WorldWideScience

Sample records for source category asphalt

  1. 40 CFR 98.410 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Industrial Greenhouse Gases § 98.410 Definition of the source category. (a) The industrial gas supplier source category consists of any facility that...

  2. 40 CFR 98.110 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Ferroalloy Production § 98.110 Definition of the source category. The ferroalloy production source category consists of any facility that uses pyrometallurgical techniques to produce any of the following metals: ferrochromium, ferromanganese, ferromolybdenum...

  3. 6 Source Categories - Boilers (Proposed Action)

    Science.gov (United States)

    EPA is proposing options to simplify the Clean Air Act permitting process for certain smaller sources of air pollution commonly found in Indian country. This action would ensure that air quality in Indian country is protected.

  4. 40 CFR 98.360 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... this rule. (b) A manure management system (MMS) is a system that stabilizes and/or stores livestock... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Manure Management § 98.360 Definition of the source category. (a) This source category consists of livestock facilities with manure management systems that emit 25...

  5. 40 CFR 98.70 - Definition of source category.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Definition of source category. 98.70... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Ammonia Manufacturing § 98.70 Definition of source category...-based feedstock produced via steam reforming of a hydrocarbon. (b) Ammonia manufacturing processes in...

  6. 40 CFR 98.40 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Definition of the source category. 98... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electricity Generation § 98.40 Definition of the source... category does not include portable equipment, emergency equipment, or emergency generators, as defined in...

  7. 40 CFR 98.250 - Definition of source category.

    Science.gov (United States)

    2010-07-01

    ...; asphalt blowing operations; blowdown systems; storage tanks; process equipment components (compressors... plants (i.e., hydrogen plants that are owned or under the direct control of the refinery owner and...

  8. 40 CFR 98.420 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Definition of the source category. 98.420 Section 98.420 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... distribution of CO2. (4) Purification, compression, or processing of CO2. (5) On-site use of CO2 captured on...

  9. Task-Modulated Cortical Representations of Natural Sound Source Categories

    DEFF Research Database (Denmark)

    Hjortkjær, Jens; Kassuba, Tanja; Madsen, Kristoffer Hougaard

    2018-01-01

    In everyday sound environments, we recognize sound sources and events by attending to relevant aspects of an acoustic input. Evidence about the cortical mechanisms involved in extracting relevant category information from natural sounds is, however, limited to speech. Here, we used functional MRI...

  10. 40 CFR 98.240 - Definition of the source category.

    Science.gov (United States)

    2010-07-01

    ... makes methanol, hydrogen, and/or ammonia from synthesis gas is part of the petrochemical source category... hydrogen recovered as product and ammonia. The facility is part of subpart P of this part (Hydrogen... levels of both methanol and ammonia. The facility is part of subpart G of this part (Ammonia...

  11. 76 FR 4155 - National Emission Standards for Hazardous Air Pollutants for Source Categories: Gasoline...

    Science.gov (United States)

    2011-01-24

    ... 63 National Emission Standards for Hazardous Air Pollutants for Source Categories: Gasoline Distribution Bulk Terminals, Bulk Plants, and Pipeline Facilities; and Gasoline Dispensing Facilities; Final...] RIN 2060-AP16 National Emission Standards for Hazardous Air Pollutants for Source Categories: Gasoline...

  12. Acoustic Properties of Absorbent Asphalts

    Science.gov (United States)

    Trematerra, Amelia; Lombardi, Ilaria

    2017-08-01

    Road traffic is one of the greater cause of noise pollution in urban centers; a prolonged exposure to this source of noise disturbs populations subjected to it. In this paper is reported a study on the absorbent coefficients of asphalt. The acoustic measurements are carried out with a impedance tube (tube of Kundt). The sample are measured in three conditions: with dry material (traditional), “wet” asphalt and “dirty” asphalt.

  13. Preliminary data summary for the hospitals point-source category

    International Nuclear Information System (INIS)

    Strassler, E.; Hund, F.H.

    1989-09-01

    The summaries were prepared in order to allow EPA to respond to the mandate of Section 304(m) of the Clean Water Act. Summaries for categories already subject to rulemaking were developed for comparison purposes, and contain only the minimum amount of data needed to provide some perspective on the relative magnitude of the pollution problems created across the categories. The document summarizes the most current information available regarding the discharge of wastewater and solid wastes containing priority and hazardous non-priority pollutants by hospitals. The document provides a technical basis for determining whether additional national regulations should be developed pursuant to the Clean Water Act (CWA), and makes available preliminary information regarding the discharge of priority and hazardous non-priority pollutants by the hospital industry

  14. Tactics at the category level of purchasing and supply management: sourcing levers, contingencies and performance

    OpenAIRE

    Hesping, Frank

    2015-01-01

    For the ‘front-line’ purchasing agent, it is obvious that not all categories of products and supplier relationships should be managed in the same way. Rather, in a modern category management approach, firms group similar products into ‘sourcing categories’ forming coherent supply markets (e.g., ‘metal sheets’, ‘leather’, ‘displays’, ‘cables’, etc.). Thus, to achieve cost reduction targets, a tailored mix of tactical sourcing levers for each sourcing category may be required. The fundamental q...

  15. The Role of External Sources of Information in Children's Evaluative Food Categories

    Science.gov (United States)

    Nguyen, Simone P.

    2012-01-01

    Evaluative food categories are value-laden assessments, which reflect the healthfulness and palatability of foods (e.g. healthy/unhealthy, yummy/yucky). In a series of three studies, this research examines how 3- to 4-year-old children (N?=?147) form evaluative food categories based on input from external sources of information. The results…

  16. Tactics at the category level of purchasing and supply management: sourcing levers, contingencies and performance

    NARCIS (Netherlands)

    Hesping, Frank

    2015-01-01

    For the ‘front-line’ purchasing agent, it is obvious that not all categories of products and supplier relationships should be managed in the same way. Rather, in a modern category management approach, firms group similar products into ‘sourcing categories’ forming coherent supply markets (e.g.,

  17. Introductory asphalt technology; Nyumon asphalt gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Muroga, G. [Mitsubishi Oil Co. Ltd., Tokyo (Japan)

    1994-12-28

    The type and applications, manufacturing method, characteristics, road pavement etc. of asphalt were introduced. Among the petroleum asphalts, straight asphalt is used for road pavement,industry, and combustion, while blown asphalt is mainly used for the waterproofness of a building. Also, the demand for modified asphalt where rubber or thermoplastic elastomer was mixed is increasing. Straight asphalt is obtained by allowing atmospheric distillation tower bottom oil to be subjected to reduced pressure distillation and drawing reduced pressure gas oil and lubrication oil cut. Blown asphalt is produced by the oxidation dehydrogeneration and condensation polymerization reaction of soft straight asphalt. Rheology characteristics of asphalt are expressed by stiffness, relaxation elastic modulus, complex elastic modulus, etc. Also, asphalt has high electrical dielectric properties. Asphalt pavement has functions for dispersing traffic load and then transferring it to a lower layer, for resisting wear and cracking, and for preventing penetration of rainwater. 30 refs., 5 figs., 4 tabs.

  18. 77 FR 11390 - Delegation of National Emission Standards for Hazardous Air Pollutants for Source Categories; Nevada

    Science.gov (United States)

    2012-02-27

    ... Source Categories. Subpart ZZZZZZ--NESHAP: Area Source Standards for Aluminum, Copper, and Other... Perchloroethylene Dry X X X Cleaning. N Hard and Decorative X X X Chromium Electroplating and Chromium Anodizing... Publishing X X X Industry. LL Primary Aluminum Reduction X X Plants. MM Chemical Recovery X X Combustion...

  19. Asphalt cement poisoning

    Science.gov (United States)

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

  20. 40 CFR Table 1 to Subpart Xxxxxx... - Description of Source Categories Affected by This Subpart

    Science.gov (United States)

    2010-07-01

    ... heating units, combination gas-oil burners, oil or gas swimming pool heaters, heating apparatus (except... supplies industry sector of this source category includes establishments primarily engaged in high energy...), coke and gas burning salamanders, liquid or gas solar energy collectors, solar heaters, space heaters...

  1. Current status of securing Category 1 and 2 radioactive sources in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Y-F.; Tsai, C-H. [Atomic Energy Council of Executive Yuan of Taiwan (China)

    2014-07-01

    For enhancing safe and secure management of Category 1 and 2 radioactive sources against theft or unauthorized removal, AEC (Atomic Energy Council) of Taiwan have been regulating the import/export of the sources ever since 2005, in compliance with the IAEA's (International Atomic Energy Agency) 'Guidance on the Import and Export of Radioactive Sources'. Furthermore in consulting the IAEA Nuclear Security Series No.11 report, administrative regulations on the program of securing the sources have been embodied into AECL's regulatory system since 2012, for the purpose of enforcing medical and non-medical licensees and industrial radiographers to establish their own radioactive source security programs. Regulations require that security functions such as access control, detection, delay, response and communication and security management measures are to be implemented within the programs. This paper is to introduce the current status in implementing the security control measures in Taiwan. (author)

  2. Safety issues in the handling of radiation sources in category IV gamma radiation facilities

    International Nuclear Information System (INIS)

    Kohli, A.K.

    2002-01-01

    There is potential for incidents/accidents related to handling of radiation sources. This is increasing due to the fact that more number of plants that too with much larger levels of activity are now coming up. Such facilities produce very high levels of exposure rates during irradiation. A person accidentally present in the irradiation cell can receive a lethal dose within a very short time. Apart from safety requirements during operation and maintenance of these facilities, safety during loading and unloading of sources is important. Category IV type irradiators are the most common. Doubly encapsulated Co-60 slugs are employed to form the source pencils. These irradiators employ a water pool for safely storing the source pencils when irradiation of the products is not going on or when human access is needed into the irradiation cell for some maintenance or source loading/unloading operations. Safety during loading/unloading operations of source pencils is important. In design itself care needs to be taken such that all such operations are convenient and any incident will not lead to a situation where it becomes difficult to come out. Different situations, which can arise during handling of radiation sources and suggested designs to obviate such tight situations, are discussed. (Author)

  3. Anthropogenic Sulfur Dioxide Emissions, 1850-2005: National and Regional Data Set by Source Category, Version 2.86

    Data.gov (United States)

    National Aeronautics and Space Administration — The Anthropogenic Sulfur Dioxide Emissions, 1850-2005: National and Regional Data Set by Source Category, Version 2.86 provides annual estimates of anthropogenic...

  4. Modified asphalt; Kairyo asphalt ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Takarabe, A. [Mitsubishi Oil Co. Ltd., Tokyo (Japan)

    1994-12-28

    Modified asphalt in the area of road pavement in the relation of measures against flow on a road surface was introduced. The condition of road damage includes the print of a wheel, crack, and wear and semi-blown asphalt whose deformation is difficult even if temperature is increased to approximately 60 {degree}C and asphalt with rubber and resin are used to prevent these. The semi-blown asphalt is obtained by adding cut-back material to the normal asphalt, heating it, blowing air into it, and then oxidizing and polymerizing it, is harder and is more elastic than the normal asphalt, and has smaller viscosity change due to temperature change. The viscosity at 60 {degree}C was determined to be 10000{plus_minus}2000 poise according to the relationship between viscosity and crack using a large-scale execution experiment. The asphalt with rubber and resin is formed by adding modified material of styrene - butadiene copolymer and by adding thermoplastic elastomer and the former is used for preventing slide and the latter is used for preventing flow and wear. 10 refs., 6 figs., 2 tabs.

  5. Asphalt emulsion; Asphalt nyuzai ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, T. [Toa Doro Kogyo Co. Ltd., Tokyo (Japan)

    1994-12-28

    The emulsification, manufacture, type, applications, etc. of asphalt emulsion were introduced. The emulsification of asphalt is obtained by mixing heated asphalt into an emulsification liquid where emulsifier is added to water and then agitating it. The emulsifier has both hydrophilic and lipophilic parts in the same molecule, prevents collision between asphalt particles after being arranged properly on the surface of asphalt particles, and prevent separation into water and asphalt. The emulsion is available for penetration and for mixing depending on applications and can be classified into cation emulsion, anion emulsion, and nonionic emulsion according to the property. The emulsion is mainly applied to road pavement, reaching approximately 90 % of the total manufactured emulsion. It is also used for other areas such as the filler of a slab race of each bullet train of Sanyo, Tohoku, and Jyoetsu and is also applied to the formation of a water-proof layer by spraying a high-concentration emulsion with rubber, agricultural water channels using asphalt emulsion and nonwoven cloth, etc. in civil engineering and agricultural fields. 2 refs., 13 figs., 8 tabs.

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

    Directory of Open Access Journals (Sweden)

    Mohammad Saeed Pourtahmasb

    2014-01-01

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

  7. Anaerobic biodegradability of Category 2 animal by-products: methane potential and inoculum source.

    Science.gov (United States)

    Pozdniakova, Tatiana A; Costa, José C; Santos, Ricardo J; Alves, M M; Boaventura, Rui A R

    2012-11-01

    Category 2 animal by-products that need to be sterilized with steam pressure according Regulation (EC) 1774/2002 are studied. In this work, 2 sets of experiments were performed in mesophilic conditions: (i) biomethane potential determination testing 0.5%, 2.0% and 5.0% total solids (TS), using sludge from the anaerobic digester of a wastewater treatment plant as inoculum; (ii) biodegradability tests at a constant TS concentration of 2.0% and different inoculum sources (digested sludge from a wastewater treatment plant; granular sludge from an upflow anaerobic sludge blanket reactor; leachate from a municipal solid waste landfill; and sludge from the slaughterhouse wastewater treatment anaerobic lagoon) to select the more adapted inoculum to the substrate in study. The higher specific methane production was of 317 mL CH(4)g(-1) VS(substrate) for 2.0% TS. The digested sludge from the wastewater treatment plant led to the lowest lag-phase period and higher methane potential rate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Journey of a Package: Category 1 Source (Co-60) Shipment with Several Border Crossings, Multiple Modes

    International Nuclear Information System (INIS)

    Gray, P. A.

    2016-01-01

    Radioactive materials (RAM) are used extensively in a vast array of industries and in an even wider breadth of applications on a truly global basis each and every day. Over the past 50 years, these applications and the quantity (activity) of RAM shipped has grown significantly, with the next 50 years expected to show a continuing trend. The movement of these goods occurs in all regions of the world, and must therefore be conducted in a manner which will not adversely impact people or the environment. Industry and regulators have jointly met this challenge, so much so that RAM shipments are amongst the safest of any product. How has this level of performance been achieved? What is involved in shipping RAM from one corner of the world to another, often via a number of in-transit locations and often utilizing multiple modes of transport in any single shipment? This paper reviews one such journey, of Category 1 Cobalt-60 sources, as they move from point of manufacture through to point of use including the detailed and multi-approval process, the stringent regulatory requirements in place, the extensive communications required throughout, and the practical aspects needed to simply offer such a product for sale and transport. Upon completion, the rationale for such an exemplary safety and security record will be readily apparent. (author)

  9. Spectral and temporal cues for perception of material and action categories in impacted sound sources

    DEFF Research Database (Denmark)

    Hjortkjær, Jens; McAdams, Stephen

    2016-01-01

    In two experiments, similarity ratings and categorization performance with recorded impact sounds representing three material categories (wood, metal, glass) being manipulated by three different categories of action (drop, strike, rattle) were examined. Previous research focusing on single impact...... correlated with the pattern of confusion in categorization judgments. Listeners tended to confuse materials with similar spectral centroids, and actions with similar temporal centroids and onset densities. To confirm the influence of these different features, spectral cues were removed by applying...

  10. 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…

  11. Bladder cancer incidence and exposure to polycyclic aromatic hydrocarbons among asphalt pavers.

    Science.gov (United States)

    Burstyn, Igor; Kromhout, Hans; Johansen, Christoffer; Langard, Sverre; Kauppinen, Timo; Shaham, Judith; Ferro, Gilles; Boffetta, Paolo

    2007-08-01

    To investigate the association between exposures to polycyclic aromatic hydrocarbons (PAH) that arises during asphalt paving, and risk of bladder cancer. 7298 men included in the historical cohort were first employed between 1913 and 1999 in companies applying asphalt in Denmark, Norway, Finland and Israel. The minimal duration of employment for inclusion in the cohort was two seasons of work. Occupational histories were extracted from personnel files. A follow-up for cancer incidence was conducted through national cancer registries. The authors estimated exposures to benzo(a)pyrene as a marker for 4-6 ring PAH. Exposures were reconstructed by using information about changes in asphalt paving technology in each company over time, the modelled relation between production characteristics and exposure levels, and job histories. Relative risks and associated 95% confidence intervals were estimated using Poisson regression. 48 bladder cancers among asphalt paving workers were detected; of these, 39 cases were exposed at least 15 years before the diagnosis. Cumulative exposure to PAH was not associated with the incidence of bladder cancer. The association with average exposure became stronger when 15-year lag was considered, revealing a twofold increase in relative bladder cancer risk in the two higher exposure categories. There was an indication of exposure-response association with lagged averaged exposure. Risk estimates were adjusted for age, country, duration of employment and calendar period, did not show heterogeneity among countries and did not materially change when re-estimated after excluding non-primary cancers from follow-up. Previously conducted sensitivity analysis indicates that confounding by cigarette smoking is an unlikely explanation for the observed exposure-response trends. The authors were unable to control for all possible sources of confounding and bias. The results do not allow conclusion on the presence or absence of a causal link between

  12. Recycling of Reclaimed Asphalt Pavement in Portland Cement Concrete

    Directory of Open Access Journals (Sweden)

    Salim Al-Oraimi

    2009-06-01

    Full Text Available Reclaimed Asphalt Pavement (RAP is the result of removing old asphalt pavement material. RAP consists of high quality well-graded aggregate coated with asphalt cement. The removal of asphalt concrete is done for reconstruction purposes, resurfacing, or to obtain access to buried utilities. The disposal of RAP represents a large loss of valuable source of high quality aggregate. This research investigates the properties of concrete utilizing recycled reclaimed asphalt pavement (RAP. Two control mixes with normal aggregate were designed with water cement ratios of 0.45 and 0.5. The control mixes resulted in compressive strengths of 50 and 33 MPa after 28 days of curing. The coarse fraction of RAP was used to replace the coarse aggregate with 25, 50, 75, and 100% for both mixtures. In addition to the control mix (0%, the mixes containing RAP were evaluated for slump, compressive strength, flexural strength, and modulus of elasticity. Durability was evaluated using surface absorption test.

  13. Asphalt chemical fractionation

    International Nuclear Information System (INIS)

    Obando P, Klever N.

    1998-01-01

    Asphalt fractionation were carried out in the Esmeraldas Oil Refinery using n-pentane, SiO 2 and different mixture of benzene- methane. The fractions obtained were analyzed by Fourier's Transformed Infrared Spectrophotometry (FTIR)

  14. Effects of conductive fillers on temperature distribution of asphalt pavements

    International Nuclear Information System (INIS)

    Chen Mingyu; Wu Shaopeng; Zhang Yuan; Wang Hong

    2010-01-01

    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.

  15. Impact of Modificated Asphalt Mixtures on Paving Functioning and Environment

    Directory of Open Access Journals (Sweden)

    Gediminas Gribulis

    2016-10-01

    Full Text Available Atmospheric pollution began to increase in the beginning of 19th century, when the global economy and industrial development started the signal grow. The current problem of global warming is partly related with emission of carbon dioxide (CO2 to environment, which one of the sources are industrial production companies. Warm asphalt mix is usually used in the practice of Lithuania and the world for equipment of road paving. These mixes are produced in specialized asphalt mixers where stone dosing, drying and its mixing with bituminous binders are performed. The temperature of produced hot asphalt mix in mixer reach 150–180 °C and 120–160 °C of mixture laying on the road. Various pollutants, carbon dioxide, formaldehydes, and other are spread to the environment. The carried out researches in Lithuania and the world have showed that while using special additives it is possible to reduce the temperatures of warm asphalt production and laying on the road. Such reduction of temperature helps not to worsen the quality of asphalt layer, to lower the emission of pollutants to environment, to improve the conditions of road workers and to economically use the gas for production of asphalt mixes. Production technologies of different asphalt mixes, their advantages and disadvantages, and results of laboratory tests are analyzed in this article. Equipment samples of experimental road sections, using the warm mixing asphalt mixtures are given.

  16. A source mixing model to apportion PAHs from coal tar and asphalt binders in street pavements and urban aquatic sediments

    Energy Technology Data Exchange (ETDEWEB)

    Ahrens, M.J.; Depree, C.V. [National Institute of Water & Atmospheric Research, Hamilton (New Zealand)

    2010-12-15

    Present-day and more than 30 years old road and footpath pavements from Auckland, New Zealand were analysed for PAHs to test the hypothesis that coal tar based pavement binders contribute to unusually high PAH concentrations in adjacent stream and estuarine sediments Total PAH ({Sigma}{sub 28}PAH) concentrations in the dichloromethane-soluble fraction ('binder'), comprising 5-10% of pavement mass, were as high as 200 000 mg kg{sup -1}(10 000 mg kg{sup -1} in binder + aggregate) Older and deeper pavement layers were strongly pyrogenic, whereas pavement layers from recently sealed roads had a more petrogenic composition and more than 1000 times lower Sigma(28)PAH concentrations. Source identification analysis using three PAH isomer ratio pairs (benz(a)anthracene/(benz(a)anthracene + chrysene), benzo(a)pyrene/(benzo(a)pyrene + benzo(e)pyrene)), and indeno(1,2,3-cd)pyrene/(indeno(1,2,3-cd)pyrene + benzo(g,h,i)perylene) revealed low PAH (bitumen) pavements to have consistently lower isomer ratios than high PAH (coal tar) samples. A concentration-weighted mixing model, with coal tar and bitumen as source materials, explained more than 80% of the variance in isomer ratios and enveloped the entire PAH compositional and concentration range encountered PAH composition and concentrations in adjacent stream sediments ({gt} 15 mg kg{sup -1} dry weight) were consistent with diluted coal tar material as a principal PAH source. Due to the very high PAH concentrations of coal tar, a coal tar content of as little as 0.01% of total sediment mass can account for more than 90% of PAH concentrations in adjacent stream sediments.

  17. Numerical simulation on the thermal response of heat-conducting asphalt pavements

    Energy Technology Data Exchange (ETDEWEB)

    Wang Hong; Wu Shaopeng; Chen Mingyu; Zhang Yuan, E-mail: wusp@whut.edu.c [Key Laboratory of Silicate Materials Science and Engineering, Ministry of Education, Wuhan University of Technology, Wuhan 430070 (China)

    2010-05-01

    Using asphalt pavements as a solar collector is a subject of current interest all over the world because the sun provides a cheap and abundant source of clean and renewable energy, which can be captured by black asphalt pavements. A heat-conducting device is designed to absorb energy from the sun. In order to validate what parameters are critical in the asphalt collector, a finite element model is developed to predict the thermal response of the heat-conducting device compared to the conventional asphalt mixture. Some factors that may affect the asphalt pavement collector are considered, including the coefficient of heat conductivity of the asphalt pavement, the distance between pipes with the medium, water, and the pipe's diameter. Ultimately, the finite element model can provide pavement engineers with an efficient computational tool that can be a guide to the conductive asphalt solar collector's experiment in the laboratory.

