mixtures and very thin mixtures. Pavement in situ recycling Pavement in plan recycling. Low noise & coloured ...

  1. An Optimization Model for Design of Asphalt Pavements Based on IHAP Code Number 234

    Directory of Open Access Journals (Sweden)

    Ali Reza Ghanizadeh

    2016-01-01

    Full Text Available Pavement construction is one of the most costly parts of transportation infrastructures. Incommensurate design and construction of pavements, in addition to the loss of the initial investment, would impose indirect costs to the road users and reduce road safety. This paper aims to propose an optimization model to determine the optimal configuration as well as the optimum thickness of different pavement layers based on the Iran Highway Asphalt Paving Code Number 234 (IHAP Code 234. After developing the optimization model, the optimum thickness of pavement layers for secondary rural roads, major rural roads, and freeways was determined based on the recommended prices in “Basic Price List for Road, Runway and Railway” of Iran in 2015 and several charts were developed to determine the optimum thickness of pavement layers including asphalt concrete, granular base, and granular subbase with respect to road classification, design traffic, and resilient modulus of subgrade. Design charts confirm that in the current situation (material prices in 2015, application of asphalt treated layer in pavement structure is not cost effective. Also it was shown that, with increasing the strength of subgrade soil, the subbase layer may be removed from the optimum structure of pavement.

  2. Effects on evaporation rates from different water-permeable pavement designs.

    Science.gov (United States)

    Starke, P; Göbel, P; Coldewey, W G

    2011-01-01

    The urban water balance can be attenuated to the natural by water-permeable pavements (WPPs). Furthermore, WPPs have a 16% higher evaporation rate than impermeable pavements, which can lead to a better urban climate. Evaporation rates from pavements are influenced by the pavement surface and by the deeper layers. By a compared evaporation measurement between different WPP designs, the grain size distribution of the sub-base shows no influence on the evaporation rates in a significant way. On the contrary, a sub-base made of a twin-layer decreases the evaporation by 16% compared to a homogeneous sub-base. By a change in the colour of the paving stone, 19% higher evaporation rates could be achieved. A further comparison shows that the transpiration-effect of the grass in grass pavers increases the evaporation rates more than threefold to pervious concrete pavements. These high evapotranspiration rates can not be achieved with a pervious concrete paving stone. In spite of this, the broad field of application of the pervious concrete paving stone increases the importance in regard to the urban climate.

  3. Effects on evaporation rates from different water-permeable pavement designs.

    Science.gov (United States)

    Starke, P; Göbel, P; Coldewey, W G

    2011-01-01

    The urban water balance can be attenuated to the natural by water-permeable pavements (WPPs). Furthermore, WPPs have a 16% higher evaporation rate than impermeable pavements, which can lead to a better urban climate. Evaporation rates from pavements are influenced by the pavement surface and by the deeper layers. By a compared evaporation measurement between different WPP designs, the grain size distribution of the sub-base shows no influence on the evaporation rates in a significant way. On the contrary, a sub-base made of a twin-layer decreases the evaporation by 16% compared to a homogeneous sub-base. By a change in the colour of the paving stone, 19% higher evaporation rates could be achieved. A further comparison shows that the transpiration-effect of the grass in grass pavers increases the evaporation rates more than threefold to pervious concrete pavements. These high evapotranspiration rates can not be achieved with a pervious concrete paving stone. In spite of this, the broad field of application of the pervious concrete paving stone increases the importance in regard to the urban climate. PMID:22049757

  4. 论沥青路面早期损坏的预防措施%Discussion on prevention measures of early damages of asphalt pavement

    Institute of Scientific and Technical Information of China (English)

    汪香莲

    2011-01-01

    Combining with the present asphalt concrete pavement construction and caused pavement early damages,this paper analysed the reasons and preventive measures of pavement early damages from pavement structure layer,mixing ratio design,raw materials,construction control and other aspects,in order to reduce the early damage of asphalt pavement,prolong the service life of pavement.%结合当前沥青混凝土路面施工及产生的路面早期破坏,从路面结构层、配合比设计、原材料、施工控制等方面分析了路面早期破坏的原因及预防措施,以减少沥青路面早期损坏,延长路面使用寿命。

  5. 让城市自由呼吸——关于透水混凝土用于城市生态道路铺装的探讨%Make the city breathe freely——Discussion about Previous concrete used in Ecological road pavement

    Institute of Scientific and Technical Information of China (English)

    张力; 张林

    2009-01-01

    透水混凝土是一种能减轻环境负担、与自然环境协调共生,能为人类构造舒适生活环境的功能材料,既具有透气性、保水性、通气性,容重小并保留混凝土强度高的特点,同时又能满足路用及铺地强度和耐久性要求的地面铺装.目前,国内透水性混凝土已经在各个城市广泛应用,其在缓解城市热岛效应、减小地表径流、补充地下水资源、截留渗透雨水有效遏制城市内涝等方面发挥重要的作用.本文重点阐述了透水混凝土的应用在建设现代生态城市中发挥的重要作用.%Previous concrete is a kind of functional materials which can reduce the burden on the environment,symbiotic coordination with the natural environment and construct a comfortable living environment of human,and not only with the features of air permeability, water-holding capacity, aeration, bulk density of small and re-tain the characteristics of high concrete strength,but also meet the road use and the strength and durability re-quirements of the ground pavement.At present, Previous Concrete is widely used in various cities,which plays an important role in easing Urban Heat Island Effect, reducing Surface runoff, addeding groundwater Resources, inter-cepting infiltration of rainwater in order to contain City watedogging effectively,and so on. This article focuses on the application of pervious concrete in the construction of a modern eco-city played an important role.

  6. Investigation of activity release from bituminized intermediate-level waste forms under thermal stresses

    International Nuclear Information System (INIS)

    To determine the consequences of a fire during fabrication, intermediate storage and transport of bituminized NaNO3 waste forms, the fractions of plutonium released from the waste forms were assessed. For this purpose, laboratory tests were made with PuO2-containing specimens as well as a field test with specimens containing Eu2O3. By the evaluation of plutonium release in the laboratory and by the determination of the total sodium release and the relative Eu/Na release in the field tests the plutonium release can be deduced from full-scale specimens. The results show that for bituminized waste forms with high NaNO3 contents (approx. 36 wt%) the average plutonium release obtained in laboratory testing is 15%. In the field tests (IAEA fire test conditions) an average Eu release of 8% was found. These results justify the statement that also for waste forms in open 175 L drum inserts a maximum plutonium release of about 15% can be expected. From the time-dependence of Eu/Na release in the field tests an induction period of 15-20 minutes between the start of testing and the first Na/Eu release can be derived. The maximum differential Na/Eu release occurs after a test period of 45 to 60 minutes duration and after 90 to 105 minutes (tests K2 and K4, respectively); after that time also the highest temperatures in the products are measured. The release values were determined for products in open 175 L drum inserts which in this form are not eligible for intermediate and ultimate storage. For bituminized waste forms in concrete packages (lost concrete shieldings) a delayed increase in temperature to only 70-80 deg. C takes place (4-5 hours after extinction of the fire) if the fire lasts 45 minutes. The concrete package remains intact under test conditions. This means that activity release from bituminized waste forms packaged in this way can be ruled out in the case under consideration. (author)

  7. Fore and aft elastic response characteristics of 34 x 9.9, type 7, 14 ply-rating aircraft tires of bias-ply, bias-belted, and radial-belted design. M.S. Thesis - George Washington Univ., May 1973; [static and rolling tests on dry concrete pavements

    Science.gov (United States)

    Tanner, J. A.

    1974-01-01

    An investigation was conducted to determine the fore-and-aft elastic response characteristics of 34 x 9.9, type VII, 14 ply-rating aircraft tires of bias-ply, bias-belted, and radial-belted design. The investigation consisted of static and rolling tests on dry concrete pavements at the Langley aircraft landing loads and traction facility; statistical techniques which related the measured tire elastic characteristics to variations in the vertical load, inflation pressure, braking force and/or tire vertical deflection; and a semiempirical analysis which related the tire elastic behavior to measured wheel slippage during steady-state braking. The bias-belted tire developed the largest spring constant value for most loading conditions; the radial-belted tire, the smallest. The elastic response of the tire free periphery to static braking included both tread stretch and carcass torsional wind-up about the axle for the bias-ply and bias-belted tires and carcass wind-up alone for the radial-belted tire.

  8. Response Modelling of Bitumen, Bituminous Mastic and Mortar

    NARCIS (Netherlands)

    Woldekidan, M.F.

    2011-01-01

    This research focuses on testing and modelling the viscoelastic response of bituminous binders. The main goal is to find an appropriate response model for bituminous binders. The desired model should allow implementation into numerical environments such as ABAQUS. On the basis of such numerical envi

  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. Methods to Use Surface Infiltration Tests in Permeable Pavement Systems to Determine Maintenance Frequency

    Science.gov (United States)

    Currently, there is limited guidance on selecting test sites to measure surface infiltration rates in permeable pavement systems to determine maintenance frequency. The ASTM method (ASTM C1701) for measuring infiltration rate of in-place pervious concrete suggest to either (1) p...

  11. Agency and Design: Pavement Failure in the Transmilenio Project, Bogotá, Colombia

    DEFF Research Database (Denmark)

    Pineda, Andres Felipe Valderrama

    Transmilenio is the world’s first mass rapid bus transit system designed and built for the city of Bogotá, Colombia. Its first phase was developed and built during the years 1998-2000. The concrete pavement of the cities main corridor, Avenida Caracas and Autopista Norte, was designed and re...

  12. Application of Rubber Asphalt Concrete Pavement in Port Area Roads%橡胶沥青混凝土路面在港区道路中的应用

    Institute of Scientific and Technical Information of China (English)

    莫晓华

    2015-01-01

    In allusion to heavy load traffic feature of port roads,this paper carries out indoor uniaxial compression test,wheel rutting test and bending test of small beams for rubber asphalt mixture.The results show that the elastic modulus and high -temperature property of rubber asphalt mixture are equivalent to SBS modified asphalt mixture,but fatigue performance is the best and above 1 time higher than matrix asphalt mixture.The paper applies rubber asphalt mixture to test sections,and the results show that the surface water seepage coefficient,compactness of mixture,structure depth and surface resistant coefficient of rubber asphalt pavement can satisfy the basic requirements of the specifications.On the basis of test, the paper proposes pavement structural form 4cm rubber asphalt AC -13 +6cm matrix asphalt AC -20 applicable to port roads.%针对港区道路的重载交通特性,进行橡胶沥青混合料室内单轴压缩试验、车辙试验及小梁弯曲试验。结果表明:橡胶沥青混合料的回弹模量、高温性能与 SBS 改性沥青混合料相当,但其疲劳性能最好,比基质沥青混合料高1倍多。将橡胶沥青混合料用于试验路段,结果表明:橡胶沥青路面的路表渗水系数、混合料压实度、构造深度以及表面抗滑系数都能够满足规范基本要求。基于试验,提出港区道路适用的路面结构形式为4 cm 橡胶沥青 AC -13+6 cm 基质沥青 AC -20。

  13. Determining the healing potential of asphalt concrete mixtures--a pragmatic approach

    NARCIS (Netherlands)

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

    2012-01-01

    Most design methods for pavements use a factor explaining the difference between pavement life predictions from design models and performance in the road [1]. Part of this correction factor is healing, the natural capacity of asphalt concrete to recover in rest periods, which generally are not prese

  14. Mechanics based model for predicting structure-induced rolling resistance (SRR) of the tire-pavement system

    Science.gov (United States)

    Shakiba, Maryam; Ozer, Hasan; Ziyadi, Mojtaba; Al-Qadi, Imad L.

    2016-05-01

    The structure-induced rolling resistance of pavements, and its impact on vehicle fuel consumption, is investigated in this study. The structural response of pavement causes additional rolling resistance and fuel consumption of vehicles through deformation of pavement and various dissipation mechanisms associated with inelastic material properties and damping. Accurate and computationally efficient models are required to capture these mechanisms and obtain realistic estimates of changes in vehicle fuel consumption. Two mechanistic-based approaches are currently used to calculate vehicle fuel consumption as related to structural rolling resistance: dissipation-induced and deflection-induced methods. The deflection-induced approach is adopted in this study, and realistic representation of pavement-vehicle interactions (PVIs) is incorporated. In addition to considering viscoelastic behavior of asphalt concrete layers, the realistic representation of PVIs in this study includes non-uniform three-dimensional tire contact stresses and dynamic analysis in pavement simulations. The effects of analysis type, tire contact stresses, pavement viscoelastic properties, pavement damping coefficients, vehicle speed, and pavement temperature are then investigated.

  15. Preliminary evaluation of the lifecycle costs and market barriers of reflective pavements; TOPICAL

    International Nuclear Information System (INIS)

    The objective of this study is to evaluate the life cycle costs and market barriers associated with using reflective paving materials in streets and parking lots as a way to reduce the urban heat island effect. We calculated and compared the life cycle costs of conventional asphalt concrete (AC) pavements to those of other existing pavement technologies with higher reflectivity-portland cement concrete (PCC), porous pavements, resin pavements, AC pavements using light-colored chip seals, and AC pavements using light-colored asphalt emulsion additives. We found that for streets and parking lots, PCC can provide a cost-effective alternative to conventional AC when severely damaged pavements must be completely reconstructed. We also found that rehabilitating damaged AC streets and intersections with thin overlays of PCC (ultra-thin white topping) can often provide a cost-effective alternative to standard rehabilitation techniques using conventional AC. Chip sealing is a common maintenance treatment for low-volume streets which, when applied using light-colored chips, could provide a reflective pavement surface. If the incremental cost of using light-colored chips is low, this chip sealing method could also be cost-effective, but the incremental costs of light-colored chips are as of yet uncertain and expected to vary. Porous pavements were found to have higher life cycle costs than conventional AC in parking lots, but several cost-saving features of porous pavements fell outside the boundaries of this study. Resin pavements were found to be only slightly more expensive than conventional AC, but the uncertainties in the cost and performance data were large. The use of light-colored additives in asphalt emulsion seal coats for parking lot pavements was found to be significantly more expensive than conventional AC, reflecting its current niche market of decorative applications. We also proposed two additional approaches to increasing the reflectivity of conventional AC

  16. Preliminary evaluation of the lifecycle costs and market barriers of reflective pavements

    Energy Technology Data Exchange (ETDEWEB)

    Ting, M.; Koomey, J.G.; Pomerantz, M.

    2001-11-21

    The objective of this study is to evaluate the life cycle costs and market barriers associated with using reflective paving materials in streets and parking lots as a way to reduce the urban heat island effect. We calculated and compared the life cycle costs of conventional asphalt concrete (AC) pavements to those of other existing pavement technologies with higher reflectivity-portland cement concrete (PCC), porous pavements, resin pavements, AC pavements using light-colored chip seals, and AC pavements using light-colored asphalt emulsion additives. We found that for streets and parking lots, PCC can provide a cost-effective alternative to conventional AC when severely damaged pavements must be completely reconstructed. We also found that rehabilitating damaged AC streets and intersections with thin overlays of PCC (ultra-thin white topping) can often provide a cost-effective alternative to standard rehabilitation techniques using conventional AC. Chip sealing is a common maintenance treatment for low-volume streets which, when applied using light-colored chips, could provide a reflective pavement surface. If the incremental cost of using light-colored chips is low, this chip sealing method could also be cost-effective, but the incremental costs of light-colored chips are as of yet uncertain and expected to vary. Porous pavements were found to have higher life cycle costs than conventional AC in parking lots, but several cost-saving features of porous pavements fell outside the boundaries of this study. Resin pavements were found to be only slightly more expensive than conventional AC, but the uncertainties in the cost and performance data were large. The use of light-colored additives in asphalt emulsion seal coats for parking lot pavements was found to be significantly more expensive than conventional AC, reflecting its current niche market of decorative applications. We also proposed two additional approaches to increasing the reflectivity of conventional AC

  17. Permanent deformation of flexible pavements

    Science.gov (United States)

    Brown, S. F.; Broderick, B. V.; Pappin, J. W.

    1980-06-01

    Seven pairs of pavements with granular bases were tested under controlled conditions. One pavement in each pair contained fabric inclusions. An improved testing facility was developed, including: (1) servo-hydraulic system for the loading carriage; (2) amplification and read-out system for pressure cells; (3) linearizing unit for strain coils; (4) transducers for measuring vertical and resilient deflection; (5) techniques for measuring in situ strain on fabric inclusions; (6) extensive use of nuclear density meter to monitor pavement and foundation materials. The following conclusions are drawn: (1) No improvement in performance resulted from fabric inclusions. (2) No consistent reduction in in-situ stresses, resilient strains, or permanent strains was observed as a result of fabric inclusion. (3) No consistent improvement in densities resulted from fabric inclusions. (4) Some slip apparently occurred between fabric and soil on those pavements which involved large deformations. The slip occurred between fabric and crushed limestone base rather than between fabric and silty-clay subgrade.

  18. Radon concentration measurements in bituminous coal mines

    International Nuclear Information System (INIS)

    Radon measurements were carried out in Kozlu, Karadon and Uezuelmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m-3. It is suggested that the ventilation rates should be rearranged to reduce the radon concentration. (authors)

  19. Radon concentration measurements in bituminous coal mines.

    Science.gov (United States)

    Fisne, Abdullah; Okten, Gündüz; Celebi, Nilgün

    2005-01-01

    Radon measurements were carried out in Kozlu, Karadon and Uzülmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m(-3). It is suggested that the ventilation rates should be rearranged to reduce the radon concentration.

  20. 垃圾焚烧灰渣用于二灰碎石路面基层的试验研究%Experiment on Wastes Incineration Residues for Lime-Fly Ash Concrete Pavement Base

    Institute of Scientific and Technical Information of China (English)

    解建光; 陈金东; 曹兴国; 史进舟

    2011-01-01

    By replacing a part of macadam, wastes incineration residues used as aggregates to make lime-fly ash stabilized residues-macadam materials are conducted at nine different proportions. Compaction test , unconfined compressive strength test and shrinkage test are designed to evaluate the pavement performances of the material. Furthermore, the comparative trials are conducted between the new materials and traditional lime-fly ash macadam at the same proportions. Comparing with the traditional lime-fly ash macadam, the maximum dry density decreases by 8. 8% and the optimum water content increases by 38. 4% at the same content of lime and fly ash. Besides, the highest unconf ined compressive strength of lime-fly ash stabilized residues-macadam can reach 1-03 MPa, and the strengths of the new materials are significantly influenced by the content of fly ash. The strength decrease by 21%, if the content of fly ash decreases by 1%. The highest shrinkage coefficient is 67. 2 μ%, and if the content of lime and fly ash decreases by 2.55% the shrinkage coefficient reduces by 3. 1%. The performances of lime-fly ash stabilized residues-macadam can meet the requirements of highway pavement base, and combustion residues can be used as aggregates in road construction.%用城市生活垃圾焚烧灰渣替代部分集料,按照9种不同的配比制备二灰灰渣碎石路面基层材料,进行路用性能试验.结果表明:与普通二灰碎石对比,在相同的二灰含量下,灰渣碎石的最大干密度降低8.8%,而最佳含水量增大38.4%;无侧限抗压强度最高可达1.03 MPa;粉煤灰含量对材料强度影响较为显著,其中粉煤灰含量减少1%,无侧限抗压强度值降低21%;材料的干缩系数最大为67.2μ/%;石灰与粉煤灰含量越低,材料的干缩应变越小,平均干缩系数也越小,当二灰含量减少2.5%,平均干缩系数降低3.1%.二灰灰渣碎石材料满足基层的相关要求,灰渣可以为公路建设提供可持续的集料来源.

  1. 连续配筋混凝土复合式沥青路面层间剪应力及结构%Interlaminar Shear Stress and Structure of Continuously Reinforced Concrete Composite Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    李盛; 刘朝晖; 李宇峙

    2012-01-01

    针对连续配筋混凝土复合式沥青路面(CRC+AC)结构的特点和现有研究的不足,运用传热学理论、力学理论和有限元法,计算和分析了层间剪应力的临界荷位和影响因素;通过室内试验和工程实践,研究了基于层间剪应力的层间结构和材料及CRC层表面处理技术.研究结果表明:层间抗剪强度不足会使CRC+AC结构层间出现纵向和侧向滑移;层间最大剪应力随AC层厚度和模量的增大而减小,且随AC层厚度增加而减小的趋势更为明显,CRC层厚度对层间最大剪应力的影响很小;通过计算分析并结合试验路修筑经验和检测结果,建议CRC+AC结构AC层的厚度不宜小于6cm;建议采用喷洒式结构对CRC+AC结构的层间进行处理,并选用SBS改性沥青作为喷洒沥青,采用裸化技术对CRC层表面进行处理.研究结果可为刚柔复合式沥青路面的合理设计提供重要参考.%Focused on the characteristics and the flaws of existing studies of CRC + AC composite asphalt pavement structure, by using heat transfer theory, mechanics theory and finite element method, the critical * load position and the influencing factors of the interlaminar shear stress were calculated and analyzed. The interlaminar structure and materials, and CRC layer surface treatment technology based on interlaminar shear stress were researched by indoor experiment and engineering practice. The results show that (1) longitudinal and lateral slips would occur in CRC + AC structure due to lacking of interlaminar shear strength; (2 ) the interlaminar maximum shear stress decreases with the thickness and modulus of AC layer, and the decrease trend is more obvious with the increase of thickness of AC layer, the thickness of CRC layer has little effect on the interlaminar maximum shear stress. By analysis and calculating, and combined with measurment and construction experience of test road, it is recommended that the thickness of AC layer should

  2. Field validation of road roughness evaluation using in-pavement strain sensors

    Science.gov (United States)

    Zhang, Z.; Deng, F.; Huang, Y.; Bridgelall, R.

    2016-04-01

    Most transportation agencies now collect pavement roughness data using the inertial profilers, which requires instrumented vehicles and technicians with specialized training to interpret the results. The extensive labor requirements of the profiling activities limit data collection for portions of the national highway system to at most once per year, resulting in outdated roughness data for decision making of maintenance needs. In this paper, a real-time roughness evaluation method was developed by linking the output of durable in-pavement strain sensors to road roughness level. The durable in-pavement sensors will continuously provide information of road roughness in real time after they are installed and calibrated during the road construction until the service life of the associated pavement. Field tests validated the developed strain method by comparison with standard inertial profiling method and the connected-vehicle method. The comparison of the results from the field tests approves the effectiveness of the developed road roughness evaluation method using in-pavement strain sensors, which can be further applied practically for needed concrete pavements.

  3. Comparative study of test methods for bituminized and other low- and medium-level solidified waste materials

    International Nuclear Information System (INIS)

    Various aspects of the behaviour of bituminized or cemented simulated low- or medium-level radioactive waste in contact with water or salt solutions have been investigated. The solubility (approximately 0.5%) and the diffusion coefficient (approximately 5.10-8 cm2/sec) determining transort of water in pure bitumen have been measured for Mexphalte 40/50 at room temperature. A weighing method has been used to study water uptake and swelling of bituminized sodium nitrate, sodium sulphate or cation-exchange resin. The swelling of samples in contact with water was in some cases very pronounced. In strong salt solutions the tendency to swell is much less. The particle size of the embedded waste material is an important parameter. Thermal pre-treatment of cation-exchange resin before bituminization does not seem to improve the quality of the final product. The interaction between bituminized-exchange resin and concrete barrier materials has been studied. Microbial degradation of bitumen and bituminized waste under aerobic conditions has been investigated. It is probably of minor importance as far as leaching is concerned. A method for measuring leaching from a plane surface of cemented waste has been developed. The method avoids the problem of cracks between the sample and the container. Leaching from cemented sodium nitrate or sulphate was investigated. Absorption of CO2 from the atmosphere was found to have only minor effect on Cs- and Na-leaching but gave a pronounced decrease in Ca-leaching. The use of silica-fume as an additive to cemented sodium nitrate decreased the leach rate by a factor 4. (author)

  4. A STUDY OF FATIGUE LIFE OF ASPHALT CONCRETE BASED ON SHUNGITE MINERAL POWDER

    OpenAIRE

    D. I. Chernousov; Vl. P. Podolsky; E. V. Trufanov; B. A. Bondarev

    2011-01-01

    Problem statement. Shortage of mineral powder stimulates seeking of new materials and technologiesby which traditional ones can be replaced without deterioration of their operating properties. Thatis why a study of mineral powder from shungite and development of new technologies of arrangementof high quality and durable asphalt concrete pavement based on shungite is an actual problem.Results. Bearing capacity and service life of asphalt concrete pavement is most completely characterizedby mod...

  5. How Concrete Is Concrete?

    Science.gov (United States)

    Gravemeijer, Koeno

    2011-01-01

    If we want to make something concrete in mathematics education, we are inclined introduce, what we call, "manipulatives", in the form of tactile objects or visual representations. If we want to make something concrete in a everyday-life conversation, we look for an example. In the former, we try to make a concrete model of our own,…

  6. Quantifying Evaporation in a Permeable Pavement System

    Science.gov (United States)

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  7. Dynamic contracting mechanism for pavement maintenance management

    NARCIS (Netherlands)

    Demirel, H.C.; De Ridder, H.A.J.

    2013-01-01

    Technological advances, financial possibilities and changes of demands have increasingly affected the pavement maintenance environment for outsourcing in recent years. This induces complexity in the contracting methods of pavement maintenance activities. Despite the fact that current contracting pra

  8. Deformation Properties and Fatigue of Bituminous Mixtures

    Directory of Open Access Journals (Sweden)

    Frantisek Schlosser

    2013-01-01

    Full Text Available Deformation properties and fatigue performance are important characteristics of asphalt bound materials which are used for construction of pavement layers. Viscoelastic asphalt mixtures are better characterized via dynamic tests. This type of tests allows us to collate materials with regard to axle vibrations which lie usually in the range of 6 Hz–25 Hz for standard conditions. Asphalt modified for heat sensitivity in the range from −20°C to +60°C has significant impact on the overall characteristics of the mixture. Deformation properties are used as inputs for empirical mixture design, and fatigue performance of asphalt mixtures reflects the parameters of functional tests. Master curves convey properties of asphalt mixtures for various conditions and allow us to evaluate them without the need of time expensive testing.

  9. Recycling of asphalt pavements with asphalt rubber

    OpenAIRE

    Pais, Jorge; Pereira, Paulo; Minhoto, Manuel; Baptista, António

    2008-01-01

    Pavement recycling has been an important rehabilitation technique to deal with reclaimed materials from old pavements which are usually sent to landfills. The application of this technique contributes to: i) the accomplishment of the requirements defined by the European legislation for the amount of material sent to landfills; ii) the reduction in the use of new raw materials used to produce pavement layers. The reduction of materials to be used in pavement rehabilitation has also been possib...

  10. Analysis of Instrumentation Selection and Placement to Monitor the Hydrologic Performance of Permeable Pavement Systems and Bioinfiltration Areas at the Edison Environmental Center in New Jersey

    Science.gov (United States)

    In 2009, the U.S. Environmental Protection Agency constructed a 0.4-ha (1-ac) parking lot surfaced with three different permeable pavement types (interlocking concrete pavers, porous concrete, and porous asphalt) and six bioinfiltration areas with three different drainage area to...

  11. The use of reflective and permeable pavements as a potential practice for heat island mitigation and stormwater management

    International Nuclear Information System (INIS)

    To help address the built environmental issues of both heat island and stormwater runoff, strategies that make pavements cooler and permeable have been investigated through measurements and modeling of a set of pavement test sections. The investigation included the hydraulic and thermal performance of the pavements. The permeability results showed that permeable interlocking concrete pavers have the highest permeability (or infiltration rate, ∼0.5 cm s−1). The two permeable asphalt pavements showed the lowest permeability, but still had an infiltration rate of ∼0.1 cm s−1, which is adequate to drain rainwater without generating surface runoff during most typical rain events in central California. An increase in albedo can significantly reduce the daytime high surface temperature in summer. Permeable pavements under wet conditions could give lower surface temperatures than impermeable pavements. The cooling effect highly depends on the availability of moisture near the surface layer and the evaporation rate. The peak cooling effect of watering for the test sections was approximately 15–35 °C on the pavement surface temperature in the early afternoon during summer in central California. The evaporative cooling effect on the pavement surface temperature at 4:00 pm on the third day (25 h after watering) was still 2–7 °C lower compared to that on the second day, without considering the higher air temperature on the third day. A separate and related simulation study performed by UCPRC showed that full depth permeable pavements, if designed properly, can carry both light-duty traffic and certain heavy-duty vehicles while retaining the runoff volume captured from an average California storm event. These preliminarily results indicated the technical feasibility of combined reflective and permeable pavements for addressing the built environment issues related to both heat island mitigation and stormwater runoff management. (letter)

  12. Mechanical properties of hot bituminous mixes manufactured with recycled aggregate of Silestone® waste

    Directory of Open Access Journals (Sweden)

    Rubio, M. C.

    2011-03-01

    Full Text Available This article presents the results of a research project which analyzes the viability of incorporating waste material from decorative quartz solid surfacing in the manufacture of hot bituminous mixes. For this purpose, various bituminous mixes were manufactured with waste aggregate in different percentage. A set of tests were carried out that permitted the characterization of the mechanical behavior of these mixes. The results of these tests were similar to the results obtained when conventional mixes made from virgin quarry aggregate were tested. The results for moisture sensitivity as well as for wheel track rutting on mixes showed the optimal performance of this waste material even under very demanding traffic conditions. Laboratory studies showed that the use of this waste material in the manufacture of bituminous mixes is technically viable and can provide high-quality recycled aggregates at a very low cost, which can be used in the pavement of road.

    Este artículo muestra los resultados de un proyecto de investigación que tiene por objeto analizar la viabilidad de incorporación de residuos procedentes de piedra decorativa en la fabricación de mezclas bituminosas en caliente. Para ello se fabricaron mezclas con áridos reciclados de residuos procedentes de piedra decorativa en distintos porcentajes, realizando un conjunto de ensayos que posibilitaron caracterizar el comportamiento mecánico de dichas mezclas. Los resultados obtenidos fueron similares a los de las mezclas convencionales fabricadas con áridos vírgenes procedentes de cantera. Los valores de resistencia conservada ante la acción del agua y deformación en pista, pusieron de manifiesto la aptitud del residuo incluso ante las condiciones de tráfico más exigentes. Los trabajos realizados en el laboratorio indican que la utilización del residuo en la fabricación de mezclas bituminosas es técnicamente viable, pudiendo obtenerse áridos reciclados de gran calidad y

  13. 基于土工合成材料加铺层的沥青混凝土路面抗裂性能%Crack Resistance of Geosynthetics Overlay Based Asphalt Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    孙雅珍; 刘杰民; 赵复笑

    2012-01-01

    应用数值计算的方法和冲击韧性试验研究在行车载荷作用下土工合成材料加铺层对含反射裂缝沥青混凝土路面的抗裂效果,并对土工合成材料弹性模量进行了优化设计.分析了温度、时间和加铺层弹性模量对裂缝延长线上各点正应力和面层层底拉应力的影响;应用冲击韧性试验系统评价了土工合成材料加铺层的抗裂效果.数值计算与冲击韧性试验结果基本一致.研究结果表明:铺设土工合成材料是防治反射裂缝的有效途径,能有效地改变结构的应力分布,更大程度地减少了应力集中;同时确定最佳的土工布加铺层的弹性模量为1 000 MPa;但加铺层对含裂缝沥青混凝土路面的路表弯沉基本没有影响.%The effect of geosynthetics overlay on retarding propagation of reflective cracks in AC pavement under vehicle load was studied by numerical calculation and impact toughness test, and the modulus of geosynthetics overlay was optimized. The effects of temperature, time and elastic modulus of the geosynthetics overlay on the tensile stress at the bottom of surface course and the normal stresses on the line of extensional crack-tip were analyzed. The impact toughness test was conducted to evaluate the effectiveness of the crack resistance of the geosynthetics overlay. The numerical calculation result was consistency with the test result. The results show that (1) geosynthetics overlay is effective for reflective crack resistance, it could obviously decrease stress concentration and change stress distribution; (2 ) the elastic modulus of the optimum geosynthetics overlay is 1 000 Mpa; (3) the geosynthetics overlay basically has no effect on the vertical deflection of the road surface.

  14. The Albedo of Pervious Cement Concrete Linearly Decreases with Porosity

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2015-01-01

    Full Text Available Pervious pavements have been advocated as a potential countermeasure to the urban heat island effect. To understand if pervious pavements stay cooler than conventional pavements, the albedo of the pervious concrete must be understood. This study measured the albedo of pervious concrete with different porosity. Four Portland cement concrete mixes were casted, using designed amounts of sand to vary the porosity of the pervious concrete samples. The samples were sliced and the spectral reflectance and albedo of the sliced samples were measured and analyzed. It is found that the albedo of pervious concrete decreases linearly with the increase of the porosity. The albedo of a pervious Portland concrete varies from 0.25 to 0.35, which is 0.05~0.15 lower than the albedo of conventional cement concrete. Due to this lower albedo, it should be cautious to develop pervious concrete to battle with urban heat island unless the evaporation of pervious concrete is promoted to compensate the additional solar absorption caused by the low albedo.

  15. Development of non-standard equipment of bituminization line

    International Nuclear Information System (INIS)

    A brief description is presented of some components of the bituminization line developed at the Research Institute of Chemical Installations in Brno. The film rotor evaporator has an evaporation area of 2 m2. The mixing tank is the main technological assembly for processing loose materials, i.e., sorbents and fly ash which it mixes with melted bitumen. The screw conveyor with a three-way valve is designed for batching the dried radioactive sorbent and fly ash into mixing tanks. Attention is also devoted to certain systems of measurement and control of the bituminization line, namely to measurement of the level of the bituminization product, the flow rate of bituminization emulsion and the water-sorbent mixture and to the diagnostics of failure and accident conditions of the film rotor evaporator. (Z.M.)

  16. EXPERIMENTAL STUDY ON HORIZONTAL COMBUSTION TECHNIQUE FOR BITUMINOUS COAL BRIQUET

    Institute of Scientific and Technical Information of China (English)

    路春美; 程世庆; 邵延玲; 张晔

    1997-01-01

    Through a lot of experiments, a new kind of stove using horizontal combustion technique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminous coal briquet, distribution of temperature field in the stove, the regularities of evolution and combustion of volatile matter, the burning rate and efficiency of bituminous coal briquet, characteristics of fire-sealing and sulfur-retention. The results show that, with the technique, some achievements can be obtained in combustion of bituminous coal briquet, such as lower pollution that the flue gas black degree is below 0.5R and dust concentration is below 90mg/m3 . The stove's combustion efficiency reaches 90%, sulfur fixing efficiency is 60%, and CO concentration is decreased by 40% compared with other traditional stoves. With so many advantages, the stove can be used extensively in civil stoves and smaller industrial boilers.

  17. Bituminous and asphaltic membranes for radioactive waste repositories on land

    International Nuclear Information System (INIS)

    The aim of the study has been to identify, within generic designs for waste facilities, areas where bituminous materials might be incorporated as a barrier. The report is presented in three sections: Part I - The properties of bitumen are described, with particular reference to the long-term behaviour of the material. The durability of bitumen is discussed, including aspects such as ageing, microbial degradation, chemical resistance and radiation resistance. Part II -The use of bituminous materials in hydraulic engineering is outlined. Much of this section of the report concentrates on the use of bituminous materials in embankment dams and reservoir construction. A review of material technology and construction techniques is presented and a detailed assessment made of the performance of the materials in service. Part III - Generic trench type radioactive waste repository designs incorporating bituminous materials are presented. Material and construction specifications for the designs are detailed, and a performance assessment presented. (author)

  18. Mechanical behavior of flexible pavements undergoing thermal gradients - doi: 10.4025/actascitechnol.v33i3.10848

    Directory of Open Access Journals (Sweden)

    Grazielli Vassoler

    2011-07-01

    Full Text Available The proper structural understanding of a pavement should consider, according to the pavement mechanics, the aspects related to the traffic load, the environment and material properties. When asphaltic materials are used, the stress/strain relationships and the dependencies of load-time and temperature are key parameters for understanding flexible pavement performance. In this study, we employed the finite elements method to calculate stress/strain in flexible pavements structures considering temperature variation. The input data includes material stiffness, which is function of temperature and changes with position and time. The pavement temperature is obtained through the heat transfer differential equation, applying the Laplace transform and its numerical inversion. The finite elements grid was generated by the software ANSYS® and imported by the software MATLAB®. In order to determine the stiffness of the first layer (asphalt concrete we used the average of four nodes, depending on the each node temperature. The result evidences the importance of thermal gradients for the pavement analysis, both for the fatigue cracking and the accumulation of plastic deformations. The use of unique modulus for asphalt concrete layer generates results far from reality.

  19. Effects of bituminous layer as backfill material on mechanical behavior in tunnel model

    OpenAIRE

    Moriyoshi, Akihiro; Takano, Shin-ei; Urata, Hiroyuki; Suzuki, Tetsuya; Yoshida, Takaki

    2001-01-01

    This paper describes the effects of bituminous material as a backfill material on mechanical behavior in model tunnel in laboratory. It is known that load spreading and relaxation of bituminous material are good properties. Then if we use bituminous material as a backfill material of tunnel, the tunnel will have waterproof, good load spreading property. We used new bituminous material (Aquaphalt) which can solidify in water. We conducted relaxation test in tension for new bituminous mat...

  20. 沥青路面冷再生技术在路面维修中的应用%Application of Cold Recycling Technology of Asphalt Pavement in the Pavement Repair

    Institute of Scientific and Technical Information of China (English)

    冯国龙

    2014-01-01

    This paper analyzed several main causes of the damage of asphalt pavement and simply introduced the main techniques of the cold recycling technology of asphalt pave-ment. The author also introduced the concrete applying meth-ods of the cold regeneration technique of asphalt pavement in pavement repair.%本文针对沥青路面出现损坏的几个主要原因进行了分析,简单介绍了沥青路面冷再生技术的主要工艺,并且介绍了沥青路面冷再生技术在路面维修中的具体使用方法。

  1. Theoretical and experimental study on tension-deformation mechanical properties of continuously reinforced concrete approach pavement of FJSBs%全无缝桥梁接线路面拉伸力学特性理论和实验研究

    Institute of Scientific and Technical Information of China (English)

    马永春; 邵旭东; 梁才

    2012-01-01

    Because the elastoplascic tension character of the Continuously Reinforced Concrete Approach Pavement (CRCAP) is sensitive to the seismic response of the Fully Jointless Semi-integral Bridges (FJSBs) , a macro elasto-plastic tension-deformation theoretical model (P ?A model) of CRCAP was developed from the uniaxial tensile average stress-strain constitutive model of the steel bar and concrete and a tensile test was carried out by using a full scale experimental model of CRCAP with a length of 28m. Results show that; the theoretical skeleton curve is in good agreement with the tested curve, whatever the steel bar is pre-yield or post-yield and the CRCAP is still not broken when its tensile deformation reaches up to 14 cm. Conclusion is that the theoretical skeleton P - A model can be used for the seismic design and the damage assessment of FJSBs and the high ductility of the CRCAP is helpful for the FJSBs to resist strong earthquakes.%为了掌握和模拟全无缝桥梁接线路面弹塑性拉伸特性,本文基于钢筋和混凝土的单轴拉伸平均应力-应变本构模型,推导出接线路面的宏观弹塑性拉伸P-△理论模型;并对室内总长28 m的接线路面足尺模型,进行了拉伸试验.结果显示:(1)接线路面的理论与实验拉伸P-△骨架曲线在钢筋屈服前后都吻合得很好,可以直接用于全无缝桥梁抗震设计和损伤评估;(2)接线路面实验模型的拉伸变形量△高达14 cm时,仍未拉断,其延性甚好、有利于抗震.

  2. RESEARCH ON THE HIGH PERFORMANCE COMPOSITE ROAD CONCRETE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Ordinary concrete presents short service life when used for building and repairing high-grade road with heavy traffic due to its large brittleness, poor bending flexibility and serious shrinkage on drying. In this paper,a new kind of high performance concrete has been designed by means of combination of organic, inorganic material as well as metal material.The research and application have shown that this new concrete can significantly counteract the deficiency of ordinary concrete and give excellent mechanical properties and pavement performances. The application of this new kind of concrete is of great social and economic significance.

  3. The bituminous sands : a Canadian mirage?

    Energy Technology Data Exchange (ETDEWEB)

    Rousse, D.R. [Quebec Univ., Chicoutimi, PQ (Canada). Dept. des Sciences Appliquees; Nasr, G.J. [Lebanese Univ., Roumieh (Lebanon). Faculty of Engineering; Turcotte, S.F. [Quebec Univ., Montreal, PQ (Canada). Centre d' Etudes Internationales et Mondialisation; Salah, N.B. [Ecole Superieure des Sciences et Techniques De Tunis, Tunis (Tunisia). LMMP

    2009-07-01

    This paper examined the controversy about the potential role of a significant increase in Canadian oil sands production in order to bridge the upcoming gap between the world's increasing energy demand and the total recoverable oil supply. The paper presented the actual potential of different scenarios and considered the prediction cost forecasts. A brief overview of environmental impacts and the real return on investments were also provided. Environmental impacts that were considered included land degradation; water contamination; ecosystem damage; and air pollution. Nuclear energy was also presented as a possible solution. The paper demonstrated that even in a very optimistic scenario, Canada's oil sands accelerated production has a negligible effect on the aforementioned gap, has a considerable impact on environment that has yet to be accounted for. Energy ratios that were presented included energy return on energy investment; energy available on energy used; and energy payback. It was concluded that enhanced recovery techniques are clearly needed for future sustainable exploitation of these bituminous sands. 32 refs., 1 fig.

  4. Development of an accelerated pavement test reproducing the effect of natural ageing on skid resistance

    OpenAIRE

    Kane, M.; D. Zhao; Chailleux, E.; Delarrard, F.; Do, M. T.

    2013-01-01

    This study deals with the development of a new test method simulating the effect of ageing on skid resistance. This test is applied to bituminous mixes in this study, but can also be applied to concrete. This test relies on two machines, the Wehner–Schulze machine, to measure the friction, and the Weatherometer sunset machine, to simulate weather effects (rain, wind, sunlight, etc.). The relevance of this test is evaluated from comparisons between changes in friction and a chemical func...

  5. Analysis and modeling of 3D complex modulus tests on hot and warm bituminous mixtures

    Science.gov (United States)

    Pham, Nguyen Hoang; Sauzéat, Cédric; Di Benedetto, Hervé; González-León, Juan A.; Barreto, Gilles; Nicolaï, Aurélia; Jakubowski, Marc

    2015-05-01

    This paper presents the results of laboratory testing of hot and warm bituminous mixtures containing Reclaimed Asphalt Pavement (RAP). Complex modulus measurements, using the tension-compression test on cylindrical specimens, were conducted to determine linear viscoelastic (LVE) behavior. Sinusoidal cyclic loadings, with strain amplitude of approximately 50ṡ10-6, were applied at several temperatures (from -25 to +45 °C) and frequencies (from 0.03 Hz to 10 Hz). In addition to axial stresses and strains, radial strains were also measured. The complex modulus E ∗ and complex Poisson's ratios ν ∗ were then obtained in two perpendicular directions. Measured values in these two directions do not indicate anisotropy on Poisson's ratio. The time-temperature superposition principle (TTSP) was verified with good approximation in one-dimensional (1D) and three-dimensional (3D) conditions for the same values of shift factor. Experimental results were modeled using the 2S2P1D model previously developed at the University of Lyon/ENTPE. In addition, specific analysis showed that eventual damage created during complex modulus test is very small and is equivalent to the effect of an increase of temperature of about 0.25 °C.

  6. 3-D cohesive finite element model for application in structural analysis of heavy duty composite pavements

    DEFF Research Database (Denmark)

    Skar, Asmus; Poulsen, Peter Noe

    2015-01-01

    The problem of stiffness degradation in composite pavement systems from localised fracture damage in the quasibrittle cement bound granular mixture are today taken into account only by empirical formulas. These formulas deals with a limited number of materials in a restricted range of design...... this paper presents a numerical analysis of the fracture behaviour of cement bound granular mixtures in composite concrete block pavement systems applying a cohesive model. The functionality of the proposed model is compared to experimental investigations of beam bending tests. The pavement is modelled...... as a slab on grade and parameters influencing the response such as geometry, material parameters and loading position are studied and compared to experimental results. It is found that a cohesive model is suitable for the description of the fracture behaviour of cement bound granular mixtures. Moreover...

  7. Plastic Damage Model to Evaluate the Fracture Size of Semi-Rigid Base Pavement

    Directory of Open Access Journals (Sweden)

    Cao Peng

    2013-01-01

    Full Text Available A simple supported beam model has been presented to simulate the response of semi-rigid pavement structure, which are consistent of the upper layer, middle layer, bottom layer, base and sub base course, during the cycle vehicle loading. This mechanics model coupled with plastic-damage mechanics model could simulate the limit broken of the pavement structure in condition that soil base layer losing bearing capacity gradually. In the meanwhile, numerical calculations based on preceding mechanics model, using the FEM software ABAQUS, have been used to define the broken size of beam. The results indicated that: when the size of simple supported beam expanded to 10 m, brittle damage could happen immediately, Just the standard vehicle loading (about 0.7 Mpa has been implement once. Objective of this study is to provide a physical and rather concrete explanation for the style and concept of the semi-rigid pavement brittle broken.

  8. Teaching Methodology of Flexible Pavement Materials and Pavement Systems

    Science.gov (United States)

    Mehta, Yusuf; Najafi, Fazil

    2004-01-01

    Flexible pavement materials exhibit complex mechanical behavior, in the sense, that they not only show stress and temperature dependency but also are sensitive to moisture conditions. This complex behavior presents a great challenge to the faculty in bringing across the level of complexity and providing the concepts needed to understand them. The…

  9. 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.

  10. 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.

  11. 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.

  12. Compatibility between a quartz surface hardener and different base concrete mixtures

    OpenAIRE

    Pinheiro-Alves, M.ª Teresa; Fernandes, André; Bettencourt Ribeiro, António

    2012-01-01

    Many cases of cracking and detachment of the concrete surface have appeared in concrete floors, namely pavements where surface hardeners were used, especially in car parks, industrial areas and warehouses. This paper studies the behaviour of ten different base concretes mixtures made with two chemical admixtures and four additions, when a quartz surface hardener is applied. The objective is to identify the relevant parameters of the concrete constituents that influence the open time. Results ...

  13. Compatibility between base concrete made with different chemical admixtures and surface hardener

    OpenAIRE

    Pinheiro-Alves, M.ª Teresa; Sequeira, Ana Rita; Bettencourt Ribeiro, António

    2012-01-01

    Many cases of cracking and detachment of the concrete surface have appeared in concrete floors where surface hardeners were used in Portugal. The main causes for cracking and delamination of trowelled concrete pavements are several and it is essential to control bleeding and the time available to perform the finishing operations. Several base concretes were made with different chemical admixtures and one type of surface hardeners. The purpose of this study was evaluating the influence of the ...

  14. TECHNOLOGY OF DISPERSED REINFORCEMENT OF ASPHALT CONCRETE MIXTURES WITH CHRYSOTILE FIBRES

    OpenAIRE

    S. I. Buldakov; A. Yu. Dedyukhin

    2010-01-01

    Problem statement. The issues of technology of preparation of dispersed rein-forced asphalt concrete mixtures are still not clearly understood. Available tech-nologies of dispersed reinforcement involve application of granulated additives, which permits the quality of asphalt concrete mixtures to be improved and, there-fore, it will result in increasing life expectancy of asphalt concrete pavements.Results and conclusions. The ways of improvement of quality and durability of asphalt-concrete ...