  18. Numerical simulation on the thermal response of heat-conducting asphalt pavements

    International Nuclear Information System (INIS)

    Wang Hong; Wu Shaopeng; Chen Mingyu; Zhang Yuan

    2010-01-01

    Using asphalt pavements as a solar collector is a subject of current interest all over the world because the sun provides a cheap and abundant source of clean and renewable energy, which can be captured by black asphalt pavements. A heat-conducting device is designed to absorb energy from the sun. In order to validate what parameters are critical in the asphalt collector, a finite element model is developed to predict the thermal response of the heat-conducting device compared to the conventional asphalt mixture. Some factors that may affect the asphalt pavement collector are considered, including the coefficient of heat conductivity of the asphalt pavement, the distance between pipes with the medium, water, and the pipe's diameter. Ultimately, the finite element model can provide pavement engineers with an efficient computational tool that can be a guide to the conductive asphalt solar collector's experiment in the laboratory.

  19. Warm mix asphalt : final report.

    Science.gov (United States)

    2014-11-01

    The performance of pavements constructed using warm mix asphalt (WMA) technology were : compared to the performance of conventional hot mix asphalt (HMA) pavements placed on the : same project. Measurements of friction resistance, rutting/wear, ride ...

  20. Methodologies for estimating air emissions from three non-traditional source categories: Oil spills, petroleum vessel loading and unloading, and cooling towers. Final report, October 1991-March 1993

    International Nuclear Information System (INIS)

    Ramadan, W.; Sleva, S.; Dufner, K.; Snow, S.; Kersteter, S.L.

    1993-04-01

    The report discusses part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to develop appropriate emissions estimation methodologies and emission factors for a group of these source categories. Based on the results of the identification and characterization portions of this research, three source categories were selected for methodology and emission factor development: oil spills, petroleum vessel loading and unloading, and cooling towers. The report describes the category selection process and presents emissions estimation methodologies and emission factor data for the selected source categories. The discussions for each category include general background information, emissions generation activities, pollutants emitted, sources of activity and pollutant data, emissions estimation methodologies and data issues. The information used in these discussions was derived from various sources including available literature, industrial and trade association publications and contracts, experts on the category and activity, and knowledgeable federal and state personnel

  1. Dismantling of asphalt and recycling road materials in asphalt layers

    OpenAIRE

    Antunes, M. L.; Batista, F. A.

    2009-01-01

    Este registo pertence ao Repositório Científico do LNEC The interest of recycling of asphalt and other road materials for pavement construction and rehabilitation has been generally growing in Portugal, for the last 15 years. After some occasional demonstration projects dealing with hot and cold in situ recycling of asphalt layers, the first significant experiences with cold in situ recycling and hot mix plant recycling of asphalt applied in full scale rehabilitation projects, ...

  2. A review of asphalt and asphalt mixture aging

    Directory of Open Access Journals (Sweden)

    Wilmar Darío Fernández-Gómez

    2013-01-01

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

  3. Performance prediction of hot mix asphalt from asphalt binders

    International Nuclear Information System (INIS)

    Hafeez, I.; Kamal, M.A.; Shahzad, Q.; Bashir, N.; Ahadi, M.R.

    2012-01-01

    Asphalt binder being a high weight hydrocarbon contains asphaltene and maltene and is widely used as cementing materials in the construction of flexible pavements. Its performance in hot mix asphalt also depends on combining with different proportions of aggregates. The main objective of this study was to characterize asphalt cement rheological behavior and to investigate the influence of asphalt on asphalt-aggregate mixtures prepared with virgin binders and using polymers. Binder rheology and mixtures stiffness were determined under a range of cyclic loadings and temperature conditions. Master curves were developed for the evaluation of relationship between parameters like complex modulus and phase angle at different frequencies. Horizontal shift factors were also computed to determine time and temperature response of binders and mixes. The results showed that the stiffness of both the binder and the mixes depends on temperature and frequency of load. Polymer modified binder is least susceptible to temperature variations as compared to other virgin asphalt cement. Performance of asphalt mixtures can be predicted from those of asphalt binders using the master curve technique. (author)

  4. Evaluation of the performance of aggregate in hot-mix asphalt

    CSIR Research Space (South Africa)

    Komba, Julius J

    2014-07-01

    Full Text Available The overall performance of an asphalt mix is dependent on, amongst others, the properties of the constituent materials, which include aggregate, binder and filler. The aggregate for production of asphalt mixes is usually sourced from a quarry, which...

  5. Recovery of asphalt from bituminous minerals

    Energy Technology Data Exchange (ETDEWEB)

    Jossinet, J

    1881-12-31

    A process is disclosed for the recovery of asphalt from bituminous minerals, consisting in that the mineral is extracted with mineral oil, which is recovered by distilling the raw asphalt and distilling the solution to obtain on the one hand the liquid oil contained in the raw asphalt for use in the extraction and on the other hand distilled asphalt.

  6. Mechanical Properties of Warm Mix Asphalt Prepared Using Foamed Asphalt Binders : Executive Summary Report

    Science.gov (United States)

    2011-03-01

    Hot mix asphalt (HMA) is a mixture containing aggregates and asphalt binders prepared at specified : proportions. The aggregates and asphalt binder proportions are determined through a mix design : procedure such as the Marshall Mix Design or the Sup...

  7. Contested Categories

    DEFF Research Database (Denmark)

    Drawing on social science perspectives, Contested Categories presents a series of empirical studies that engage with the often shifting and day-to-day realities of life sciences categories. In doing so, it shows how such categories remain contested and dynamic, and that the boundaries they create...

  8. Alabama warm mix asphalt field study : final report.

    Science.gov (United States)

    2010-05-01

    The Alabama Department of Transportation hosted a warm mix asphalt field demonstration in August 2007. The warm mix asphalt technology demonstrated was Evotherm Dispersed Asphalt Technology. The WMA and hot mix asphalt produced for the demonstration ...

  9. Laboratory Measurements of Particulate Matter Concentrations from Asphalt Pavement Abrasion

    Directory of Open Access Journals (Sweden)

    Fullová Daša

    2016-12-01

    Full Text Available The issue of emissions from road traffic is compounded by the fact that the number of vehicles and driven kilometres increase each year. Road traffic is one of the main sources of particulate matter and traffic volume is still increasing and has unpleasant impact on longevity of the pavements and the environment. Vehicle motions cause mechanical wearing of the asphalt pavement surface - wearing course by vehicle tyres. The contribution deals with abrasion of bituminous wearing courses of pavements. The asphalt mixtures of wearing courses are compared in terms of mechanically separated particulate matter. The samples of asphalt mixtures were rutted in wheel tracking machine. The particulate matter measurements were performed in laboratory conditions. The experimental laboratory measurements make it possible to sample particulates without contamination from exhaust emissions, abraded particles from vehicles, resuspension of road dust and climate affects. The contribution offers partial results of measurements on six trial samples of asphalt mixtures with different composition. It presents particulate matter morphology and the comparison of rutted asphalt samples in terms of PM mass concentrations and chemical composition.

  10. Asphalt emulsion sealing of uranium mill tailings. 1979 annual report

    International Nuclear Information System (INIS)

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-06-01

    Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory: the use of asphalt emulsion to contain radon and other potentially hazardous materials in uranium tailings. Results of these studies indicate that radon flux from uranium tailings can be reduced by greater than 99% by covering the tailings with an asphalt emulsion that is poured on or sprayed on (3.0 to 7.0 mm thick), or mixed with some of the tailings and compacted to form an admixture seal (2.5 to 15.2 cm) containing 18 wt % residual asphalt

  11. Hydrogenizing oils, asphalts, etc

    Energy Technology Data Exchange (ETDEWEB)

    1925-03-14

    The hydrogenation of carbonaceous solids in presence of combined sulfur, e.g., sulfides as described in the parent specification is applied to the treatment of rock oils, shale oils, resins, ozokerite, asphalt, and the like, or fractions, residues, or acid sludge or other conversion products thereof, alone or mixed. Preferably the hydrogen or other reducing gas is in excess and under pressure, and is either circuited or led through a series of treatment vessels, hydrogen being added for that used. In an example, residues from American crude oil are passed continuously with hydrogen at 200 atmospheres and 450 to 500/sup 0/C over pressed precipitated cobalt sulfide, the issuing gases being cooled to condense the light oil produced.

  12. Investigation of Warm Mix Asphalt (WMA) Technologies and Increased Percentages of Reclaimed Asphalt Pavement (RAP) in Asphalt Mixtures

    Science.gov (United States)

    2011-04-01

    The implementation of warm-mix asphalt (WMA) is becoming more widespread with a growing number of contractors utilizing various WMA technologies. Early research suggests WMA may be more susceptible to moisture damage than traditional hot-mix asphalt ...

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

    Science.gov (United States)

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

    2016-03-01

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

  14. Arrangement for the measurement of the quantity of asphalt in an asphaltic compound

    International Nuclear Information System (INIS)

    Noma, I.; Taniguchi, K.

    1978-01-01

    The arrangement for the measurement of the quantity of asphalt in an asphaltic compound in an apparatus for the mixture of asphalt components and an aggregate for the formation of an asphaltic compound characterized by the inclusion of a member for the transmission of a neutron beam which reacts with the hydrogen atoms in the asphaltic compound in such a way that the energy of a neutron beam is adsorbed; a continuous transport device feeds a continuous supply of the asphalt compound past the neutron beam; a member responds to an automatic detector for the quantity of asphaltic components in the asphaltic compound and provides an adjustment so that the quantity [of asphaltic components in asphaltic compound] may be held at a constant value. (G.C.)

  15. Liver transplantation from maastricht category 2 non-heart-beating donors: a source to increase the donor pool?

    Science.gov (United States)

    Otero, A; Gómez-Gutiérrez, M; Suárez, F; Arnal, F; Fernández-García, A; Aguirrezabalaga, J; García-Buitrón, J; Alvarez, J; Máñez, R

    2004-04-01

    The demand for liver transplantation has increasingly exceeded the supply of cadaver donor organs. Non-heart-beating donors (NHBDs) may be an alternative to increase the cadaver donor pool. The outcome of 20 liver transplants from Maastricht category 2 NHBD was compared with that of 40 liver transplants from heart-beating donors (HBDs). After unsuccessful cardiopulmonary resuscitation (CPR), cardiopulmonary support with simultaneous application of chest and abdominal compression (CPS; n = 6) or cardiopulmonary bypass (CPB; n = 14) was used to maintain the donors. At a minimum follow-up of 2 years, actuarial patient and graft survival rates with livers from Maastricht category 2 NHBD were 80% and 55%, respectively. Transplantation of organs from these donors was associated with a significantly higher incidence of primary nonfunction, biliary complications, and more severe initial liver dysfunction compared with organs from HBDs. The graft survival rates was 83% for livers from NHBDs preserved with CPS and 42% in those maintained with CPB.

  16. A review of warm mix asphalt.

    Science.gov (United States)

    2008-12-01

    Warm Mix Asphalt (WMA) technology, recently developed in Europe, is gaining strong interest in the US. By : lowering the viscosity of asphalt binder and/or increasing the workability of mixture using minimal heat, WMA : technology allows the mixing, ...

  17. Controlling conductivity of asphalt concrete with graphite.

    Science.gov (United States)

    2014-08-01

    Electrically conductive asphalt concrete has a huge potential for various multifunctional applications such as : self-healing, self-sensing, and deicing. In order to utilize the full spectrum of applications of electrically conductive : asphalt compo...

  18. Constructing better roads with asphalt rubber

    Directory of Open Access Journals (Sweden)

    Pais Jorge C.

    2015-12-01

    Full Text Available Brazilians mixtures containing asphalt rubber were evaluated by mechanical laboratory tests. A conventional mixture with asphalt CAP-50/70 was produced as a mixture control. With the aim of compare the Brazilians mixtures performance, a Portuguese asphalt rubber mixture was tested as well. The testing set involved the determination of the mechanical properties, fatigue and permanent deformation, of asphalt rubber produced by wet process through two different systems: continuous blend and terminal blend. The asphalt rubber morphology was evaluated in order to determine the compatibility of the systems. The asphalt rubber mixtures exhibit good resistance to permanent deformation and prolonged fatigue life in relation to mixture control. Therefore it is concluded that the application of asphalt rubber alters the characteristics of asphalt mixture in a very beneficial way.

  19. VISCOELASTIC STRUCTURAL MODEL OF ASPHALT CONCRETE

    Directory of Open Access Journals (Sweden)

    V. Bogomolov

    2016-06-01

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

  20. The crack growth mechanism in asphaltic mixes

    NARCIS (Netherlands)

    Jacobs, M.M.J.; Hopman, P.C.; Molenaar, A.A.A.

    1995-01-01

    The crack growth mechanism in asphalt concrete (Ac) mixes is studied. In cyclic tests on several asphaltic mixes crack growth is measured, both with crack foils and with cOD-gauges. It is found that crack growth in asphaltic mixes is described by three processes which are parallel in time: cohesive

  1. Induction Healing of Porous Asphalt Concrete

    NARCIS (Netherlands)

    Liu, Q.

    2012-01-01

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

  2. Evaluation of recycled asphaltic concrete : final report.

    Science.gov (United States)

    1977-01-01

    This report describes a project in which approximately 6,200 tons (5,630 Mg) of asphaltic concrete were recycled through a conventional asphalt batch plant. During the construction of the project, a buildup of asphalt-coated fines occurred in the dry...

  3. Characterization of asphalt treated base course material

    Science.gov (United States)

    2010-06-01

    Asphalt-treated bases are often used in new pavements; the materials are available and low-cost, but there is little data on how these materials perform in cold regions. : This study investigated four ATB types (hot asphalt, emulsion, foamed asphalt,...

  4. Initiative assessment of asphalt works

    International Nuclear Information System (INIS)

    Rikheim, Bente; Kjerschow, Einar

    2003-01-01

    Several asphalt works are utilizing heat from combustion of used oil for drying and heating of rock material in the production of asphalt. According to new regulations on combustion of waste, used oil is to be regarded as waste and subject to emission requirements according to the combustion regulations. Measurements show that emissions of CO, dust, dioxins, TOC and SO 2 exceed the limits set by the regulations. To conform to the regulations these asphalt works must improve their combustion technique. However, such measures may lead to increased formation of NOx. It is recommended that a combustion chamber for drying of rock material should be used in order to reduce the emissions of CO and TOC concentrations. The concentration of SO 2 may be reduced by dry cleaning by means of injection of lime. In the same way, active carbon is injected to remove dioxins. The asphalt works must be outfitted with measuring equipment that monitors and records certain operation and control parameters and some emission to air parameters. Periodic measurements are to be done of heavy metals and dioxins. It is estimated that the measures necessary to make the asphalt works comply with the regulations will cost about NOK 4 530 000 in investment per plant and that the operation expenses will increase by NOK 700 000 per year per plant. This includes maintenance, control etc

  5. Waterproofing improvement of radioactive waste asphalt solid

    International Nuclear Information System (INIS)

    Adachi, Katsuhiko; Yamaguchi, Takashi; Ikeoka, Akira.

    1981-01-01

    Purpose: To improve the waterproofing of asphalt solid by adding an alkaline earth metal salt and, further, paraffin, into radioactive liquid waste when processing asphalt solidification of the radioactive liquid waste. Method: Before processing molten asphalt solidification of radioactive liquid waste, soluble salts of alkaline earth metal such as calcium chloride, magnesium chloride, or the like is added to the radioactive liquid waste. Paraffin having a melting point of higher than 60 0 C, for example, is added to the asphalt, and waterproofing can be remarkably improved. The waste asphalt solid thus fabricated can prevent the swelling thereof, and can improve its waterproofing. (Yoshihara, H.)

  6. Thermal behavior of asphalt cements

    International Nuclear Information System (INIS)

    Claudy, P.M.; Letoffe, J.M.; Martin, D.; Planche, J.P.

    1998-01-01

    Asphalt cements are highly complex mixtures of hydrocarbon molecules whose thermal behavior is of prime importance for petroleum and road industry. From DSC, the determination of several thermal properties of asphalts is given, e.g. glass-transition temperature and crystallized fraction content.The dissolution of a pure n-paraffin C n H 2n+2 in an asphalt, as seen by DSC, should be a single peak. For 20 g of these glasses change with time and temperature. The formation of the crystallized phases is superposed to the enthalpic relaxation of the glasses, making a kinetic study very difficult. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Analysis of the usage of rubberized asphalt in hot mix asphalt using Reclaimed Asphalt Pavement (RAP)

    Science.gov (United States)

    Dwidarma Nataadmadja, Adelia; Prahara, Eduardi; Sumbung, Pierre Christian

    2017-12-01

    There has been an increasing demand in using more environmentally friendly materials in pavement construction. One of the alternative materials that have been widely used is the Reclaimed Asphalt Pavement (RAP) aggregates. The RAP aggregates are derived from the crushed and screened pavement materials that contain asphalt and aggregates. This material is usually combined with natural aggregates and virgin asphalt binder to construct a new pavement. There have been numerous positive feedbacks in using this material although RAP aggregates also have certain weaknesses, such as questionable interaction between virgin and recycled materials and increased stiffness of RAP binder. Moreover, there has been a push on using rubber as an additive to asphalt binder to improve the welfare of rubber farmers. This research combines the usage of both latex and RAP as the ingredients to design hot mix asphalt (HMA) as latex could help in improving the flexibility of HMA and the interaction between the virgin and recycled materials. The main objective of this research is to find a suitable percentage of RAP aggregates to be used in HMA with certain percentage of latex as the binder additive.

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

    Directory of Open Access Journals (Sweden)

    Seong-Hyeok Lee

    2015-01-01

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

  9. Effects of Fiber Finish on the Performance of Asphalt Binders and Mastics

    Directory of Open Access Journals (Sweden)

    Bradley J. Putman

    2011-01-01

    Full Text Available The objective of this study was to determine the effects of finishes applied to polyester fibers on the properties of asphalt binders and mastics. Asphalt binders were mixed with finishes that were extracted from the fibers, and mastics were also made with binder and fibers (with and without finish to isolate the effects of the finish. The results indicated that crude source plays a significant role in how the fiber finish affects the binders and mastics. Additionally different finishes had different effects on binder properties. The major finding of this study is that different polyester fibers, even from the same manufacturer, may not necessarily perform the same in an asphalt mixture. It is important to use fibers that are compatible with the particular asphalt binder that is being used because of the significance of the binder source on the interaction between the finish and the binder.

  10. Quantifying the environmental burdens of the hot mix asphalt (HMA pavements and the production of warm mix asphalt (WMA

    Directory of Open Access Journals (Sweden)

    Mithil Mazumder

    2016-05-01

    Full Text Available Asphalt pavement has significant environmental burdens throughout its life cycle. A life cycle assessment (LCA model is used to quantify the environmental burdens for material, construction, maintenance and use phases of hot mix asphalt (HMA pavement. Two peer reviewed journals have been used to collect all of the inventory loadings as an input for the LCA model and ten impact categories have been evaluated as output. The result of the inventory analysis is a summary of all inflows and outflows related to the “functional unit”. The result of each impact category is the total of all the individually characterized inventory loadings in each category. Each life cycle phase of HMA pavement has been quantified on these ten impact categories and a comparison provided among the phases to understand the percentage contribution to the environment. Human and eco toxicity values are higher for the material phase, whereas the rest of the impact categories are significant in the use phase. The material phase contributes 97% of the overall human toxicity in water from standpoint of asphalt pavements, whereas in the material phase the production of bitumen is responsible for 90% human and eco toxicity in terms of air based burden. As a solution, the life cycle inventory of WMA has been estimated and reduction only done in HMA production. From analysis, it was estimated that WMA provides a reduction of 29% on the acidification impact and 25% reduction on both fossil fuel consumption and photo oxidant formation impact of HMA. Keywords: Life cycle analysis, Environmental burdens, Inventories, HMA, Impacts, WMA

  11. Effect of using of reclaimed asphalt and/or lower temperature asphalt on the availability of the road network

    NARCIS (Netherlands)

    Nicholls, C.; Wayman, M.; Mollenhauer, K.; McNally, C.; Tabakovic, A.; Varveri, A.; Cassidy, S.; Shahmohammadi, R.; Taylor, R.

    2015-01-01

    The use of reclaimed asphalt, secondary component materials and/or additives and lower temperature asphalt are being increasingly used in order to improve the sustainability of asphalt production. The use of reclaimed asphalt reduces the need for virgin materials whilst lower temperature asphalts

  12. Leaching of organic contaminants from storage of reclaimed asphalt pavement.

    Science.gov (United States)

    Norin, Malin; Strömvall, A M

    2004-03-01

    Recycling of asphalt has been promoted by rapid increases in both the use and price of petroleum-based bitumen. Semi-volatile organic compounds in leachates from reclaimed asphalt pavement, measured in field samples and in laboratory column test, were analysed through a GC/MS screen-test methodology. Sixteen PAH (polyaromatic hydrocarbons) were also analysed in leachates from the column study. The highest concentrations of semi-volatile compounds, approximately 400 microg l(-1), were measured in field samples from the scarified stockpile. Naphthalene, butylated hydroxytoluene (BHT) and dibutyl phthalate (DBP) were the most dominant of the identified semi-volatiles. The occurrence of these compounds in urban groundwater, also indicate high emission rates and persistent structures of the compounds, making them potentially hazardous. Car exhausts, rubber tires and the asphalt material itself are all probable emission sources, determined from the organic contaminants released from the stockpiles. The major leaching mechanism indicated was dissolution of organic contaminants from the surface of the asphalt gravels. In the laboratory column test, the release of high-molecular weight and more toxic PAH was higher in the leachates after two years than at the commencement of storage. The concentrations of semi-volatiles in leachates, were also several times lower than those from the field stockpile. These results demonstrate the need to follow up laboratory column test with real field measurements.

  13. Development document for the effluent limitations and guidelines for the ore mining and dressing point source category. Volume I. Final report

    International Nuclear Information System (INIS)

    Jarrett, B.M.; Kirby, R.G.