  15. DYNAMIC JOINT LOAD TRANSFER EFFICIENCY OF RIGID PAVEMENT

    Directory of Open Access Journals (Sweden)

    YU Xinhua

    2011-02-01

    Full Text Available the mechanistic analysis presented in this paper is only the beginning of new approach for understanding the real joint load transfer capability on airport and highway concrete pavements. It gives up the two major assumptions those have been popularly adopted by hundreds of published papers: the load is transferred under a wheel with zero speed and with fixed position. The real load transfer in field is always under wheels with non-zero speed and with varied position at any moment. The objective of this study focuses on quantifying the dynamic effects of a moving wheel while it is crossing a joint on a pavement. The analysis is conducted using a model of two-slab system on Kelvin foundation under a moving wheel with variable speed v, different pavement damping Cs, foundation reaction modulus k and foundation damping Ck. The dynamic joint load transfer efficiency is temporarily and empirically defined by the peak strain ratio LTE(S on the two sides of a joint. The primary findings include: (1 The higher speed of a moving wheel leads to the higher LTE(S;(2 The larger the pavement damping Cs leads to the higher LTE(S;(3 The numerical ratio c(=LTE(Sdynamic/ LTE(Sstatic varies in the range 1 to 2 mainly depending on speed v and damping Cs;(4 The LTE(Sdynamic is not sensitive to foundation reaction modulus k and foundation damping Ck. Further researches are needed for appropriate applications of the new model in practice.

  16. Utilization of Electronic Waste Plastic in Concrete

    Directory of Open Access Journals (Sweden)

    Vivek S. Damal

    2015-04-01

    Full Text Available In India, bitumen pavements are commonly used for highways. Due to the increasing traffic intensity, distress such as rutting and cracking of pavements are very common in Indian roads. Under varying seasonal temperature, flexible pavements tend to become soft in summer and brittle in winter. Investigations revealed that properties of concrete can be better than bitumen roads. But now a day‟s concrete roads are used commonly because concrete roads have more life span than the bitumen roads. In large cities now a day‟s concrete roads are used because concrete roads are more durable, strengthen and having more life span than bitumen roads. Waste plastics and E-waste (electronic waste both by domestic and industrial sectors can be used in the production of asphalt mix. Waste plastic, mainly used for packing are made up of polyethylene, polypropylene, polystyrene. Electronic waste, abbreviated as e-waste, consists of discarded old computers, TVs, refrigerators; radios, etc are basically any electrical or electronic appliance that has reached its end of life. An experimental study is made on the utilization of E-waste particles as fine aggregates in concrete with a percentage replacement ranging from 0 % to 21.5% i.e. (7.5%, 15% and 21.5% on the strength criteria of M30 Concrete. Compressive strength Concrete with and without E- waste plastic as aggregates was observed which exhibits a good strength. The feasibility of utilizing E-waste plastic particles as partial replacement of fine aggregate has been presented. In the present study, compressive strength was investigated for Optimum Cement Content and 7.5% E-plastic content in mix yielded stability and very good in compressive strength of 43 grade cement.

  17. Tuning in to pavement radio

    NARCIS (Netherlands)

    Ellis, S.D.K.

    1989-01-01

    This article describes a phenomenon known all over Africa, for which there is no really satisfactory term in English but which is summed up in the French term 'radio trottoir', literally 'pavement radio'. It may be defined as the popular and unofficial discussion of current affairs in Africa, partic

  18. Influence of mixture composition on the noise and frictional characteristics of flexible pavements

    Science.gov (United States)

    Kowalski, Karol J.

    Both traffic noise and wet pavement-tire friction are mainly affected by the tire/pavement interaction. Existing laboratory test methods allow for evaluation of polishing resistance of the aggregates only. Currently, there is no generally accepted standardized laboratory test method to address noise related issues and the overall frictional properties of pavements (including macrotexture). In this research, which included both laboratory and field components, friction and noise properties of the flexible (asphalt) pavements were investigated. As a part of this study, a laboratory device to polish asphalt specimens was developed and the procedure to evaluate mixture frictional properties was proposed. Following this procedure, forty-six different Superpave mixtures (each utilizing a different aggregate blends), one stone matrix asphalt (SMA) mixture and one porous friction course (PFC) mixture were tested. Six of the above mixes (four Superpave mixtures, SMA mixture and PFC mixture) were selected for laboratory noise testing. This testing was performed using a one-of-a-kind tester called the Tire/Pavement Test Apparatus (TPTA). In addition, the field sections constructed using Superpave, SMA and PFC mixtures were also periodically tested for friction and noise. Field measurements included testing of total of 23 different asphalt and two concrete pavements. The field friction testing was performed using both portable CTM and DFT devices and the (ASTM E 274) locked wheel friction trailer. The laboratory friction testing was performed using CTM and DFT devices only. The results of both field and laboratory friction measurements were used to develop an International Friction Index (IFI)-based frictional requirement for laboratory friction measurements. The results collected in the course of the study indicate that the IFI-based flag values could be successfully used in place of SN-based flag values to characterize frictional characteristics of pavements.

  19. CONCRETE DURABILITY Through High Volume Fly ash Concrete (HVFC A Literature review

    Directory of Open Access Journals (Sweden)

    VANITA AGGARWAL

    2010-09-01

    Full Text Available The application of concrete in construction is as old as the days of Greek and roman civilization. But for numerous easons, the concrete construction industry is not sustainable. It consumes a lot of virgin materials and the principal raw material of concrete i.e. cement is responsible for green house gas emissions causing a threat to environment through global warming. Therefore, the industry has seen various types of concrete in search of a solution to sustainable development. Infrastructural growth has witnessed many forms of concrete like High Strength Concrete, High Performance Concrete, Self Compacting Concrete and the latest in the series is High Volume Fly Ash Concrete (HVFC. The paradigm has shifted from one property to other of concrete with advancement in technology. The construction techniques have been modernized with focus on high strength, dense and uniform surface texture, more reliable quality, improved durability and faster construction. This paper discusses the development of high volume fly ash concrete for construction with reference to its predecessors like HSC and HPC. The literature available on use of fly ash in concrete has been extensively searched for getting a platform for the start of research on use of high volumes of fly ash in concrete pavements.

  20. State-of-the-art review of the applications of nanotechnology in pavement materials

    Science.gov (United States)

    Castillo, Luis, Jr.

    The use of nanotechnology in pavement materials is one main area that shows great promise and has the potential to change commonly used materials. This will develop more effective solutions to achieve the desired performance. The overall objective of this work is to present a state-of-the-art literature review of nano-science-based principles to improve the performance and, ultimately, the life cycle of transportation construction materials. This work will be organized into two different parts. The first part will consist of six sections: applications of nanotechnology in concrete pavements, applications of nanotechnology in asphalt pavement, application of nanotechnology in general soils, cost-benefit analysis, challenges, and trends to the future. In addition, a current practice review was performed from a literature review that included a questionnaire of the knowledge and opinion about nanotechnology, which included students, general contractors, teachers, engineers, and architects. The second part will deal with the advancement of the application of nanotechnology in pavement materials for different developed countries. Because nanotechnology is relatively a young field in pavement materials, limited research has been conducted in North America, Europe, and Asia. A comparison of the advancement of nano-science-based principles, as applied to the performance and life cycle of transportation materials, for the three continents will be carried out in a summarized manner.

  1. Application of viscoelastic continuum damage approach to predict fatigue performance of Binzhou perpetual pavements

    Directory of Open Access Journals (Sweden)

    Wei Cao

    2016-04-01

    Full Text Available For this study, the Binzhou perpetual pavement test sections constructed in Shandong Province, China, were simulated for long-term fatigue performance using the layered viscoelastic pavement analysis for critical distresses (LVECD finite element software package. In this framework, asphalt concrete was treated in the context of linear viscoelastic continuum damage theory. A recently developed unified fatigue failure criterion that defined the boundaries of the applicable region of the theory was also incorporated. The mechanistic modeling of the fatigue mechanisms was able to accommodate the complex temperature variations and loading conditions of the field pavements in a rigorous manner. All of the material models were conveniently characterized by dynamic modulus tests and direct tension cyclic fatigue tests in the laboratory using cylindrical specimens. By comparing the obtained damage characteristic curves and failure criteria, it is found that mixtures with small aggregate particle sizes, a dense gradation, and modified asphalt binder tended to exhibit the best fatigue resistance at the material level. The 15-year finite element structural simulation results for all the test sections indicate that fatigue performance has a strong dependence on the thickness of the asphalt pavements. Based on the predicted location and severity of the fatigue damage, it is recommended that Sections 1 and 3 of the Binzhou test sections be employed for perpetual pavement design.

  2. Bituminization of low- and intermediate-level radioactive concentrates

    International Nuclear Information System (INIS)

    The results and experiences are summed up from the research and development of the technology of bituminization of low- and intermediate-level radioactive concentrates generated in the operation of nuclear power plants with WWER-440 reactors. The experiments took place on a pilot plant bituminization line with various model solutions at an evaporator capacity of 70, 100 and 140 litres per hour. The composition of the solutions changed in dependence on the knowledge of the composition of actual concentrates in the V-1 nuclear power plant at Jaslovske Bohunice. The following factors were studied in the concentrate: the effect of its pH, its borate content and content of metal carbonates, the content of organic acid salts, the content of detergents, etc., on the process of bituminization. Physico-chemical conditions are described under which the operation of the evaporator was fail-safe and filling of the bituminization product with salts homogeneous. A low water content of up to 1% was achieved. The properties of the bituminization product were negatively affected by a high level of heavy metal oxides, surfactants, oxalates and citrates. In order to improve the properties of the product it will be necessary to replace bitumen emulsion Silembit-60 used as reinforcement matrix, by a different type of bitumen. (Z.M.)

  3. Simplified Pavement Design for LPAs: Introduction to PaveXpress

    OpenAIRE

    Bonte, Dudley

    2015-01-01

    Simplified Pavement Design for LPA's; An introduction to and use of PaveXpress, a simplified, free, web-based pavement design scoping tool for roadway and parking lot pavements. The system was developed by Pavia Systems in partnership with the National Asphalt Pavement Association. PaveXpress creates technical sound pavement structural designs for flexible and rigid pavements based on widely accepted industry standards from the Association of State Highway Officials (AASHTO). The simplified p...

  4. Examples of cooler reflective streets for urban heat-island mitigation : Portland cement concrete and chip seals

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, M.; Akbari, H.; Chang, S.-C.; Levinson, R.; Pon, B.

    2003-04-30

    Part of the urban heat island effect can be attributed to dark pavements that are commonly used on streets and parking lots. In this paper we consider two light colored, hence cooler, alternative paving materials that are in actual use in cities today. These are Portland cement concrete (PCC) pavements and chip seals. We report measurements of the albedos of some PCC and chip sealed pavements in the San Francisco Bay Area. The albedos of the PCC pavements ranged from about 0.18 to 0.35. The temperatures of some PCC pavements are also measured and calculated. We then consider how the albedos of the constituent materials of the PCC (stone, sand and cement) contribute to the albedos of the resulting finished concrete. The albedos of a set of chip sealed pavements in San Jose, CA, were measured and correlated with the times of their placement. It is found that the albedos decrease with age (and use) but remain higher than that of standard asphalt concrete (AC) for about five years. After t hat, the albedos of the chip seals are about 0.12, similar to aged AC. The fact that many PCC pavements have albedos at least twice as high as aged AC suggests that it is possible to have pavement albedos that remain high for many years.

  5. Compressive Strength and Water Absorption of Pervious Concrete that Using the Fragments of Ceramics and Roof Tiles

    OpenAIRE

    Prahara E.; Meilani

    2014-01-01

    Pervious concrete was introduced in America in 2003, popularized by Dan Brown and used as a rigid pavement in the open parking lot. Rigid pavement using pervious concrete can absorb water in the surface to go straight through the concrete to the ground below.This water flow is one of the benefit of using the pervious concrete. Using of wastes such as broken roof and ceramics tiles are not commonly used in Indonesia. Utilization these kind of wastes is predicted lower the compressive strength ...

  6. Conductive concrete wins Popular Science prize

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1997-06-01

    A conductive concrete developed by a research team at IRC (Institute for Research in Construction, National Research Council of Canada) has won a prize in the home technology category because of its possible use in heating homes. Following the award, there have been a number of inquiries regarding possible applications for the concrete. Greatest interests in the concrete have been in its potential to heat buildings by using it as flooring. Other possible applications included de-icing pavements to building warming pads for parking aircraft. Essentially, carbon fibres and conductive particles are added to a concrete mix in such a quantity that they form a network within the mix, ensuring high electrical conductivity. A demonstration project is underway to build a 20 by 80 foot conductive concrete pad to test the material`s capability as a snow removal and de-icing tool.

  7. Pavement Preservation for Elected Officials: The Inside Story of Pavement Deterioration

    OpenAIRE

    Olson, Jim

    2012-01-01

    This session is intended to provide elected officials and practitioners with an introduction to the concept of pavement preservation and its applicability within public agencies. Topics include definitions, budget planning, pavement life, road networks, alternative strategies, pavement distresses, guidelines and preservation treatments.

  8. Impact of Overweight Traffic on Pavement Life Using Weigh-In-Motion Data and Mechanistic-Empirical Pavement Analysis

    OpenAIRE

    Wang, Hao; Zhao, Jingnan; Wang, Zilong

    2015-01-01

    The objective of this study is to evaluate the impact of overweight traffic on pavement life using mechanistic-empirical analysis approach. The state-of-practice mechanistic-empirical pavement design and analysis software (Pavement-ME) was used to predict pavement life under different traffic loading scenarios. Field performance data at the sites where the WIM data were collected were analyzed to estimate the pavement service life at field condition. The pavement structures considered in the ...

  9. How Concrete is Concrete

    Directory of Open Access Journals (Sweden)

    Koeno Gravemeijer

    2010-07-01

    Full Text Available If we want to make something concrete in mathematics education, we are inclined introduce, what we call, ‘manipulatives’, in the form of tactile objects or visual representations. If we want to make something concrete in a everyday-life conversation, we look for an example. In the former, we try to make a concrete model of our own, abstract, knowledge; in the latter, we try to find an example that the others will be familiar with. This article first looks at the tension between these two different ways of making things concrete. Next another role of manipulatives, will be discussed, namely that of means for scaffolding and communication. In this role, manipulatives may function as means of support in a process that aims at helping students to build on their own thinking while constructing more sophisticated mathematics

  10. Long Life Pavements; Firmes de larga duracion

    Energy Technology Data Exchange (ETDEWEB)

    Mateos Moreno, A.; Marron Fernandez, J. O.; Perez Ayuso, J.

    2009-07-01

    The existence of long-life pavements is not new; they have been built in Europe and the United States for decades. In fact, the concept arises from the observation of in-service roads; it was verified how particular pavements, initially designed for a 20-year service life, did not seem to have reduced the bearing capacity along the time, and its maintenance necessities had been exclusively focused on the wearing course. The base idea of long-life pavements is the existence of a fatigue threshold below which the damage produced by each load application is, in practice, zero or below the healing potential of the asphalt mix. The use practice of long-life pavements design considers a pavements constituted by three asphalt layers, each one with a very specific role: a wearing course that provides with the surface characteristics, an intermediate course that provides with most of the structural capacity and a base course that provides with the fatigue resistance. Furthermore, one of the particularities is the design against specific distress mechanisms. Maintenance strategy also presents specific particularities for long-life pavements. It is essentially focused on the detection of surface deterioration, and the appropriate and timely repair, before the damage extends beyond the wearing course, putting into risk the structural integrity of the pavement. Nowadays, this new way to conceive the design, the construction and the maintenance of road pavements, constitutes one of the main challenges for pavement engineering worldwide. (Author) 5 refs.

  11. Flexible pavement performance evaluation using deflection criteria

    Science.gov (United States)

    Wedner, R. J.

    1980-04-01

    Flexible pavement projects in Nebraska were monitored for dynamic deflections, roughness, and distress for six consecutive years. Present surface conditions were characterized and data for evaluating rehabilitation needs, including amount of overlay, were provided. Data were evaluated and factors were isolated for determining the structural adequacy of flexible pavements, evaluating existing pavement strength and soil subgrade conditions, and determining overlay thickness requirements. Terms for evaluating structural condition for pavement sufficiently ratings were developed and existing soil support value and subgrade strength province maps were evaluated.

  12. Structural Evaluation for Maputo Airport Pavement

    Institute of Scientific and Technical Information of China (English)

    Jose F.R.Diogo; LU Yang; ZHANG Hua

    2007-01-01

    Maputo Airport was initially constructed to serve mixed traffic of light and medium aircrafts. With its opening to heavier aircrafts such as B727, DC10, Airbus 340, etc. , structural improvements have become necessary. For this purpose, structural evaluation were described and performed using falling weight deflectometer. Results show that while subgrade response to loads appears more consistent with depth, surface layer of the pavement is significantly influenced by the layer thickness as well as mechanical properties of pavement materials. Load magnitude also affects pavement performance. But loading conditions show an equivalent or even greater influence on pavement performance.

  13. Toward Development of Self-Compacting No-Slump Concrete Mixtures

    OpenAIRE

    Hoornahad, H.

    2014-01-01

    No-slump concrete (NSLC) is one of the commercial types of concrete that is known as a type of concrete with almost zero flowability. No-slump concrete is normally used for typical applications, like pavements construction and massive dam structures. The specific feature of a no-slump concrete is its high shape holding ability. No fixed formwork is required for the construction. The main disadvantage of this type of concrete is that a great amount of energy is required for a proper compaction...

  14. Measurement of heat generation from simulated bituminized product

    International Nuclear Information System (INIS)

    The fire and explosion incident occurred at Bituminization Demonstration Facility of PNC Tokai Works on March 11, 1997. In order to ascertain the cause of incident, the investigation has been pushed forward. For the investigation, we prepared simulated bituminized product of measurement of heat generation in low temperature region less than 200degC. We used calvet Calorimeter MS80 for the heat generation measurement. Result of measurement, we were able to catch the feeble heat generation from bituminized product. The maximum calorific value that was able to detect it in isothermal measurement was approximately 1 mW/g in 160degC. It was approximately 2 mW/g in 200degC. And, as the another measurement, the measurement condition went heat rate by 0.01degC/minute, the highest temperature 190degC. As a result, the maximum generation of heat value that was able to detect it was approximately 0.5 mW/g. I changed simulated bituminized products and measured these. A difference of condition is salt particle size, salt content rate (45%, 60%), addition of the simulated precipitate. But there was not a difference in the generation of heat characteristic detected. (author)

  15. 30 CFR 716.4 - Special bituminous coal mines.

    Science.gov (United States)

    2010-07-01

    ... INTERIOR INITIAL PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.4 Special bituminous coal mines... may be used if necessary to prevent erosion. (3) Spoil piles will be graded and contoured with no more... of an amendment or revision to the State of Wyoming's regulatory program, regulations, or...

  16. 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

  17. The effect of Cryogenic Crumb Rubber in cold recycled mixes for road pavements

    DEFF Research Database (Denmark)

    Pettinari, Matteo; Dondi, Giulio; Sangiorgi, Cesare;

    2014-01-01

    Over recent years, the necessity of reducing the environmental mpact of building new infrastructures has increasingly directed research toward developing innovative manufacturing methods and materials that can satisfy these objectives. Cold recycling, widely used in renovating road pavements...... in Italy, is also moving in this direction, lowering the manufacturing temperatures of bituminous mixes and reducing or ultimately eliminating the use of virgin raw materials. Currently, a wide range of materials are used and, consequently, the number of variables to be considered in the mix-design process...... of cold recycled mixes for road bases is considerable. Furthermore, new products are continuously being introduced or developed for recycling purposes. The objective of this research project was to test the effects, both mechanically and environmentally, of crumb rubber included in 100% Reclaimed Asphalt...

  18. Modelling Flexible Pavement Response and Performance

    DEFF Research Database (Denmark)

    Ullidtz, Per

    This textbook is primarily concerned with models for predicting the future condition of flexible pavements, as a function of traffic loading, climate, materials, etc., using analytical-empirical methods.......This textbook is primarily concerned with models for predicting the future condition of flexible pavements, as a function of traffic loading, climate, materials, etc., using analytical-empirical methods....

  19. Numerical Simulation of Tire-Pavement Interaction

    NARCIS (Netherlands)

    Srirangam, S.K.

    2015-01-01

    Good skid resistance of a pavement surface is essential for road safety. Loss of skid resistance can lead to property damage and loss of lives. Ever increasing need of driver safety poses challenges to the highway authorities to evaluate pavement conditions even more precisely under different condit

  20. Analysis and design optimization of flexible pavement

    Energy Technology Data Exchange (ETDEWEB)

    Mamlouk, M.S.; Zaniewski, J.P.; He, W.

    2000-04-01

    A project-level optimization approach was developed to minimize total pavement cost within an analysis period. Using this approach, the designer is able to select the optimum initial pavement thickness, overlay thickness, and overlay timing. The model in this approach is capable of predicting both pavement performance and condition in terms of roughness, fatigue cracking, and rutting. The developed model combines the American Association of State Highway and Transportation Officials (AASHTO) design procedure and the mechanistic multilayer elastic solution. The Optimization for Pavement Analysis (OPA) computer program was developed using the prescribed approach. The OPA program incorporates the AASHTO equations, the multilayer elastic system ELSYM5 model, and the nonlinear dynamic programming optimization technique. The program is PC-based and can run in either a Windows 3.1 or a Windows 95 environment. Using the OPA program, a typical pavement section was analyzed under different traffic volumes and material properties. The optimum design strategy that produces the minimum total pavement cost in each case was determined. The initial construction cost, overlay cost, highway user cost, and total pavement cost were also calculated. The methodology developed during this research should lead to more cost-effective pavements for agencies adopting the recommended analysis methods.

  1. Pavement Crack Detection Using Spectral Clustering Method

    Directory of Open Access Journals (Sweden)

    Jin Huazhong

    2015-01-01

    Full Text Available Pavement crack detection plays an important role in pavement maintaining and management, nowadays, which could be performed through remote image analysis. Thus, edges of pavement crack should be extracted in advance; in general, traditional edge detection methods don’t consider phase information and the spatial relationship between the adjacent image areas to extract the edges. To overcome the deficiency of the traditional approaches, this paper proposes a pavement crack detection algorithm based on spectral clustering method. Firstly, a measure of similarity between pairs of pixels is taken into account through orientation energy. Then, spatial relationship is needed to find regions where similarity between pixels in a given region is high and similarity between pixels in different regions is low. After that, crack edge detection is completed with spectral clustering method. The presented method has been run on some real life images of pavement crack, experimental results display that the crack detection method of this paper could obtain ideal result.

  2. Comparison of laboratory test performance between asphalt-rubber hot mix and dense graded asphalt concrete

    OpenAIRE

    Sousa, Jorge B.; Pais, Jorge C.; Stubstad, Richard N.

    2000-01-01

    "Reflective cracking in pavements : research in practice" contains the Proceedings of the 4th International RILEM Conference on Reflective Cracking in Pavements (Proceedings PRO11). Asphalt-Rubber Hot-Mix (ARHM) has shown a higher resistance to flexural and reflective fatigue cracking, and also to permanent deformation, than conventional Dense Graded Asphalt Concrete (DGAC). Experience has demonstrated that with ARHM, a significant reduction in overlay thickness is possible, especially in...

  3. Improving Rutting Resistance of Pavement Structures Using Geosynthetics: An Overview

    Directory of Open Access Journals (Sweden)

    Sina Mirzapour Mounes

    2014-01-01

    Full Text Available A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting.

  4. Improving rutting resistance of pavement structures using geosynthetics: an overview.

    Science.gov (United States)

    Mirzapour Mounes, Sina; Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting).

  5. Improving rutting resistance of pavement structures using geosynthetics: an overview.

    Science.gov (United States)

    Mirzapour Mounes, Sina; Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting). PMID:24526919

  6. 浅析公路路基路面压实施工%Analysis of the Road Compaction Construction of Subgrade and Pavement

    Institute of Scientific and Technical Information of China (English)

    吕国锋

    2013-01-01

      本文着重对公路工程路基的路面压实施工进行了阐述,并详细介绍了影响路基路面压实施工的因素。同时,还提出了一些具体的路面压实施工技术措施,以实现公路工程路基路面压实施工技术的不断提升。%In this article, the author focuses on the compaction construction of highway subgrade pavement, and describes fa-ctors that af ect the subgrade and pavement compaction constr-uction in detail, and also put forward some concrete pavement compaction construction technical measures to achieve the co-ntinues improve the construction technology of subgrade and pavement compaction of highway engineering.

  7. Flexural fatigue characteristics of steel fiber reinforced recycled aggregate concrete (SFRRAC)

    OpenAIRE

    Heeralal M.; Kumar Rathish P.; Rao Y.V.