    1978-07-01

    To establish effluent limitation guidelines and standards of performance, the ore mining and dressing industry was divided into 41 separate categories and subcategories for which separate limitations were recommended. This report deals with the entire metal-ore mining and dressing industry and examines the industry by ten major categories: iron ore; copper ore; lead and zinc ores; gold ore; silver ore; bauxite ore; ferroalloy-metal ores; mercury ores; uranium, radium and vanadium ores; and metal ores, not elsewhere classified ((ores of antimony, beryllium, pltinum, rare earths, tin, titanium, and zirconium). The subcategorization of the ore categories is based primarily upon ore mineralogy and processing or extraction methods employed; however, other factors (such as size, climate or location, and method of mining) are used in some instances. With the best available technology economically achievable, facilities in 21 of the 41 subcategories can be operated with no discharge of process wastewater to navigable waters. No discharge of process wastewater is also achievable as a new source performance standard for facilities in 21 of the 41 subcategories

  14. Design and evaluation of foamed asphalt base materials.

    Science.gov (United States)

    2013-05-01

    Foamed asphalt stabilized base (FASB) combines reclaimed asphalt pavement (RAP), recycled : concrete (RC), and/or graded aggregate base (GAB) with a foamed asphalt binder to produce a : partially stabilized base material. The objectives of this study...

  15. Organizational Categories as Viewing Categories

    OpenAIRE

    Mik-Meyer, Nanna

    2005-01-01

    This paper explores how two Danish rehabilitation organizations textual guidelines for assessment of clients’ personality traits influence the actual evaluation of clients. The analysis will show how staff members produce institutional identities corresponding to organizational categories, which very often have little or no relevance for the clients evaluated. The goal of the article is to demonstrate how the institutional complex that frames the work of the organizations produces the client ...

  16. Evaluation system for CO2 emission of hot asphalt mixture

    Directory of Open Access Journals (Sweden)

    Bo Peng

    2015-04-01

    Full Text Available The highway construction industry plays an important role in economic and development, but is also a primary source of carbon emission. Accordingly, with the global climate change, energy conservation and reduction of carbon emissions have become critical issues in the highway construction industry. However, to date, a model for the highway construction industry has not been established. Hence, to implement a low-carbon construction model for highways, this study divided asphalt pavement construction into aggregate stacking, aggregate supply, and other stages, and compiled a list of energy consumption investigation. An appropriate calculation model of CO2 emission was then built. Based on the carbon emission calculation model, the proportion of carbon emissions in each stage was analyzed. The analytic hierarchy process was used to establish the system of asphalt pavement construction with a judgment matrix, thereby enabling calculation of the weight coefficient of each link. In addition, the stages of aggregate heating, asphalt heating, and asphalt mixture mixing were defined as key stages of asphalt pavement construction. Carbon emissions at these stages accounted for approximately 90% of the total carbon emissions. Carbon emissions at each stage and their impact on the environment were quantified and compared. The energy saving construction schemes as well as the environmental and socioeconomic benefits were then proposed. Through these schemes, significant reductions in carbon emissions and costs can be achieved. The results indicate that carbon emissions reduce by 32.30% and 35.93%, whereas costs reduce by 18.58% and 6.03%. The proposed energy-saving and emission reduction scheme can provide a theoretical basis and technical support for the development of low-carbon highway construction.

  17. Mechanical Properties of Warm Mix Asphalt Prepared Using Foamed Asphalt Binders

    Science.gov (United States)

    2011-03-01

    Warm mix asphalt (WMA) is a name given to a group of technologies that have the common purpose of reducing the viscosity : of the asphalt binders. This reduction in viscosity offers the advantage of producing asphalt-aggregate mixtures at lower mixin...

  18. Attribution of aerosol radiative forcing over India during the winter monsoon to emissions from source categories and geographical regions

    Science.gov (United States)

    Verma, S.; Venkataraman, C.; Boucher, O.

    2011-08-01

    We examine the aerosol radiative effects due to aerosols emitted from different emission sectors (anthropogenic and natural) and originating from different geographical regions within and outside India during the northeast (NE) Indian winter monsoon (January-March). These studies are carried out through aerosol transport simulations in the general circulation (GCM) model of the Laboratoire de Météorologie Dynamique (LMD). The model estimates of aerosol single scattering albedo (SSA) show lower values (0.86-0.92) over the region north to 10°N comprising of the Indian subcontinent, Bay of Bengal, and parts of the Arabian Sea compared to the region south to 10°N where the estimated SSA values lie in the range 0.94-0.98. The model estimated SSA is consistent with the SSA values inferred through measurements on various platforms. Aerosols of anthropogenic origin reduce the incoming solar radiation at the surface by a factor of 10-20 times the reduction due to natural aerosols. At the top-of-atmosphere (TOA), aerosols from biofuel use cause positive forcing compared to the negative forcing from fossil fuel and natural sources in correspondence with the distribution of SSA which is estimated to be the lowest (0.7-0.78) from biofuel combustion emissions. Aerosols originating from India and Africa-west Asia lead to the reduction in surface radiation (-3 to -8 W m -2) by 40-60% of the total reduction in surface radiation due to all aerosols over the Indian subcontinent and adjoining ocean. Aerosols originating from India and Africa-west Asia also lead to positive radiative effects at TOA over the Arabian Sea, central India (CNI), with the highest positive radiative effects over the Bay of Bengal and cause either negative or positive effects over the Indo-Gangetic plain (IGP).

  19. Process of preparing asphalt bodies, etc

    Energy Technology Data Exchange (ETDEWEB)

    Klever, H W

    1924-05-03

    A process for the preparation of asphaltic bodies is characterized in that bituminous minerals such as oil-shale, coal, etc. are submitted to a heating process, with or without pressure, which is so mild that asphaltic bodies result and petroleum and tar oils are formed only in small amounts, and that the asphaltic bodies are used either together with the mineral constituents or after filtration from the latter.

  20. Operational properties of nanomodified stone mastic asphalt

    OpenAIRE

    Inozemtsev Sergey Sergeevich; Korolev Evgeniy Valer’evich

    2015-01-01

    In order to prolong the lifetime and to improve the quality of pavements made of asphalt concrete it is necessary to apply innovative solutions in the process of design of such building materials. In order to solve the problem of low durability of asphalt concrete a modifier was proposed, which consists of diatomite, iron hydroxide sol (III) and silica sol. Application of the diatomite with nanoscale layer of nanomodifier allows getting a stone mastic asphalt, which has high values of physica...

  1. Final Rule to Reduce Toxic Air Emissions from Asphalt Processing and Asphalt Roofing Manufacturing Facilities Fact Sheet

    Science.gov (United States)

    This page contains a February 2003 fact sheet with information regarding the National Emissions Standards for Hazardous Air Pollutants (NESHAP) for Asphalt Processing and Asphalt Roofing Manufacturing.

  2. Modified asphalt for pavements; Hosoyo kaishitsu asufuaruto ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Tsukagoshi, T. [Nippon Oil Co. Ltd., Yokohama (Japan)

    1997-10-01

    Modified asphalt has been used widely in such applications as countermeasure against rutting, countermeasure against wear caused by tire chains in snowy and cold areas, or bridge deck pavement. Features of various kinds of modified asphalt, standards, and standard properties are introduced. Modified asphalt containing natural asphalt is used for steel plate deck pavement. Semi-blown asphalt is used when emphasis must be given to the countermeasure for flowing resistance of asphalt pavement. Features and standards of asphalt containing rubber, thermoplastic elastomer, and thermoplastic resin are described. Asphalt containing heat-setting resin shows excellent characteristics, which other types of modified asphalt do not possess, in the laboratory resistance test for fatigue, flowing, and wear. Change in the history of modified asphalt in Japan from the initial stage to the present are explained and shown in a table together with time and phenomena, and the change in the production of modified asphalt is shown. 15 refs., 5 figs., 5 tabs.

  3. Process of coagulating asphalts, etc

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffer, J A; Pfersch, G

    1931-03-28

    The present invention has for its object a process of deasphaltizing and deparaffining applicable to mixtures of hydrocarbons such as crude mineral oils and tars obtained under the influence of heat from shales, lignites, peats, and similar products, to natural bitumens and those obtained by extraction with organic solvents and also all those derived from the substances, the process in question having the following characteristics: the coagulation or the precipitation of the asphaltic material, the resinous material, and the asphaltic and resinous material, which is found in the colloidal state or any other state in the substances given above, is obtained by the addition of a small amount of solvent and of acids or mixtures of acids.

  4. Aging of Rejuvenated Asphalt Binders

    Directory of Open Access Journals (Sweden)

    Mojtaba Mohammadafzali

    2017-01-01

    Full Text Available An important concern that limits the RAP content in asphalt mixtures is the fact that the aged binder that is present in the RAP can cause premature cracking. Rejuvenators are frequently added to high RAP mixtures to enhance the properties of the binder. There is no existing method to predict the longevity of a rejuvenated asphalt. This study investigated the aging of rejuvenated binders and compared their durability with that of virgin asphalt. Various samples with different types and proportions of RAP, virgin binder, and rejuvenator were aged by RTFO and three cycles of PAV. DSR and BBR tests were conducted to examine the high-temperature and low-temperature rheological properties of binders. Results indicated that the type and dosage of the rejuvenator have a great influence on the aging rate and durability of the binder. Some rejuvenators make the binder age slower, while others accelerate aging. These observations confirm the importance of evaluating the long-term aging of recycled binders. For this purpose, critical PAV time was proposed as a measure of binder’s longevity.

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

    Science.gov (United States)

    Sanchez Ramos, Jorge Luis

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

  6. Consumer Product Category Database

    Science.gov (United States)

    The Chemical and Product Categories database (CPCat) catalogs the use of over 40,000 chemicals and their presence in different consumer products. The chemical use information is compiled from multiple sources while product information is gathered from publicly available Material Safety Data Sheets (MSDS). EPA researchers are evaluating the possibility of expanding the database with additional product and use information.

  7. Regional implementation of warm mix asphalt.

    Science.gov (United States)

    2014-09-01

    Asphalt is used in over 94 percent of all paved roadways in the United States. The ability to reduce its cost and emissions : while improving its performance has benefits that could potentially change the direction the asphalt industry moves toward i...

  8. Laboratory evaluation of warm mix asphalt.

    Science.gov (United States)

    2011-09-14

    "Hot Mix Asphalt (HMA) has been traditionally produced at a discharge temperature of between : 280F (138C) and 320 F (160C), resulting in high energy (fuel) costs and generation of greenhouse : gases. The goal for Warm Mix Asphalt (WMA) is to...

  9. Hot Mix Asphalt Recycling : Practices and Principles

    NARCIS (Netherlands)

    Mohajeri, M.

    2015-01-01

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

  10. Mix Proportion Design of Asphalt Concrete

    Science.gov (United States)

    Wu, Xianhu; Gao, Lingling; Du, Shoujun

    2017-12-01

    Based on the gradation of AC and SMA, this paper designs a new type of anti slide mixture with two types of advantages. Chapter introduces the material selection, ratio of ore mixture ratio design calculation, and determine the optimal asphalt content test and proportioning design of asphalt concrete mix. This paper introduces the new technology of mix proportion.

  11. Advanced evaluation of asphalt mortar for induction healing purposes

    NARCIS (Netherlands)

    Apostolidis, P.; Liu, X.; Scarpas, Athanasios; Kasbergen, C.; van de Ven, M.F.C.

    2016-01-01

    Induction heating technique is an innovative asphalt pavement maintenance method that is applied to inductive asphalt concrete mixes in order to prevent the formation of macro-cracks by increasing locally the temperature of asphalt. The development of asphalt mixes with improved electrical and

  12. Latex improvement of recycled asphalt pavement

    Science.gov (United States)

    Drennon, C.

    1982-08-01

    The performance of a single unmodified milled recycled asphalt concrete was compared to milled asphalt concrete modified by addition of three types of rubber latex. Latex was added at 2, 3, 5, and 8 percent latex by weight of asphalt in the asphalt concrete. Lattices used were a styrene butadiene (SBR), a natural rubber (NR), an acrylonitrile butadiene (NBR), and four varieties of out of specification SBR lattices. Marshall tests, while indecisive, showed a modest improvement in properties of SBR and NR added material at 3 and 5 percent latex. Addition of NBR latex caused deterioration in Marshall stability and flow over that of control. Repeated load tests were run using the indirect tensile test, analyzed by the VESYS program, which computes life of pavements. Repeated load tests showed improvement in asphalt concrete life when 3 and 5 percent SBR was added. Improvement was also shown by the out of specification SBR.

  13. Rubber modification of asphalt binders and mixes

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, G.; Hesp, S.A.M. [Queen`s Univ., Kingston, ON (Canada). Dept. of Chemistry

    1995-12-31

    The physical properties of asphalt binders and concrete, modified with waste rubber tire, were examined. In an experiment designed to address the concern of waste disposal of scrap rubber, a control asphalt, devulcanized rubber modified asphalt and a crumb rubber modified asphalt were used to make asphalt concrete mixes. The three mixes were subjected to a thermal stress test to determine their low temperature fracture temperatures and strengths. Results were discussed in terms of the binder material used. At high service temperatures, the addition of 10% devulcanized rubber was found to have no beneficial effect, whereas the addition of 10% 80 mesh crumb rubber produced a modest improvement in performance. At low temperatures, the addition of devulcanized rubber produced increased resistance to cracking up to 90%. The addition of 10% 80 mesh crumb rubber increased fracture toughness by a factor of 3.3 times. 12 refs., 3 tabs.

  14. Identification and characterization of five non-traditional-source categories: Catastrophic/accidental releases, vehicle repair facilities, recycling, pesticide application, and agricultural operations. Final report, September 1991-September 1992

    International Nuclear Information System (INIS)

    Sleva, S.; Pendola, J.A.; McCutcheon, J.; Jones, K.; Kersteter, S.L.

    1993-03-01

    The work is part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plans (SIP) area source methodologies and to develop appropriate emissions estimation methodologies and emission factors for a group of these source categories. Based on the results of the identification and characterization portions of the research, five source categories were selected for methodology and emission factor development: catastrophic/accidental releases, vehicle repair facilities, recycling, pesticide application and agricultural operations. The report presents emissions estimation methodologies and emission factor data for the selected source categories. The discussions for each selected category include general background information, emissions generation activities, pollutants emitted, sources of activity and pollutant data, emissions estimation methodologies, issues to be considered and recommendations. The information used in these discussions was derived from various sources including available literature, industrial and trade association publications and contracts, experts on the category and activity, and knowledgeable federal and state personnel

  15. Modelling of Asphalt Concrete Stiffness in the Linear Viscoelastic Region

    Science.gov (United States)

    Mazurek, Grzegorz; Iwański, Marek

    2017-10-01

    Stiffness modulus is a fundamental parameter used in the modelling of the viscoelastic behaviour of bituminous mixtures. On the basis of the master curve in the linear viscoelasticity range, the mechanical properties of asphalt concrete at different loading times and temperatures can be predicted. This paper discusses the construction of master curves under rheological mathematical models i.e. the sigmoidal function model (MEPDG), the fractional model, and Bahia and co-workers’ model in comparison to the results from mechanistic rheological models i.e. the generalized Huet-Sayegh model, the generalized Maxwell model and the Burgers model. For the purposes of this analysis, the reference asphalt concrete mix (denoted as AC16W) intended for the binder coarse layer and for traffic category KR3 (5×105 controlled strain mode. The fixed strain level was set at 25με to guarantee that the stiffness modulus of the asphalt concrete would be tested in a linear viscoelasticity range. The master curve was formed using the time-temperature superposition principle (TTSP). The stiffness modulus of asphalt concrete was determined at temperatures 10°C, 20°C and 40°C and at loading times (frequency) of 0.1, 0.3, 1, 3, 10, 20 Hz. The model parameters were fitted to the rheological models using the original programs based on the nonlinear least squares sum method. All the rheological models under analysis were found to be capable of predicting changes in the stiffness modulus of the reference asphalt concrete to satisfactory accuracy. In the cases of the fractional model and the generalized Maxwell model, their accuracy depends on a number of elements in series. The best fit was registered for Bahia and co-workers model, generalized Maxwell model and fractional model. As for predicting the phase angle parameter, the largest discrepancies between experimental and modelled results were obtained using the fractional model. Except the Burgers model, the model matching quality was

  16. Evaluation of Thermal Oxidative Aging Effect on the Rheological Performance of Modified Asphalt Binders

    Science.gov (United States)

    Zhu, Cheng

    indexes. The modifiers-SBS and TR have different directional effect on these parameters. The field asphalt binder carbonyl area prediction was conducted. The pavement temperatures which were calculated by TEMP software were input into MATLAB(TM) as a parameter with other factors, e.g the asphalt binder oxidative aging parameters, the binder film thickness, the air void radius, etc., to calculate the field asphalt CA value as a function of time out to 20 years. It was found that the different rheological index method resulted different conclusion with the asphalt binder. The SBS modified asphalt binders of A, C version and B version had close average increasing rate of LSV, higher average decreasing rate of G*c, lower average increasing rate of DSR Fn compared with the corresponding base binders. D_HPM had lower average increasing rate of LSV, G*c and DSR Fn than base binder Base D. The tire rubber modified binder B_TR had higher average increasing rate of LSV, DSR Fn, and higher average decreasing rate of G*c than base binder Base B. The main finding of this study was that the modifier SBS and tire rubber can reduce the thermal oxidation aging rate (kf and kc) compared with the corresponding base binder, the activation energy was asphalt binder source dependent. For the hardening susceptibility, the modifiers-SBS, X, Y, Z reduced the HS of LSV and G-R. The tire rubber slightly increased the HS of LSV and G-R. A_PM, B_TR_X_PM reduced the HS of G*c and other modified binders increased the HS of G*c.

  17. About Coloured Cold Asphaltic Mixtures

    Directory of Open Access Journals (Sweden)

    Loredana Judele

    2008-01-01

    Full Text Available The first coloured bitumen was obtained by using bitumen from Peru and then bitumen from the Middle East, with a low content of asphaltenes, also called "colourable" bitumens. The colours obtained by adding iron oxides led nevertheless to dark colours, due to the presence of asphaltenes. Nowadays the coloured asphalt is obtained from synthesis binders with translucent aspect. The colours are obtained by adding inorganic pigments, mainly iron oxide for red, chromic oxide for green, titanic dioxide for white. The properties and behaviour of the coloured bitumen during its lifetime are comparable with the ones of classic bitumen, sometimes even better.

  18. Properties of Direct Coal Liquefaction Residue Modified Asphalt Mixture

    Directory of Open Access Journals (Sweden)

    Jie Ji

    2017-01-01

    Full Text Available The objectives of this paper are to use Direct Coal Liquefaction Residue (DLCR to modify the asphalt binders and mixtures and to evaluate the performance of modified asphalt mixtures. The dynamic modulus and phase angle of DCLR and DCLR-composite modified asphalt mixture were analyzed, and the viscoelastic properties of these modified asphalt mixtures were compared to the base asphalt binder SK-90 and Styrene-Butadiene-Styrene (SBS modified asphalt mixtures. The master curves of the asphalt mixtures were shown, and dynamic and viscoelastic behaviors of asphalt mixtures were described using the Christensen-Anderson-Marasteanu (CAM model. The test results show that the dynamic moduli of DCLR and DCLR-composite asphalt mixtures are higher than those of the SK-90 and SBS modified asphalt mixtures. Based on the viscoelastic parameters of CAM models of the asphalt mixtures, the high- and low-temperature performance of DLCR and DCLR-composite modified asphalt mixtures are obviously better than the SK-90 and SBS modified asphalt mixtures. In addition, the DCLR and DCLR-composite modified asphalt mixtures are more insensitive to the frequency compared to SK-90 and SBS modified asphalt mixtures.

  19. Neutron thermalization in quality control of asphalts content in mixtures for paving. Adaptation of nuclear densimeters for this purpose

    International Nuclear Information System (INIS)

    Bravo R, T.; Montanez M, P.O.

    1995-01-01

    This paper shows how the neutron source of the nuclear densimeters, used for measure the humidity, can be used for measuring and making the quality control of the asphalt percentage in mixtures used for street paving. The measures are based in the neutronic thermalization processes, because the hydrogen is the main part of chemical composition of the asphalts. A calibration method for the equipment is presented. (author). 6 refs, 3 figs, 3 tabs

  20. Recycling of rubber tires in asphalt paving materials

    Energy Technology Data Exchange (ETDEWEB)

    Piggott, M.R.; Woodhams, R.T.

    1979-01-01

    It has been known that the addition of rubber to asphalt used in paving will produced markedly superior road surfaces. Partly because of cost and because of the nonconventional paving techniques necessary, rubber has been largely ignored as a practical paving additive except in special cases. However, the large accumulation of old tires existing today provides a ready source for suitable rubber. If ground into a fine powder, this rubber can be mixed in a conventional pug mill along with sand, stone and asphalt to produce a hot mix which can be aplied in the normal manner without any special techniques. The extra cost of such modification is only 1% of a typical paving contract, whereas the advantages include lower maintenance cost, more durable road surface, and elimination of unwanted waste tires. This report has been prepared to assist civic and other authorities in the development of improved road surfacing formulations through the reuse of old tires. It includes the results of paving trials in Toronto and laboratory evaluations. These tests show that the addition of powdered rubber to asphalt paving materials markedly improves the durability and crack resistance, particularly at low temperatures. Additives in the rubber impart good strength retention in the presence of moisture. The toughness increases with age due to a slow interaction of the rubber with the asphalt which is accompanied by an increase in viscosity. As a result, performance is also enhanced at high temperatures and helps to minimize pavement distortions due to hot weather and traffic. 16 refs., 18 figs., 2 tabs.

  1. Evaluation of Different Mineral Filler Aggregates for Asphalt Mixtures

    Science.gov (United States)

    Wasilewska, Marta; Małaszkiewicz, Dorota; Ignatiuk, Natalia

    2017-10-01

    Mineral filler aggregates play an important role in asphalt mixtures because they fill voids in paving mix and improve the cohesion of asphalt binder. Limestone powder containing over 90% of CaCO3 is the most frequently used type of filler. Waste material from the production of coarse aggregate can be successfully used as a mineral filler aggregate for hot asphalt concrete mixtures as the limestone powder replacement. This paper presents the experimental results of selected properties of filler aggregates which were obtained from rocks with different mineral composition and origin. Five types of rocks were used as a source of the mineral filler aggregate: granite, gabbro, trachybasalt, quartz sandstone and rocks from postglacial deposits. Limestone filler was used in this study as the reference material. The following tests were performed: grading (air jet sieving), quality of fines according to methylene blue test, water content by drying in a ventilated oven, particle density using pyknometer method, Delta ring and ball test, Bitumen Number, fineness determined as Blaine specific surface area. Mineral filler aggregates showed significant differences when they were mixed with bitumen and stiffening effect in Delta ring and ball test was evaluated. The highest values were achieved when gabbro and granite fillers were used. Additionally, Scanning Electron Microscopy (SEM) analysis of grain shape and size was carried out. Significant differences in grain size and shape were observed. The highest non-homogeneity in size was determined for quartz sandstone, gabbro and granite filler. Their Blaine specific surface area was lower than 2800 cm2/g, while for limestone and postglacial fillers with regular and round grains it exceeded 3000 cm2/g. All examined mineral filler aggregates met requirements of Polish National Specification WT-1: 2014 and could be used in asphalt mixtures.