    2009-01-01

    This research work is aimed at investigating the flexural fatigue behavior of Steel Fiber Reinforced Recycled Aggregate Concrete (SFRRAC). This study gains importance in view of the wide potential for demolished concrete to serve as a source of quality aggregate feed stock in a variety of structural and non-structural applications. This is a continuation of a series of investigations being conducted aimed at optimizing the utilization of recycled aggregate concrete in rigid pavements. A total...

  8. Strength Development and Water Permeability of Engineered Biomass Aggregate Pervious Concrete

    OpenAIRE

    Shahidan S.; Koh H. B.; Sharif Alansi A. M.; Loon L. Y.

    2016-01-01

    Pervious concrete has a high rate of permeability, low strength and high porosity. It is commonly used in the area of storm water management. However, its use has been limited to pavements with low volume traffic. Pervious concrete is different from normal concrete as the mixture contains no fine aggregates. The aggregate is usually of a single size bonded by a cement paste. This study focuses mainly on the effect of Engineered Biomass Aggregate (EBA) on the compressive strength and permeabil...

  9. Structural Precast Concrete Handbook

    DEFF Research Database (Denmark)

    Kjærbye, Per Oluf H

    Structural concept for precast concrete systems. Design og precast reinforced concrete components. Design of precast concrete connections. Illustrations on design of precast concrete buildings. Precast concrete assembly....

  10. Effects of cross-anisotropy and stress-dependency of pavement layers on pavement responses under dynamic truck loading

    Directory of Open Access Journals (Sweden)

    Rafiqul A. Tarefder

    2016-06-01

    Full Text Available Previous studies by the authors have determined pavement responses under dynamic loading considering cross-anisotropy in one layer only, either the cross-anisotropic viscoelastic asphalt concrete (AC layer or the cross-anisotropic stress-dependent base layer, but not both. This study evaluates pavement stress–strain responses considering cross-anisotropy in all layers, i.e. AC, base and subbase, using finite element modeling (FEM technique. An instrumented pavement section on Interstate I-40 near Albuquerque, New Mexico was used in ABAQUS framework as model geometry. Field asphalt cores were collected and tested in the laboratory to determine the cross-anisotropy (n-values defined by horizontal to vertical modulus ratio, and other viscoelastic parameters as inputs of the model incorporated through user defined material interface (UMAT functionality in ABAQUS. Field base and subbase materials were also collected and tested in the laboratory to determine stress-dependent nonlinear elastic model parameters, as inputs of the model, again incorporated through UMAT. The model validation task was carried out using field-measured deflections and strain values under falling weight deflectometer (FWD loads at the instrumented section. The validated model was then subjected to an actual truck loading for studying cross-anisotropic effects. It was observed that horizontal tensile strain at the bottom of the AC layer and vertical strains in all layers decreased with an increase in n-value of the asphalt layer, from n < 1 (anisotropy to n=1 (isotropy. This indicates that the increase in horizontal modulus caused the decrease in layer strains. It was also observed that if the base and subbase layers were considered stress-dependent instead of linear elastic unbound layers, the horizontal tensile strain at the bottom of the asphalt layer increased and vertical strains on top of the base and subbase also increased.

  11. Effects of cross-anisotropy and stress-dependency of pavement layers on pavement responses under dynamic truck loading

    Institute of Scientific and Technical Information of China (English)

    Rafiqul A. Tarefder; Mesbah U. Ahmed; Asifur Rahman

    2016-01-01

    Previous studies by the authors have determined pavement responses under dynamic loading consid-ering cross-anisotropy in one layer only, either the cross-anisotropic viscoelastic asphalt concrete (AC) layer or the cross-anisotropic stress-dependent base layer, but not both. This study evaluates pavement stressestrain responses considering cross-anisotropy in all layers, i.e. AC, base and subbase, using finite element modeling (FEM) technique. An instrumented pavement section on Interstate I-40 near Albu-querque, New Mexico was used in ABAQUS framework as model geometry. Field asphalt cores were collected and tested in the laboratory to determine the cross-anisotropy (n-values) defined by horizontal to vertical modulus ratio, and other viscoelastic parameters as inputs of the model incorporated through user defined material interface (UMAT) functionality in ABAQUS. Field base and subbase materials were also collected and tested in the laboratory to determine stress-dependent nonlinear elastic model pa-rameters, as inputs of the model, again incorporated through UMAT. The model validation task was carried out using field-measured deflections and strain values under falling weight deflectometer (FWD) loads at the instrumented section. The validated model was then subjected to an actual truck loading for studying cross-anisotropic effects. It was observed that horizontal tensile strain at the bottom of the AC layer and vertical strains in all layers decreased with an increase in n-value of the asphalt layer, from n<1 (anisotropy) to n ¼ 1 (isotropy). This indicates that the increase in horizontal modulus caused the decrease in layer strains. It was also observed that if the base and subbase layers were considered stress-dependent instead of linear elastic unbound layers, the horizontal tensile strain at the bottom of the asphalt layer increased and vertical strains on top of the base and subbase also increased.

  12. Aircraf landing gear design in respect of pavement design

    OpenAIRE

    Fabre, C.; ALBIN, A; Balay, Jean Maurice

    2009-01-01

    This paper considers the close relationship between aircraft landing gear (LG) and pavement design in respect of airfield pavement compatibility. In pavement design and analysis, we usually deal with pavement structures, materials and design thickness procedure but rarely aircraft LG design This paper emphasizes key drivers, which must be considered for new aircraft LG design to achieve aircraft pavement compatibility. Several parameters such as number & size of wheels, type of gear, brakes, ...

  13. Simultaneous Measurement and Analysis of Noise Levels in Flexible and Rigid Pavements

    Directory of Open Access Journals (Sweden)

    Hakan Yıldırım

    2014-06-01

    Full Text Available Although concrete roads have been used worldwide for years, the same improvement could not exist in Turkey and therefore, bituminous (hot mix asphalt roads were preferred instead.In this paper, the vastly built HMA (Hot Mix Asphalt roads and rarely preferred concrete roads were compared based on their level of noise. For this purpose, the concrete road at the length of 2 kilometers between Afyonkarahisar and Emirdag; also the transition point to the HMA road (which continues after the concrete road was observed.Both concrete and HMA road ends of this transition point was equipped with a noise measurement device and a camera was installed separately for providing minimum level of noise interference. Consequently, change in the noise levels depending on the building material of roads was recorded simultaneously. These factors was analysed and various models related to the sort of coating was provided. At this stage, the distance between set up points was kept as short as possible in order to prevent different results in the density of traffic and also in the flow rate.Result of various measurements and analysis provided the noise levels of concrete roads being 4 dB(A less than HMA roads in the comparison based on the same level of vehicle composition and traffic flow. Encouraging the construction of concrete roads in our country is emphasized accordingly.

  14. Response of pavement to freeze-thaw cycles: Lebanon, New Hampshire, regional airport

    Science.gov (United States)

    Allen, Wendy L.; Quinn, William F.; Keller, Donald; Eaton, Robert A.

    1989-01-01

    In 1978 reconstruction was begun on the runway of the Lebanon Regional Airport, Lebanon, New Hampshire. The runway had experienced severe differential frost heaving and cracking during the previous three winters, which had resulted in closure of the facility during periods of extreme roughness. Temperature sensors were placed within the newly constructed pavement sections, and during the winters of 1979, 1980, and 1982 temperature data were recorded, and level surveys and repeated plate bearing tests were performed in order to provide data for the investigation. The three pavement sections were constructed to investigate the effect of section thickness on the level of frost protection provided. The sections consisted of 4 in. of asphalt concrete, 6 in. of crushed gravel and 22,30 dn 38 in. of well-graded sand subbase material. The 48-in section provided the highest level of frost protection to the subgrade. However, all three pavement sections maintained resilient stiffness values during the spring thaw period on the order of two to three times that of the pavement before reconstruction. Also, frost heave in all sections was reduced to levels that would not cause difficulty for aircraft using the facility.

  15. Automatic processing and modeling of GPR data for pavement thickness and properties

    Science.gov (United States)

    Olhoeft, Gary R.; Smith, Stanley S., III

    2000-04-01

    A GSSI SIR-8 with 1 GHz air-launched horn antennas has been modified to acquire data from a moving vehicle. Algorithms have been developed to acquire the data, and to automatically calibrate, position, process, and full waveform model it without operator intervention. Vehicle suspension system bounce is automatically compensated (for varying antenna height). Multiple scans are modeled by full waveform inversion that is remarkably robust and relatively insensitive to noise. Statistical parameters and histograms are generated for the thickness and dielectric permittivity of concrete or asphalt pavements. The statistical uncertainty with which the thickness is determined is given with each thickness measurement, along with the dielectric permittivity of the pavement material and of the subgrade material at each location. Permittivities are then converted into equivalent density and water content. Typical statistical uncertainties in thickness are better than 0.4 cm in 20 cm thick pavement. On a Pentium laptop computer, the data may be processed and modeled to have cross-sectional images and computed pavement thickness displayed in real time at highway speeds.

  16. Amenability of Muzret bituminous coal to oil agglomeration

    Energy Technology Data Exchange (ETDEWEB)

    Sahinoglu, E.; Uslu, T. [Karadeniz Technical University, Department of Mining Engineering, 61080 Trabzon (Turkey)

    2008-12-15

    Laboratory scale agglomeration tests were undertaken to investigate the amenability of Muzret (Yusufeli-Artvin) bituminous coal to oil agglomeration. Kerosene was extensively used as oil in the tests. In addition, fuel oil, diesel oil, and hazelnut oil were also used in order to determine the effect of oil type. The effects of the parameters including coal content, kerosene content, agglomeration time, coal particle size, pH, oil type, and agitation rate, on the combustible matter recovery, ash reduction and pyritic sulphur reduction, were investigated. It was found that Muzret bituminous coal could be readily cleaned by oil agglomeration with substantial reductions in ash and pyritic sulphur content. Maximum combustible matter recovery, ash reduction and pyritic sulphur reduction were achieved to be 85.54%, 59.98%, and 85.17%, respectively. (author)

  17. Performance of PAHs emission from bituminous coal combustion

    Institute of Scientific and Technical Information of China (English)

    严建华; 尤孝方; 李晓东; 倪明江; 尹雪峰; 岑可法

    2004-01-01

    Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion.

  18. Assessment of an action against environmental noise: Acoustic durability of a pavement surface with crumb rubber.

    Science.gov (United States)

    Vázquez, V F; Luong, J; Bueno, M; Terán, F; Paje, S E

    2016-01-15

    Environmental noise is a worldwide problem that has an adverse effect in the quality of life of urban population. Some work has shown that there is a correlation between environmental noise and health issues as sleep disturbance or annoyance. This study presents the time evolution of a test track fabricated with an asphalt mixture with 20% of crumb rubber by weight of bitumen, added by the wet process. A complete surface characterization has been performed by determining tire/pavement sound levels, road texture profiles, in-situ dynamic stiffness and sound absorption of compacted and extracted sample cores. Two measurement campaigns were performed: just after mixture laying and after 3 years in service. This study confirms that the use of crumb rubber as a modifier of bituminous binders (CRMB) can improve the pavement characteristics: gap-graded mixtures with crumb rubber can be used in the action plans as urban rehabilitation measure to fight noise pollution. However, this noise reduction seems to decrease with age at a rate of approximately 0.15 dB(A) per year. PMID:26519582

  19. Identification of aggregates for Tennessee bituminous surface courses

    Science.gov (United States)

    Sauter, Heather Jean

    Tennessee road construction is a major venue for federal and state spending. Tax dollars each year go to the maintenance and construction of roads. One aspect of highway construction that affects the public is the safety of its state roads. There are many factors that affect the safety of a given road. One factor that was focused on in this research was the polish resistance capabilities of aggregates. Several pre-evaluation methods have been used in the laboratory to predict what will happen in a field situation. A new pre-evaluation method was invented that utilized AASHTO T 304 procedure upscaled to accommodate surface bituminous aggregates. This new method, called the Tennessee Terminal Textural Condition Method (T3CM), was approved by Tennessee Department of Transportation to be used as a pre-evaluation method on bituminous surface courses. It was proven to be operator insensitive, repeatable, and an accurate indication of particle shape and texture. Further research was needed to correlate pre-evaluation methods to the current field method, ASTM E 274-85 Locked Wheel Skid Trailer. In this research, twenty-five in-place bituminous projects and eight source evaluations were investigated. The information gathered would further validate the T3CM and find the pre-evaluation method that best predicted the field method. In addition, new sources of aggregates for bituminous surface courses were revealed. The results of this research have shown T3CM to be highly repeatable with an overall coefficient of variation of 0.26% for an eight sample repeatability test. It was the best correlated pre-evaluation method with the locked wheel skid trailer method giving an R2 value of 0.3946 and a Pearson coefficient of 0.710. Being able to predict field performance of aggregates prior to construction is a powerful tool capable of saving time, money, labor, and possibly lives.

  20. Water quality and quantity assessment of pervious pavements performance in experimental car park areas.

    Science.gov (United States)

    Sañudo-Fontaneda, Luis A; Charlesworth, Susanne M; Castro-Fresno, Daniel; Andres-Valeri, Valerio C A; Rodriguez-Hernandez, Jorge

    2014-01-01

    Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates and basic oxygen furnace slag). This study therefore encompasses the majority of the materials used as permeable surfaces and sub-base layers all over the world. Effluent from the test bays was monitored for dissolved oxygen, pH, electric conductivity, total suspended solids, turbidity and total petroleum hydrocarbons in order to analyze the behaviour shown by each combination of surface and sub-base materials. In addition, permeability tests were undertaken in all car parks using the 'Laboratorio Caminos Santander' permeameter and the Cantabrian Portable Infiltrometer. All results are presented together with the influence of surface and sub-base materials on water quality indicators using bivariate correlation statistical analysis at a confidence level of 95%. The polymer-modified porous concrete surface course in combination with limestone aggregate sub-base presented the best performance.

  1. Water quality and quantity assessment of pervious pavements performance in experimental car park areas.

    Science.gov (United States)

    Sañudo-Fontaneda, Luis A; Charlesworth, Susanne M; Castro-Fresno, Daniel; Andres-Valeri, Valerio C A; Rodriguez-Hernandez, Jorge

    2014-01-01

    Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates and basic oxygen furnace slag). This study therefore encompasses the majority of the materials used as permeable surfaces and sub-base layers all over the world. Effluent from the test bays was monitored for dissolved oxygen, pH, electric conductivity, total suspended solids, turbidity and total petroleum hydrocarbons in order to analyze the behaviour shown by each combination of surface and sub-base materials. In addition, permeability tests were undertaken in all car parks using the 'Laboratorio Caminos Santander' permeameter and the Cantabrian Portable Infiltrometer. All results are presented together with the influence of surface and sub-base materials on water quality indicators using bivariate correlation statistical analysis at a confidence level of 95%. The polymer-modified porous concrete surface course in combination with limestone aggregate sub-base presented the best performance. PMID:24718346

  2. Development of Mechanistic-Empirical Pavement Design for Tropical Climate Using Cement-Treated Base Layer

    Directory of Open Access Journals (Sweden)

    O. S. Aderinola

    2016-08-01

    Full Text Available A mechanistic-empirical pavement design method is developed characterising cement-treated base layers for pavement design in Nigeria or other similar tropical and subtropical countries. Asphalt Concrete surface, Subbase and Aggregate base were characterised based on back calculation data from Claros et al (1986 while cement-treated base layer was based on modulus tests that had been conducted by past researchers. Failure criteria for the Asphalt Concrete fatigue failure and the subgrade rutting failure were based on those by Claros and Ijeh (1987 for Nigerian pavements. Cracking criterion used for the cement-treated layer was that developed by Otee et al. (1982. The comparison between the Soil-Cement and Aggregate base showed that at a low Equivalent Single Axle Load (ESAL (0.5 million repetitions was considered, the use of Aggregate base was better than Soil-Cement base. That for Aggregate base and Cement-Treated Gravel Base showed that the Cement-Treated Gravel Base was better than the Aggregate base at high ESAL (2.5 million repetitions was considered

  3. Assessment of highway pavements using GPR

    Science.gov (United States)

    Plati, Christina; Loizos, Andreas

    2015-04-01

    Highway infrastructure is a prerequisite for a functioning economy and social life. Highways, often prone to congestion and disruption, are one of the aspects of a modern transport network that require maximum efficiency if an integrated transport network, and sustainable mobility, is to be achieved. Assessing the condition of highway structures, to plan subsequent maintenance, is essential to allow the long-term functioning of a road network. Optimizing the methods used for such assessment will lead to better information being obtained about the road and underlying ground conditions. The condition of highway structures will be affected by a number of factors, including the properties of the highway pavement, the supporting sub-base and the subgrade (natural ground), and the ability to obtain good information about the entire road structure, from pavement to subgrade, allows appropriate maintenance programs to be planned. The maintenance of highway pavements causes considerable cost and in many cases obstruction to traffic flow. In this situation, methods that provide information on the present condition of pavement structure non-destructively and economically are of great interest. It has been shown that Ground-Penetrating-Radar (GPR), which is a Non Destructive Technique (NDT), can deliver information that is useful for the planning of pavement maintenance activities. More specifically GPR is used by pavement engineers in order to determine physical properties and characteristics of the pavement structure, information that is valuable for the assessment of pavement condition. This work gives an overview on the practical application of GPR using examples from highway asphalt pavements monitoring. The presented individual applications of GPR pavement diagnostics concern structure homogeneity, thickness of pavement layers, dielectric properties of asphalt materials etc. It is worthwhile mentioning that a number of applications are standard procedures, either

  4. The concrete construction optimization strategy%混凝土施工优化策略

    Institute of Scientific and Technical Information of China (English)

    郝志强

    2015-01-01

    Combining with the working experience of construction site,this paper summarized the optimization method of concrete pavement con-struction site,and from the factors of destruction of concrete pavement elaborated the material selection,mix proportion design,flatness control, maintenance and matters needing attention in concrete pavement construction,to ensure the construction quality of concrete pavement,so as to improve the service life of pavement.%结合施工现场的工作经验,总结了混凝土路面现场施工的优化方法,并从破坏混凝土路面的因素出发,对混凝土路面施工中材料选择、配合比设计、平整度控制、养护等注意事项进行了阐述,以保证混凝土路面的施工质量,从而提升路面的使用年限。

  5. Nonlinear Responses of a Two Dimensional Vehicle-pavement System

    Directory of Open Access Journals (Sweden)

    Shaohua Li

    2013-09-01

    Full Text Available The vehicle and pavement are usually investigated separately in vehicle dynamics and pavement dynamics. In this work, a new research scheme is proposed to link the vehicle and pavement model by tire loads and compute the nonlinear dynamic responses by analytical methods. A two-DOF nonlinear vehicle and a Bernoulli-Euler beam on a nonlinear elastic foundation with two simply supported ends compose the nonlinear vehicle-pavement system. The nonlinear tire loads are analytically gained using the averaging method. Then the nonlinear vibration equation of the pavement is obtained using Galerkin method and solved using the multiple scales method. The theoretical solutions are verified by numerical results and the effects of system parameters on pavement vibration are also studied. It is found that the pavement responses excited by tire loads attenuate quickly and small pavement mass, large foundation damping or foundation stiffness may decrease the pavement vibration.

  6. The optimization of concrete mixtures for use in highway applications

    Science.gov (United States)

    Moini, Mohamadreza

    Portland cement concrete is most used commodity in the world after water. Major part of civil and transportation infrastructure including bridges, roadway pavements, dams, and buildings is made of concrete. In addition to this, concrete durability is often of major concerns. In 2013 American Society of Civil Engineers (ASCE) estimated that an annual investment of 170 billion on roads and 20.5 billion for bridges is needed on an annual basis to substantially improve the condition of infrastructure. Same article reports that one-third of America's major roads are in poor or mediocre condition [1]. However, portland cement production is recognized with approximately one cubic meter of carbon dioxide emission. Indeed, the proper and systematic design of concrete mixtures for highway applications is essential as concrete pavements represent up to 60% of interstate highway systems with heavier traffic loads. Combined principles of material science and engineering can provide adequate methods and tools to facilitate the concrete design and improve the existing specifications. In the same manner, the durability must be addressed in the design and enhancement of long-term performance. Concrete used for highway pavement applications has low cement content and can be placed at low slump. However, further reduction of cement content (e.g., versus current specifications of Wisconsin Department of Transportation to 315-338 kg/m 3 (530-570 lb/yd3) for mainstream concrete pavements and 335 kg/m3 (565 lb/yd3) for bridge substructure and superstructures) requires delicate design of the mixture to maintain the expected workability, overall performance, and long-term durability in the field. The design includes, but not limited to optimization of aggregates, supplementary cementitious materials (SCMs), chemical and air-entraining admixtures. This research investigated various theoretical and experimental methods of aggregate optimization applicable for the reduction of cement content

  7. Children, urban care, and everyday pavements

    OpenAIRE

    Kim Kullman

    2014-01-01

    This paper takes a mundane piece of urban infrastructure, the pavement, as a starting point, approaching it through the experiences of 7–12-year-old children who journey between home and school in Helsinki, Finland. In doing so, the paper argues that the children and their travel companions are employing pavements to cultivate the caring potential of their city, whether this entails patting dogs, picking up empty bottles, or checking the safety of zebra crossings. Inspired by recent work on t...

  8. Research on Fatigue Properties of Asphalt Pavement on Mix Base%混合式基层沥青路面的疲劳特性分析研究

    Institute of Scientific and Technical Information of China (English)

    彭宏图

    2013-01-01

    According to the 06 standard design methods,AASHTO experiment methods and actual interlayer bonding state,the fatigue properties of three different bituminous pavements of composite base are analyzed in this paper.The results reveal that with the same thickness,the mixed asphalt pavement has a better fatigue life than the semi-rigid base AC pavement.For the purpose of analyzing the sensitivity of the fatigue property,the thickness of the pavement and modulus of graded gravel are also taken into account in three different asphalt pavements of composite.%采用了06版规范方法、考虑实际层间粘接状态的规范方法以及AASH00经验方法对3种类型的混合式基层沥青路面的疲劳特性进行了分析研究,得出了相同厚度的混合式基层沥青路面比半刚性基层沥青路面具有更长的疲劳寿命的结论.并对不同结构层厚度、级配碎石模量对3种类型的混合式基层沥青路面的疲劳特性的敏感性进行了分析.

  9. Glazed Concrete

    DEFF Research Database (Denmark)

    Bache, Anja Margrethe

    2010-01-01

    Why glazed concrete? Concrete hardens and finds its strength at room temperature whereas clay products must first be fired before they achieve this strength. They are stronger and three times as durable as clay products, which is a weighty reason for choosing concrete.5 Another reason, which....... If this succeeds, it will be possible to manufacture thin, large-scale glazed concrete panels comparable in size to concrete sandwich construction and larger which, with or without back-casting, can work as load-bearing construction elements....

  10. Environmental interactions of Sulphlex pavement.

    Science.gov (United States)

    Ferenbaugh, R W; Gladney, E S; Soholt, L F; Lyall, K A; Kimber Wallwork-Barber, M; Herman, L E

    1992-01-01

    Sulphlex, a mixture of elemental sulfur and plasticizers, has been considered for use as an asphalt substitute in road construction. Because this material contains substantial quantities of elemental sulfur, it is a potential substrate for growth of sulfur-oxidising bacteria. Experiments, performed to determine the susceptibility of Sulphlex in Sulphlex-containing media to degradation by Thiobacillus thiooxidans, resulted in breakdown of the Sulphlex material and concomitant production of acid. In concurrent studies, plants were grown in Sulphlex-amended soils. These plants exhibited higher sulfur content and reduced productivity as compared with plants grown in unamended soils, indicating that Sulphlex was being broken down in the soil and that the breakdown products were apparently having a detrimental effect on plant productivity. These experiments indicate that naturally occurring sulfur-oxidising bacteria have the potential to break down Sulphlex paving material, resulting in adverse effects on both the structural integrity of the pavement and the local environment. PMID:15091995

  11. Pavement Performance Index for Indian rural roads

    Directory of Open Access Journals (Sweden)

    Abhay Tawalare

    2016-09-01

    Full Text Available The performance of a road is evaluated from time to time so as to improve its quality and helps in planning maintenance of roads. For this purpose various pavement deteriorating models as a decision tool are available. But they are not easy to use for field engineers due to either huge past data requirement or complicated calculations. Therefore, this paper presents a Pavement Performance Index for rural roads by using simple methodology. The distress parameters of rural roads were identified through literature review. Similarly rating criteria for each distress parameters were identified through literature. For final selection of distress parameters in context of Indian rural road, opinions of five highly experienced industrial experts were taken. After that the weightage for severity of each parameter causing distress of pavement is calculated by using data of questionnaire survey in which 117 professionals working in Pradhan Mantri Gram Sadak Yojana across the country were participated. The paper suggests a formula to decide Pavement Performance Index that depends on rating criterion and severity weightage of distress parameters of pavement performance. The study concluded that suggested Pavement Performance Index makes calculations easy for field engineers and will be useful to decide priority list of rural roads for repair and maintenance schedule.