  2. Electrical and mechanical properties of asphalt concrete containing conductive fibers and fillers

    NARCIS (Netherlands)

    Wang, H.; Yang, Jun; Liao, Hui; Chen, Xianhua

    2016-01-01

    Electrically conductive asphalt concrete has the potential to satisfy multifunctional applications. Designing such asphalt concrete needs to balance the electrical and mechanical performance of asphalt concrete. The objective of this study is to design electrically conductive asphalt concrete

  3. RELATIONSHIP BETWEEN FOAMING BEHAVIOR AND SURFACE ENERGY OF ASPHALT BINDER

    Directory of Open Access Journals (Sweden)

    Jian-ping Xu

    2017-12-01

    Full Text Available To solve the problem of insufficiency in microscopic performance of foamed asphalt binder, surface energy theory was utilized to analyze the foaming behavior and wettability of asphalt binder. Based on the surface energy theory, the Wilhelmy plate method and universal sorption device method were employed to measure the surface energy components of asphalt binders and aggregates, respectively. Combined with the traditional evaluation indictor for foamed asphalt, the relationship between the foaming property and surface energy of asphalt binder was analyzed. According to the surface energy components, the wettability of asphalt binder to aggregate was calculated to verify the performance of foamed asphalt mixture. Results indicate that the foaming behavior of asphalt will be influenced by surface energy, which will increase with the decline of surface energy. In addition, the surface energy of asphalt binder significantly influences the wettability of asphalt binder to aggregates. Meanwhile, there is an inversely proportional relationship between surface energy of asphalt binder and wettability. Therefore, it can be demonstrated that surface energy is a good indictor which can be used to evaluate the foaming behavior of the asphalt binder. And it is suggested to choose the asphalt binder with lower surface energy in the process of design of foamed asphalt mixture.

  4. Method of reprocessing radioactive asphalt solidification products

    International Nuclear Information System (INIS)

    Nakaya, Iwao; Murakami, Tadashi; Miyake, Takafumi; Inagaki, Yuzo.

    1986-01-01

    Purpose: To obtain heat-stable solidification products and decrease the total volume thereof by modifying the solidified form by the reprocessing of existent radioactive asphalt solidification products. Method: Radioactive asphalt solidification products are heated into a fluidized state. Then, incombustible solvents such as perchloroethylene or trichloroethylene are added to a dissolving tank to gradually dissolve the radioactive asphalt solidification products. Thus, organic materials such as asphalts are transferred into the solvent layer, while inorganic materials containing radioactive materials remain as they are in the separation tank. Then, the inorganic materials containing the radioactive materials are taken out and then solidified, for example, by converting them into a rock or glass form. (Kawakami, Y.)

  5. Evaluation of asphalt treated permeable base.

    Science.gov (United States)

    2013-12-01

    III : Tec : hnical : Report Documentation Page : 1. Report No. : 2. Government Accession : No. : 3. Recipient's Catalog No : . : 201 : 3 : - : 09 : - : - : - : - : - : - : 4. Title and Subtitle : 5. Report Date : Evaluation of Asphalt Treated Permeab...

  6. Properties of sulfur-extended asphalt concrete

    Directory of Open Access Journals (Sweden)

    Gladkikh Vitaliy

    2016-01-01

    Full Text Available Currently, increased functional reliability of asphalt concrete coatings associated with various modifying additives that improve the durability of pavements. Promising builder is a technical sulfur. Asphalt concrete, made using a complex binder consisting of petroleum bitumen and technical sulfur, were calledsSulfur-Extended Asphalt Concrete. Such asphalt concrete, due to changes in the chemical composition of particulate and bitumen, changes the intensity of the interaction at the interface have increased rates of physical and mechanical properties. There was a lack of essential knowledge concerning mechanical properties of the sulfur-bituminous concrete with such an admixture; therefore, we had carried out the necessary examination. It is revealed that a new material satisfies local regulations in terms of compressive and tensile strength, shear resistance, and internal friction.

  7. Low temperature rheological properties of asphalt mixtures containing different recycled asphalt materials

    Directory of Open Access Journals (Sweden)

    Ki Hoon Moon

    2017-01-01

    Full Text Available Reclaimed Asphalt Pavement (RAP and Recycled Asphalt Shingles (RAS are valuable materials commonly reused in asphalt mixtures due to their economic and environmental benefits. However, the aged binder contained in these materials may negatively affect the low temperature performance of asphalt mixtures. In this paper, the effect of RAP and RAS on low temperature properties of asphalt mixtures is investigated through Bending Beam Rheometer (BBR tests and rheological modeling. First, a set of fourteen asphalt mixtures containing RAP and RAS is prepared and creep stiffness and m-value are experimentally measured. Then, thermal stress is calculated and graphically and statistically compared. The Huet model and the Shift-Homothety-Shift in time-Shift (SHStS transformation, developed at the École Nationale des Travaux Publics de l'État (ENTPE, are used to back calculate the asphalt binder creep stiffness from mixture experimental data. Finally, the model predictions are compared to the creep stiffness of the asphalt binders extracted from each mixture, and the results are analyzed and discussed. It is found that an addition of RAP and RAS beyond 15% and 3%, respectively, significantly change the low temperature properties of asphalt mixture. Differences between back-calculated results and experimental data suggest that blending between new and old binder occurs only partially. Based on the recent finding on diffusion studies, this effect may be associated to mixing and blending processes, to the effective contact between virgin and recycled materials and to the variation of the total virgin-recycled thickness of the binder film which may significantly influence the diffusion process. Keywords: Reclaimed Asphalt Pavement (RAP, Recycled Asphalt Shingles (RAS, Thermal stress, Statistical comparison, Back-calculation, Binder blending

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

    Science.gov (United States)

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

    2016-08-01

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

  9. Evaluation of Asphalt Mixture Low-Temperature Performance in Bending Beam Creep Test.

    Science.gov (United States)

    Pszczola, Marek; Jaczewski, Mariusz; Rys, Dawid; Jaskula, Piotr; Szydlowski, Cezary

    2018-01-10

    Low-temperature cracking is one of the most common road pavement distress types in Poland. While bitumen performance can be evaluated in detail using bending beam rheometer (BBR) or dynamic shear rheometer (DSR) tests, none of the normalized test methods gives a comprehensive representation of low-temperature performance of the asphalt mixtures. This article presents the Bending Beam Creep test performed at temperatures from -20 °C to +10 °C in order to evaluate the low-temperature performance of asphalt mixtures. Both validation of the method and its utilization for the assessment of eight types of wearing courses commonly used in Poland were described. The performed test indicated that the source of bitumen and its production process (and not necessarily only bitumen penetration) had a significant impact on the low-temperature performance of the asphalt mixtures, comparable to the impact of binder modification (neat, polymer-modified, highly modified) and the aggregate skeleton used in the mixture (Stone Mastic Asphalt (SMA) vs. Asphalt Concrete (AC)). Obtained Bending Beam Creep test results were compared with the BBR bitumen test. Regression analysis confirmed that performing solely bitumen tests is insufficient for comprehensive low-temperature performance analysis.

  10. Characterization of effects of thermal property of aggregate on the carbon footprint of asphalt industries in China

    Directory of Open Access Journals (Sweden)

    Ali Jamshidi

    2017-04-01

    Full Text Available In this study, the effects of the thermal properties of asphalt binders and aggregate materials were characterized in terms of the specific heat capacity (C for energy consumption and environmental footprints of hot mix asphalt (HMA and warm mix asphalt (WMA. Asphalt mixes produced using low-C aggregate are found to be more energy-efficient and environmental friendly, irrespective of the binder type and construction technology. Therefore, different fractions of aggregate blends were replaced with the aggregate provided from a low-C source or sustainable source. Analysis of energy consumption clearly indicated that the specific energy and environmental footprints decrease linearly as the low-C aggregate content increases. The amount of energy saving realized in the asphalt industries by the use of low-C aggregate is significant on a national scale in China. In this regard, China was chosen as a case study. Analysis of fuel requirement clearly indicated that the production of WMA using high thermal sensitivity aggregate can yield significant energy saving sufficient to fuel 44,007 to 664,880 Chinese households per year. Therefore, use of low C aggregate in asphalt mix production can be adopted as a strategy to produce WMA and HMA.

  11. Fatigue Behavior of Modified Asphalt Concrete Pavement

    Directory of Open Access Journals (Sweden)

    saad I. Sarsam

    2016-02-01

    Full Text Available Fatigue cracking is the most common distress in road pavement. It is mainly due to the increase in the number of load repetition of vehicles, particularly those with high axle loads, and to the environmental conditions. In this study, four-point bending beam fatigue testing has been used for control and modified mixture under various micro strain levels of (250 μƐ, 400 μƐ, and 750 μƐ and 5HZ. The main objective of the study is to provide a comparative evaluation of pavement resistance to the phenomenon of fatigue cracking between modified asphalt concrete and conventional asphalt concrete mixes (under the influence of three percentage of Silica fumes 1%, 2%, 3% by the weight of asphalt content, and (changing in the percentage of asphalt content by (0.5% ± from the optimum. The results show that when Silica fumes content was 1%, the fatigue life increases by 17%, and it increases by 46% when Silica fumes content increases to 2%, and that fatigue life increases to 34 % when Silica fumes content increases to 3% as compared with control mixture at (250 μƐ, 20°C and optimum asphalt content. From the results above, we can conclude the optimum Silica fumes content was 2%. When the asphalt content was 4.4%, the fatigue life has increased with the use of silica fumes by (50%, when asphalt content was 5.4%, the additives had led to increasing the fatigue life by (69%, as compared with the conventional asphalt concrete pavement.

  12. Observation of asphalt binder microstructure with ESEM.

    Science.gov (United States)

    Mikhailenko, P; Kadhim, H; Baaj, H; Tighe, S

    2017-09-01

    The observation of asphalt binder with the environmental scanning electron microscope (ESEM) has shown the potential to observe asphalt binder microstructure and its evolution with binder aging. A procedure for the induction and identification of the microstructure in asphalt binder was established in this study and included sample preparation and observation parameters. A suitable heat-sampling asphalt binder sample preparation method was determined for the test and several stainless steel and Teflon sample moulds developed, finding that stainless steel was the preferable material. The magnification and ESEM settings conducive to observing the 3D microstructure were determined through a number of observations to be 1000×, although other magnifications could be considered. Both straight run binder (PG 58-28) and an air blown oxidised binder were analysed; their structures being compared for their relative size, abundance and other characteristics, showing a clear evolution in the fibril microstructure. The microstructure took longer to appear for the oxidised binder. It was confirmed that the fibril microstructure corresponded to actual characteristics in the asphalt binder. Additionally, a 'bee' micelle structure was found as a transitional structure in ESEM observation. The test methods in this study will be used for more comprehensive analysis of asphalt binder microstructure. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  13. Operational properties of nanomodified stone mastic asphalt

    Directory of Open Access Journals (Sweden)

    Inozemtsev Sergey Sergeevich

    2015-03-01

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

  14. Use of Adhesion Promoters in Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Cihlářová Denisa

    2018-03-01

    Full Text Available The purpose of asphalt binder as a significant binder in road constructions is to permanently bind aggregates of different compositions and grain sizes. The asphalt binder itself does not have suitable adhesiveness, so after a period of time, bare grains can appear. This results in a gradual separation of the grains from an asphalt layer and the presence of potholes in a pavement. Adhesion promoters or adhesive agents are important and proven promoters in practice. They are substances mainly based on the fatty acids of polyamides which should increase the reliability of the asphalt’s binder adhesion to the aggregates, thus increasing the lifetime period of the asphalt mixture as well as its resistance to mechanical strain. The amount of a promoter or agent added to the asphalt mixture is negligible and constitutes about 0.3% of the asphalt’s binder weight. Nevertheless, even this quantity significantly increases the adhesive qualities of an asphalt binder. The article was created in cooperatation with the Slovak University of Technology, in Bratislava, Slovakia, and focuses on proving the new AD2 adhesive additive and comparing it with the Addibit and Wetfix BE promoters used on aggregates from the Skuteč - Litická and Bystřec quarries.

  15. 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.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  17. Durability of European Asphalt Mixtures Containing Reclaimed Asphalt and Warm-Mix Additives

    NARCIS (Netherlands)

    Varveri, A.; Avgerinopoulos, S.; Scarpas, Athanasios

    2016-01-01

    This paper investigates the moisture susceptibility of European asphalt mixtures (SMA) containing reclaimed asphalt (RA) and warm mix (WMA) additives. Test sections of a typical SMA mixture have been laid, from which cylindrical samples were cored and utilized for laboratory testing. Four variants

  18. 40 CFR 443.40 - Applicability; description of the linoleum and printed asphalt felt subcategory.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Applicability; description of the linoleum and printed asphalt felt subcategory. 443.40 Section 443.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS EFFLUENT LIMITATIONS GUIDELINES FOR EXISTING SOURCES AND STANDARDS OF PERFORMANC...

  19. Experimental studies of biodegradation of asphalt by microorganisms

    International Nuclear Information System (INIS)

    Mine, Tatsuya; Mihara, Morihiro; Ooi, Takao; Lin, Kong-hua; Kawakami, Yasushi

    2000-04-01

    On the geological disposal system of the radioactive wastes, the activities of the microorganisms that could degrade the asphalt might be significant for the assessment of the system performance. As the main effects of the biodegradation of the asphalt, the fluctuation of leaching behavior of the nuclides included in asphalt waste has been indicated. In this study, the asphalt biodegradation test was carried out. The microorganism of which asphalt degradation ability was comparatively higher under aerobic condition and anaerobic condition was used. The asphalt biodegradation rate was calculated and it was evaluated whether the asphalt biodegradation in this system could occur. The results show that the asphalt biodegradation rate under anaerobic and high alkali condition will be 300 times lower than under aerobic and neutral pH. (author)

  20. Preparation and rheological behavior of polymer-modified asphalts

    Science.gov (United States)

    Yousefi, Ali Akbar

    1999-09-01

    Different materials and methods were used to prepare and stabilize polymer-modified asphalts. Addition of thermoplastic elastomers improved some technically important properties of asphalt. Due to inherent factors like large density difference between asphalt and polyethylene, many physical methods in which the structure of asphalt is unchanged, failed to stabilize this system. The effect of addition of copolymers and a pyrolytic oil residue derived from used tire rubber were also studied and found to be ineffective on the storage stability of the polymer-asphalt emulsions while high and moderate temperature properties of the asphalt were found to be improved. Finally, the technique of catalytic grafting of polymer on the surface of high-density particles (e.g. carbon black) was used to balance the large density difference between asphalt and polymer. The resulting polymer-asphalts were stable at high temperatures and showed enhanced properties at low and high temperatures.

  1. Investigating the creep properties of asphaltic concrete containing ...

    Indian Academy of Sciences (India)

    Hasan Taherkhani

    2018-03-10

    Mar 10, 2018 ... A three-stage model, developed was fitted to the dynamic ... This indicates that the rutting resistance of such asphalt ... drug delivery [23]. .... Different mathematical ... viour of asphaltic materials and prediction of flow number. A.

  2. Determination of usable residual asphalt binder in RAP.

    Science.gov (United States)

    2009-01-01

    For current recycled mix designs, the Illinois Department of Transportation (IDOT) assumes 100% contribution of : working binder from Recycled Asphalt Pavement (RAP) materials when added to Hot Mix Asphalt (HMA). However, it is : unclear if this assu...

  3. Comparison of winter temperature profiles in asphalt and concrete pavements.

    Science.gov (United States)

    2014-06-01

    The objectives of this research were to 1) determine which pavement type, asphalt or concrete, has : higher surface temperatures in winter and 2) compare the subsurface temperatures under asphalt and : concrete pavements to determine the pavement typ...

  4. Terrestrial radiation level in selected asphalt plants in Port Harcourt ...

    African Journals Online (AJOL)

    Terrestrial radiation level in selected asphalt plants in Port Harcourt, Nigeria. ... An environmental radiation survey in asphalt processing plants in Rivers State was been carried out ... Therefore the results show significant radiological risk.

  5. Appropriate models for estimating stresses and strains in asphalt layers

    CSIR Research Space (South Africa)

    Jooste, FJ

    1998-09-01

    Full Text Available The broad objective is to make recommendations for appropriate modelling procedures to be used in the structural design of asphalt layers. Findings of this investigation are intended to be used in refining and validating existing asphalt pavement...

  6. Asphalt mix characterization using dynamic modulus and APA testing.

    Science.gov (United States)

    2005-11-01

    final report summarizes two research efforts related to asphalt mix characterization: dynamic modulus and Asphalt Pavement Analyzer testing. One phase of the research consisted of a laboratory-based evaluation of dynamic modulus of Oregon dense-grade...

  7. Performance assessment of warm mix asphalt (WMA) pavements.

    Science.gov (United States)

    2009-09-01

    Warm Mix Asphalt (WMA) is a new technology that was introduced in Europe in 1995. WMA offers several advantages over : conventional asphalt concrete mixtures, including: reduced energy consumption, reduced emissions, improved or more uniform : binder...

  8. Investigation of warm-mix asphalt using Iowa aggregates.

    Science.gov (United States)

    2011-04-01

    The implementation of warm-mix asphalt (WMA) is becoming more widespread with a growing number of contractors utilizing various WMA technologies. Early research suggests WMA may be more susceptible to moisture damage than traditional hot-mix asphalt ...

  9. Utilizing Lab Tests to Predict Asphalt Concrete Overlay Performance

    Science.gov (United States)

    2017-12-01

    A series of five experimental projects and three demonstration projects were constructed to better understand the performance of pavement overlays using various levels of asphalt binder replacement (ABR) from reclaimed asphalt pavement (RAP), recycle...

  10. Effects of preparation process on performance of rubber modified asphalt

    Science.gov (United States)

    Liu, Hanbing; Luo, Guobao; Wang, Xianqiang; Jiao, Yubo

    2015-06-01

    The rational utilization of waste rubber tire is essential for the environmental protection. Utilizing rubber particles to modify asphalt can not only improve asphalt performance, but also help the recycling of waste materials. Considering the effect of different preparation process parameters on the performance of rubber modified asphalt, this paper analyzes the effects of the shear temperature, shear time and shear rate on the performance of rubber modified asphalt, and provided a reference for its preparation.

  11. Field Control and Performance of Asphalt Mixtures Containing Greater than 25 Percent Reclaimed Asphalt Pavement : Draft Final Report

    Science.gov (United States)

    2018-02-02

    The Alabama Department of Transportation (ALDOT) and other highway agencies are interested in utilization of higher percentages of reclaimed asphalt pavement (RAP) in asphalt mixtures. There are a number of research studies at both state and national...

  12. State of the art: Asphalt for airport pavement surfacing

    Directory of Open Access Journals (Sweden)

    Greg White

    2018-01-01

    Full Text Available Airport runways and taxiways are commonly comprised of a flexible pavement with an asphalt surface. Marshall-designed asphalt with sawn grooves is the most frequent airport asphalt surface material. However, some airports have adopted alternate asphalt mixtures for improved resistance to shear stress and for increased surface texture, allowing grooving to be avoided. Of the alternate asphalt mixtures, stone mastic asphalt is the most commonly reported. Resistance to shear stress is a critical performance requirement for airport surface asphalt. Shear stress resistance minimises the risk of rutting, shoving and groove closure. However, fracture resistance must not be ignored when developing even more shear resistance asphalt mixtures. Significant distress in airport asphalt surfaces, compliant with the traditional prescriptive specification, has increased interest in a performance-based airport asphalt specification. Commonly reported distresses include groove closure in slow moving aircraft areas and shearing in heavy aircraft braking zones. Development of reliable performance-indicative test methods is expected in the future and will enable warranted performance-based asphalt mixture design for airport surfaces. Keywords: Airport, Pavement, Asphalt, Surface

  13. POROUS-MASTIC ASPHALT-CONCRETE MIXTURES AND THEIR UTILIZATION HISTORY

    Directory of Open Access Journals (Sweden)

    Khudokonenko Anton Aleksandrovich

    2017-11-01

    Full Text Available Subject: a rapid increase in the traffic intensity and freight traffic on motor roads leads to premature destruction of road surfaces. At the same time, the actual service life of asphalt-concrete pavements rarely exceeds 4-5 years and in most cases is only 2-3 years. Most intensively defects and fractures appear on asphalt-concrete pavements in the early spring. Nowadays the overhaul intervals for the road surface coverings are significantly lower than those given by the regulatory requirements. One of the main reasons for this phenomenon is the use of obsolete technologies based on traditional materials whose properties are inadequate to resist stresses and deformations arising in the coating. This is especially evident in the climatic conditions of the south of the European part of Russia, where the upper layers of the roadway experience a much wider range of temperatures. Tighter requirements for the initial road-building materials and timely repair of the coatings allow us to increase the service life of motor roads. Research objectives: the aim of the study is to develop a new type of asphalt-concrete, such as porous-mastic one. Materials and methods: the work was carried out based on observations and published sources, a method of theoretical study and analysis. Results: the domestic and foreign experience of using the given asphalt concrete for the top layer of the coating was considered. The technology of preparation and laying of a porous-mastic asphalt-concrete mixture is presented and its advantages and disadvantages are shown. Conclusions: increasing the longevity of highways is an important and urgent task and it can be solved, in particular, due to the wide use of new technologies and non-traditional building materials that allow us to improve the quality of asphalt-concrete pavement and prolong its overhaul intervals.

  14. Assessment of The Asphalt Produced in Some Factories of Asphalt in Al-Hilla City

    Directory of Open Access Journals (Sweden)

    Mohammed Karem Abd

    2018-02-01

    Full Text Available The purpose of this study is to present an evaluation of  the properties and characteristics of asphalt concrete of several hot mix asphalt (HMA from five factories in Al-Hilla city. The research is divided into two parts. The first part included the laboratory analysis of samples. The second part is evaluation of results according to standard specifications.      The test results included (Asphalt content percent, stability, creep compliance, voids ratio, density, flow, crushed aggregate percent, Loss Angless abrasion and SO3 percent.The results of laboratorial tests indicated that all properties of asphalt mixes were susceptible and possible to be used in the asphaltic roads. The mixes types prepared and tested according to Marshall method. The values of Marshall stability, creep and density are (9.4, 5.4, 9.8, 9, 8.6, (2.5, 2.7, 2.7, 2.6, 2.3 and (2.334, 2.336, 2.337, 2.333, 2.338 with asphalt content between (4.2 to 4.6 % for all asphalt mixes of different factories.

  15. Sources

    International Nuclear Information System (INIS)

    Duffy, L.P.