  12. A STUDY OF BITUMINOUS SHUNGITE BINDER ON THE SCANNING MICROSCOPE

    OpenAIRE

    K. A. Andrianov; D V Ivanov; V. P. Yartsev

    2012-01-01

    Statement of the problem. It is possible to improve working conditions of road pavement and to use it more efficiently by regulating water-thermal conditions of the subgrade thereby reducing humidity in the design period and mitigating its seasonal changes.Results and conclusions. It is suggested to use extruded foam polystyrene as a heating layer. The thermal fluctuation approach was applied to failure and deformation processes. Physical constants for the analytical description of these proc...

  13. Sulfur concrete haul roads at Suncor oil sands mines

    Energy Technology Data Exchange (ETDEWEB)

    Abraha, D.; Sego, D.; Donahue, R.; Biggar, K. [Alberta Univ., Edmonton, AB (Canada). Geotechnical Center

    2004-07-01

    Well constructed haul roads are necessary to ensure the efficient use of ultra large haul trucks used at oil sand mining operations in northern Alberta. Haul roads at Suncor are presently constructed with crushed limestone, gravel, lean oil sand and till, but they deteriorate severely during the summer due to material softening. Suncor conducted a study to determine the feasibility of building mine haul roads at their oil sand mines using concrete prepared from by-products and mine wastes such as sulfur, fly ash, coke and tailings sand. The physical and mechanical properties of different mixes of sulfur concrete were characterized in laboratory studies that involved compression measuring and split tensile and freeze thaw durability tests. The geochemical interaction of sulfur concrete with the near surface environment was also studied with reference to the operational life of the haul road and interaction of sulfur concrete with ground water. A haul road test section was designed based on the resilient modulus design method. A finite element analysis was used to calculate the stress and strain distributions in the road caused by truck tires. The pavement thickness was determined based on the truck loads, the resilient modulus and the strength of the sulfur concrete and subgrade material. It was concluded that sulfur concrete produced from mine wastes is much stronger and stiffer than the existing haul road material. Therefore, better haul roads can be constructed with reduced pavement thicknesses using tailing sand sulfur concrete. 8 refs., 4 tabs., 14 figs.

  14. Concrete Hinges

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

    2014-01-01

    In the first part of the 20th century concrete hinges developed by Freyssinet and Mesnager were widely tested and implemented in concrete structures. The concrete hinges were used a great deal in closed-spandrel arch bridges. Since such a bridge type has not been competitive for the past 40 years......, the research in concrete hinges has not evolved significantly in that period. But introducing a new state-of-the-art concrete arch bridge solution (Pearl-Chain arches invented at the Technical University of Denmark) creates a necessity of a concrete hinge research based on modern standards. Back when research...... in concrete hinges was more common different designs were proposed for the geometry and reinforcement. Previous research focused on fatigue, multi-axial stresses around the hinge throat, and the relation between rotation- and moment. But many different test-setups were proposed by different researchers...

  15. FLEXIBLE PAVEMENT REHABILITATION DESIGN BASED ON PAVEMENT SERVICE LIFE TIME SPAN LEFT

    OpenAIRE

    Gamelyak, I.; Shevchuk, V.

    2005-01-01

    The design of flexible pavement rehabilitation is analysed in terms of durability-cost. A notion of the remaining service life span is described. the model of rehabilitation strategy selection is presented for both design project and operation stages. the results can be used in the pavement management system.

  16. Waste to Wealth; The Utilization of Scrap Tyre as Aggregate in Bituminous Mixes for Road Construction

    Directory of Open Access Journals (Sweden)

    Oba, A. L.,

    2015-11-01

    Full Text Available The problem associated with solid waste management is on the increase both in the industries, urban cities and in the rural areas. In the United States of America, Asia and Europe, there are over hundreds of waste to wealth combustion plants from where solid wastes are incinerated. In Nigeria, amidst the increasing importation of vehicle tyre such plants are scarcely in existence to enhance generation of revenue from waste through the extraction of raw material for the production of light weight aggregates, printing ink, paints, shoe polish, dry cell and battery heads. This research paper seeks to utilize vehicle scrap tyre (VST as aggregates in asphaltic mixture by adopting the dry process to evaluate the effect of rubber-bitumen interaction on asphaltic concrete properties; laboratory investigation using 4.75mm, 2.36mm and 0.600mm chunk tyre particle size modified asphalt mixture containing 2%, 4%, 6%, 8% and 10% scrap tyre and 0% tyre content as control mixture. The mixtures were subjected to Marshall Tests where the stability, flow, percentage air void, unit weight, void mineral aggregate, height of specimen and specific gravity were determined. The results obtained shows that as tyre percentage increase the stability, unit weight and specific gravity value decreases. On the other hand, as the tyre content increases, the flow and height of specimen increases while as the tyre content increases the percentage air void and VMA increased for 4.75mm Tyre Particle Size (TPS and 2.36mm TPS while for 0.600mm TPS, reverse is the case. In summary and in comparism with standard specification for road construction material, the Marshall tests conducted on the tyre modified specimens remained intact and by interpretation; material possessing such property indicates good impact resistance when use as surface course in flexible pavement. Conclusively, the use of 10% 4.75mm, 4% 2.36mm or 4% 0.600mm TPS by weight of aggregate in asphaltic concrete is

  17. Simulation of cooling effect of newly-innovated urban pavements on water and heat budgets

    Science.gov (United States)

    Nakayam, T.; Fujita, T.

    2007-12-01

    People often suffer from the intense summer heat in Japan. This trend is increasing in urban areas because of the heat island effect and global warming. The present research evaluated the effect of pavements made of traditional and new materials on water and heat budgets. We coupled the NIES Integrated Catchment-based Eco- hydrology (NICE) model (Nakayama, 2007; Nakayama and Watanabe, 2004, 2006, 2007; Nakayama et al., 2006, 2007) to an urban canopy model in order to simulate the water and heat budgets in various types of natural and artificial pavements (covered by lawn, concrete, steel plate, synthetic rubber sheet, infiltration and water-holding blocks), and to evaluate the role of a new surface material in promoting evaporation and cooling to counter the heat island phenomenon (NICE-URBAN), by comparing with the simplified empirical model. Furthermore, using the heat conductivities of natural soil, we arranged these values for artificial pavement in the model equations by including the effect of the amount of water on the heat characteristics in the material. The simulated belowground water agreed with the observed value because this model includes the processes of both interception store and soil moisture store. The NICE-URBAN simulated more correctly the cooling of water-holding pavement during the intense heat of summer in an urban area than the empirical model. Because the model estimates that the air temperature at the water-holding pavement is 2 (deg.) lower than that at the lawn and 5 (deg.) lower than that at the building rooftop, it is very powerful to use this material for positive cooling effect in combination with the lawn for passive cooling effect. The simulation of NICE-URBAN showed that the decrease of surface temperature in water-holding pavement is closely related to the promotion of evaporation from the surface, the water volume of the pavement and the surface reflectance. References; 1)Nakayama,T.,Watanabe,M.,WRR,40,doi:10.1029/2004WR003174

  18. Improving a pavement-watering method on the basis of pavement surface temperature measurements

    CERN Document Server

    Hendel, Martin; Diab, Youssef; Royon, Laurent

    2014-01-01

    Pavement-watering has been studied since the 1990's and is currently considered a promising tool for urban heat island reduction and climate change adaptation. However, possible future water resource availability problems require that water consumption be optimized. Although pavement heat flux can be studied to improve pavement-watering methods (frequency and water consumption), these measurements are costly and require invasive construction work to install appropriate sensors in a dense urban environment. Therefore, we analyzed measurements of pavement surface temperatures in search of alternative information relevant to this goal. It was found that high frequency surface temperature measurements (more than every 5 minutes) made by an infrared camera can provide enough information to optimize the watering frequency. Furthermore, if the water retaining capacity of the studied pavement is known, optimization of total water consumption is possible on the sole basis of surface temperature measurements.

  19. Sorption of aqueous phosphorus onto bituminous and lignitous coal ashes

    Energy Technology Data Exchange (ETDEWEB)

    Yan Jinying; Kirk, Donald W. [Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5 (Canada); Jia, Charles Q. [Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5 (Canada)], E-mail: cqjia@chem-eng.toronto.edu; Liu Xinan [College of Chemical Engineering, Chongqing University, Chongqing (China)

    2007-09-05

    Aiming at the development of a phosphorus removal technology for waste water, phosphate (PO{sub 4}{sup 3-}) retention behavior of bituminous and lignitous coal ashes was investigated using a batch reactor. Ash samples, including fresh and weathered fly and bottom ashes, were studied for their sorption isotherms and reversibility. Fly ashes had a much higher phosphate retention capacity (4000-30,000 mg P/kg) than bottom ashes (15-600 mg P/kg). Lignitous coal ashes were more capable of retaining phosphate than bituminous coal ashes. The retention process was largely irreversible, and the irreversibility increased with the increase in the retention capacity. Weathering enlarged the retention capacity of the bituminous bottom ash, but substantially lowered that of the fly ash, likely due to the difference in the weather-induced changes between the fly and bottom ashes. Sorption isotherms of fly ashes were found to be adequately represented by the Langmuir model while those of bottom ashes fitted better to the Freundlich model. Concentrations of Ca{sup 2+} and PO{sub 4}{sup 3-} in the aqueous phase were measured at the end of sorption and desorption experiments, and were compared with solubilities of three calcium phosphate minerals. The aqueous solutions were saturated or super-saturated with respect to tricalcium phosphate (Ca{sub 3}(PO{sub 4}){sub 2}) and hydroxyapatite (Ca{sub 5}(PO{sub 4}){sub 3}OH), and slightly under-saturated with respect to amorphous calcium phosphate. It is concluded that precipitation of calcium phosphate is the predominant mechanism for phosphate retention by coal ash under the conditions studied. There is a strong and positive correlation between alkalinity and phosphate sorption capacity. Consequently, acid neutralization capacity (ANC) can be used as an indicator of phosphate sorption capacity of coal ashes.

  20. SIMULATION OF TEMPERATURE AND TRANSPORT LOAD IMPACT ON FORMATION AND DEVELOPMENT OF CRACKS ON ASPHALT-CONCRETE ROAD SURFACES

    Directory of Open Access Journals (Sweden)

    I. Melnikova

    2012-01-01

    Full Text Available An analysis of statistical data has shown that about 60 % of all types of road surface destructions and damages in the Republic of Belarus are attributed to cracks (separate, frequent and cracks network. The process of cracks formation in the asphalt concrete pavement is rather complicated and it is affected by a number of factors. The most important and determining factors are character and value of traffic loads, temperature action, road pavement structure, properties of materials used for its layers. Some regularities of the cracks formation and development in the asphalt-concrete layers of the pavement have been established on the basis of the physical and mathematical modeling. Application of a finite  element  method for  calculations  has made it possible to determine  numerical values of compressive and tensile stresses arising due to temperature action and traffic load, deflection of road pavement constructive layers. The paper contains recommendations for a road pavement design and repair of asphalt-concrete pavements which have been made on the basis of the obtained data analysis.

  1. Knowledge Discovery and Pavement Performance: Intelligent Data Mining

    NARCIS (Netherlands)

    Miradi, M.

    2009-01-01

    The main goal of the study was to discover knowledge from data about asphalt road pavement problems to achieve a better understanding of the behavior of them and via this understanding improve pavement quality and enhance its lifespan. Four pavement problems were chosen to be investigated; raveling

  2. Performance of pavements designed with low-cost materials

    Science.gov (United States)

    Grau, R. W.; Yrjanson, W. A.; Packard, R. G.; Barksdale, R. D.; Potts, C. F.; Ruth, B. E.; Smith, L. L.; Huddleston, I. J.; Vinson, T. S.; Hicks, R. G.

    1980-04-01

    The following areas are discussed. Utilization of marginal aggregate materials for secondary road surface layers; econocrete pavements; current practices; construction and performance of sand-asphalt bases and performance of sand-asphalt and limerock pavements in Florida. Cement stabilization of degrading aggregates use of crushed stone screenings in highway construction (abridgement); and sulfur-asphalt pavement technology are also reviewed.

  3. Effect of age of permeable pavements on their infiltration function

    NARCIS (Netherlands)

    Boogaard, Floris; Lucke, Terry; Beecham, Simon

    2013-01-01

    This study describes field investigations designed to compare the infiltration capacities of 55 permeable pavement systems installed in the Netherlands and in Australia. The ages of the pavements varied from 1 to 12 years. Using infiltrometer testing, the performance of the pavements has been compar

  4. EFFECTS OF PAVEMENT SURFACE TEMPERATURE ON THE MODIFICATION OF URBAN THERMAL ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    SARAT, Adebayo-Aminu

    2012-01-01

    Full Text Available Urban centres continue to experience escalating average summer temperature over the last fifty years. Temperature in the urban core cites have been rising due to rapid growth of urbanization in the latter half of the twentieth century (Akbari et al., 1989. Outdoor experiments were conducted to investigate the effects of different movement of materials on the urban thermal environment. Meteorological conditions such as air temperature, pavement surface temperature, Relative humidity and wind velocity were recorded to determine temperature differences among Asphalt/concrete, interlocking bricks and grass surfaces.

  5. Assessment of french design method for flexible pavement by mean of the LCPC's ALT facility

    OpenAIRE

    Balay, Jean Maurice; Kerzreho, Jean Pierre

    2008-01-01

    One of the three rings of the LCPC's ALT facility has been equipped in 2002 with a 3 meters high waterproof concrete pit and a pumping station, making possible to completely control the water table level in the soil supporting the experimental pavement. The pit has been filled by clayey-silty sand, which the modulus varies from 110 to 85 MPa according to the water content. This soil has been chosen for its water-content susceptibility, but also for its permeability properties, making possible...

  6. Example of using small falling weight deflectomer (FWD) for Earth structures and low cost road pavement in Japan

    Science.gov (United States)

    Shibata, Hideaki; Tanaka, Yasutomo; Ono, Isamu; Okano, Tsuyoshi

    2007-01-01

    The FWD (Falling Weight Deflectometer) is an instrument which makes the weight fall freely on its loading plate to apply impact load and measures the displacement caused by the fall at the center of impact load and also at the points in radial direction from the center of impact load. A kind of instrument which is mounted on or drawn by a vehicle used for construction of concrete pavement or asphalt pavement of a runway is usually called FWD. The impact load of FWD is 49KN to 196kN and it can obtain the modulus of elasticity of each pavement layer by back analysis based on the theory of multi-layer elasticity using 6 to 8 of extemal displacement sensors. On the other hand, the small FWD is an FWD which is constructed small and easy and is applicable for hand carry. It makes the weight fall freely on the loading plate to apply impact load and measures the load and displacement caused by the fall. It was developed for mainly assessing the rigidity and bearing capacity of the subgrade easily and promptly. It can measure many points in short term and obtain coefficient of subgrade reaction and modulus of subgrade elasticity without using reaction facilities like as plate bearing test or CBR test. It has also been tried to apply the small FWD to low cost asphalt road pavement (later called as low cost road pavement). Application examples of small FWD test for earth structure and low cost load pavement in Japan are shown and the methods and test results are stated in this report.

  7. Pavement Sealcoat, PAHs, and the Environment

    Science.gov (United States)

    Van Metre, P. C.; Mahler, B. J.

    2011-12-01

    Recent research by the USGS has identified coal-tar-based pavement sealants as a major source of polycyclic aromatic hydrocarbons (PAHs) to the environment. Coal-tar-based sealcoat is commonly used to coat parking lots and driveways and is typically is 20-35 percent coal tar pitch, a known human carcinogen. Several PAHs are suspected mutagens, carcinogens, and (or) teratogens. In the central and eastern U.S. where the coal-tar-based sealants dominate use, sum-PAH concentration in dust particles from sealcoated pavement is about 1,000 times higher than in the western U.S. where the asphalt-based formulation is prevalent. Source apportionment modeling indicates that particles from sealcoated pavement are contributing the majority of the PAHs to recent lake sediment in 35 U.S. urban lakes and are the primary cause of upward trends in PAHs in many of these lakes. Mobile particles from parking lots with coal-tar-based sealcoat are tracked indoors, resulting in elevated PAH concentrations in house dust. In a recently completed study, volatilization fluxes of PAHs from sealcoated pavement were estimated to be about 60 times fluxes from unsealed pavement. Using a wide variety of methods, the author and colleagues have shown that coal-tar-based sealcoat is a major source of PAHs to the urban environment and might pose risks to aquatic life and human health.

  8. The Use Of Permeable Concrete For Ground Water Recharge

    Directory of Open Access Journals (Sweden)

    Akshay Tejankar

    2016-09-01

    Full Text Available In order to develop Smart Cities in India, we need to develop smart technologies and smart construction materials. Permeable concrete an innovative material is environment friendly and a smart material which can be used for construction of several structures. In India, the ground water table is decreasing at a faster rate due to reduction in ground water recharge. These days, the vegetation cover is replaced by infrastructure hence the water gets very less opportunity to infiltrate itself into the soil. If the permeable concrete which has a high porosity is used for the construction of pavements, walking tracks, parking lots, well lining, etc. then it can reduce the runoff from the site and help in the ground water recharge. Such type of smart materials will play an important role for Indian conditions where government is putting lot of efforts to implement ground water recharging techniques. During the research work, the runoff for a particular storm was calculated for a bitumen pavement on a sloping ground. Later after studying the various topographical features, the traffic intensity and the rainfall for that particular area, the concrete was designed and tested for the different proportion and thus the mix design for the permeable concrete was finalized based upon its permeability and strength characteristics. Later by using this permeable concrete the infiltration and runoff for the same storm was compared and studied. The research paper will thus give an account of the properties of permeable concrete where it can be used over an existing road.

  9. NANOMODIFIED CONCRETE

    Directory of Open Access Journals (Sweden)

    B. M. Khroustalev

    2015-01-01

    Full Text Available One of the main directions in construction material science is the development of  next generation concrete that is ultra-dense, high-strength, ultra-porous, high heat efficient, extra corrosion-resistant. Selection of such direction is caused by extreme operational impacts on the concrete, namely: continuously increasing load on the concrete and various dynamics of such loads; the necessity in operation of concrete products in a wide temperature range and their exposure to various chemical and physical effects.The next generation concrete represents high-tech concrete mixtures with additives that takes on and retain the required properties when hardening and being used under any operational conditions. A differential characteristic of the next generation concrete is its complexity that presumes usage of various mineral dispersed components, two- and three fractional fine and coarse aggregates, complex chemical additives, combinations of polymer and iron reinforcement.Design strength and performance properties level of the next generation concrete is achieved by high-quality selection of the composition, proper selection of manufacturing techniques, concrete curing, bringing the quality of concrete items to the required level of technical condition during the operational phase. However, directed formation of its structure is necessary in order to obtain high-tech concrete.Along with the traditional methods for regulation of the next generation concrete structure, modification of concrete while using silica nanoparticles is also considered as a perspective one because the concrete patterning occurs due to introduction of a binder in a mineral matrix. Due to this it is possible to obtain nano-modified materials with completely new properties.The main problem with the creation of nano-modified concrete is a uniform distribution of nano-materials in the volume of the cement matrix which is particularly important in the cases of adding a modifier in

  10. Flexural fatigue characteristics of steel fiber reinforced recycled aggregate concrete (SFRRAC

    Directory of Open Access Journals (Sweden)

    Heeralal M.

    2009-01-01

    Full Text Available This research work is aimed at investigating the flexural fatigue behavior of Steel Fiber Reinforced Recycled Aggregate Concrete (SFRRAC. This study gains importance in view of the wide potential for demolished concrete to serve as a source of quality aggregate feed stock in a variety of structural and non-structural applications. This is a continuation of a series of investigations being conducted aimed at optimizing the utilization of recycled aggregate concrete in rigid pavements. A total of 72 standard flexure specimens of 100mm x 100mm x 450mm were cast and tested for flexure under both static and fatigue loading. The parameters of the investigation included the different replacements of recycled aggregate in natural aggregate, presence of steel fiber and different stress levels. The study showed that the recycled aggregates can be used in rigid pavements also and the inclusion of fibers can benefit the fatigue performance of recycled aggregate concrete.

  11. A STUDY OF BITUMINOUS SHUNGITE BINDER ON THE SCANNING MICROSCOPE

    Directory of Open Access Journals (Sweden)

    K. A. Andrianov

    2012-07-01

    Full Text Available Statement of the problem. It is possible to improve working conditions of road pavement and to use it more efficiently by regulating water-thermal conditions of the subgrade thereby reducing humidity in the design period and mitigating its seasonal changes.Results and conclusions. It is suggested to use extruded foam polystyrene as a heating layer. The thermal fluctuation approach was applied to failure and deformation processes. Physical constants for the analytical description of these processes at varying temperatures and stresses are calculated. The technique for determining acting stresses and temperatures was described. The prediction of the durability of extruded foam polystyrene in road structure is presented.

  12. Design of airport pavements for expansive soils

    Science.gov (United States)

    McKeen, R. G.

    1981-01-01

    Expansive soil subgrades exhibit volume changes with variation in moisture condition. These changes result in differential movement of airport pavements resting on these soils. Special design procedures must be used to account for the expansive soil activity during equilibration. In addition, special precautions are required to protect the subgrade from moisture variation with climate. Measurement of soil suction is a key step in quantifying moisture-induced soil behavior. Procedures are outlined for suction characterization of the soil and for estimating the in situ differential movement likely to occur under the pavement. Once the wavelength and amplitude characteristics of the differential movement are obtained, design calculations to select the thickness and materials for the pavement may proceed.

  13. Patología de pavimentos articulados Pathology of interlocking pavements

    Directory of Open Access Journals (Sweden)

    Carlos Hernando Higuera Sandoval

    2010-07-01

    Full Text Available Este artículo presenta los resultados de un proyecto de grado sobre patología de pavimentos articulados, el cual fue elaborado con el propósito de hacer una recolección de los deterioros típicos de los pavimentos articulados construidos con adoquines de concreto o de ladrillo; y de esta forma, elaborar un catálogo de deterioros para este tipo de estructuras que facilitará la identificación y cuantificación de los deterioros en una inspección visual. El segundo propósito de este proyecto, es la formulación para Colombia de una metodología que permita determinar el Índice de Condición de las estructuras de pavimentos articulados.This article presents the results of a thesis on pathology of interlocking pavements, which objective was to make a compilation of typical damages of interlocking pavements constructed with concrete or brick pavers and, in this way, to elaborate a catalogue of damages for this kind of structures which will make the identification and quantification of deteriorations possible in a visual inspection. The second purpose of this project is the formulation of a methodology which allows determining the Index of pavement conditions for Colombia.

  14. Construction of an experimental sulfur-extended-asphalt pavement

    Science.gov (United States)

    Dodge, K. S.

    1982-07-01

    The design, placement and collection of initial data from a sulfur extended asphalt (SEA) pavement and a conventional pavement used as a control is documented. The SEA pavement used 30 percent sulfur by total weight of the binder. Mix temperatures, hot bin gradations, and toxic emissions were monitored at the plant and the site throughout placement. Aggregates were collected from the hot bin during production of the control and SEA mixes for use in a Marshall mix design. Cores were extracted from both SEA and control pavements 1 month after placement for laboratory testing. Pavement surface properties were also examined after 1 month of service.