    1991-01-01

    This paper discusses the sources of radiation in the narrow perspective of radioactivity and the even narrow perspective of those sources that concern environmental management and restoration activities at DOE facilities, as well as a few related sources. Sources of irritation, Sources of inflammatory jingoism, and Sources of information. First, the sources of irritation fall into three categories: No reliable scientific ombudsman to speak without bias and prejudice for the public good, Technical jargon with unclear definitions exists within the radioactive nomenclature, and Scientific community keeps a low-profile with regard to public information. The next area of personal concern are the sources of inflammation. This include such things as: Plutonium being described as the most dangerous substance known to man, The amount of plutonium required to make a bomb, Talk of transuranic waste containing plutonium and its health affects, TMI-2 and Chernobyl being described as Siamese twins, Inadequate information on low-level disposal sites and current regulatory requirements under 10 CFR 61, Enhanced engineered waste disposal not being presented to the public accurately. Numerous sources of disinformation regarding low level radiation high-level radiation, Elusive nature of the scientific community, The Federal and State Health Agencies resources to address comparative risk, and Regulatory agencies speaking out without the support of the scientific community

  16. Evaluating The Performance of Asphalt Concrete Mixes by Utilizing Carbon Black as Asphalt Modifier

    Directory of Open Access Journals (Sweden)

    Aliaa Faleh Al.ani

    2018-02-01

    Full Text Available Carbon black produced from several factories in Iraq is expected to provide a reinforcing agent for asphalt paving materials. Carbon black has many characteristics that distinguish  it from conventional mineral fillers, as well as their different function in pavement mixtures. Theory and exercise advanced  in the inclusive utilize of carbon black as a reinforcing agent for rubber has led to concept of asphalt reinforcement. The very fine particles of micro filler added in different contents will be dispersed in asphalt cement improving the mechanical properties of asphalt concrete mixes. In this Four percentages rates were utilized; 0, 3, 6, and 9 percent adding to asphalt grade (60-70. Mixes of asphalt concrete were destined at their optimum asphalt content (OAC then experienced to assess their engineering characteristics that contain moisture of damage, permanent deformation, modulus of resilient and characteristics of fatigue. These characteristics have been assessed utilizing indirect tensile strength, uniaxial repeated loading and repeated flexural beam tests. Mixtures improved with carbon black were existed to have amended permanent deformation and fatigue characteristics, else exhibited high resilient modulus and lower moisture susceptibility. Result showed that a rate changed from 3 to 9 percent has shown an increase in resilient modulus for increment of carbon black and modulus of resilient for mixes with 9 percent carbon black was 1.4 times that for mixes with 0 percent carbon black. The altering of carbon black from a range (3-9 percent has modified the fatigue property of the asphalt concrete mixes as determined by flexural test, Significantly, to modify the asphalt concrete manner taken the  percent of carbon black 6, and to produce the mixes more durable , higher resistance to distresses by adding the local knowledge.

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  18. Example Annual Certification & Compliance Reports for Sources with and without Visible Emissions Testing: NESHAP Area Source Standards for Nine Metal Fabrication and Finishing Source Categories 40 CFR 63 Subpart XXXXXX

    Science.gov (United States)

    This page contains examples of the type of information that must be submitted to fulfill the Notification of Compliance Status requirement of 40 CFR 63, subpart XXXXXX for sources reporting and not reporting visible emissions information.

  19. Natural asphalt modified binders used for high stiffness modulus asphalt concrete

    Science.gov (United States)

    Bilski, Marcin; Słowik, Mieczysław

    2018-05-01

    This paper presents a set of test results supporting the possibility of replacing, in Polish climate conditions, hard road 20/30 penetration grade bitumen used in the binder course and/or base course made of high stiffness modulus asphalt concrete with binders comprising of 35/50 or 50/70 penetration grade bitumens and additives in the form of natural Gilsonite or Trinidad Epuré asphalts. For the purpose of comparing the properties of the discussed asphalt binders, values of the Performance Grade have been determined according to the American Superpave system criteria.

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

    Directory of Open Access Journals (Sweden)

    Feipeng Xiao

    2010-01-01

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

  1. Evaluation of rubber modified asphalt demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    As part of the Ontario Government's medium-term scrap tire management strategy, 11 rubber modified asphalt demonstration projects were funded or completed, with 13 additional projects from small to large (1,500-65,000 passenger tire equivalents) approved for the 1993 paving season. This report presents the results of an August to November 1993 study of the 11 demonstration projects. The evaluation included a description of the technology; technical review of the projects; economic analysis; review of the environmental literature; environmental review of the projects; comparison of the projects with similar ones in other jurisdictions; and recommendations. Detailed information on asphalt technology is included in an appendix.

  2. Hot Mix Asphalt Recycling: Practices and Principles

    OpenAIRE

    Mohajeri, M.

    2015-01-01

    Hot mix asphalt recycling has become common practice all over the world since the 1970s because of the crisis in oil prices. In the Netherlands, hot recycling has advanced to such an extent that in most of the mixtures more than 50% of reclaimed asphalt (RA) is allowed. These mixtures with such a high RA content are produced in a batch plant to which a parallel drum is attached. In this drum RA is pre-heated to approximately 130°C. Since 2007 another hot mix recycling techniques became availa...

  3. Practical experiences with new types of highly modified asphalt binders

    Science.gov (United States)

    Špaček, Petr; Hegr, Zdeněk; Beneš, Jan

    2017-09-01

    As a result of steadily increasing traffic load on the roads in the Czech Republic, we should be focused on the innovative technical solutions, which will lead to extending the life time of asphalt pavements. One of these ways could be the future use of bitumen with a higher degree of polymer modification. This paper discusses experience with comparison of new highly polymer modified asphalt binder type with conventional polymer modified asphalt binder and unmodified binder with penetration grade 50/70. There are compared the results of various types laboratory tests of asphalt binders, as well as the results of asphalt mixtures laboratory tests. The paper also mentions the experience with workability and compactability of asphalt mixture with highly polymer modified asphalt binder during the realization of the experimental reference road section by the Skanska company in the Czech Republic.

  4. Volumetric characteristics and compactability of asphalt rubber mixtures with organic warm mix asphalt additives

    Directory of Open Access Journals (Sweden)

    A. M. Rodríguez-Alloza

    2017-04-01

    Full Text Available Warm Mix Asphalt (WMA refers to technologies that reduce manufacturing and compaction temperatures of asphalt mixtures allowing lower energy consumption and reducing greenhouse gas emissions from asphalt plants. These benefits, combined with the effective reuse of a solid waste product, make asphalt rubber (AR mixtures with WMA additives an excellent environmentally-friendly material for road construction. The effect of WMA additives on rubberized mixtures has not yet been established in detail and the lower mixing/compaction temperatures of these mixtures may result in insufficient compaction. In this sense, the present study uses a series of laboratory tests to evaluate the volumetric characteristics and compactability of AR mixtures with organic additives when production/compaction temperatures are decreased. The results of this study indicate that the additives selected can decrease the mixing/compaction temperatures without compromising the volumetric characteristics and compactability.

  5. Investigation of the use of recycled polymer-modified asphalt in asphaltic concrete pavements.

    Science.gov (United States)

    2004-06-30

    This report presents issues associated with recycling polymer modified asphalt cements (PMACs), particularly blending aged PMAC with new PMAC. A styrene-butadiene-styrene (SBS) PMAC was selected and graded using the Superpave Performance Grading (PG)...

  6. Volumetric characteristics and compactability of asphalt rubber mixtures with organic warm mix asphalt additives

    International Nuclear Information System (INIS)

    Rodríguez-Alloza, A.M.; Gallego, J.

    2017-01-01

    Warm Mix Asphalt (WMA) refers to technologies that reduce manufacturing and compaction temperatures of asphalt mixtures allowing lower energy consumption and reducing greenhouse gas emissions from asphalt plants. These benefits, combined with the effective reuse of a solid waste product, make asphalt rubber (AR) mixtures with WMA additives an excellent environmentally-friendly material for road construction. The effect of WMA additives on rubberized mixtures has not yet been established in detail and the lower mixing/compaction temperatures of these mixtures may result in insufficient compaction. In this sense, the present study uses a series of laboratory tests to evaluate the volumetric characteristics and compactability of AR mixtures with organic additives when production/compaction temperatures are decreased. The results of this study indicate that the additives selected can decrease the mixing/compaction temperatures without compromising the volumetric characteristics and compactability. [es

  7. Steel Slag as an Aggregate Replacement in Malaysian Hot Mix Asphalt

    OpenAIRE

    Hainin, Mohd Rosli; Yusoff, Nur Izzi Md.; Mohammad Sabri, Mohd Fahmi; Abdul Aziz, Mohd Azizi; Sahul Hameed, Mohd Anwar; Farooq Reshi, Wasid

    2012-01-01

    As natural aggregate sources are becoming depleted due to high demand in road construction and the amount of disposed waste material keeps increasing, researchers are exploring the use of alternative materials which could preserve natural sources and save the environment. In this study, steel slag was used as an aggregate replacement in conventional dense graded asphalt mixes (ACW14 and ACB28). Steel slag was selected due to its characteristics, which are almost similar to conventional aggreg...

  8. Rheological characterization of asphalt binders used in strain relief asphalt mixtures (SRAM)

    OpenAIRE

    Vasconcelos, Kamilla L.; Bariani Bernucci, Liedi Legi; Midori Takahashi, Marcia; Castelo-Branco, Verônica T. F.

    2017-01-01

    Abstract The use of ´interlayers´ that tolerate high tensile and shear strain that exists above cracks in deteriorated pavements is becoming an interesting solution to prevent reflective cracking. Recent advances in polymer technology have led to binders that can be used to produce interlayer mixtures with good mechanical properties. In this study, two polymer-modified asphalt binders were evaluated, both from the production of strain relief asphalt mixtures used as interlayers in the field. ...

  9. Carbon fiber reinforced asphalt concrete

    International Nuclear Information System (INIS)

    Jahromi, Saeed G.

    2008-01-01

    Fibers are often used in the manufacture of other materials. For many years, they have been utilized extensively in numerous applications in civil engineering. Fiber-reinforcement refers to incorporating materials with desired properties within some other materials lacking those properties. Use of fibers is not a new phenomenon, as the technique of fiber-reinforced bitumen began early as 1950. In all industrialized countries today, nearly all concretes used in construction are reinforced. A multitude of fibers and fiber materials are being introduced in the market regularly. The present paper presents characteristics and properties of carbon fiber-reinforced asphalt mixtures, which improve the performance of pavements. To evaluate the effect of fiber contents on bituminous mixtures, laboratory investigations were carried out on the samples with and without fibers. During the course of this study, various tests were undertaken, applying Marshall Test indirect tensile test, creep test and resistance to fatigue cracking by using repeated load indirect tensile test. Carbon fiber exhibited consistency in results and as such it was observed that the addition of fiber does affect the properties of bituminous mixtures, i.e. an increase in its stability and decrease in the flow value as well as an increase in voids in the mix. Results indicate that fibers have the potential to resist structural distress in pavement, in the wake of growing traffic loads and thus improve fatigue by increasing resistance to cracks or permanent deformation. On the whole, the results show that the addition of carbon fiber will improve some of the mechanical properties like fatigue and deformation in the flexible pavement. (author)

  10. Toxicity of coal-tar and asphalt sealants to eastern newts, Notophthalmus viridescens

    Energy Technology Data Exchange (ETDEWEB)

    Bommarito, T.; Sparling, D.W.; Halbrook, R.S. [South Illinois University, Carbondale, IL (United States). Cooperative Wildlife Research Laboratory

    2010-09-15

    Between 1970 and 2000 the concentration of total polycyclic aromatic hydrocarbons (TPAH) in several lakes across the country increased whereas those of other persistent organic pollutants (POPs) tended to remain stable or declined. Urbanized watersheds experienced greater rises in TPAH concentration compared to non-urban lakes. Sources for urban PAHs include industrial wastes, vehicular exhausts and oil leaks and sealants from pavement surfaces. Both coal-tar and asphalt sealants are used to protect surfaces but runoff from surfaces coated with coal-tar can have mean concentrations of 3500 mg TPAHs kg{sup -1}, much higher than runoff from asphalt-sealed or cement surfaces. Unaltered parent compounds of PAHs can have many lethal and sublethal toxic effects, but oxidation and UV radiation can alter the toxicity of these compounds, sometimes creating degradates that are many times more toxic than parent compounds. The purposes of this study were to determine if coal-tar sealants can be toxic to adult eastern newts (Notophthalmus viridescens) and to compare the toxicity of coal-tar sealant to that of asphalt sealant. Newts were exposed to sediments containing dried sealants ranging from 0 mg kg{sup -1} to 1500 mg kg{sup -1} under simultaneous exposure to UV radiation and visible light to determine concentration/response relationships. No significant mortality occurred with any treatment. Significant effects due to sealants included decreased righting ability and diminished liver enzyme activities. Coal-tar sealant was more effective in inducing these changes than was asphalt sealant.

  11. Understanding asphalt compaction: An action research strategy

    NARCIS (Netherlands)

    Miller, Seirgei Rosario; ter Huerne, Henderikus L.; Doree, Andries G.; Amaratunga, Dilanthi

    2007-01-01

    In Hot Mix Asphalt (HMA) construction, rollers provide the compaction energy required to produce a specified density. However, little is known about the heuristics used by the roller operators. This study forms part of a larger action research project focussing on the improvement of the HMA paving

  12. Interfacial debonding of ice-asphalt concrete

    Energy Technology Data Exchange (ETDEWEB)

    Tazawa, E.; Mizoue, Y. (Hiroshima Univ., Hiroshima (Japan)); Kojima, T. (Hitachi Chemical Co. Ltd., Tokyo (Japan))

    1992-09-20

    Series of experimental investigations were carried out to clarify the bonding mechanism between ice and asphalt and to develop a new technique to reduce bonding resistance. The surface bonding resistance was measured by three methods and the main variables taken into consideration have been surface energy, surface roughness and stiffness of asphalt. Surface energy was varied by using various water repellents and the stiffness of the concrete was varied by mixing rubber particles. Correlations of the three variables were studied and the following results have been obtained. Decreasing of surface energy and increasing of deformability of asphalt concrete has been the effective method to decrease the bonding between ice and asphalt. For the case of water repellent coated surface, shear debonding strength has been linearly related to the energy required for debonding by dynamic tension and the shear debonding strength has decreased with the decrease in roughness of pavement. In the case of surface without using repellent, shear debonding strength has not been influenced by surface energy and roughness of pavement. 6 refs., 16 figs., 7 tabs.

  13. Extending the Lifespan of Porous Asphalt Concrete

    NARCIS (Netherlands)

    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

  14. Application of Conductive Materials to Asphalt Pavement

    Directory of Open Access Journals (Sweden)

    Hai Viet Vo

    2017-01-01

    Full Text Available Snow-melting pavement technique is an advanced preservation method, which can prevent the forming of snow or ice on the pavement surface by increasing the temperature using an embedded heating system. The main scope of this study is to evaluate the impact of conductive additives on the heating efficiency. The electrical resistivity and thermal conductivity were considered to investigate effects of conductive additives, graphite, and carbon fibers on the snow-melting ability of asphalt mixtures. Also, the distribution of the conductive additives within the asphalt concrete body was investigated by microstructural imaging. An actual test was applied to simulate realistic heating for an asphalt concrete mixture. Thermal testing indicated that graphite and carbon fibers improve the snow-melting ability of asphalt mixes and their combination is more effective than when used alone. As observed in the microstructural image, carbon fibers show a long-range connecting effect among graphite conductive clusters and gather in bundles when added excessively. According to the actual test, adding the conductive additives helps improve snow-melting efficiency by shortening processing time and raising the surface temperature.

  15. Steady-State Creep of Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Alibai Iskakbayev

    2017-02-01

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

  16. IDENTIFICATION AND CHARACTERIZATION OF FIVE NON- TRADITIONAL SOURCE CATEGORIES: CATASTROPHIC/ACCIDENTAL RELEASES, VEHICLE REPAIR FACILITIES, RECYCLING, PESTICIDE APPLICATION, AND AGRICULTURAL OPERATIONS

    Science.gov (United States)

    The report gives results of work that is part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to deve...

  17. Plastic Bottles Waste Utilization as Modifier for Asphalt Mixture Production

    Directory of Open Access Journals (Sweden)

    Jan Hakeem

    2017-01-01

    Full Text Available Plastic Bottles was used as the polymeric waste to investigate performance of asphalt mixture Aggregates obtained from Margalla, Burhan and Karak quarries. 12 samples were prepared for conventional asphalt mixtures and 48 samples were prepared for PB modified asphalt mixture of each quarries at various proportions of PB waste. The PB used for modification according to wet process are 15%, 20%, 25% and 30% by weight of Optimum Bitumen Content (OBC. OBC of 4.2 % was concluded for conventional asphalt mixtures. The stability and flow values of the conventional and modified Asphalt Mixture were compared. The average Stability of the modified Margalla asphalt mixtures when 15% PB was used was much higher as compared to conventional asphalt mixtures. But when PB was used beyond 15%, the Marshall stability showed a decreasing trend for Margalla aggregates, increasing trend for Karak aggregates and decreasing trend for Burhan aggregates. This decline in stability is attributed to a decline in interlocking of aggregates due to lubricating effect. The corresponding flow for the Modified asphalt mixtures first showed a decreasing trend for Margalla aggregates at 15% PB modification but beyond 15%, an increasing trend in flow as compared to conventional asphalt mixtures The decrease in flow or increase in Marshall Stability is attributed to improvement in interlocking and decline in flow or stability is attributed to a decline in interlocking offered by binder and PB coated aggregate particles in modified asphalt.

  18. Study of Antiultraviolet Asphalt Modifiers and Their Antiageing Effects

    Directory of Open Access Journals (Sweden)

    Jinxuan Hu

    2017-01-01

    Full Text Available Ultraviolet (UV radiation causes serious ageing problems on pavement surface. In recent years, different UV blocking materials have been used as modifiers to prevent asphalt ageing during the service life of the pavement. In this study, three different materials have been used as modifiers in base asphalt to test their UV blocking effects: layered double hydroxides (LDHs, organomontmorillonite (OMMT, and carbon black (CB. UV ageing was applied to simulate the ageing process and softening point, penetration, ductility, DSR (Dynamic Shear Rheometer test, and Fourier Transform Infrared Spectroscopy (FTIR test were conducted to evaluate the anti-UV ageing effects of the three UV blocking modifiers. Physical property tests show that base asphalt was influenced more seriously by UV radiation compared to the modified asphalt. DSR test results indicate that the complex modulus of asphalt before UV ageing is increased because of modifiers, while the complex modulus of base asphalt after UV ageing is higher than that of the modified asphalt, which shows that the UV blocking modifiers promote the antiageing effects of asphalt. FTIR test reveals that the increment of carbonyl groups and sulfoxide groups of modified asphalt is less than that in base asphalt. Tests indicate the best UV blocking effect results for samples with LDHs and the worst UV blocking effect results for samples with CB.

  19. Fundamental evaluation of the interaction between RAS/RAP and virgin asphalt binders.

    Science.gov (United States)

    2017-08-01

    A comprehensive laboratory testing program was conducted in this research project to examine the blending between reclaimed asphalt pavement (RAP)/recycled asphalt shingles (RAS) and virgin asphalt binders and to evaluate the factors that may affect ...

  20. Categories from scratch

    NARCIS (Netherlands)

    Poss, R.

    2014-01-01

    The concept of category from mathematics happens to be useful to computer programmers in many ways. Unfortunately, all "good" explanations of categories so far have been designed by mathematicians, or at least theoreticians with a strong background in mathematics, and this makes categories

  1. Thermal Properties of Asphalt Mixtures Modified with Conductive Fillers

    Directory of Open Access Journals (Sweden)

    Byong Chol Bai

    2015-01-01

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

  2. Rheo-mechanical model for self-healing asphalt pavement

    International Nuclear Information System (INIS)

    Gömze, A L; Gömze, L N

    2017-01-01

    Examining the rheological properties of different asphalt mixtures at different temperatures, pressures and deformation conditions on the combined rheo-tribometers the authors have found that the generally used Burgers-model doesn’t explain the deformation properties of asphalt mixtures and pavements under loading forces and loading pressures. To understand better the rheological and deformation properties of such complex materials like asphalt mixtures and pavements the authors used Malvern Mastersizer X laser granulometer, Bruker D8 Advance X-ray diffractometer, Hitachi TM 1000 Scanning Elektronmicroscope, Tristar 3000 specific surface tester and the combined rheo-tribometer developed and patented by the authors. After the complex investigation of different asphalt mixtures the authors have found a new, more complex rheological model for the asphalts including self-healing asphalt pavements. (paper)

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

    Directory of Open Access Journals (Sweden)

    Ludfi Djakfar

    2015-01-01

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

  4. Contributory Factors Related to Permanent Deformation of Hot Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Alaa Husein Abd

    2017-03-01

    Full Text Available Permanent deformation (Rutting of asphalt pavements which appears in many roads in Iraq, have caused a major impact on pavement performance by reducing the useful service life of pavement and creating services hazards for highway users. The main objective of this research is investigating the effect of some contributory factors related to permanent deformation of asphalt concrete mixture. To meet the objectives of this research, available local materials are used including asphalt binder, aggregates, mineral filler and modified asphalt binder. The Superpave mix design system was adopted with varying volumetric compositions. The Superpave Gyratory Compactor was used to compact 24 asphalt concrete cylindrical specimens. To collect the required data and investigate the development of permanent deformation in asphalt concrete under repeated loadings, Wheel-Tracking apparatus has been used in a factorial testing program during which 44 slab samples; with dimensions of 400×300×50 mm; were tested to simulate . actual pavement. Based on wheel-tracking test results, it has been concluded that increasing the compaction temperature from 110 to 150ºC caused a decreasing in permanent deformation by 20.5 and 15.6 percent for coarse and fine gradation control asphalt mixtures respectively. While the permanent deformation decreased about 21.3 percent when the compaction temperature is increased from 110 to 150ºC for coarse gradation asphalt mixtures modified with styrene butadiene styrene SBS with 3 percent by asphalt binder weight.

  5. Field testing of asphalt-emulsion radon-barrier system

    International Nuclear Information System (INIS)

    Hartley, J.N.; Freeman, H.D.; Baker, E.G.; Elmore, M.R.; Nelson, D.A.; Voss, C.F.; Koehmstedt, P.L.

    1981-09-01

    Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10 -6 cm 2 /s. The 1981 joint field test is a culmination of all the technology developed to date for asphalt emulsion radon barrier systems. Preliminary results of this field test and the results of the 1980 field test are presented. 18 figures, 6 tables

  6. Physical and rheological properties of Titanium Dioxide modified asphalt

    Science.gov (United States)

    Buhari, Rosnawati; Ezree Abdullah, Mohd; Khairul Ahmad, Mohd; Chong, Ai Ling; Haini, Rosli; Khatijah Abu Bakar, Siti

    2018-03-01

    Titanium Dioxide (TiO2) has been known as a useful photocatalytic material that is attributed to the several characteristics includes high photocatalytic activity compared with other metal oxide photocatalysts, compatible with traditional construction materials without changing any original performance. This study investigates the physical and rheological properties of modified asphalt with TiO2. Five samples of asphalt with different concentration of TiO2 were studied, namely asphalt 2%, 4%, 6% 8% and 10% TiO2. The tests includes are penetration, softening point, ductility, rotational viscosity and dynamic shear rheometer (DSR) test. From the results of this study, it is noted that addition of TiO2 has significant effect on the physical properties of asphalt. The viscosity tests revealed that asphalt 10% TiO2 has good workability among with reducing approximately 15°C compared to base asphalt. Based on the results from DSR measurements, asphalt 10% TiO2 has reduced temperature susceptibility and increase stiffness and elastic behaviour in comparison to base asphalt. As a result, TiO2 can be considered to be an additive to modify the properties of asphalt.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  8. Characteristics Buton Natural Asphalt-Rubber (BNA-R on the Performance Improvement of Warm Mix Asphalt Using Natural Zeolite

    Directory of Open Access Journals (Sweden)

    Wahjuningsih Nurul

    2018-01-01

    Full Text Available The decrease in the ability of service of pavement can be caused by the durability factor in the pavement layer in receiving heavy traffic load and the temperature of the pavement. Permanent deformation is one of the criteria of failure of asphalt mixture. Performance assessment of the asphalt mixture can be observed from the rheological properties of asphalt binder. The use of BNA-R in this study is intended to modify the characteristics of bitumen penetration grade 60 / 70 used in warm mix asphalt. Warm mix asphalt with lower temperatures of mixing and compaction than conventional asphalt mixtures was chosen because it is more environmentally friendly. To reduce the temperature in this warm asphalt technology is achieved by using natural zeolite. Both of these materials are local materials that are widely available in Indonesia. The rheology of asphalt 60/70 modified with BNA-R indicates that the addition of BNA-R in the base asphalt increase the complex modulus value and decrease the phase angle value. These values were related to the performance of mixture in the permanent deformation criteria. Reducing the temperature of mixing and compaction should be balanced with modifying the asphalt binder used. Rutting due to permanent deformation can resulted in inconvenience to the passengers and can lead to high costs of road maintenance. To determine the permanent deformation of asphalt mix with material combinations was performed through the wheel tracking test machine with 3,780 cycles for 3 hours. The results shows that after test track over 7 thousand passes have seen permanent deformation characteristics of asphalt concrete mixture with a variation of the characteristics of bitumen.

  9. Characteristics Buton Natural Asphalt-Rubber (BNA-R) on the Performance Improvement of Warm Mix Asphalt Using Natural Zeolite

    Science.gov (United States)

    Wahjuningsih, Nurul; Pranowo Hadiwardoyo, Sigit; Jachrizal Sumabrata, R.

    2018-03-01

    The decrease in the ability of service of pavement can be caused by the durability factor in the pavement layer in receiving heavy traffic load and the temperature of the pavement. Permanent deformation is one of the criteria of failure of asphalt mixture. Performance assessment of the asphalt mixture can be observed from the rheological properties of asphalt binder. The use of BNA-R in this study is intended to modify the characteristics of bitumen penetration grade 60 / 70 used in warm mix asphalt. Warm mix asphalt with lower temperatures of mixing and compaction than conventional asphalt mixtures was chosen because it is more environmentally friendly. To reduce the temperature in this warm asphalt technology is achieved by using natural zeolite. Both of these materials are local materials that are widely available in Indonesia. The rheology of asphalt 60/70 modified with BNA-R indicates that the addition of BNA-R in the base asphalt increase the complex modulus value and decrease the phase angle value. These values were related to the performance of mixture in the permanent deformation criteria. Reducing the temperature of mixing and compaction should be balanced with modifying the asphalt binder used. Rutting due to permanent deformation can resulted in inconvenience to the passengers and can lead to high costs of road maintenance. To determine the permanent deformation of asphalt mix with material combinations was performed through the wheel tracking test machine with 3,780 cycles for 3 hours. The results shows that after test track over 7 thousand passes have seen permanent deformation characteristics of asphalt concrete mixture with a variation of the characteristics of bitumen.

  10. Optical microtopographic inspection of asphalt pavement surfaces

    Science.gov (United States)

    Costa, Manuel F. M.; Freitas, E. F.; Torres, H.; Cerezo, V.

    2017-08-01

    Microtopographic and rugometric characterization of surfaces is routinely and effectively performed non-invasively by a number of different optical methods. Rough surfaces are also inspected using optical profilometers and microtopographer. The characterization of road asphalt pavement surfaces produced in different ways and compositions is fundamental for economical and safety reasons. Having complex structures, including topographically with different ranges of form error and roughness, the inspection of asphalt pavement surfaces is difficult to perform non-invasively. In this communication we will report on the optical non-contact rugometric characterization of the surface of different types of road pavements performed at the Microtopography Laboratory of the Physics Department of the University of Minho.

  11. Finite element simulation of asphalt fatigue testing

    DEFF Research Database (Denmark)

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

    1997-01-01

    The traditional interpretation of fatigue tests on asphalt mixes has been in terms of a logarithmic linear relationship between the constant stress or strain amplitude and the number of load repetitions to cause failure, often defined as a decrease in modulus to half the initial value...... damage mechanics.The paper describes how continuum damage mechanics may be used with a finite element program to explain the progressive deterioration of asphalt mixes under laboratory fatigue testing. Both constant stress and constant strain testing are simulated, and compared to the actual results from...... three point and four point fatigue test on different mixes. It is shown that the same damage law, based on energy density, may be used to explain the gradual deterioration under constant stress as well as under constant strain testing.Some of the advantages of using this method for interpreting fatigue...

  12. Ageing evolution of foamed warm mix asphalt combined with reclaimed asphalt pavement

    International Nuclear Information System (INIS)

    Perez-Martinez, M.; Marsac, P.; Gabet, T.; Pouget, S.; Hammoum, F.

    2017-01-01

    The combination of high rates of reclaimed asphalt pavement (RAP) and warm mix asphalt (WMA) technologies is still ambiguous in terms of durability. With the aim of clarifying this issue, a study comparing a hot mix asphalt with a WMA prepared using the foaming process technology. Both mixes contain 50% of RAP and are submitted to a laboratory ageing procedure. The long term related performance of the mixtures is compared by means of complex modulus and fatigue testing. Penetration and ring and ball tests are undertaken on the recovered bitumens, as well as the ageing evolution, characterised by the Fourier Transform Infrared analysis. Finally, the Apparent Molecular Weight Distribution (AMWD) of the binders is calculated from rheological measurements using the δ-method. Results show a relation between ageing evolution and mechanical performance. After ageing, the overall tendencies are similar for both processes. [es

  13. Present status and future of various rubber materials. ; Asphalt. Kakushu gomu zairyo no genjo to kongo. ; Asphalt

    Energy Technology Data Exchange (ETDEWEB)

    Wakisaka, S. (Toa Doro Kogyo Co. Ltd., Tokyo (Japan))

    1991-12-15

    Asphalt is obtained at a rate of about 25 Kg per 1 Kl of oil and is produced at about 5 million tons per annum in Japan, 80 % of which is now used for the pavement of road. The purpose of this study is to examine the possibilities of developing new applications of asphalt to the anti-vibration, vibration-control and anti-noise materials, though its uses have already been diversified in fields other than for road paving, due to excellent performance regardless of cheap cost. In the paper, firstly, under a title of what is asphalt, the history, the composition and internal structure of asphalt were considered. Secondly, the dynamic characteristics of asphalt were considered. And lastly, under a title of the application of asphalt, examples of the application of asphalt to anti-noise materials were examined in the field of architecture, automobile and civil engineering respectively. Especially, in the field of civil engineering, improvements of flexibility and vibration-control by using the cement asphalt mortar (CAM) in the anti-vibration A-type slab track for railway, and also anti-noise and anti-vibration technologies applied to the road pavement body by using the ferrite asphalt were reviewed. 11 refs., 10 figs., 8 tabs.

  14. Blocking in Category Learning

    OpenAIRE

    Bott, Lewis; Hoffman, Aaron B.; Murphy, Gregory L.

    2007-01-01

    Many theories of category learning assume that learning is driven by a need to minimize classification error. When there is no classification error, therefore, learning of individual features should be negligible. We tested this hypothesis by conducting three category learning experiments adapted from an associative learning blocking paradigm. Contrary to an error-driven account of learning, participants learned a wide range of information when they learned about categories, and blocking effe...

  15. Category I structures program

    International Nuclear Information System (INIS)

    Endebrock, E.G.; Dove, R.C.

    1981-01-01

    The objective of the Category I Structure Program is to supply experimental and analytical information needed to assess the structural capacity of Category I structures (excluding the reactor cntainment building). Because the shear wall is a principal element of a Category I structure, and because relatively little experimental information is available on the shear walls, it was selected as the test element for the experimental program. The large load capacities of shear walls in Category I structures dictates that the experimental tests be conducted on small size shear wall structures that incorporates the general construction details and characteristics of as-built shear walls

  16. Dynamic modulus of nanosilica modified porous asphalt

    Science.gov (United States)

    Arshad, A. K.; Masri, K. A.; Ahmad, J.; Samsudin, M. S.

    2017-11-01

    Porous asphalt (PA) is a flexible pavement layer with high interconnected air void contents and constructed using open-graded aggregates. Due to high temperature environment and increased traffic volume in Malaysia, PA may have deficiencies particularly in rutting and stiffness of the mix. A possible way to improve these deficiencies is to improve the asphalt binder used. Binder is normally modified using polymer materials to improve its properties. However, nanotechnology presently is being gradually used for asphalt modification. Nanosilica (NS), a byproduct of rice husk and palm oil fuel ash is used as additive in this study. The aim of this study is to enhance the rutting resistance and stiffness performance of PA using NS. This study focused on the performance of PA in terms of dynamic modulus with the addition of NS modified binder to produce better and more durable PA. From the result of Dynamic SPT Test, it shows that the addition of NS was capable in enhancing the stiffness and rutting resistance of PA. The addition of NS also increase the dynamic modulus value of PA by 50%.

  17. Active carbon production from modified asphalt

    International Nuclear Information System (INIS)

    Fadhi, A.B.

    2006-01-01

    A granular activated carbons (GACs) have been prepared from some local raw materials such as Qiayarah asphalt (QA) after some modification treatments of this asphalt by various ratios of its original constituents (asphaltenes and maltens) at 180 degree C. Thermal carbonization method by sulfur and steam physical activation have been used for AC preparation. The carbons thus prepared were characterized in the term of iodine, methylene blue (MB), P-nitro phenol (PNP) and CCl4 adsorption. The BET surface area of the prepared ACs has been estimated via a calibration curve between iodine numbers and surface area determined from N2 adsorption isotherm from previous studies, also, the surface area of the prepared ACs were determined through another methods such as retention method by ethylene glycol mono ethyl ether (EGME), adsorption from vapor phase using acetone vapor and adsorption from solution method using PNP and MB as solutes. The results referred to the success of modification method for preparing ACs of good micro porosity as compared with the AC from the untreated asphalt as well as the commercial sample. (author)

  18. Rapid Radiochemical Methods for Asphalt Paving Material ...

    Science.gov (United States)

    Technical Brief Validated rapid radiochemical methods for alpha and beta emitters in solid matrices that are commonly encountered in urban environments were previously unavailable for public use by responding laboratories. A lack of tested rapid methods would delay the quick determination of contamination levels and the assessment of acceptable site-specific exposure levels. Of special concern are matrices with rough and porous surfaces, which allow the movement of radioactive material deep into the building material making it difficult to detect. This research focuses on methods that address preparation, radiochemical separation, and analysis of asphalt paving materials and asphalt roofing shingles. These matrices, common to outdoor environments, challenge the capability and capacity of very experienced radiochemistry laboratories. Generally, routine sample preparation and dissolution techniques produce liquid samples (representative of the original sample material) that can be processed using available radiochemical methods. The asphalt materials are especially difficult because they do not readily lend themselves to these routine sample preparation and dissolution techniques. The HSRP and ORIA coordinate radiological reference laboratory priorities and activities in conjunction with HSRP’s Partner Process. As part of the collaboration, the HSRP worked with ORIA to publish rapid radioanalytical methods for selected radionuclides in building material matrice

  19. Categories and logical syntax

    NARCIS (Netherlands)

    Klev, Ansten Morch

    2014-01-01

    The notions of category and type are here studied through the lens of logical syntax: Aristotle's as well as Kant's categories through the traditional form of proposition `S is P', and modern doctrines of type through the Fregean form of proposition `F(a)', function applied to argument. Topics

  20. Computing color categories

    NARCIS (Netherlands)

    Yendrikhovskij, S.N.; Rogowitz, B.E.; Pappas, T.N.

    2000-01-01

    This paper is an attempt to develop a coherent framework for understanding, modeling, and computing color categories. The main assumption is that the structure of color category systems originates from the statistical structure of the perceived color environment. This environment can be modeled as

  1. Asphalt features and gas accumulation mechanism of Sinian reservoirs in the Tongwan Palaeo-uplift, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Wei Li

    2015-10-01

    Full Text Available Breakthroughs have been made in natural gas exploration in Sinian reservoirs in the Tongwan Palaeo-uplift, Sichuan Basin, recently. However, there are disputes with regard to the genetic mechanisms of natural gas reservoirs. The development law of asphalts in the Sinian reservoirs may play an extremely important role in the study of the relationships between palaeo oil and gas reservoirs. Accordingly, researches were conducted on the features and development patterns of asphalts in the Sinian reservoirs in this area. The following research results were obtained. (1 Asphalts in the Sinian reservoirs were developed after the important hydrothermal event in the Sichuan Basin, namely the well-known Emei Taphrogeny in the mid-late Permian Period. (2 Distribution of asphalts is related to palaeo oil reservoirs under the control of palaeo-structures of Indosinian-Yanshanian Period, when the palaeo-structures contained high content of asphalts in the high positions of the palaeo-uplift. (3 Large-scale oil and gas accumulations in the Sinian reservoirs occurred in the Indosinian-Yanshanian Period to generate the Leshan-Ziyang and Gaoshiti-Moxi-Guang'an palaeo oil reservoirs. Cracking of crude oil in the major parts of these palaeo oil reservoirs controlled the development of the present natural gas reservoirs. (4 The development of asphalts in the Sinian reservoirs indicates that hydrocarbons in the Dengying Formation originated from Cambrian source rocks and natural gas accumulated in the Sinian reservoirs are products of late-stage cracking of the Sinian reservoirs. (5 The Sinian palaeo-structures of Indosinian-Yanshanian Period in the Sichuan Basin are favorable regions for the development of the Sinian reservoirs, where discoveries and exploration practices will play an important role in the era of Sinian natural gas development in China.

  2. 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

  3. 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

  4. Estimation of fatigue characteristics of asphaltic mixes using simple tests

    NARCIS (Netherlands)

    Medani, T.O.; Molenaar, A.A.A.

    2000-01-01

    A simplified procedure for estimation of fatigue characteristics of asphaltic mixes is presented. The procedure requires the determination of the so-called master curve (Le. the relationship between the mix stiffness, the loading time and the temperature), the asphalt properties and the mix

  5. 7 CFR 2902.36 - Concrete and asphalt release fluids.

    Science.gov (United States)

    2010-01-01

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

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

    NARCIS (Netherlands)

    Bijleveld, Frank; Doree, Andries G.; Kim,

    2014-01-01

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

  7. Application of waste tires to asphalt pavement. Improvement of adhesion of asphalt with rubber particles; Haitaiya no asphalt hoso eno tekiyo. Asphalt to gomu ryushi no fuchakusei no kairyo ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Nakaoka, I. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1994-10-10

    With an objective to apply waste tires to asphalt pavement, an experiment was carried out to improve adhesion of asphalt with rubber particles by using polymers. The state of interface on rubber particle and asphalt mixture was observed by a scanning electron microscope. As a result, it was found that the surface of untreated rubber particles is not bonded with the asphalt, but polymer treated mixture was found to have the affinity of rubber particles with asphalt improved. Tensile bonding strength was tested on rubber plates and asphalt. The result revealed that the polymer-reformed mixture has two times as large tensile bonding strength as that of the untreated mixture. With regard to the characters of asphalt mixture mixed with rubber particles, the stability shows a decreasing trend as compared with the standard asphalt concrete, but presents an excellent performance in wear. The fluidity resistance value is inferior to the standard, but not as great as presenting a problem under normal using environment, where its applicability as a road paving material was verified. 4 figs., 2 tabs.

  8. Hanford Permanent Isolation Barrier Program: Asphalt technology development

    International Nuclear Information System (INIS)

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

    1994-11-01

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

  9. Regional implementation of warm mix asphalt : [tech summary].

    Science.gov (United States)

    2014-09-01

    Asphalt is used in over 94 percent of all paved roadways in the United States. The ability to reduce its cost and : emissions while improving its performance has bene ts that could potentially change the direction the asphalt : industry moves in t...

  10. Induction healing of asphalt mixes with steel slag

    NARCIS (Netherlands)

    Apostolidis, P.; Liu, X.; Wang, H.; van de Ven, M.F.C.; Scarpas, Athanasios

    2018-01-01

    Asphaltic mixes are self-healing materials since they have the capacity to close internal microcracks at higher temperatures or under external force. To trigger their self-healing, asphalt mixes modified with inductive agents can be heated and in that way healed through applying alternating magnetic

  11. Advanced Experimental Evaluation of Asphalt Mortar for Induction Healing Purposes

    NARCIS (Netherlands)

    Apostolidis, P.; Liu, X.; Scarpas, Athanasios; van Bochove, G; van de Ven, M.F.C.

    2016-01-01

    This paper studied the induction heating and healing capacity of asphalt mortar by adding electrically conductive additives (e.g. iron powder and steel fibers), and examined the influence of different combinations of them on the mechanical response of asphalt mortars. Induction heating technique is

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

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Julide Oner

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

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

    Science.gov (United States)

    Oner, Julide; Sengoz, Burak

    2015-01-01

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

  15. 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.

  16. Triangulated categories (AM-148)

    CERN Document Server

    Neeman, Amnon

    2014-01-01

    The first two chapters of this book offer a modern, self-contained exposition of the elementary theory of triangulated categories and their quotients. The simple, elegant presentation of these known results makes these chapters eminently suitable as a text for graduate students. The remainder of the book is devoted to new research, providing, among other material, some remarkable improvements on Brown''s classical representability theorem. In addition, the author introduces a class of triangulated categories""--the ""well generated triangulated categories""--and studies their properties. This

  17. Performance evaluation of stone matrix asphalt using indonesian natural rock asphalt as stabilizer

    Directory of Open Access Journals (Sweden)

    Nyoman Suaryana

    2016-09-01

    Full Text Available One type of road pavement material which is developed to be more resistant to permanent deformation is the SMA (Stone Matrix Asphalt. Utilization of the SMA mix in Indonesia has constraints in gain stabilizer and also difficulty to comply the gradations, mainly because it needs a relatively large amount of filler. Alternative of local materials that can be used is asbuton (natural rock asphalt from Buton Island. Asbuton is expected to act as a stabilizer and simultaneously provides an additional filler. The objective of this research is to evaluate the performance of the SMA that uses the asbuton. The methodology used in this research is the experimental method, its starts from material testing, design mix and performance testing that includes dynamic modulus, permanent deformation and fatigue resistance. The results obtained showed asbuton can prevent asphalt draindown as well as increase the proportion of filler. Draindown asphalt can be prevented by using binder absorbers with fiber cellulose and viscosity boosters with asbuton. Asbuton (LGA 50/25 can behave as a stabilizer as well as cellulose fiber. Addition of asbuton also improves the performance of the SMA mix, as shown with increase in the value of dynamic stability. In terms of resistance to fatigue, SMA with cellulosa as stabilizer and SMA with asbuton as stabilizer, relatively have the same performance. Master curve of dynamic modulus indicates SMA with asbuton as stabilizer is relatively stiffer at high temperatures (more than 4.4 °C, but relatively less stiff (less brittle at low temperatures. Keywords: Stone matrix asphalt, Asbuton, Draindown, Dynamic modulus, Permanent deformation

  18. Analysis of rare categories

    CERN Document Server

    He, Jingrui

    2012-01-01

    This book focuses on rare category analysis where the majority classes have smooth distributions and the minority classes exhibit the compactness property. It focuses on challenging cases where the support regions of the majority and minority classes overlap.

  19. Consumer Product Category Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Chemical and Product Categories database (CPCat) catalogs the use of over 40,000 chemicals and their presence in different consumer products. The chemical use...

  20. Product Category Management Issues

    OpenAIRE

    Żukowska, Joanna

    2011-01-01

    The purpose of the paper is to present the issues related to category management. It includes the overview of category management definitions and the correct process of exercising it. Moreover, attention is paid to the advantages of brand management, the benefits the supplier and retailer may obtain in this way. The risk element related to this topics is also presented herein. Joanna Żukowska

  1. Performance of asphalt mixture incorporating recycled waste

    Science.gov (United States)

    Hamid, Nor Baizura; Abdullah, Mohd Ezree; Sanik, Mohd Erwan; Mokhtar, Mardiha; Kaamin, Masiri; Raduan, Rasyidah; Ramli, Mohd Zakwan

    2017-12-01

    Nowadays, the amount of premix waste was increased every year, especially at the batching plants. Normally, the waste materials will be discarded without doing any innovative and effective research about those materials. This situation has become one of the global concerns due to the increasing number of premix waste produced every year. Therefore, the aim of this study is to evaluate the performance of hot mix asphalt (HMA) using premix waste on improving asphalt mixture fatigue behaviour. The method used in this study was Superpave mix design method. The sample conducted in this study were 0%, 10%, 20%, 30%, and 100% of premix waste respectively. For a binder test, the laboratory test conducted were penetration test, softening test and thin film oven test while for the performance test were resilient modulus test and indirect tensile fatigue test. From the laboratory test, the resilient modulus test was conducted with two different temperature which was 25°C and 40°C. The result from that test was 20% of premix waste had higher resilient modulus at that two different temperatures compared to another samples. From that test also shown that the sample at the lower temperature which was 25°C has higher resilient modulus compared to the temperature of 40°C. Indirect tensile fatigue test showed that the 30% of premix waste sample was suitable for the modified asphalt mixture with referring to the maximum deformation and strain for comparison control, 10%,20%, and 100% of premix waste samples. So, it can be concluded that premix waste inhibits great potential as road construction material and suitable for repeated traffic loading.