  15. Mechanical Characteristic of Pervious Concrete Considering the Gradation and Size of Coarse Aggregates

    OpenAIRE

    Alireza Joshaghani; Ali Akbar Ramezanianpour; Mohammad Jaberizadeh

    2014-01-01

    Pervious concrete is a kind of sustainable pavement with high permeability which is becoming more common as a storm water management. The purpose of this study was to investigate the effects of coarse aggregate on physical and mechanical properties of the pervious concrete such as density, strength, porosity and permeability at 7, 28, 56 days. This experimental investigation conducted by comparing nine different mixtures. Taguchi design of experiments used to optimize the performance of these...

  16. 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.

  17. Comparing Two Methods of Determining Infiltration Rates of Permeable Interlocking Concrete Pavers

    OpenAIRE

    Peter W. B. Nichols; Terry Lucke; Carsten Dierkes

    2014-01-01

    Adequate infiltration through Permeable Interlocking Concrete Pavements (PICPs) is critical to their hydraulic performance. Detected by monitoring infiltration performance, reduced infiltration rates can indicate that maintenance is required. Measurement of infiltration rates has previously been problematic on PICPs because of a lack of accepted standard methodologies and the practical difficulties in modifying existing testing methodologies. On large sites, standard methodologies necessitat...

  18. Damage development in the adhesive zone and mortar of porous asphalt concrete

    NARCIS (Netherlands)

    Mo, L.T.

    2010-01-01

    This research is focused on damage development in the adhesive zone and the mortar of porous asphalt concrete. The motive of this research is the loss of stone from the pavement surface, the so-called ravelling of noise reducing surface wearing courses. Ravelling is the dominant defect of porous asp

  19. Structural Design of Pavement Overlays Based on Functional Parameters

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper reports a practical pavement overlay design methodbased on PCI (Pavement Condition Index). Current pavement investigation method (JTJ 073-96) is compared to the ASTM D 5340, which is the standard test method for airport pavement condition evaluation initially developed for US Air Force. The deficiency in the calculation of PCI based on field data in JTJ 073 is discussed. The proposed design method is compared to AASHTO overlay design method with good agreement. The paper concludes with an example illustrating how the existing pavement structural capacity is related to pavement distress survey results. The presented design method can be used in the design for overlay rehabilitation of pavements of highways, urban streets and airports.

  20. Use of leaching tests to quantify trace element release from waste to energy bottom ash amended pavements.

    Science.gov (United States)

    Roessler, Justin G; Townsend, Timothy G; Ferraro, Christopher C

    2015-12-30

    A series of roadway tests strips were paved on-site at a landfill in Florida, U.S. Waste to energy (WTE) bottom ash was used as a partial course aggregate replacement in a hot mix asphalt (HMA) and a Portland cement concrete (PCC) pavement, along with control HMA and PCC sections. This allowed for a comparison of the relative degree of leaching between both materials (HMA and PCC) as well as between the ash-amended and control pavements. Batch and monolithic tank leaching tests were conducted on the pavements. Testing of the PCC samples demonstrated that Mo and Al were elevated above regulatory thresholds for both the control and ash amended samples. Further leach testing demonstrated that the release of Mo was likely from the PCC and not a result of the inclusion of the BA into pavement. Batch leach testing of ash-amended HMA samples revealed Sb as a constituent of potential concern. The results of the monolith leaching test displayed leaching of Sb within the same order of magnitude as the regulatory threshold. Calculation of the leachability index (LI) for Sb found that it would have limited mobility when incorporated in the HMA matrix. PMID:26340550

  1. Study of thermal reactivity during bituminization of radioactive waste

    International Nuclear Information System (INIS)

    This work deals with the study of chemical reactions and phases transitions which can occur between magnesium nitrate, sodium nitrate, cobalt sulphur product, and nickel potassium ferrocyanide, when they are heated together during bituminization process of nuclear waste. The applied methodology associates a few techniques: temperature, enthalpy, and kinetics of reaction are determined by calorimetry, reaction products are characterised by chemical analyses, mass spectrometry and XRD analysis. Three fields of temperature and energy are observed in function of composition (one compound or a mixture of compounds). The study of reactions between NaNO3 and cobalt sulphur product shows that the presence of water has got an effect on reaction temperature. The study of Mg(NO3)2, 6 H2O and CoS shows an overlapping of different signals, and that the reaction rate is very slow (a few hours). (author)

  2. Leaching tests of simulated Cogema bituminized waste form

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, S.; Akimoto, T.; Iida, Y.; Nagano, T. [Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan)

    2000-07-01

    The leaching behavior of COGEMA-type bituminized radioactive waste was studied for the atmospheric and anaerobic conditions. Active and inactive laboratory-scale bitumen samples, including two major salts of NaNO{sub 3} and BaSO{sub 4}, were contacted with deionized water, an alkaline solution (0.01 mol/L Ca(OH){sub 2} or 0.03 mol/L KOH), or a saline solution (0.5 mol/L KCl). It was found that the release of salt was reduced in the Ca(OH){sub 2} solution compared with deionized water under the atmospheric conditions. No significant difference in the concentrations of {sup 237}Np in leachants contacted with the samples for 7 days was observed between the atmospheric and the anaerobic conditions. (authors)

  3. Steam and air plasma gasification of bituminous coal and petrocoke

    Directory of Open Access Journals (Sweden)

    Vladimir Messerle

    2012-12-01

    Full Text Available This paper presents a numerical analysis and experimental investigation of two very different solid fuels, low-rank bituminous coal of 40 % ash content and petrocoke of 3 % ash content, gasification under steam and air plasma conditions with an aim of producing synthesis gas. Numerical analysis was fulfilled using the software package TERRA for equilibrium computation. Using the results of the numerical simulation, experiments on plasma steam gasification of the petrocoke and air and steam gasification of the coal were conducted in an original installation. Nominal power of the plasma installation is 100 kWe and sum consumption of the reagents is up to 20 kg/h. High quality synthesis gas was produced in the experiments on solid fuels plasma gasification. It has been found that the synthesis gas content at about 97.4 vol.% can be produced. Comparison between the numerical and experimental results showed satisfactory agreement. 

  4. Concrete products

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2002-01-01

    Increased strength and durability in concrete products can be achieved through the addition of fly ash during the manufacturing process. The properties of concrete are enhanced by fly ash. The benefits include cost and the environment. Fly ash is normally defined as finely divided residue resulting from the combustion of pulverized coal, carried from the combustion chamber to the furnace by exhaust gas. The main applications of fly ash in concrete products are ready mix concrete, bridge decks and support footing, precast structures, blocks and bricks, and pipes. The Canadian Standards Association (CSA) has published standards to ensure that the desired physical properties of the concrete are achieved and the standards are found in CSA A23.1, detailing the engineering materials and mix proportions. The type of fly ash to be used for specific properties is important. Finishing and curing operations must be performed with care. The free lime generated by cement hydration reacts with fly ash, forming additional calcium silicate hydrate. Permeability of the concrete is reduced since the calcium silicate hydrate fills the void resulting from the cement pour. Some of the benefits to be derived from fly ash in concrete are: water reduction, improved workability, high ultimate strength, improved pumpability, and reduced heat of hydration. In addition, the life cycle costs are lower, and great strength is obtained. An environmental benefit results from the reduction of natural resource consumption.

  5. 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.

  6. Viscoelastic Pavement Modeling with a Spreadsheet

    DEFF Research Database (Denmark)

    Levenberg, Eyal

    2016-01-01

    The aim herein was to equip civil engineers and students with an advanced pavement modeling tool that is both easy to use and highly adaptive. To achieve this, a mathematical solution for a layered viscoelastic half-space subjected to a moving load was developed and subsequently implemented...

  7. 重载交通下不同基层类型沥青路面结构应力分析%Analysis for Structural Stress of Asphalt Pavement of Different Types of Basecourses under Heavy Load Traffic

    Institute of Scientific and Technical Information of China (English)

    伍祥松

    2012-01-01

    基于我国沥青路面设计理论及标准,参考实际沥青路面结构,选取不同的沥青路面结构与材料参数,如结构层厚度、模量和泊松比等,采用BISAR3.0路面力学计算程序计算分析不同基层类型对沥青混凝土路面结构内部应力状态的影响.结果表明,柔性基层路面与半刚性基层路面的破坏机理存在明显差异,为了实现2种路面的优势互补,应将柔性基层与半刚性基层的结构进行合理的优化组合,以弥补柔性基层和半刚性基层沥青路面的缺陷.%Based on design theories and standards for asphalt pavement in China and by reference to actual structures of asphalt pavement, this paper selects different structure and material parameters of asphalt pavement, such as thickness, modulus and Poisson' s Ratio of structural layers, etc. , calculates and analyzes influences of different basecourse types on internal stress states of asphalt concrete pavement structures by means of BISAR3. 0 mechanical calculation program for pavement. The results show that significant differences exist in failure mechanisms of flexible basecourse pavement and semi - rigid basecourse pavement, to realize complementary advantages of two pavements, the structures of flexible basecourse and semi - rigid basecourse should be optimized and combined in a reasonable way to make up defects of flexible basecourse and semi - rigid basecourse pavements.

  8. Effects of composition and exposure on the solar reflectance of Portland cement concrete

    Energy Technology Data Exchange (ETDEWEB)

    Levinson, Ronnen; Akbari, Hashem

    2001-12-21

    Increasing the solar reflectance (albedo) of a paved surface keeps it cooler in the sun, reducing convection of heat from pavement to air and thereby decreasing the ambient air temperature. Simulations of the influence of pavement albedo on air temperature in Los Angeles predict that increasing the albedo of 1,250 km2 of pavement by 0.25 would save cooling energy worth $15M yr-1, and reduce smog-related medical and lost-work expenses by $76M yr-1. Most sidewalks and a small fraction of roads and parking areas are paved with portland cement concrete, which can be made quite reflective through suitable choice of cement and aggregate. Variations with composition and environmental exposure of the albedos of portland cement concrete pavements were investigated through laboratory fabrication and exposure of 32 mixes of concrete. Twenty-four mixes yielded substandard, ''rough'' concretes due to high, unmet aggregate water demand. The albedos of the remaining eight ''smooth'' concrete mixes ranged from 0.41 to 0.77 (mean 0.59). Simulated weathering, soiling, and abrasion each reduced average concrete albedo (mean decreases 0.06, 0.05, and 0.19, respectively), though some samples became slightly more reflective through weathering or soiling. Simulated rain (wetting) strongly depressed the albedos of concretes (mean decrease 0.23) until their surfaces were dried. Concrete albedo grew as the cement hydration reaction progressed (mean increase 0.08), but stabilized within six weeks of casting. White-cement concretes were on average significantly more reflective than gray-cement concretes. The albedo of the most-reflective white-cement concrete was 0.18 to 0.39 higher than that of the most-reflective gray-cement concrete, depending on state of exposure. Concrete albedo generally correlated with cement albedo and sand albedo, and, after abrasion, with rock albedo. Cement albedo had a disproportionately strong influence on the reflectance

  9. Investigation of the combustion characteristics of Zonguldak bituminous coal using DTA and DTG

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S.; Kucukbayrak, S.; Okutan, H. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2006-06-21

    Combustion characteristics of coking, semicoking, and noncoking Turkish bituminous coal samples from Zonguldak basin were investigated applying differential thermal analysis (DTA) and differential thermogravimetry (DTG) techniques. Results were compared with that of the coke from Zonguldak bituminous coal, a Turkish lignite sample from Soma, and a Siberian bituminous coal sample. The thermal data from both techniques showed some differences depending on the proximate analyses of the samples. Noncombustible components of the volatile matter led to important changes in thermal behavior. The data front both methods were, evaluated jointly, and some thermal properties were interpreted considering these methods in a complementary combination.

  10. Test Study on Fatigue of Combined Structures in Steel Deck Pavement%钢桥面铺装组合结构疲劳试验研究

    Institute of Scientific and Technical Information of China (English)

    李娟; 李玉龙; 吕文捷; 黄辉

    2011-01-01

    桥面铺装是钢桥面行车体系的重要组成部分,桥面铺装质量的好坏直接影响行车的安全性和舒适性.针对"浇筑式沥青混凝土+环氧沥青混凝土"的钢桥面铺装方案,选择更易于引起铺装脱层及开裂的试验加我方法,分别对3种铺装组合结构进行疲劳试验,比较不同组合结构的性能,得出试验结论.试验结果时于大型钢桥面的组合铺装具有借鉴意义.%Deck pavement is an important part of vehicle driving system on steel deck, and the quality of deck pavement has direct impact on safety and comfort of driving. This paper, aiming at the steel deck pavement plan of “east asphalt concrete + epoxy asphalt concrete”, selects an test loading method easy to cause delaminations and cracks of pavement, carries out fatigue test for three combined structures respectively and compare performances of different combined structures, and draws test conclusions. The test results provide a reference for combined pavement of large - sized steel decks.

  11. Maintenance measures for preservation and recovery of permeable pavement surface infiltration rate--The effects of street sweeping, vacuum cleaning, high pressure washing, and milling.

    Science.gov (United States)

    Winston, Ryan J; Al-Rubaei, Ahmed M; Blecken, Godecke T; Viklander, Maria; Hunt, William F

    2016-03-15

    The surface infiltration rates (SIR) of permeable pavements decline with time as sediment and debris clog pore spaces. Effective maintenance techniques are needed to ensure the hydraulic functionality and water quality benefits of this stormwater control. Eight different small-scale and full-scale maintenance techniques aimed at recovering pavement permeability were evaluated at ten different permeable pavement sites in the USA and Sweden. Maintenance techniques included manual removal of the upper 2 cm of fill material, mechanical street sweeping, regenerative-air street sweeping, vacuum street sweeping, hand-held vacuuming, high pressure washing, and milling of porous asphalt. The removal of the upper 2 cm of clogging material did not significantly improve the SIR of concrete grid paves (CGP) and permeable interlocking concrete pavers (PICP) due to the inclusion of fines in the joint and bedding stone during construction, suggesting routine maintenance cannot overcome improper construction. For porous asphalt maintenance, industrial hand-held vacuum cleaning, pressure washing, and milling were increasingly successful at recovering the SIR. Milling to a depth of 2.5 cm nearly restored the SIR for a 21-year old porous asphalt pavement to like-new conditions. For PICP, street sweepers employing suction were shown to be preferable to mechanical sweepers; additionally, maintenance efforts may become more intensive over time to maintain a threshold SIR, as maintenance was not 100% effective at removing clogging material.

  12. Maintenance measures for preservation and recovery of permeable pavement surface infiltration rate--The effects of street sweeping, vacuum cleaning, high pressure washing, and milling.

    Science.gov (United States)

    Winston, Ryan J; Al-Rubaei, Ahmed M; Blecken, Godecke T; Viklander, Maria; Hunt, William F

    2016-03-15

    The surface infiltration rates (SIR) of permeable pavements decline with time as sediment and debris clog pore spaces. Effective maintenance techniques are needed to ensure the hydraulic functionality and water quality benefits of this stormwater control. Eight different small-scale and full-scale maintenance techniques aimed at recovering pavement permeability were evaluated at ten different permeable pavement sites in the USA and Sweden. Maintenance techniques included manual removal of the upper 2 cm of fill material, mechanical street sweeping, regenerative-air street sweeping, vacuum street sweeping, hand-held vacuuming, high pressure washing, and milling of porous asphalt. The removal of the upper 2 cm of clogging material did not significantly improve the SIR of concrete grid paves (CGP) and permeable interlocking concrete pavers (PICP) due to the inclusion of fines in the joint and bedding stone during construction, suggesting routine maintenance cannot overcome improper construction. For porous asphalt maintenance, industrial hand-held vacuum cleaning, pressure washing, and milling were increasingly successful at recovering the SIR. Milling to a depth of 2.5 cm nearly restored the SIR for a 21-year old porous asphalt pavement to like-new conditions. For PICP, street sweepers employing suction were shown to be preferable to mechanical sweepers; additionally, maintenance efforts may become more intensive over time to maintain a threshold SIR, as maintenance was not 100% effective at removing clogging material. PMID:26735865

  13. Development of high stability hot mix asphalt concrete with hybrid binder

    Directory of Open Access Journals (Sweden)

    Toshiaki Hirato

    2014-12-01

    Full Text Available Cost reduction of public works projects has been desired due to severe financial circumstances. Therefore, asphalt pavement has been requested to extend its life. Semi-flexible pavement or epoxy asphalt pavement, which has high rutting resistance and oil resistance, may be applied to the place where these performances ae demanded. However, special technique is required in manufacturing and construction. In addition, these materials have also raised a problem that they cannot be recycled. Meanwhile, conventional asphalt pavement has several drawbacks. It is vulnerable to rutting caused by traffic load and damage caused by petroleum oils such as gasoline or motor oil. The materials used in asphalt mixtures were studied for improving the durability of asphalt mixture. A high stability asphalt concrete was developed which has equal or superior performance to semi-flexible pavement and epoxy asphalt pavement. In this paper, the process of selecting the substance and the characteristics evaluation of the developed mixtures ae described. Furthermore, an inspection result as well as follow-up survey of the performance of the developed mixtures obtained from trial and actual construction is shown.

  14. Effects of conductive fillers on temperature distribution of asphalt pavements

    International Nuclear Information System (INIS)

    The sun provides a cheap and abundant source of clean and renewable energy. Solar cells have been used to capture this energy and generate electricity. A more useful form of the solar cell would be asphalt pavements, which get heated up by solar radiation. Graphite powders are utilized as thermal conductive fillers to make an asphalt collector conductive so as to improve the efficiency of the asphalt collector. Accounting for the important application conditions and evaluating the effects of the heat conductive materials and the solar energy absorbability of the conductive asphalt collector, a finite element model has been developed to predict temperature distributions in the conductive asphalt solar collector. In this study, an experimental validation exercise was conducted using the measured data taken from full-depth asphalt slabs. Validation results showed that the model can satisfactorily predict the temperature distributions in asphalt concrete slabs. The optimal depth is 25-50 mm for placing pipes that serve as the heat exchanger. Meanwhile, the effect of the surroundings on the solar energy potential of the asphalt collector was noticeable.

  15. Effects of conductive fillers on temperature distribution of asphalt pavements

    Science.gov (United States)

    Mingyu, Chen; Shaopeng, Wu; Yuan, Zhang; Hong, Wang

    2010-05-01

    The sun provides a cheap and abundant source of clean and renewable energy. Solar cells have been used to capture this energy and generate electricity. A more useful form of the solar cell would be asphalt pavements, which get heated up by solar radiation. Graphite powders are utilized as thermal conductive fillers to make an asphalt collector conductive so as to improve the efficiency of the asphalt collector. Accounting for the important application conditions and evaluating the effects of the heat conductive materials and the solar energy absorbability of the conductive asphalt collector, a finite element model has been developed to predict temperature distributions in the conductive asphalt solar collector. In this study, an experimental validation exercise was conducted using the measured data taken from full-depth asphalt slabs. Validation results showed that the model can satisfactorily predict the temperature distributions in asphalt concrete slabs. The optimal depth is 25-50 mm for placing pipes that serve as the heat exchanger. Meanwhile, the effect of the surroundings on the solar energy potential of the asphalt collector was noticeable.

  16. State of the art report on bituminized waste forms of radioactive wastes

    International Nuclear Information System (INIS)

    In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

  17. State of the art report on bituminized waste forms of radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Kook; Shon, Jong Sik; Kim, Kil Jeong; Lee, Kang Moo; Jung, In Ha

    1998-03-01

    In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

  18. The shakeout scenario: Meeting the needs for construction aggregates, asphalt, and concrete

    Science.gov (United States)

    Langer, W.H.

    2011-01-01

    An Mw 7.8 earthquake as described in the ShakeOut Scenario would cause significantdamage to buildings and infrastructure. Over 6 million tons of newly mined aggregate would be used for emergency repairs and for reconstruction in the five years following the event. This aggregate would be applied mostly in the form of concrete for buildings and bridges, asphalt or concrete for pavement, and unbound gravel for applications such as base course that goes under highway pavement and backfilling for foundations and pipelines. There are over 450 aggregate, concrete, and asphalt plants in the affected area, some of which would be heavily damaged. Meeting the increased demand for construction materials would require readily available permitted reserves, functioning production facilities, a supply of cement and asphalt, a source of water, gas, and electricity, and a trained workforce. Prudent advance preparations would facilitate a timely emergency response and reconstruction following such an earthquake. ?? 2011, Earthquake Engineering Research Institute.

  19. An Airport Pavement Traffic Simulation Based on CPN

    OpenAIRE

    Heng Hong-jun; Yang Jue

    2014-01-01

    According to the characteristics of airport pavement traffic, we discuss a method of building an airport pavement traffic model which is based on CPN theory and simulate a practical situation as well. The method overcomes the shortage of modelling with normal Petri Net theory, solves the difficult problems of airport pavement traffic such as complex traffic nets, frequent road changing, etc., refines the process of the model, and will be good for the model’s analysis and simulation.

  20. Recent Developments in Pavement Management on Irish National Roads

    OpenAIRE

    Feighan, Kieran; McGowan, Ray; Casey, Tom; O’Sullivan, Andrew

    2015-01-01

    The Irish National pavement network is Ireland’s strategic road network consisting of over 5,300 centreline kilometres of road and is managed by the National Roads Authority (NRA). There is a very significant variation across the network under a variety of headings, including pavement construction, pavement age, carriageway width, lane width, geometric design and traffic volumes carried. A large proportion of the network consists of “legacy” roads that have evolved from historic routes that a...

  1. Permeability testing of drilling core sample from pavement

    Institute of Scientific and Technical Information of China (English)

    Suda WANG; Zhengguang TANG; Xiaojun NING; Peiguan WU; Pingyi XING

    2008-01-01

    The permeability coefficient of pavement material is a very important parameter in designing the drainage of pavement structures and is also used to evalu-ate the quality of road construction. New equipment is used to measure the permeability coefficient of the pave-ment drilling core sample and relevant testing methods are introduced. Testing drilling core samples from a certain highway of Yunnan province has been proven to be feas-ible. The test results are also analyzed.

  2. In-Situ Behavior of Geosynthetically Stabilized Flexible Pavement

    OpenAIRE

    Appea, Alexander Kwasi

    1997-01-01

    The purpose of a geotextile separator beneath a granular base, or subbase in a flexible pavement system is to prevent the road aggregate and the underlying subgrade from intermixing. It has been hypothesized that in the absence of a geotextile, intermixing between base course aggregate and soft subgrade occurs. Nine heavily instrumented flexible pavement test sections were built in Bedford County Virginia to investigate the benefits of geosynthetic stabilization in flexible pavements. ...

  3. Pavement Response to Variable Tyre Pressure of Heavy Vehicles

    OpenAIRE

    Arshad Ahmad Kamil; Haron Hairol Anuar; Abd Rahman Zanariah; Abdul Halim A.G.

    2016-01-01

    In recent years, the effect of overinflated tyre pressure and increased heavy vehicles’ axle load on flexible pavements has become a subject of great concern because of the higher stress levels induced and damage caused to road pavements. This paper aims to evaluate the effect of variable tyre inflation pressures (using actual tyre contact/footprint area) to determine the responses of flexible pavement. A full scale experiment was conducted on a heavy vehicle with 1:1:2 axle configuration, 10...

  4. 路基回弹模量对刚性路面疲劳寿命的影响分析%Effect Analysis of Subgrade Resilient Modulus on Pavement Fatigue Life for Rigid Pavement

    Institute of Scientific and Technical Information of China (English)

    林小平; 凌建明; 周亮

    2012-01-01

    Based on ABAQUS, a 3D finite element model for rigid pavement was established with respect to two types of pavement structures and axle loads, and pavement structural response was calculated with various subgrade resilient modulus. Combined with concrete fatigue function, the effect of subgrade resilient modulus on pavement fatigue life was analyzed. The results indicate that the value of stress in slab bottom and its change rate decrease linearly with the increase of subgrade resilient modulus, while pavement fatigue life and its reduction rate change non-linearly with the increase of subgrade resilient modulus, and pavement fatigue life change more significantly than stress in slab bottom with the variety of subgrade resilient modulus. The pavement fatigue life increase more significantly with the increase of subgrade resilient modulus which in the range of 40~60kPa, and decrease remarkably with the increase of axle load.%基于大型通用有限元软件ABAQUS,建立水泥混凝土路面结构体系三维有限元模型,针对2种路面结构形式和2种轴重的轴载作用,计算不同路基回弹模量下的路面结构响应,结合水泥混凝土疲劳方程,分析路基回弹模量对路面结构疲劳寿命的影响.结果表明,随着路基模量的增加,板底应力水平及变化率近似呈线性水平降低,而路面疲劳寿命与疲劳寿命折减率则呈现出较为明显的非线性变化,应力水平变化不大的条件将使得路面结构疲劳寿命产生显著影响;提高路基回弹模量在较高区间(40~60 kPa)将更加显著增大路面疲劳寿命,另外,增大轴载会使路面结构疲劳寿命显著降低.