  2. Characterisation of Asphalt Concrete Using Nanoindentation.

    Science.gov (United States)

    Barbhuiya, Salim; Caracciolo, Benjamin

    2017-07-18

    In this study, nanoindentation was conducted to extract the load-displacement behaviour and the nanomechanical properties of asphalt concrete across the mastic, matrix, and aggregate phases. Further, the performance of hydrated lime as an additive was assessed across the three phases. The hydrated lime containing samples have greater resistance to deformation in the mastic and matrix phases, in particular, the mastic. There is strong evidence suggesting that hydrated lime has the most potent effect on the mastic phase, with significant increase in hardness and stiffness.

  3. Use of emulsion for warm mix asphalt

    Directory of Open Access Journals (Sweden)

    Mahabir Panda

    2017-06-01

    Full Text Available Due to increase in energy costs and emission problems in hot mix asphalt usually used, it brought a great interest to the researchers to develop the warm mix technology for pavement constructions. Commonly known as warm mix asphalt (WMA, it is a typical method in the bituminous paving technology, which allows production and placement of bituminous mixes at lower temperatures than that used for hot mix asphalt (HMA. The WMA involves an environmental friendly production process that utilises organic additives, chemical additives and water based technologies. The organic and chemical additives are normally very costly and still involve certain amount of environmental issues. These factors motivated the authors to take up this technology using simple, environment friendly and somewhat cost effective procedure. In this study, an attempt has been made to prepare warm mixes by first pre-coating the aggregates with medium setting bitumen emulsion (MS and then mixing the semi-coated aggregates with VG 30 bitumen at a lower temperature than normally required. After a number of trials it was observed that mostly three mixing temperatures, namely temperatures 110 °C, 120 °C and 130 °C were appropriate to form the bituminous mixes with satisfactory homogeneity and consistency and as such were maintained throughout this study. Marshall samples for paving mixes were prepared using this procedure for dense bituminous macadam (DBM gradings as per the specifications of Ministry of Road Transport and Highways (MORTH and subsequently Marshall properties of the resultant mixes were studied with the main objective of deciding the different parameters that were considered for development of appropriate warm mix asphalt. In this study it has been observed that out of three mixing temperatures tried, the mixes prepared at 120 °C with bitumen-emulsion composition of 80B:20E for DBM warm mix, offer highest Marshall stability and highest indirect tensile strength

  4. Investigation of Properties of Asphalt Concrete Containing Boron Waste as Mineral Filler

    Directory of Open Access Journals (Sweden)

    Cahit GÜRER

    2016-05-01

    Full Text Available During the manufacture of compounds in the boron mining industry a large quantity of waste boron is produced which has detrimental effects on the environment. Large areas have to be allocated for the disposal of this waste. Today with an increase in infrastructure construction, more efficient use of the existing sources of raw materials has become an obligation and this involves the recycling of various waste materials. Road construction requires a significant amount of raw materials and it is possible that substantial amounts of boron-containing waste materials can be recycled in these applications. This study investigates the usability of boron wastes as filler in asphalt concrete. For this purpose, asphalt concrete samples were produced using mineral fillers containing 4%, 5%, 6%, 7% and 8% boron waste as well as a 6% limestone filler (6%L as the control sample. The Marshall Design, mechanical immersion and Marshall Stability test after a freeze-thaw cycle and indirect tensile stiffness modulus (ITSM test were performed for each of the series. The results of this experimental study showed that boron waste can be used in medium and low trafficked asphalt concrete pavements wearing courses as filler.

  5. Study on Method of Asphalt Density Measurement Using Low Level Radioactive Isotope

    International Nuclear Information System (INIS)

    Chung, Jin-young; Kim, Jung-hoon; Whang, Joo-ho

    2008-01-01

    The fundamental cause of damage to road pavement is insufficient management of asphalt density during construction. Currently, asphalt density in Korea is measured in a laboratory by extracting a core sample after construction. This method delays the overall time of measurement and therefore it is difficult to achieve real-time density management. Using a radioactive isotope for measuring asphalt density during construction reduces measuring time thus enabling realtime measurement. Also, it is provided reliable density measurement to achieve effective density management at work sites. However, existing radiological equipment has not been widely used because of management restrictions and regulations due to the high radiation dose. In this study, we employed a non-destructive method for density measurement. Density is measured by using a portable gamma-ray backscatter device having a radioactivity emission of 100 μCi or less (notice No. 2002-23, Ministry of Science and Technology, standards on radiation protection, etc.), a sealed radioactive source subject to declaration

  6. Performance Modification of Asphalt Binders using Thermoplastic Polymers

    Directory of Open Access Journals (Sweden)

    H. I. Al-Abdul Wahhab

    2004-12-01

    Full Text Available There is a need to improve the performance of asphalt binders to minimize stress cracking that occurs at low temperatures and plastic deformation at high temperatures. Importation of used asphalt-polymers from abroad, leads to an increase in the total construction cost as compared to the cost if the used polymers were of local origin. The main objective of this research was to modify locally produced asphalt. Ten polymers were identified as potential asphalt modifiers based on their physical properties and chemical composition. After preliminary laboratory evaluation for the melting point of these polymers, five polymers were selected for local asphalt modification. In the initial stage, required mixing time was decided based on the relation between shear loss modulus and mixing time .The optimum polymer content was selected based on Superpave binder performance grade specifications.The suitability of improvement was verified through the evaluation of permanent deformation and fatigue behavior of laboratory prepared asphalt concrete mixes. The results indicated that the rheological properties of the modified binders improved significantly with sufficient polymer content (3%. The aging properties of the modified binders were found to be dependent on the type of polymer.The fatigue life and resistance to permanent deformation were significantly improved due to enhanced binder rheological properties.  Thus, local asphalts can be modified using thermoplastic polymers.

  7. Qualitative criteria and thresholds for low noise asphalt mixture design

    Science.gov (United States)

    Vaitkus, A.; Andriejauskas, T.; Gražulytė, J.; Šernas, O.; Vorobjovas, V.; Kleizienė, R.

    2018-05-01

    Low noise asphalt pavements are cost efficient and cost effective alternative for road traffic noise mitigation comparing with noise barriers, façade insulation and other known noise mitigation measures. However, design of low noise asphalt mixtures strongly depends on climate and traffic peculiarities of different regions. Severe climate regions face problems related with short durability of low noise asphalt mixtures in terms of considerable negative impact of harsh climate conditions (frost-thaw, large temperature fluctuations, hydrological behaviour, etc.) and traffic (traffic loads, traffic volumes, studded tyres, etc.). Thus there is a need to find balance between mechanical and acoustical durability as well as to ensure adequate pavement skid resistance for road safety purposes. Paper presents analysis of the qualitative criteria and design parameters thresholds of low noise asphalt mixtures. Different asphalt mixture composition materials (grading, aggregate, binder, additives, etc.) and relevant asphalt layer properties (air void content, texture, evenness, degree of compaction, etc.) were investigated and assessed according their suitability for durable and effective low noise pavements. Paper concluded with the overview of requirements, qualitative criteria and thresholds for low noise asphalt mixture design for severe climate regions.

  8. Evaluation of warm mix technologies for use in asphalt rubber - asphaltic concrete friction courses (AR\\0x2010ACFC) : final report.

    Science.gov (United States)

    2016-07-01

    The objective of this research project was to determine whether warm mix asphalt (WMA) technologies can be : used by the Arizona Department of Transportation (ADOT) for the production of an asphalt rubberasphaltic : concrete friction course (AR...

  9. Nanoscale study on water damage for different warm mix asphalt binders

    Directory of Open Access Journals (Sweden)

    Kefei Liu

    2016-11-01

    Full Text Available In order to analyze the water damage to different warm mix asphalt binders from the micro scale, five kinds of asphalt binders, 70#A base asphalt, sasobit warm mix asphalt, energy champion 120 °C (EC120 warm mix asphalt, aspha-min warm mix asphalt, sulfur-extended asphalt modifier (SEAM warm mix asphalt, under different conditions (dry/wet, original/aging are prepared for laboratory tests. The atomic force microscope (AFM is used to observe the surface properties and measure the adhesion force between the asphalt and the mineral aggregate. The obtained results show that under the dry condition aspha-min warm mix asphalt and SEAM warm mix asphalt show stronger adhesive ability with the mineral aggregate compared with other asphalt binders, but also have relatively large dispersion and fluctuation in the tested results; under the wet condition, aspha-min warm mix asphalt and SEAM warm mix asphalt show stronger water damage resistance ability. The EC120 warm mix asphalt and aspha-min warm mix asphalt are less sensitive to moist, and their corresponding adhesion force is less susceptible to the change of external moisture conditions, leading to a better ability to resist water erosion. The aging process significantly lowers the moisture erosion resistance ability, which further impairs the water damage resistance ability. The base asphalt is more sensitive to moisture and more vulnerable to water damage, no matter whether it is under original or aging conditions. The aging aspha-min warm mix asphalt has the least loss of adhesion force, the smallest dispersion of the tested adhesion force, the strongest water damage resistance ability, no matter it is dry or wet. Keywords: Road engineering, Warm mix asphalt, Moisture damage, Atomic force microscope, Microcosmic

  10. Response to Question Concerning whether the Requirements for Preconstruction Review of New or Modified Air Pollution Sources Apply to the Relocation of an Existing Asphalt Concrete Plant when such Relocation does not Result in any Increase in Emissions

    Science.gov (United States)

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  11. Models as Relational Categories

    Science.gov (United States)

    Kokkonen, Tommi

    2017-11-01

    Model-based learning (MBL) has an established position within science education. It has been found to enhance conceptual understanding and provide a way for engaging students in authentic scientific activity. Despite ample research, few studies have examined the cognitive processes regarding learning scientific concepts within MBL. On the other hand, recent research within cognitive science has examined the learning of so-called relational categories. Relational categories are categories whose membership is determined on the basis of the common relational structure. In this theoretical paper, I argue that viewing models as relational categories provides a well-motivated cognitive basis for MBL. I discuss the different roles of models and modeling within MBL (using ready-made models, constructive modeling, and generative modeling) and discern the related cognitive aspects brought forward by the reinterpretation of models as relational categories. I will argue that relational knowledge is vital in learning novel models and in the transfer of learning. Moreover, relational knowledge underlies the coherent, hierarchical knowledge of experts. Lastly, I will examine how the format of external representations may affect the learning of models and the relevant relations. The nature of the learning mechanisms underlying students' mental representations of models is an interesting open question to be examined. Furthermore, the ways in which the expert-like knowledge develops and how to best support it is in need of more research. The discussion and conceptualization of models as relational categories allows discerning students' mental representations of models in terms of evolving relational structures in greater detail than previously done.

  12. Categories of transactions

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This chapter discusses the types of wholesale sales made by utilities. The Federal Energy Regulatory Commission (FERC), which regulates inter-utility sales, divides these sales into two broad categories: requirements and coordination. A variety of wholesale sales do not fall neatly into either category. For example, power purchased to replace the Three Mile Island outage is in a sense a reliability purchase, since it is bought on a long-term firm basis to meet basic load requirements. However, it does not fit the traditional model of a sale considered as part of each utility's long range planning. In addition, this chapter discusses transmission services, with a particular emphasis on wheeling

  13. Feasible integration in asphalt of piezoelectric cymbals for vibration energy harvesting

    International Nuclear Information System (INIS)

    Moure, A.; Izquierdo Rodríguez, M.A.; Rueda, S. Hernández; Gonzalo, A.; Rubio-Marcos, F.; Cuadros, D. Urquiza; Pérez-Lepe, A.; Fernández, J.F.

    2016-01-01

    Graphical abstract: A system based on piezoelectric cymbals embedded in asphalt for the first time is used as harvester for wasted vibrational energy produced by traffic. Energy density in the range of other alternative sources is achieved, with an estimated projected cost that shows the feasibility of this harvesting energy system. - Highlights: • Piezoelectric cymbals have been directly integrated in asphalt for the first time. • Harvesting from wasted vibrational energy caused by vehicles is demonstrated to be feasible by this integration. • Energy density and cost are estimated to be competitive with other sources as photovoltaic. • A 10% of the energy generated in the Region of Madrid can be obtained by covering only the 0.6% of its roads. - Abstract: Piezoelectric cymbals with 29-mm diameter and different configurations are fabricated and tested to determine the best conditions to optimize the conversion of mechanical to electric energy. Then, the ones with the best results are integrated directly in asphalt to evaluate their performance as vibration energy harvesters in roads, in a test bench designed to characterize these parameters. The main cymbal parameters and their integration in the asphalt are determined. For the first time, the electrical energy that can be obtained with the embedment of cymbals in asphalt is evaluated. Each single piezoceramic cymbal recovers up to 16 μW for the pass of one heavy vehicle wheel. An extrapolation of the energy transformed by the integrated cymbals in roads with high vehicle densities, such as in a peri-urban motorway, is approached. Energy densities in the range of 40–50 MW h/m"2 can be obtained at 100 m of road (use of 30,000 cymbals), which could account for more than 65 MW h in a year. All this with a relatively low cost for an emerging technology (less than 2 €/kW h). The conversion of wasted and unused vibrational energy in roads by piezoelectric cymbals is thus proved as a real possibility of

  14. Asphalt Concrete for Cold Regions, A Comparative Laboratory Study and Analysis of Mixtures Containing Soft and Hard Grades of Asphalt Cement,

    Science.gov (United States)

    1980-01-01

    Justification January 1980 BY Distribution Availabilit CodesIAvail an~d/or Dist special Prepa red for DIRECTORATE OF MILITARY PROGRAMS OFFICE, CHIEF OF...of water on the resilient modulus of asphalt treated mixes. Proecedinfp 4. Asphalt concrete mixes using the Tilton aggregates Association of Asphalt

  15. Mathematical and experimental investigations of modeling, simulation and experiment to promote the life-cycle of polymer modified asphalt.

    Science.gov (United States)

    2014-07-01

    The formulation of constitutive equations for asphaltic pavement is based on rheological models which include the asphalt mixture, additives, and the bitumen. In terms of the asphalt, the rheology addresses the flow and permanent deformation in time,...

  16. Storm Water General Permit 3 for Rock and Asphalt

    Data.gov (United States)

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

  17. Occupational Renal Dysfunction Among Asphalt Workers In Sharkia ...

    African Journals Online (AJOL)

    : An Epidemiological Study. ... Zagazig Journal of Occupational Health and Safety ... Abstract. Background: Occupational exposure to bitumen fumes emitted during hot application of asphalt carries the risk of exposure to significant amount of ...

  18. Quality control of recycled asphaltic concrete : final report.

    Science.gov (United States)

    1982-07-01

    This study examined the variations found in recycled asphaltic concrete mix based upon plant quality control data and verification testing. The data was collected from four recycled hot-mix projects constructed in 1981. All plant control and acceptan...

  19. Characteristic Asphalt Concrete Wearing Course (ACWC) Using Variation Lime Filler

    Science.gov (United States)

    Permana, R. A.; Pramesti, F. P.; Setyawan, A.

    2018-03-01

    This research use of lime filler Sukaraja expected add durability layers of concrete pavement is asphalt damage caused by the weather and load traffic. This study attempts to know how much value characteristic Marshall on a mixture of concrete asphalt using lime filler. This research uses experimental methods that is with a pilot to get results, thus will look filler utilization lime on construction concrete asphalt variation in filler levels 2 %, 3 %, 4 %.The results showed that the use of lime filler will affect characteristic a mixture of concrete asphalt. The more filler chalk used to increase the value of stability. On the cretaceous filler 2 % value of stability is 1067,04 kg. When lime filler levels added to the levels of filler 4 %, the value of stability increased to 1213,92 kg. The flexibility increased the number of filler as levels lime 2 % to 4 % suggests that are conducted more stiff mix.

  20. Density measurement verification for hot mix asphalt concrete pavement construction.

    Science.gov (United States)

    2010-06-01

    Oregon Department of Transportation (ODOT) requires a minimum density for the construction of dense-graded hot mix asphalt concrete (HMAC) pavements to ensure the likelihood that the pavement will not experience distresses that reduce the expected se...

  1. Density measurement verification for hot mixed asphalt concrete pavement construction.

    Science.gov (United States)

    2010-06-01

    Oregon Department of Transportation (ODOT) requires a minimum density for the construction of dense-graded hot mix asphalt concrete (HMAC) pavements to ensure the likelihood that the pavement will not experience distresses that reduce the expected se...

  2. Improving DMS 9210 requirements for limestone rock asphalt - final report.

    Science.gov (United States)

    2015-03-01

    Limestone Rock Asphalt (LRA) mixtures have been produced and placed for several decades using : specification requirements currently listed under DMS 9210. Several districts have had placement issues : and premature failures at the beginning of 2010....

  3. Connecticut warm mix asphalt (WMA) pilot projects 2010 and 2011.

    Science.gov (United States)

    2014-06-01

    WMA overlays were placed in several pilot projects in Connecticut during the 2010 and 2011 construction : seasons. These technologies included Sasobit, Evotherm, Advera, Double-Barrel Green foamed : asphalt as well as SonneWarmix. The res...

  4. Implementation of warm-mix asphalt mixtures in Nebraska pavements.

    Science.gov (United States)

    2012-07-01

    The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving : mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera : synthetic ...

  5. Performance of Virginia's warm-mix asphalt trial sections.

    Science.gov (United States)

    2010-02-01

    Three trial sections using two warm-mix asphalt (WMA) technologies were constructed in various locations in Virginia in 2006, and experiences with these trial sections were used in the development of the Virginia Department of Transportation's specia...

  6. Investigation of warm-mix asphalt for Iowa roadways.

    Science.gov (United States)

    2013-09-01

    Phase II of this study further evaluated the performance of plant-produced warm-mix asphalt (WMA) mixes by conducting : additional mixture performance tests at a broader range of temperatures, adding additional pavements to the study, comparing : vir...

  7. Assessment of Quality of Asphalt Concrete used in Road ...

    African Journals Online (AJOL)

    OLUWASOGO

    subjected to bitumen extraction and sieve analysis, hot mix Marshall Stability and flow tests, penetration and ... asphalt concrete as well as other structures of the flexible pavement. ... High-quality road networks are very important to the.

  8. Development of bio-based polymers for use in asphalt.

    Science.gov (United States)

    2014-02-01

    Asphalt binder is typically modified with poly type (styrene-butadiene-styrene or SBS) polymers to improve its rheological properties and performance grade. The elastic and principal component of SBS polymers is butadiene. For the last decade, butadi...

  9. Risk management of low air void asphalt concrete mixtures.

    Science.gov (United States)

    2013-07-01

    Various forms of asphalt pavement distress, such as rutting, shoving and bleeding, can be attributed, in many cases, to low air voids in : the mixtures during production and placement. The occurrence of low air void contents during plant production m...

  10. Towards analytical mix design for large-stone asphalt mixes.

    CSIR Research Space (South Africa)

    Rust, FC

    1992-08-01

    Full Text Available This paper addresses the development of an analytically based design procedure for large-aggregate asphalt and its application in thirteen trial sections. The physical and engineering properties of the various materials are discussed and related...

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

    DEFF Research Database (Denmark)

    Lee, Hosin; Kim, Yongjoo; Geisler, Nivi

    2009-01-01

    PMA where it is formulated to melt and blend with asphalt quickly during a batch mixing process. The main objectives of this study are to (1) build asphalt pavement using asphalt mixtures with SBS-based compound added using a “dry” process at the batch plant and (2) evaluate its performance under......-based compound seemed to affect the asphalt mix to become more flexible under the heavy loads. By adding SBS-based compound to asphalt mixtures using a “dry” process, it is expected that the pavement would become more resistant to rutting than a typical asphalt mixture used in Greenland while enduring its arctic...

  12. Production and performance of desulfurized rubber asphalt binder

    Directory of Open Access Journals (Sweden)

    Yanping Sheng

    2017-05-01

    Full Text Available Asphalt rubber binder typically exhibits disadvantages like segregation and high viscosity; however, this can be improved by the incorporation of desulfurized rubber powder. This study examined the swelling principle of desulfurized rubber asphalt (DRA. In addition, it evaluated the performance of DRA fabricated with various rubber powder contents under different shear conditions and development time. Superpave binders tests, including Brookfield viscosity, dynamic shear rheometer (DSR and bending beam rheometer (BBR tests, were applied on three control binders (i.e., neat, 20 mesh asphalt rubber binder, 40 mesh asphalt rubber binder and a DRA binder. Binder testing results indicated that rubber powder swelled into the base binder and resulted in enhanced stability. Optimum performance of the DRA binder was achieved by adding 20% (by weight of rubber powder into the base binder at shear rate, shear temperature, shear time and development time of 7000 r/min, 170 °C, 60 min and 45 min, respectively. Modified ranges of production conditions were also provided to widen the application of DRA in field construction. It appeared that DRA binder benefited from the recovered plasticity and viscosity of the rubber and consequently, exhibited superior performance over the neat and conventional asphalt rubber binders. Preliminary mixture evaluation was also conducted and the DRA binder was found to significantly improve the mixture resistance to permanent deformation and water damage. Overall, the DAR binder is encouraged to be used as a modified binder for flexible pavements. Keywords: Desulfurized rubber asphalt, Swelling model, Production process, Asphalt performance, Rubber asphalt

  13. Assessment of Asphalt Concrete Reinforcement Grid in Flexible Pavements

    Science.gov (United States)

    2016-05-01

    successfully used as interlayers include asphalt rubber and geotextiles, and the applica- tion of recycling techniques to rework the upper 2–4 in. of the...from a set of weights dropped from increasingly greater predetermined heights onto a rubber buffer system connected to a 12 in. diameter segmented...pavement temperature at depth, IR = the infrared pavement surface temperature (°C), D = the asphalt depth to estimate the temperature (mm), 1

  14. 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.

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

    Science.gov (United States)

    Sowah-Kuma, David

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

  16. Basic category theory

    CERN Document Server

    Leinster, Tom

    2014-01-01

    At the heart of this short introduction to category theory is the idea of a universal property, important throughout mathematics. After an introductory chapter giving the basic definitions, separate chapters explain three ways of expressing universal properties: via adjoint functors, representable functors, and limits. A final chapter ties all three together. The book is suitable for use in courses or for independent study. Assuming relatively little mathematical background, it is ideal for beginning graduate students or advanced undergraduates learning category theory for the first time. For each new categorical concept, a generous supply of examples is provided, taken from different parts of mathematics. At points where the leap in abstraction is particularly great (such as the Yoneda lemma), the reader will find careful and extensive explanations. Copious exercises are included.