  5. 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.

  6. 水泥路面板再生集料基层沥青路面性能预测%Performance Prediction of Recycled Cement Aggregates to Asphalt Pavement Roadbase

    Institute of Scientific and Technical Information of China (English)

    金荣

    2012-01-01

    通过室内试验分析了旧水泥路面板再生集料的技术指标,获取再生集料半刚性基层相关性能.研究结果表明旧水泥路面板再生集料具有良好的路用性能.在此基础上,笔者运用路面设计软件AASHTO 2002 M-E PDG对再生集料半刚性基层沥青路面进行性能预测,讨论新建沥青路面结构组合的可行性,从而为实际工程应用提供理论依据.%The related property of semi-rigid base constructed by recycled aggregates is obtainable through the analysis of the technical indicators on recycled aggregates of the old cement concrete pavement by experiment. The result indicates that the recycled aggregates of old cement concrete pavement remains excellent road performance. And on that basis, with the pavement design software AASHTO 2002 M-E PDG the performance of seme-rigid base asphalt pavement using the material of recycled aggregates is predicted. Moreover, the feasibility of structural composition of new asphalt pavement with an old one has also been discussed which could offer the theory support for the practical engineering application.

  7. Study on Flexible Pavement Failures in Soft Soil Tropical Regions

    Science.gov (United States)

    Jayakumar, M.; Chee Soon, Lee

    2015-04-01

    Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.

  8. Natural gas storage with activated carbon from a bituminous coal

    Science.gov (United States)

    Sun, Jielun; Rood, M.J.; Rostam-Abadi, M.; Lizzio, A.A.

    1996-01-01

    Granular activated carbons ( -20 + 100 mesh; 0.149-0.84 mm) were produced by physical activation and chemical activation with KOH from an Illinois bituminous coal (IBC-106) for natural gas storage. The products were characterized by BET surface area, micropore volume, bulk density, and methane adsorption capacities. Volumetric methane adsorption capacities (Vm/Vs) of some of the granular carbons produced by physical activation are about 70 cm3/cm3 which is comparable to that of BPL, a commercial activated carbon. Vm/Vs values above 100 cm3/cm3 are obtainable by grinding the granular products to - 325 mesh (adsorption capacity increases with increasing pore surface area and micropore volume when normalizing with respect to sample bulk volume. Compared with steam-activated carbons, granular carbons produced by KOH activation have higher micropore volume and higher methane adsorption capacities (g/g). Their volumetric methane adsorption capacities are lower due to their lower bulk densities. Copyright ?? 1996 Elsevier Science Ltd.

  9. Gasification of high ash, high ash fusion temperature bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

    2015-11-13

    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  10. The hydrogasification of lignite and sub-bituminous coals

    Science.gov (United States)

    Bhatt, B.; Fallon, P. T.; Steinberg, M.

    1981-02-01

    A North Dakota lignite and a New Mexico sub-bituminous coal have been hydrogenated at up to 900°C and 2500 psi hydrogen pressure. Yields of gaseous hydrocarbons and aromatic liquids have been studied as a function of temperature, pressure, residence time, feed rates and H2/coal ratio. Coal feed rates in excess of 10 lb/hr have been achieved in the 1 in. I. D.×8 ft reactor and methane concentration as high as 55% have been observed. A four-step reaction model was developed for the production and decomposition of the hydrocarbon products. A single object function formulated from the weighted errors for the four dependent process, variables, CH4, C2H6, BTX, and oil yields, was minimized using a program containing three independent iterative techniques. The results of the nonlinear regression analysis for lignite show that a first-order chemical reaction model with respect to C conversion satisfactorily describes the dilute phase hydrogenation. The activation energy for the initial products formation was estimated to be 42,700 cal/gmole and the power of hydrogen partial pressure was found to be +0.14. The overall correlation coefficient was 0.83. The mechanism, the rate expressions, and the design curves developed can be used for scale-up and reactor design.

  11. Strength Development and Water Permeability of Engineered Biomass Aggregate Pervious Concrete

    Directory of Open Access Journals (Sweden)

    Shahidan S.

    2016-01-01

    Full Text Available Pervious concrete has a high rate of permeability, low strength and high porosity. It is commonly used in the area of storm water management. However, its use has been limited to pavements with low volume traffic. Pervious concrete is different from normal concrete as the mixture contains no fine aggregates. The aggregate is usually of a single size bonded by a cement paste. This study focuses mainly on the effect of Engineered Biomass Aggregate (EBA on the compressive strength and permeability of previous concrete. Three types of mixtures with 0% natural aggregate (NA, 5% BA and 5% of EBA have been studied in this research. A total of 27 150 mm cubes were casted in the laboratory for compressive strength and permeability test. This research aims to enhance the understanding of engineered biomass aggregate pervious concrete as well as the use of pervious concrete for sustainable construction activities due to the environmental benefits it offers.

  12. "Full-Scale Testing of Pavement Response"

    DEFF Research Database (Denmark)

    Ullidtz, Per; Ekdahl, Peter

    1998-01-01

    -analysing FWD data and for calculating the stresses and the strains, the simple method based on Odemark's transformations and Boussinesq's equations appeared to be as good as, or better than, the more sophisticated methods using layered elastic theory or the Finite Element Method.......Three pavement sections in southern Sweden were instrumented in late 1991. Each section have instruments for measuring the strain at the bottom of the asphalt layer, vertical stress and strains in the subgrade and temperatures at different depths. The purpose was to evaluate different theoretical...... methods for determining stresses, strains and deflections in pavement structurers.Falling Weight Deflectometer (FWD) test were done on the test sections, and stresses and strains were measured both under FWD loading and under a rolling wheel load. Different back-analysis procedures were used to derive...

  13. Historic Concrete: From Concrete Repair to Concrete Conservation

    NARCIS (Netherlands)

    Heinemann, H.A.

    2013-01-01

    Concrete like materials were already applied during the Roman Empire. After the decline of the Roman Empire, a wide scale application of concrete only reappeared in the 19th century. Here lies also the origin of modern (reinforced) concrete. Since then, both concrete application and composition have

  14. Towards noise classification of road pavements

    OpenAIRE

    Freitas, Elisabete F.; Paulo, Joel; Coelho, J. L. Bento; Pereira, Paulo A. A.

    2008-01-01

    Noise classification of road surfaces has been addressed in many European countries. This paper presents the first approach towards noise classification of Portuguese road pavements. In this early stage, it aims at establishing guidelines for decision makers to support their noise reduction policies and the development of a classification system adapted to the European recommendations. A ranking to provide guidance on tire-road noise emission levels for immediate use by decisio...

  15. Smart pavement sensor based on thermoelectricity power

    Science.gov (United States)

    Yu, Xiong; Zhang, Bin; Tao, Junliang; Liu, Zhen

    2010-04-01

    The aging infrastructure requires a proactive strategy to ensure their functionality and performance. Innovative sensors are needed to develop infrastructures that are intelligent and adaptive. A power supply strategy is among the crucial components to reduce the instrument cost and to ensure the long term function of these embedded sensors. This paper introduces the results of a preliminary study on using thermo-electricity generation to power sensors. This presents an innovative strategy for long term monitoring of pavement performance.

  16. The optimization of concrete mixtures for use in highway applications

    Science.gov (United States)

    Moini, Mohamadreza

    Portland cement concrete is most used commodity in the world after water. Major part of civil and transportation infrastructure including bridges, roadway pavements, dams, and buildings is made of concrete. In addition to this, concrete durability is often of major concerns. In 2013 American Society of Civil Engineers (ASCE) estimated that an annual investment of 170 billion on roads and 20.5 billion for bridges is needed on an annual basis to substantially improve the condition of infrastructure. Same article reports that one-third of America's major roads are in poor or mediocre condition [1]. However, portland cement production is recognized with approximately one cubic meter of carbon dioxide emission. Indeed, the proper and systematic design of concrete mixtures for highway applications is essential as concrete pavements represent up to 60% of interstate highway systems with heavier traffic loads. Combined principles of material science and engineering can provide adequate methods and tools to facilitate the concrete design and improve the existing specifications. In the same manner, the durability must be addressed in the design and enhancement of long-term performance. Concrete used for highway pavement applications has low cement content and can be placed at low slump. However, further reduction of cement content (e.g., versus current specifications of Wisconsin Department of Transportation to 315-338 kg/m 3 (530-570 lb/yd3) for mainstream concrete pavements and 335 kg/m3 (565 lb/yd3) for bridge substructure and superstructures) requires delicate design of the mixture to maintain the expected workability, overall performance, and long-term durability in the field. The design includes, but not limited to optimization of aggregates, supplementary cementitious materials (SCMs), chemical and air-entraining admixtures. This research investigated various theoretical and experimental methods of aggregate optimization applicable for the reduction of cement content

  17. Concrete Memories

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    2015-01-01

    and poetic appropriations and inscriptions of the bunker site are depicted. Ranging between overlooked side presences and an overwhelming visibility, the concrete remains of fascist war architecture are involved in and motivate different sensuous experiences and mnemonic appropriations. The article meets...

  18. Bituminous reference document: synthesis of knowledge on the long time behavior of bituminous packages; Dossier de reference bitume: synthese des connaissances sur le comportement a long terme des colis bitumes

    Energy Technology Data Exchange (ETDEWEB)

    Sercombe, J.; Adenot, F.; Vistoli, P.P.; Parraud, S.; Riglet-Martial, C.; Gwinner, B.; Felines, I.; Tiffreau, C.; Libert, M

    2004-07-01

    This document is a synthesis of the knowledge acquired at the CEA on the behavior of bituminous packages. In this framework, the CEA studied bituminous packages in generic conditions of a package lifetime. The main factors, the evolution mechanisms and influential parameters have been determined and quantitative s simulation have been developed. After a description of the main initial bituminous packages characterizations, the evolutions in saturated and un-saturated environment are exposed. (A.L.B.)

  19. New structural systems for zero-maintenance pavements. Volume 2: Analysis of anchored pavements using ANSYS

    Science.gov (United States)

    Saxena, S. K.; Militsopoulos, S. G.

    1980-08-01

    A set of procedures to evaluate the response of an anchored pavement subjected to vehicle static loads, moisture variation in the subgrade, and/or temperature variation through the surface of the pavement is presented. These procedures include two computer programs known as FEMESH and ANSYS. The FEMESH program generates rectangular meshes in either a two or three dimensional coordinate system for any prespecified number and spacing of nodes. The ANSYS program evaluates the stresses, strains, and the deflections at all elements in each material included in the analytical model.

  20. Sulfur concrete for haul road construction at Suncor oil sands mines

    Energy Technology Data Exchange (ETDEWEB)

    Abraha, D.G. [Thurber Engineering Ltd., Calgary, AB (Canada); Sego, D.C.; Biggar, K.W.; Donahue, R. [Alberta Univ., Edmonton, AB (Canada). Geotechnical Center; Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2007-05-15

    Properly constructed haul roads are needed to ensure the efficient use of ultra large haul trucks used at oil sand mining operations in northern Alberta. The haul roads at Suncor are presently constructed with crushed limestone, gravel, lean oil sand and till. The roads deteriorate significantly during the summer months due to material softening. A study was therefore conducted to determine the feasibility of building mine haul roads at Suncor oil sand mines using concrete prepared from by-products and mine wastes such as sulfur, fly ash, coke and tailings sand. The physical and mechanical properties of various mixes of sulfur concrete were characterized in laboratory studies involving compression measuring and split tensile and freeze thaw durability tests. The geochemical interaction of sulfur concrete with the near surface environment was also investigated with reference to the operational life of the haul road and interaction of sulfur concrete with ground water. A haul road test section was designed based on the resilient modulus design method. A finite element analysis was used to calculate the stress and strain distributions in the road caused by truck tires. The pavement thickness was determined based on the truck loads, the resilient modulus and the strength of the sulfur concrete and subgrade material. It was concluded that sulfur concrete produced from mine wastes is significantly stronger and stiffer than the existing haul road material. Therefore, better haul roads can be constructed with reduced pavement thicknesses using tailing sand sulfur concrete. 8 refs., 4 tabs., 14 figs.

  1. An analysis of pavement heat flux to optimize the water efficiency of a pavement-watering method

    International Nuclear Information System (INIS)

    Pavement-watering as a technique of cooling dense urban areas and reducing the urban heat island effect has been studied since the 1990's. The method is currently considered as a potential tool for and climate change adaptation against increasing heat wave intensity and frequency. However, although water consumption necessary to implement this technique is an important aspect for decision makers, optimization of possible watering methods has only rarely been conducted. An analysis of pavement heat flux at a depth of 5 cm and solar irradiance measurements is proposed to attempt to optimize the watering period, cycle frequency and water consumption rate of a pavement-watering method applied in Paris over the summer of 2013. While fine-tuning of the frequency can be conducted on the basis of pavement heat flux observations, the watering rate requires a heat transfer analysis based on a relation established between pavement heat flux and solar irradiance during pavement insolation. From this, it was found that watering conducted during pavement insolation could be optimized to 30-min cycles and water consumption could be reduced by more than 80% while reducing the cooling effect by less than 13%. - Highlights: • The thermal effects of pavement-watering were investigated in Paris, France. • Pavement-watering was found to significantly affect pavement heat flux 5 cm deep. • When insolated, a linear relation was found between heat flux and solar radiation. • Pavement-watering did not alter its slope, but introduced a negative intercept. • Subsequent improvements of the watering period, frequency and rate are proposed

  2. Evaluation of Permeability of Asphalt Pavement Based on Differential Thermal Infrared of Pavement Surface%基于路表红外差热的沥青混凝土路面渗水性能评价

    Institute of Scientific and Technical Information of China (English)

    李志栋; 黄晓明; 赵洁雯; 郭辉; 许涛; 陈广秀

    2012-01-01

    因离析、荷载、自然等因素的影响,沥青混凝土路面产生密实性不均一以及渗水性能表面差异性,为了改变目前渗水仪检测效率低、代表性差等现状,能够快速、多剖面对其渗水性能进行检测评价.首先,通过试验与有限元方法分析了沥青混凝土路面表面温度及其差异度与其渗水性能的相关性;同时,优选了路表温度差异度的最佳检测方法.研究表明:路表温度差异度与渗水性能相关系数达到0.9747,与传统渗水仪的渗水系数相关性达0.8272,建立了通过红外识别路表温度差异度来检测沥青混凝土路面渗水性能的方法和相应评价标准.另外,开发了连续测速达100 km/h的沥青混凝土路面渗水性红外检测仪,与传统渗水仪相比,检测范围由点变面,效率提高80倍,费用节约58%,并与处治透水的雾封层技术实现数据信息共享.%Because of synthesis effect of the segregation, loads and climate, the densification and permeability of the surface of asphalt concrete pavement is different. To change the status that the detecting efficiency and veracity of permeability detector at present is low and the permeability can be detected quickly and multi-section,firstly, the relativity between the surface temperature difference degree and permeability of asphalt concrete pavement is analyzed by the laboratory experiments and ABAQUS elements, and the detecting way of temperature difference degree optimized. It proved that relativity of the surface temperature difference degree and permeability of asphalt concrete pavement or permeability coefficient by the permeability detector arrived to 0. 974 7 or 0. 827 2, and detecting way of asphalt concrete pavement permeability is established based on the surface temperature difference degree identified by the infrared technology. At the same time, based on this principle the first continuous infrared detector reached l00km/h ,of asphalt concrete pavement

  3. Modeling the Hydrologic Processes of a Permeable Pavement System

    Science.gov (United States)

    A permeable pavement system can capture stormwater to reduce runoff volume and flow rate, improve onsite groundwater recharge, and enhance pollutant controls within the site. A new unit process model for evaluating the hydrologic performance of a permeable pavement system has be...

  4. Nutrient Infiltrate Concentrations from Three Permeable Pavement Types

    Science.gov (United States)

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha...

  5. 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,…

  6. Research on pavement crack recognition methods based on image processing

    Science.gov (United States)

    Cai, Yingchun; Zhang, Yamin

    2011-06-01

    In order to overview and analysis briefly pavement crack recognition methods , then find the current existing problems in pavement crack image processing, the popular methods of crack image processing such as neural network method, morphology method, fuzzy logic method and traditional image processing .etc. are discussed, and some effective solutions to those problems are presented.

  7. Nuclear method for determination of asphalt content corrected for moisture in bituminous mixture. Final report, March 1988-February 1989

    International Nuclear Information System (INIS)

    This report presents results of research on the development of a method for determination of asphalt content corrected for moisture using the nuclear-gauge method. The researchers selected an approach that involved rapid drying of the asphalt concrete samples in a microwave oven prior to the determination of asphalt content using a Troxler Model 3241-C nuclear asphalt-content gauge. As a reference, asphalt contents were also measured using quantitative extraction. In general, good agreement was found between asphalt contents measured by the Troxler Model 3241-C nuclear gauge and asphalt contents measured by quantitative extraction. In extended sampling for Plant 1, no significant increase in nuclear gauge error was seen over a 10-day sampling period, which indicates that daily calibration of the nuclear gauge is probably unnecessary to maintain satisfactory performance. The field demonstration of the procedure of drying the bituminous mixture in a microwave oven and then determining its asphalt content by the nuclear method indicated asphalt-content results were obtained approximately 1 hour faster than results obtained by quantitative extraction

  8. Modelling of the fracture toughness anisotropy in fiber reinforced concrete

    Directory of Open Access Journals (Sweden)

    S. Tarasovs

    2016-01-01

    Full Text Available Steel fiber reinforced concrete is potentially very promising material with unique properties, which currently is widely used in some applications, such as floors and concrete pavements. However, lack of robust and reliable models of fiber reinforced concrete fracture limits its application as structural material. In this work a numerical model is proposed for predicting the crack growth in fiber reinforced concrete. The mixing of the steel fibers with the concrete usually creates nonuniform fibers distribution with more fibers oriented in horizontal direction, than in vertical. Simple numerical models of fiber reinforced concrete require a priori knowledge of the crack growth direction in order to take into account bridging action of the fibers, which depends on the fibers orientation. In proposed model user defined elements are used to calculate the bridging force during the course of the analysis when the crack starts to grow. Cohesive elements were used to model the crack propagation in the concrete matrix. In cohesive zone model the cohesive elements are embedded between all solid elements to simulate the arbitrary crack path. The bridging effect of the fibers are modeled as nonlinear springs, where the stiffness of the springs is defined from experimentally measured pull-out force and the angle between the fiber and crack opening direction.

  9. Monitoring asphalt pavement damages using remote sensing techniques

    Science.gov (United States)

    Mettas, Christodoulos; Themistocleous, Kyriacos; Neocleous, Kyriacos; Christofe, Andreas; Pilakoutas, Kypros; Hadjimitsis, Diofantos

    2015-06-01

    One of the main issues in the maintenance plans of road agencies or governmental organizations is the early detection of damaged asphalt pavements. The development of a smart and non-destructive systematic technique for monitoring damaged asphalt pavements is considered a main priority to fill this gap. During the 1970's, remote sensing was used to map road surface distress, while during the last decade, remote sensing became more advanced, thereby assisting in the evolution of the identification and mapping of roads. Various techniques were used in order to explore condition, age, weaknesses and imperfections of asphalted pavements. These methods were fairly successful in the classification of asphalted surfaces and in the detection of some of their characteristics. This paper explores the state of the art of using remote sensing techniques for monitoring damaged pavements and some typical spectral profiles of various asphalt pavements in Cyprus area acquired using the SVC1024 field spectroradiometer.

  10. MECHANICAL ANALYSIS OF PAVEMENT ON GFRP BRIDGE DECK%GFRP桥面铺装力学性能研究

    Institute of Scientific and Technical Information of China (English)

    朱坤宁; 万水

    2011-01-01

    GFRP桥面铺装是GFRP桥面板组合梁桥行车体系的重要组成部分.本文采用有限元分析软件对车辆荷载作用下GFRP桥面铺装层的应力分布情况进行了分析,得到了计算铺装层最大拉应力的控制荷位,并计算了在此荷位下GFRP桥面铺装层中的应力水平.研究了GFRP桥面铺装层中的应力、应变分布规律.根据分析结果,提出了大广高速6号跨线桥及类似GFRP桥面铺装的设计指标.%Pavement on GFRP bridge deck is an important part in vehicle system. The distribution of stress in the pavement is analysed with FEM software. The controlling load position is found and the stress in the pavement is computed under the load position. The distribution of the stress and strain in the asphalt concrete surfacing is stud ied. Based on analysis results, the design indexes of the No. 6 flyover bridge of Daguang Highway are proposed.

  11. 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.

  12. 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.

  13. Study on Surface Heat Budget of Various Pavements for Urban Heat Island Mitigation

    Directory of Open Access Journals (Sweden)

    Hideki Takebayashi

    2012-01-01

    Full Text Available The surface heat budgets of various pavement surfaces are studied with the aim of mitigating the urban heat island effect. In this study, the thermal characteristics of pavements are examined using data from observations. The net radiation, surface temperature, temperature under the surface, conduction heat flux, and core weight for each experimental surface are recorded, together with the weather conditions at the time of observation. The latent heat flux is estimated from the observed weight of the cores. The surface heat budget under the same weather conditions is examined, and the sensible heat flux from each target surface is calculated. The parameters that influence the surface heat budget, for example, solar reflectance (albedo, evaporative efficiency, heat conductivity, and heat capacity, are examined. On a typical summer day, the maximum reduction in the sensible heat flux from that on a normal asphalt surface is about 150 W/m2 for an asphalt surface with water-retaining material and about 100 W/m2 for a cement concrete surface with water-retaining material, depending on the albedo of each surface.

  14. Diurnal Thermal Behavior of Pavements, Vegetation, and Water Pond in a Hot-Humid City

    Directory of Open Access Journals (Sweden)

    Xiaoshan Yang

    2015-12-01

    Full Text Available This study investigated the diurnal thermal behavior of several urban surfaces and landscape components, including pavements, vegetation, and a water pond. The field experiment was conducted in a university campus of Guangzhou, South China, which is characterized by a hot and humid summer. The temperature of ground surface and grass leaves and the air temperature and humidity from 0.1 to 1.5 m heights were measured for a period of 24 h under hot summer conditions. The results showed that the concrete and granite slab pavements elevated the temperature of the air above them throughout the day. In contrast, the trees and the pond lowered the air temperature near ground during the daytime but produced a slight warming effect during the nighttime. The influence of vegetation on air temperature and humidity is affected by the configurations of greenery. Compared to the open lawn, the grass shaded by trees was more effective in cooling and the mixture of shrub and grass created a stronger cooling effect during the nighttime. The knowledge of thermal behavior of various urban surfaces and landscape components is an important tool for planners and designers. If utilized properly, it can lead to climatic rehabilitation in urban areas and an improvement of the outdoor thermal environment.

  15. Development of Paving Material for Footpath and CAR Park Pavement Using Granite Soil

    Science.gov (United States)

    Nagamachi, Masaharu; Mizuguchi, Hiroyuki; Inoue, Kentaro; Kamada, Koichi

    It is required to develop new paving materials for pavements, such as footpaths, car parks, etc., in parks, having good landscape. Such paving materials have been already developed, but these do not have sufficient strength, abrasion resistance and frost resistance. In this study, a new paving was examined material using cement, sand and granite soil. The mix proportion of this material tested was 2:4:4 of cement, sand and granite soil by mass. The maximum flexural and compressive strength were both obtained at a water content of 14% of the total mass, and the strength were several times larger than that of paving material on the market consisting of 10% of cement and 90% granite soil. The abrasion resistance was tested according to ASTM C 779, and this resistance was about four times greater than that of the paving material on the market. The frost resistance was obtained high value compared with the concrete of 72% in water cement ratio by a new simple resisting test method for freezing and thawing using liquid nitrogen and warm water. It is considered that this new paving material is applicable to pavement for footpath, car park, etc.

  16. Performance of an enhanced pervious pavement system loaded with large volumes of hydrocarbons.

    Science.gov (United States)

    Newman, Alan P; Puehmeier, Tim; Shuttleworth, Andy; Pratt, Christopher J

    2014-01-01

    Five litres of lubricating oil and two 8.5 litre batches of diesel were deposited on each of two hydraulically isolated experimental enhanced pervious pavement parking bays. The 50 mm aggregate subbases of the two bays were of either recycled concrete or crushed limestone. The bays were constructed in such a way that a near-surface gravity separator was created by the arranging of the outlet pipes such that a permanent pool of water was maintained in the system and water could only enter from below the level of any floating oil. Dissolved/dispersed hydrocarbons were measured at acceptable concentrations when monitoring was carried out over a period of approximately 5 months. The maximum concentration was 7.2 mg/l and of all the samples collected only 3% exceeded the 5 mg/l limit applied in the UK for a class 1 interceptor, and the majority of samples had hydrocarbon concentrations of less than 2 mg/l. Much more significant is the fact that no free product was discharged from either system up to the time the experiment was dismantled 2 years from the first oil application despite the fact that sufficient hydrocarbon had been added to each pavement to produce a film on a water surface of over 500 hectares. PMID:25225930

  17. Pavement Pre- and Post-Treatment Performance Models Using LTPP Data

    OpenAIRE

    Lu, Pan; Tolliver, Denver

    2012-01-01

    This paper determines that pavement performance in International Roughness Index (IRI) is affected by exogenous interventions such as pavement age, precipitation level, freeze-thaw level, and lower level preservation maintenance strategies. An exponential function of pavement age was used to represent pavement IRI performance curves. Moreover, this paper demonstrates a method which calculates short-term post-pavement performance models from maintenance effect models and pre-treatment performa...

  18. Measurement of the Cooling Efficiency of Pavement-Watering as an Urban Heat Island Mitigation Technique

    Directory of Open Access Journals (Sweden)

    Martin Hendel

    2015-03-01

    Pavement watering was found to lower pavement surface temperatures by several degrees for several hours after watering, while also strongly reducing its cooling rate a few hours before and after sunset. Heat flux and storage at a depth of 5 cm in the pavement were also found to have been significantly reduced, especially during direct sunlight exposure, but also when the pavement was in the shade. Uninterrupted watering appears necessary during direct sunlight exposure of the pavement to maximize efficiency.

  19. Tire Footprint Affects Hydroplaning On Wet Pavement

    Science.gov (United States)

    Yager, Thomas J.

    1989-01-01

    Recent investigations of tire hydroplaning at highway speeds reveal, in addition to inflation pressure, tire-footprint aspect ratio (FAR), defined as width divided by length of tire surface in contact with pavement, significantly influences speed at which dynamic hydroplaning begins. Tire speeds and forces developed during tests of up to 65 mi/h (105 km/h) were monitored on flooded test surface to identify development of hydroplaning. Study focused on automotive tires because FAR's of automotive tires vary more than those of aircraft tires.

  20. Global market trade policy analysis for petroleum oils and oils obtained from bituminous minerals, crude

    Directory of Open Access Journals (Sweden)

    Bagheri, F.

    2012-01-01

    Full Text Available This article is based on surveying the custom tariffs imposed on the world export market of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. We obtained the data according to the most updated available data provided online by UNCTAD and World Bank. The results indicate that none of the 142 countries in the world market of this product have imposed non-tariff trade barriers on the import of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. The developed countries and the countries with transition economies are the main world import partners. European Union, United States, China, Japan, South Korea, Canada, Singapore, Taiwan, Thailand, South Africa, Australia, Turkey, Brazil, Sweden and Belarus are the examples and have imposed low custom tariffs on Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude.

  1. The application research of new asphalt pavement structures in China%新型沥青路面结构在我国的应用研究

    Institute of Scientific and Technical Information of China (English)

    刘军霞

    2014-01-01

    This paper summarized and analyzed the existing problems of flexible base,composite base asphalt pavement structure in highway con-struction application,researched the technical measures to strengthen the new asphalt pavement structure performance,and discussed the low noise asphalt pavement,asphalt concrete cover surface technology,waterproof layer technology and other new technology,so as to enhance the use per-formance of asphalt pavement.%对柔性基层、组合式基层沥青路面结构在公路建设应用中存在的问题进行了总结分析,研究了加强新型沥青路面结构性能的技术措施,并对低噪声沥青路面、沥青混凝土罩面技术、防水层技术等新型技术作了论述,以不断提高沥青路面的使用性能。

  2. 钢桥面组合铺装结构性能研究%Research on Structural Performances of Combined Pavement on Steel Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    伍朝晖; 张峰; 郝增恒

    2011-01-01

    通过对包括沥青混凝土的3种组合铺装结构高温稳定性能、低温弯曲性能、疲劳性能以及防水材料性能的综合研究,对比环氧沥青与浇筑式组合结构、与双层环氧铺装结构的性能差异,通过试验验证不同类型的组合铺装结构作为钢桥面铺装的技术性能,提出组合铺装结构作为钢桥面铺装的建议.%Based on a comprehensive research on performance of high-temperature stability, performance of low-temperature bending, fatigue performance and performance of water-proof materials of three combined pavement structures including asphalt concrete, and comparison of performance deviations between epoxy asphalt & casting combined structure and double-layer epoxy pavement structure, this paper verifies technical properties of different types of combined pavement structures on steel bridge deck via test, and puts forward suggestions of combined pavement structures adopted for steel bridge deck.

  3. In-situ infiltration performance of different permeable pavements in a employee used parking lot--A four-year study.

    Science.gov (United States)

    Kumar, Kuldip; Kozak, Joseph; Hundal, Lakhwinder; Cox, Albert; Zhang, Heng; Granato, Thomas

    2016-02-01

    Permeable pavements are being adopted as a green solution in many parts of the world to manage urban stormwater quantity and quality. This paper reports on the measured in-situ infiltration performance over a four-year period since construction and use of three permeable parking sections (permeable pavers, permeable concrete and permeable asphalt) of an employee car parking lot. There was only a marginal decline in infiltration rates of all three pavements after one year of use. However, between years two to four, the infiltration rates declined significantly due to clogging of pores either by dry deposition of particles and/or shear stress of vehicles driving and degrading the permeable surfaces; during the last two years, a greater decline was also observed in driving areas of the parking lots compared to parking slots, where minimal wear and tear are expected. Maintenance strategies were employed to reclaim some of the lost infiltration rate of the permeable pavements to limited success. Despite this decline, the infiltration rates were still four to five times higher than average rainstorm intensity in the region. Thus, these permeable pavement parking lots may have significant ecological importance due to their ability to infiltrate rainwater quickly, reduce the runoff in the catchment area, and also dampen runoff peak flows that could otherwise enter the collection system for treatment in a combined sewer area.

  4. In-situ infiltration performance of different permeable pavements in a employee used parking lot--A four-year study.

    Science.gov (United States)

    Kumar, Kuldip; Kozak, Joseph; Hundal, Lakhwinder; Cox, Albert; Zhang, Heng; Granato, Thomas

    2016-02-01

    Permeable pavements are being adopted as a green solution in many parts of the world to manage urban stormwater quantity and quality. This paper reports on the measured in-situ infiltration performance over a four-year period since construction and use of three permeable parking sections (permeable pavers, permeable concrete and permeable asphalt) of an employee car parking lot. There was only a marginal decline in infiltration rates of all three pavements after one year of use. However, between years two to four, the infiltration rates declined significantly due to clogging of pores either by dry deposition of particles and/or shear stress of vehicles driving and degrading the permeable surfaces; during the last two years, a greater decline was also observed in driving areas of the parking lots compared to parking slots, where minimal wear and tear are expected. Maintenance strategies were employed to reclaim some of the lost infiltration rate of the permeable pavements to limited success. Despite this decline, the infiltration rates were still four to five times higher than average rainstorm intensity in the region. Thus, these permeable pavement parking lots may have significant ecological importance due to their ability to infiltrate rainwater quickly, reduce the runoff in the catchment area, and also dampen runoff peak flows that could otherwise enter the collection system for treatment in a combined sewer area. PMID:26606196

  5. Computational Modelling in Development of a Design Procedure for Concrete Road

    Directory of Open Access Journals (Sweden)

    B. Novotný

    2000-01-01

    Full Text Available The computational modelling plays a decisive part in development of a new design procedure for concrete pavement by quantifying impacts of individual design factors. In the present paper, the emphasis is placed on the modelling of a structural response of the jointed concrete pavement as a system of interacting rectangular slabs transferring wheel loads into an elastic layered subgrade. The finite element plate analysis is combined with the assumption of a linear contact stress variation over triangular elements of the contact region division. The linking forces are introduced to model the load transfer across the joints. The unknown contact stress nodal intensities as well as unknown linking forces are determined in an iterative way to fulfil slab/foundation and slab/slab contact conditions. The temperature effects are also considered and space is reserved for modelling of inelastic and additional environmental effects. It is pointed out that pavement design should be based on full data of pavement stressing, in contradiction to procedures accounting only for the axle load induced stresses.

  6. A Study on the Properties and Chloride Resistance of Modified Sulfur Concrete for Nuclear Power Plant and Marine Structures

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Soon Myun; Chang, Hyun Young; Park, Heung Bae [KEPCO EnC, Seongnam (Korea, Republic of)

    2015-05-15

    The mechanical, physical and chemical properties of concrete with modified sulfur have been compared and assessed against ordinary concrete. As its excellent chloride resistance and extended service life have been verified, the technology to apply modified sulfur to the construction of nuclear power plant and marine structures has been developed and secured. Recently, modified sulfur concrete has been applied for road pavement and repair works in more than 20 sites including highway and airport in Korea. Also, in the U.S., Federal Highway Administration and Virginia Department of Transportation are implementing tests to apply modified sulfur to bridge road pavement, and the modified sulfur concrete has been recognized for its good performance. Based on these cases, this study carried out tests on physical, mechanical and chemical properties of concrete after adding modified sulfur by building concrete specimens based on the concrete mix design employed to construct the Shin-Kori Units 3 and 4 containment building. Multiple tests were performed particularly for chemical resistance, a factor directly related to concrete service life. As a result, it has been verified that concrete with 5% modified sulfur content relative to cement weight has equal mechanical properties (compressive strength, tensile strength, etc.) and much better workability (slump change) and chemical resistance (resistance to chloride ion penetration, concrete carbonation) compared with ordinary concrete. Based on this, it has been concluded that an addition of modified sulfur can double the service life of concrete. In general, studies demonstrate that a significant amount of slag should be mixed into concrete to raise chemical resistance (but with decreasing mechanical properties). Considering this, this study is unparalleled.

  7. Safety assessment for the bituminization facility of the medium-level waste

    International Nuclear Information System (INIS)

    The safety assessment for the home-made bituminization facility of the medium-level waste during hot test is made. The average external dose equivalent per month is 0.136 x 10-2 Sv. The radioactive substance released into the environment is much lower than the permissible limit. The danger of burning and exploding of the bituminized product is avoided because the operation temperature is controlled strictly below 170 C degree. The report also briefly describes the structural characteristic of the facility, the main process and radiation protection and safety measures

  8. Project and design of apparatus and equipment of pilot plant experimental bituminization line PS 44 EBO

    International Nuclear Information System (INIS)

    The modifications are described made in the design of major components of the pilot plant experimental bituminization line involving: the mixing equipment, the film rotor evaporator, the calciner, and various transport mechanisms for handling drums and containers. The difficulty and complexity of the problem which Kralovopolska strojirna Brno, the end supplier of the bituminization line, will have to tackle is evident mainly from the case of bridge cranes, which feed the line, and the full-portal gantry crane which handles the containers and drums at regional sites of radioactive waste disposal. (Z.M.)

  9. Installation in the A-1 plant of an experimental bituminization line by VUCHZ

    International Nuclear Information System (INIS)

    Following the termination of the experimental operation of the bituminization line at the Research Institute for Chemical Installations in Brno, the line was dismantled and transferred to the nucler power plant in Jaslovske Bohunice. The installation of the line, the layout of the assemblies are described and the results of tests with non-radioactive simulated wastes and actual radioactive wastes briefly described. An amount of 3.2 m3 of actual radioactive wastes from the V-1 nuclear power plant was processed in the tests. The results confirmed the suitability of bituminization for processing liquid radioactive wastes from WWER nuclear power plants. (Z.M.)

  10. Survival Analysis of Fatigue and Rutting Failures in Asphalt Pavements

    Directory of Open Access Journals (Sweden)

    Pabitra Rajbongshi

    2016-01-01

    Full Text Available Fatigue and rutting are two primary failure mechanisms in asphalt pavements. The evaluations of fatigue and rutting performances are significantly uncertain due to large uncertainties involved with the traffic and pavement life parameters. Therefore, deterministically it is inadequate to predict when an in-service pavement would fail. Thus, the deterministic failure time which is known as design life (yr of pavement becomes random in nature. Reliability analysis of such time (t dependent random variable is the survival analysis of the structure. This paper presents the survival analysis of fatigue and rutting failures in asphalt pavement structures. It is observed that the survival of pavements with time can be obtained using the bathtub concept that contains a constant failure rate period and an increasing failure rate period. The survival function (S(t, probability density function (pdf, and probability distribution function (PDF of failure time parameter are derived using bathtub analysis. It is seen that the distribution of failure time follows three parametric Weibull distributions. This paper also works out to find the most reliable life (YrR of pavement sections corresponding to any reliability level of survivability.

  11. An Innovative Strategy for Maintenance of Highway Pavement

    Directory of Open Access Journals (Sweden)

    Sandeep Choudhary, Dr. P. K. Agarwal

    2013-05-01

    Full Text Available Highway pavement are deteriorating fast due to lack of timely maintenance, leading to higher vehicle operating costs, increasing number of accidents etc. Thus, timely maintenance of the highway pavement is essential. Because, once pavements start to deteriorate; they deteriorate rapidly beyond the point where maintenance is effective. Thus, there is an urgent need to develop a strategy for maintenance of pavement in a huge highway network. In this study, an innovative strategy for maintenance of highway pavement is proposed. A two stage maintenance strategy is proposed. In stage I, it is proposed to determine priority of highway sections. In Stage II, priority of various maintenance activities to be carried out on various sections will be determined. Maintenance priority of the pavement is based on importance of the road sections, present road conditions, and future road conditions. The methodology proposed in this study is illustrated with the help of example of some hypothetical highway network consisting of 4 sections. Analysis results indicated that the proposed strategy is considered to be more rational, innovative & logical. Some strategies for maintenance of urban roads are also presented in this study. Therefore, it is expected that this study will be useful for maintenance of huge highway network in India and thus will be useful for preserving huge asset of pavement infrastructure.

  12. Experimental Study of Recycling of Waste Concrete Cement Pavement in Semi-rigid Base Course%废弃水泥混凝土道面在路面半刚性基层中再生利用的试验研究

    Institute of Scientific and Technical Information of China (English)

    单双成; 陈满

    2013-01-01

    It is an important problem to make effective use of scrap concrete material during maintenance or reconstruction of a cement concrete road.By studying the waste concrete crushed and screened some results were obtained that the recycled aggregate contained water of crystallization which would affect the optimal amount of water and the determination of the maximum dry density.Recycled coarse aggregate and natural gravel had quite mechanical properties.Cement stabilized recycled mixtures' design were did and performance tests found that cement stabilized recycled aggregate has good strength,frost resistance,water stability.It had similar resilient modulus with cement stabilized natural aggregate and poor performance anti-shrinkage deformation.Control regeneration mixing amount of fine aggregate can be very good to meet the requirements of the semi-rigid base material.%水泥混凝土道路改建时形成的废弃混凝土块的有效利用是一个亟待解决的问题.通过对破碎、筛分后的废弃混凝土性能研究发现:再生料中含有部分结晶水,会影响最佳用水量和最大干密度的确定;再生粗集料和天然碎石具有相当的力学性能.对水泥稳定再生集料进行了配合比设计,并通过性能测试发现:水泥稳定再生集料具有较好的强度,抗冻性能,水稳定性能;和水稳天然集料的抗压回弹模量相当;抗收缩变形性能较差.控制再生细集料掺加量可以非常好的满足半刚性基层材料的要求.

  13. Concrete evidence

    Energy Technology Data Exchange (ETDEWEB)

    Provis, J.; Duxson, P.; van Deventer, J. [University of Melbourne, Vic. (Australia)

    2008-11-15

    The time is right for a revolution in the cement industry which is responsible for 5-8% of all human-derived carbon dioxide emissions. Zeobond, an Australian company, has developed E-Crete which is a geopolymer concrete using fly ash and blast furnace slags which reduces CO{sub 2} emissions by 80% from the 0.67t of CO{sub 2} per ton of cement emitted by the Australian triple blend of cement, fly ash and slag. The article discusses the products development, standards for cements and challenges to the commercialization of E-Crete. 5 refs., 3 figs.

  14. Application of smart BFRP bars with distributed fiber optic sensors into concrete structures

    Science.gov (United States)

    Tang, Yongsheng; Wu, Zhishen; Yang, Caiqian; Wu, Gang; Zhao, Lihua; Song, Shiwei

    2010-04-01

    In this paper, the self-sensing and mechanical properties of concrete structures strengthened with a novel type of smart basalt fiber reinforced polymer (BFRP) bars were experimentally studied, wherein the sensing element is Brillouin scattering-based distributed optical fiber sensing technique. First, one of the smart bars was applied to strengthen a 2m concrete beam under a 4-points static loading manner in the laboratory. During the experiment, the bar can measure the inner strain changes and monitor the randomly distributed cracks well. With the distributed strain information along the bar, the distributed deformation of the beam can be calculated, and the structural health can be monitored and evaluated as well. Then, two smart bars with a length of about 70m were embedded into a concrete airfield pavement reinforced by long BFRP bars. In the field test, all the optical fiber sensors in the smart bars survived the whole concrete casting process and worked well. From the measured data, the concrete cracks along the pavement length can be easily monitored. The experimental results also confirmed that the bars can strengthen the structures especially after the yielding of steel bars. All the results confirm that this new type of smart BFRP bars show not only good sensing performance but also mechanical performance in the concrete structures.

  15. Concrete construction engineering handbook

    CERN Document Server

    Nawy, Edward G

    2008-01-01

    Provides coverage of concrete construction engineering and technology. This work features discussions focusing on: the advances in engineered concrete materials; reinforced concrete construction; specialized construction techniques; and, design recommendations for high performance.

  16. Potential applicability of stress wave velocity method on pavement base materials as a non-destructive testing technique

    Science.gov (United States)

    Mahedi, Masrur

    Aggregates derived from natural sources have been used traditionally as the pavement base materials. But in recent times, the extraction of these natural aggregates has become more labor intensive and costly due to resource depletion and environmental concerns. Thus, the uses of recycled aggregates as the supplementary of natural aggregates are increasing considerably in pavement construction. Use of recycled aggregates such as recycled crushed concrete (RCA) and recycled asphalt pavement (RAP) reduces the rate of natural resource depletion, construction debris and cost. Although recycled aggregates could be used as a viable alternative of conventional base materials, strength characteristics and product variability limit their utility to a great extent. Hence, their applicability is needed to be evaluated extensively based on strength, stiffness and cost factors. But for extensive evaluation, traditionally practiced test methods are proven to be unreasonable in terms of time, cost, reliability and applicability. On the other hand, rapid non-destructive methods have the potential to be less time consuming and inexpensive along with the low variability of test results; therefore improving the reliability of estimated performance of the pavement. In this research work, the experimental program was designed to assess the potential application of stress wave velocity method as a non-destructive test in evaluating recycled base materials. Different combinations of cement treated recycled concrete aggregate (RAP) and recycled crushed concrete (RCA) were used to evaluate the applicability of stress wave velocity method. It was found that, stress wave velocity method is excellent in characterizing the strength and stiffness properties of cement treated base materials. Statistical models, based on P-wave velocity were derived for predicting the modulus of elasticity and compressive strength of different combinations of cement treated RAP, Grade-1 and Grade-2 materials. Two

  17. Automated management for pavement inspection system (AMPIS)

    Science.gov (United States)

    Chung, Hung Chi; Girardello, Roberto; Soeller, Tony; Shinozuka, Masanobu

    2003-08-01

    An automated in-situ road surface distress surveying and management system, AMPIS, has been developed on the basis of video images within the framework of GIS software. Video image processing techniques are introduced to acquire, process and analyze the road surface images obtained from a moving vehicle. ArcGIS platform is used to integrate the routines of image processing and spatial analysis in handling the full-scale metropolitan highway surface distress detection and data fusion/management. This makes it possible to present user-friendly interfaces in GIS and to provide efficient visualizations of surveyed results not only for the use of transportation engineers to manage road surveying documentations, data acquisition, analysis and management, but also for financial officials to plan maintenance and repair programs and further evaluate the socio-economic impacts of highway degradation and deterioration. A review performed in this study on fundamental principle of Pavement Management System (PMS) and its implementation indicates that the proposed approach of using GIS concept and its tools for PMS application will reshape PMS into a new information technology-based system providing a convenient and efficient pavement inspection and management.

  18. FORECASTING OF ESTIMATED PERFORMANCE OF CONCRETE WITH ORGANIC AND HYDRAULIC BINDING AGENTS WITHIN WIDE RANGE OF TEMPERATURE AND STRAIN RATE

    Directory of Open Access Journals (Sweden)

    V. A. Verenko

    2010-01-01

    Full Text Available A methodology  for determination of estimated performance of main road-building materials (asphalt concrete and сold recycled material within wide range of temperature and strain rate, is developed in the paper and it allows to obtain the whole spectrum of parameters required for calculation of a road pavement structure with minimum number of test results. This technique can be useful in designing material and pavement structure during its repair while using the method of cold in-place recycling because it enables significantly to reduce a number of laboratory tests. The methodology has been implemented as a computer program for its practical application.

  19. Study on Asphalt Pavement Fatigue-Damage with Forecasting Axial Load Spectrum%按预测轴载谱分析沥青路面的疲劳损伤

    Institute of Scientific and Technical Information of China (English)

    马林; 葛折圣; 胡晓倩; 黄明波

    2011-01-01

    现行《公路沥青路面设计规范》(JTGG D50-2006)轴载等效换算方法难以反映超载、重载交通对路面结构的影响.结构层参数取值未考虑结构层在疲劳过程中的材料损伤,是重载交通沥青路面出现早期破坏的原因之一.采用预测轴载谱和Miner法则,计算分析了路面结构的疲劳损伤累积过程,并考虑不同使用阶段路面基层模量衰减对路面结构损伤进程的影响.结果表明,半刚性基层厚沥青面层路面结构的疲劳损伤累积进程明显优于目前国内较典型的半刚性基层沥青路面结构.研究结果为重载交通沥青路面结构设计指明了方向.%In Specifications for Design of Highway Asphalt Pavement (JTG D50-2006), the method of Equivalent Axle Loads could not reflect the influence on pavement structure by overload and heavy-load transportation. And the parameter of structural layers was no considering the material damage in the process of fatigue. It is one of the reasons why asphalt pavement is damaged early. The fatigue-damage accumulation in pavement structure was analyzed by using the forecasting axle load spectrum and Miner law. And the parameter of structural layers attenuated while the material damage in the process of fatigue. The results show that the fatigue damage accumulation process of semi-rigid base total thickness asphalt pavement structure is significantly better than the current domestic typical semi-rigid bituminous pavement structure. So this research results can help the development of structure design of heave-load asphalt pavement.

  20. Development of Improved Mechanistic Deterioration Models for Flexible Pavements

    DEFF Research Database (Denmark)

    Ullidtz, Per; Ertman, Hans Larsen

    1998-01-01

    The paper describes a pilot study in Denmark with the main objective of developing improved mechanistic deterioration models for flexible pavements based on an accelerated full scale test on an instrumented pavement in the Danish Road Tessting Machine. The study was the first in "International...... Pavement Subgrade Performance Study" sponsored by the Federal Highway Administration (FHWA), USA. The paper describes in detail the data analysis and the resulting models for rutting, roughness, and a model for the plastic strain in the subgrade.The reader will get an understanding of the work needed...