  17. Laboratory Evaluation of Ground Tire Rubber in Stone Mastic Asphalt

    Directory of Open Access Journals (Sweden)

    R. Muniandy

    2004-12-01

    Full Text Available Stone mastic asphalt (SMA is a gap-graded mix whereby stiffer asphalt cement is required to bind the stone matrix or arrangement of stones together. Although various asphalt additives are traditionally available, the use of rubber crumbs in SMA is still a new rresearch endeavor. Many countries around the world are facing serious problems on what to do with reject or discarded tires. In the present study, commercial truck tires, containing 70% natural rubber, were ground and pre-blended in 80-100 penetration asphalt for use in SMA mixtures. An assessment was made of the laboratory performance of rubberized SMA in terms of stability, resilent modulus, dynamic creep and tensile strength ratio. It was observed that the performance of SMA with ground tire rubber was for superior as compared to SMA mix with unmodified asphalt. Sulfur and Styrene Butadeline Rubber (SBR were used in rubberized SMA mixes as additives to test the sensitivity of SMA mixtures. As standard practice a 0.3% newly developed cellulose oil palm fiber was used in SMA to minimize the asphalt drain-down effects.

  18. Performance of Hot Asphalt Mixtures Containing Plastic Bottles as Additive

    Directory of Open Access Journals (Sweden)

    Jan Hakeem

    2017-01-01

    Full Text Available This study focuses on evaluating the resistance of polymer modified asphalt mixes and the role played by asphalt in the realm of construction is undeniably important. Addition of polymers(PB as additives to asphalt helps to improve the strength and water repellent property of the mix and as well as helps environment in various ways and at the same time, analyzing its lower maintenance activities and service life is most important. The use of inexpensive polymers, in this case, waste polymers has without any doubt proven to be the most convenient way of reducing the cost of construction and at the same time maintaining quality. The main resolve for this research was to establish the effects of the use of plastic bottles on hot asphalt and its mixtures. In order to put this into perspective, varying percentages of asphalt mixtures were calculated and subjected to laboratory tests. The two-factor variance analysis (ANOVA was conducted to determine the significance at various confidence limits. The results indicate that the inclusion of Polyethylene Terephthalate (PET had a particularly substantial effect on the properties of asphalt. Consequently, it can encourage the re-utilization of waste in the manufacturing industry in an ecologically friendly and cost-effective way.

  19. The use of waste materials in asphalt concrete mixtures.

    Science.gov (United States)

    Tuncan, Mustafa; Tuncan, Ahmet; Cetin, Altan

    2003-04-01

    The purpose of this study was to investigate (a) the effects of rubber and plastic concentrations and rubber particle sizes on properties of asphalt cement, (b) on properties of asphalt concrete specimens and (c) the effects of fly ash, marble powder, rubber powder and petroleum contaminated soil as filler materials instead of stone powder in the asphalt concrete specimens. One type of limestone aggregate and one penetration-graded asphalt cement (75-100) were used. Three concentrations of rubber and plastic (i.e. 5%, 10% and 20% of the total weight of asphalt cement), three rubber particle sizes (i.e. No. 4 [4.75mm] - 20 [0.85 mm], No. 20 [0.85mm] - 200 [0.075mm] and No. 4 [4.75mm] - 200 [0.075mm]) and one plastic particle size (i.e. No. 4 [4.75mm] - 10 [2.00mm]) were also used. It was found that while the addition of plastic significantly increased the strength of specimens, the addition of rubber decreased it. No. 4 [4.75mm] - 200 [0.075mm] rubber particles showed the best results with respect to the indirect tensile test. The Marshall stability and indirect tensile strength properties of plastic modified specimens increased. Marble powder and fly ash could be used as filler materials instead of stone powder in the asphalt concrete pavement specimens.

  20. Reinforcement of Recycled Foamed Asphalt Using Short Polypropylene Fibers

    Directory of Open Access Journals (Sweden)

    Yongjoo Kim

    2013-01-01

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

  1. CHURCH, Category, and Speciation

    Directory of Open Access Journals (Sweden)

    Rinderknecht Jakob Karl

    2018-01-01

    Full Text Available The Roman Catholic definition of “church”, especially as applied to groups of Protestant Christians, creates a number of well-known difficulties. The similarly complex category, “species,” provides a model for applying this term so as to neither lose the centrality of certain examples nor draw a hard boundary to rule out border cases. In this way, it can help us to more adequately apply the complex ecclesiology of the Second Vatican Council. This article draws parallels between the understanding of speciation and categorization and the definition of Church since the council. In doing so, it applies the work of cognitive linguists, including George Lakoff, Zoltan Kovecses, Giles Fauconnier and Mark Turner on categorization. We tend to think of categories as containers into which we sort objects according to essential criteria. However, categories are actually built inductively by making associations between objects. This means that natural categories, including species, are more porous than we assume, but nevertheless bear real meaning about the natural world. Taxonomists dispute the border between “zebras” and “wild asses,” but this distinction arises out of genetic and evolutionary reality; it is not merely arbitrary. Genetic descriptions of species has also led recently to the conviction that there are four species of giraffe, not one. This engagement will ground a vantage point from which the Council‘s complex ecclesiology can be more easily described so as to authentically integrate its noncompetitive vision vis-a-vis other Christians with its sense of the unique place held by Catholic Church.

  2. Visual memory needs categories

    OpenAIRE

    Olsson, Henrik; Poom, Leo

    2005-01-01

    Capacity limitations in the way humans store and process information in working memory have been extensively studied, and several memory systems have been distinguished. In line with previous capacity estimates for verbal memory and memory for spatial information, recent studies suggest that it is possible to retain up to four objects in visual working memory. The objects used have typically been categorically different colors and shapes. Because knowledge about categories is stored in long-t...

  3. Libertarianism & Category-Mistake

    OpenAIRE

    Carlos G. Patarroyo G.

    2009-01-01

    This paper offers a defense against two accusations according to which libertarianism incurs in a category-mistake. The philosophy of Gilbert Ryle will be used to explain the reasons which ground these accusations. Further, it will be shown why, although certain sorts of libertarianism based on agent-causation or Cartesian dualism incur in these mistakes, there is at least one version of libertarianism to which this criticism does not necessarily apply: the version that seeks to find in physi...

  4. Convergence semigroup categories

    Directory of Open Access Journals (Sweden)

    Gary Richardson

    2013-09-01

    Full Text Available Properties of the category consisting of all objects of the form (X, S, λ are investigated, where X is a convergence space, S is a commutative semigroup, and λ: X × S → X is a continuous action. A “generalized quotient” of each object is defined without making the usual assumption that for each fixed g ∈ S, λ(., g : X  → X is an injection.

  5. Categories and Commutative Algebra

    CERN Document Server

    Salmon, P

    2011-01-01

    L. Badescu: Sur certaines singularites des varietes algebriques.- D.A. Buchsbaum: Homological and commutative algebra.- S. Greco: Anelli Henseliani.- C. Lair: Morphismes et structures algebriques.- B.A. Mitchell: Introduction to category theory and homological algebra.- R. Rivet: Anneaux de series formelles et anneaux henseliens.- P. Salmon: Applicazioni della K-teoria all'algebra commutativa.- M. Tierney: Axiomatic sheaf theory: some constructions and applications.- C.B. Winters: An elementary lecture on algebraic spaces.

  6. Adjusting Asphalt Mixes for Increased Durability and Implementation of a Performance Tester to Evaluate Fatigue Cracking of Asphalt

    Science.gov (United States)

    2018-01-17

    Cracking is a common failure mechanism in asphalt concrete pavement structures. It is one of the main reasons for large road maintenance and rehabilitation expenditures, as well as reduced user comfort and increased fuel consumption due to high road ...

  7. Rutting based evaluation of asphalt mixes

    International Nuclear Information System (INIS)

    Khan, K.M.

    2012-01-01

    Pavement rutting is one of the most common and destructive pavement distresses being observed in flexible pavements, which is primarily due to a-x-le loads that exceed legal limit and high ambient temperatures, and also poor mix design is one of the cause of rutting. The drastic increase in traffic volume during last few decades has resulted in premature pavement fillers of almost the whole road structure in Pakistan. In this scenario it is the time to investigate this problem and propose appropriate solution. Physical properties of aggregates and bitumen were evaluated in the laboratory. Mechanical Properties of three mixes. i.e., Marshall, Super pave and Stone Mastic Asphalt (SMA) were evaluated by performing creep test. indirect tensile test and dynamic modulus in order to compare the performance of mixes under prevailing load and environmental conditions of Pakistan. The study revealed that Super pave mixes performed better than Marshall and SMA. (author)

  8. Neutron and gamma ray attenuation of asphalt; Comparison with paraffin and water

    International Nuclear Information System (INIS)

    Abdul-Majid, S.; Kutbi, I.I.

    1996-01-01

    Asphalt is a low cost, readily available, easy-to-cast material which is rich in hydrogen and carbon, elements most effective for fast-neutron shielding. Unlike paraffin, the material can easily be mixed with boron containing compounds, an, element of high absorption cross-section for slow neutrons. The 241 Am-Be neutron and gamma attenuation characteristic of asphalt were studied. The source is having wide applications in industry and geophysics field work. Comparisons were made with paraffin and water. The source activity was 1.11 x 1,011 Bq (3 Ci) with a neutron emission rate of 6.6 x 106 n s -1 and a tolerance of +10%. The neutron dose-equivalent rate at 1 m was 66 mSv h -1 , while the associated gamma ray exposure was ∼1.9 mC kg -1 h -1 of the bare source. A neutron remmeter was used for the neutron dose-equivalent rate measurements, which produces an energy response that approximates human body dose equivalent over a wide range of neutron energy. An air filled ionization chamber was used for the exposure rate measurements. The slow neutrons were measured by a BF 3 gas filled detector. The shielding materials were confined in an aluminum cylinder of 1 mm wall thickness where the source was kept in the middle. The neutron dose rate, the gamma ray exposure rate, and the slow neutron count rate were measured at different shield radii and at different distances from its outer surface. The neutron doses of asphalt at the surface of cylindrical shields of 8, 12, 16, 20, and 24 cm radii in mSv h -1 were 0.85, 0.4, 0.25, 0.13, and 0.06, respectively, while the gamma ray exposure mC kg -1 h -1 were 7, 4.4 2.5, 1.3, and 0.88, respectively. The neutron dose rate attenuation of asphalt was very close to that of water, but slightly lower than that of paraffin, while the gamma ray attenuation was close to that of water but higher than that of paraffin

  9. Investigation on performances of asphalt mixtures made with Reclaimed Asphalt Pavement: Effects of interaction between virgin and RAP bitumen

    Directory of Open Access Journals (Sweden)

    Luca Noferini

    2017-07-01

    Full Text Available According to most recent surveys, the European area produced 265 mil tonnes of asphalt for road applications in 2014. In the same year, the amount of available RAP was more than 50 mil tonnes. The use of RAP in new blended mixes reduces the need of neat bitumen, making RAP recycling economically attractive. Despite the economic and environmental benefits, road authorities tend to limit the use of RAP in asphalt mixes due to uncertainty about field performances. The present study focuses on the interaction between neat and RAP bitumen in asphalt mixes made with different RAP content. The effects of RAP on physical and rheological properties of the final bituminous blend were investigated. This study is part of a wider research, where a specific type of asphalt mixture was produced with different RAP contents being 10%, 20% and 30% by mass of the mix. Bitumen was extracted and recovered from asphalt mixes, then it was subjected to the following laboratory tests: standard characterization, dynamic viscosity and rheological analysis with DSR. Findings showed that the effects of RAP bitumen on the final blend varied in proportion to RAP content. A threshold value of RAP content was found, below which bitumen was not subjected to significant changes in physical and rheological properties. Practical implications on production methods and paving of RAP mixes are also proposed. Keywords: Reclaimed Asphalt Pavement (RAP, Recycling, Bitumen blending, Bitumen rheology

  10. LIBERTARISMO & ERROR CATEGORIAL

    Directory of Open Access Journals (Sweden)

    Carlos G. Patarroyo G.

    2009-01-01

    Full Text Available En este artículo se ofrece una defensa del libertarismo frente a dos acusaciones según las cuales éste comete un error categorial. Para ello, se utiliza la filosofía de Gilbert Ryle como herramienta para explicar las razones que fundamentan estas acusaciones y para mostrar por qué, pese a que ciertas versiones del libertarismo que acuden a la causalidad de agentes o al dualismo cartesiano cometen estos errores, un libertarismo que busque en el indeterminismo fisicalista la base de la posibilidad de la libertad humana no necesariamente puede ser acusado de incurrir en ellos.

  11. Libertarianism & Category-Mistake

    Directory of Open Access Journals (Sweden)

    Carlos G. Patarroyo G.

    2009-12-01

    Full Text Available This paper offers a defense against two accusations according to which libertarianism incurs in a category-mistake. The philosophy of Gilbert Ryle will be used to explain the reasons which ground these accusations. Further, it will be shown why, although certain sorts of libertarianism based on agent-causation or Cartesian dualism incur in these mistakes, there is at least one version of libertarianism to which this criticism does not necessarily apply: the version that seeks to find in physical indeterminism the grounding of human free will.

  12. Libertarismo & Error Categorial

    OpenAIRE

    PATARROYO G, CARLOS G

    2009-01-01

    En este artículo se ofrece una defensa del libertarismo frente a dos acusaciones según las cuales éste comete un error categorial. Para ello, se utiliza la filosofía de Gilbert Ryle como herramienta para explicar las razones que fundamentan estas acusaciones y para mostrar por qué, pese a que ciertas versiones del libertarismo que acuden a la causalidad de agentes o al dualismo cartesiano cometen estos errores, un libertarismo que busque en el indeterminismo fisicalista la base de la posibili...

  13. Mechanical characterization of porous asphalt mixes modified with fatty acid amides -FAA-

    Directory of Open Access Journals (Sweden)

    Vanessa Senior Arrieta

    2017-01-01

    Full Text Available Porous asphalt mixes (PAM, form a special road surface for asphalt pavement structures, have a special particle size distribution that lets infiltrate to the runoff storm water through of it because of its voids content about 20 %. Many researchers conducted studies and have concluded that the use of modified asphalts is completely necessary to design PAM. Organic and chemical additives and special procedures as foamed asphalt have enhanced the performance of PAM, during their service life. This paper is focused on the mechanical characterization of PAM and how the asphalt modified with fatty acid amides, influenced on their behavior and performance. Based on an experimental methodology with laboratory tests aimed at establishing a comparison between porous asphalt mixes, using for its design and production a penetration 60-70 pure asphalt and another one asphalt modified with fatty acid amides.

  14. Validity of multiple stress creep recovery (MSCR) test for DOTD asphalt binder specification : technical summary.

    Science.gov (United States)

    2017-09-01

    Higher traffic coupled with heavier loads led the asphalt industry to introduce polymer-modified binders to enhance the durability and strength of hot mix asphalt (HMA) pavements. When the Superpave Performance Graded (PG) binder specification (AASHT...

  15. Assessment of asphalt concrete reinforcement grid in flexible pavements : final report.

    Science.gov (United States)

    2016-05-01

    This report investigated the application of accepted methods of pavement structural evaluation to independently assess the potential structural benefit of asphalt geogrid reinforcement of an operational flexible highway pavement. The asphalt interlay...

  16. Quantifying Asphalt Emulsion-Based Chip Seal Curing Times Using Electrical Resistance Measurements.

    Science.gov (United States)

    2017-04-15

    Chip sealing typically consists of covering a pavement surface with asphalt emulsion into which aggregate chips are embedded. The asphalt emulsion cures through the evaporation of water, thus providing mechanical strength to adhere to the pavement wh...

  17. 0-6686 : improving DMS 9210 requirements for limestone rock asphalt : [project summary].

    Science.gov (United States)

    2013-08-01

    Limestone rock asphalt (LRA) mixtures have : been produced and placed for several decades : using specification requirements currently listed : under DMS 9210, Limestone Rock Asphalt (LRA). : Several Texas Department of Transportation : (TxDOT) distr...

  18. Performance Assessment of Warm Mix Asphalt (WMA) Pavements : Executive Summary Report

    Science.gov (United States)

    2009-09-01

    Warm Mix Asphalt (WMA) is a new technology which was : introduced in 1995 in Europe. WMA is gaining attention all : over the world because it offers several advantages over : conventional asphalt concrete mixes. The benefits include: : (1) Reduced en...

  19. Performance Measures of Warm Asphalt Mixtures for Safe and Reliable Freight Transportation

    Science.gov (United States)

    2009-04-01

    Warm mix asphalt (WMA) is an emerging technology that can allow asphalt to flow at a lower temperature for mixing, placing and compaction. The advantages of WMA include reduced fuel consumption, less carbon dioxide emission, longer paving season, lon...

  20. Pavement service life extension due to asphalt surface treatment interlayer : research project capsule.

    Science.gov (United States)

    2016-07-01

    The Louisiana Department of Transportation and Development (DOTD) has been : using asphalt surface treatment (AST) interlayers over soil cement base courses : as a means to mitigate shrinkage cracks from reflecting through the asphaltic : concrete (A...

  1. Fatigue and fracture properties of aged binders in the context of reclaimed asphalt mixes.

    Science.gov (United States)

    2014-08-01

    Evidence in the literature indicates that the stiffness of the asphalt binder increases and ductility of the binder decreases : with oxidative aging. Typically for unmodified asphalt binders, increase in stiffness or decrease in ductility is regarded...

  2. In-Place Recycling and Reclamation of Asphaltic Concrete Pavements in Kentucky

    Science.gov (United States)

    2017-11-01

    Full-depth reclamation has been defined by the Asphalt Recycling and Reclaiming Association as a rehabilitation technique in which the full thickness of the asphalt pavement and a predetermined portion of the underlying material (base, subbase, an...

  3. Improving Quality Control of Asphalt Pavement with RAP Using a Portable Infrared Spectroscopy Device

    Science.gov (United States)

    2016-04-01

    This project has investigated the effectiveness of a Portable Infrared Spectrometer (PIRS) device in estimating percent of Reclaimed Asphalt Pavement (RAP) and its contribution into oxidative aging of a new asphalt mixture immediately after productio...

  4. The road that's taken : Alberta's bitumen and the world of asphalt

    International Nuclear Information System (INIS)

    Bentein, J.

    2009-01-01

    Approximately one third of the bitumen produced by the oil sands industry in Canada is used as asphalt in roads and roofing materials. Crude oils used for asphalt production require very little refining. The asphalt market has become a key profit centre for some Cold Lake operators. Imperial Oil has established a research centre devoted to asphalt production at its Sarnia-based refinery. A decline in heavy oil supplies from Mexico and Venezuela has left Canada with a larger margin of the asphalt market. Industry leaders predict that demand for asphalt products will grow by 2.6 per cent per year. A sharp increase in asphalt prices led to many construction delays in 2007. Trials are now being conducted on a new warm mix paving technology that allows users to lower the temperature of asphalt by 20 to 30 degrees C when paving. 2 figs

  5. Evaluation of cement and fly ash treated recycled asphalt pavement and aggregates for base construction.

    Science.gov (United States)

    2011-12-01

    Many entities currently use recycled asphalt pavement (RAP) and other aggregates as base material, temporary haul roads, : and, in the case of RAP, hot mix asphalt construction. Several states currently allow the use of RAP combined with cement : for...

  6. A Review of the Application of Zeolite Materials in Warm Mix Asphalt Technologies

    Directory of Open Access Journals (Sweden)

    Agnieszka Woszuk

    2017-03-01

    Full Text Available Among warm mix asphalt (WMA technologies, asphalt foaming techniques offer high potential in terms of decreasing production temperature. Reluctance of manufacturers to introduce this technology is connected with the concerns of a large investment costs. However, there are known additives which, through asphalt foaming, allow a decrease in temperatures by approximately 30 °C; the use of these additives do not involve expensive investment in order to change the asphalt mix production method. These additives are zeolites, that is, minerals of the aluminosilicate group, the crystalline structure of which contains water bound in a specific way. Its release, at mix asphalt production temperatures, causes asphalt foaming. It is currently known that zeolites can be used in WMA, including natural and synthetic zeolites obtained using chemical reagents and waste. This review presents the results of studies of WMA technology, including the effects of zeolite addition on asphalt properties and mix asphalt, as well as related environmental, economic, and technological benefits.

  7. Performance of Hot Mix Asphalt Mixture Incorporating Kenaf Fibre

    Science.gov (United States)

    Hainin, M. R.; Idham, M. K.; Yaro, N. S. A.; Hussein, S. O. A. E.; Warid, M. N. M.; Mohamed, A.; Naqibah, S. N.; Ramadhansyah, P. J.

    2018-04-01

    Kenaf fibre has been recognised to increase the strength of concrete, but its application in asphalt concrete is still unanswered. This research investigated the performance of Hot Mix Asphalt (HMA) incorporated with different percentages of kenaf fibre (0.1 %, 0.2% and 0.3% by weight of dry aggregate) in term of resilient modulus, rutting performance using Asphalt Pavement analyser (APA) and moisture damage using the Modified Lottman test (AASHTO-T283). The fibre was interweaved to a diameter of about 5-10 mm and length of 30 mm which is three times the nominal maximum aggregate size used in the mix. Asphaltic mixtures of asphalt concrete (AC) 10 were prepared and compacted using Marshall compactor which were subsequently tested to evaluate the resilient modulus and moisture susceptibility. Twelve cylindrical specimens (150mm diameter) from AC10, two control samples with two modified ones for each percentage of kenaf fibres compacted using Gyratory compactor were used for rutting test using APA. The laboratory results reveal that the addition of kenaf fibres slightly reduce the resilient modulus of the mixes and that asphaltic mix with 0.3% kenaf fibre can mitigate both rutting and moisture damage which makes the pavement more sustain to the loads applied even in the presence of water. 0.3% kenaf fibre content is considered to be the optimal content which had the least rut depth and the highest TSR of 81.07%. Based on grid analysis, addition of 0.3% kenaf fibre in asphaltic concrete was recommended in modifying the samples.

  8. Asphalt Roofing Shingles Into Energy Project Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Jameson, Rex, PE

    2008-04-28

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

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

    Directory of Open Access Journals (Sweden)

    Yuqiao Yang

    2016-01-01

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

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

    Science.gov (United States)

    Asphalt Inst., College Park, MD.

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

  11. Survey of microbial degradation of asphalts with notes on relationship to nuclear waste management

    International Nuclear Information System (INIS)

    ZoBell, C.E.; Molecke, M.A.

    1978-12-01

    A survey has been made of the microbial degradation of asphalts. Topics covered include chemical and physical properties of asphalts, their chemical stability, methods of demonstrating their microbial degradation, and environmental extremes for microbial activity based on existing literature. Specific concerns for the use of asphalt in nuclear waste management, plus potential effects and consequences thereof are discussed. 82 references

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

    NARCIS (Netherlands)

    Vasenev, Alexandr

    2015-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2016-08-01

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

  15. Basic Performance of Fibre Reinforced Asphalt Concrete with Reclaimed Asphalt Pavement Produced In Low Temperatures with Foamed Bitumen

    Science.gov (United States)

    Chomicz-Kowalska, Anna; Iwański, Mateusz M.; Mrugała, Justyna

    2017-10-01

    During the reconstruction of road pavements, the reclaimed asphalt pavement (RAP), which is obtained through milling of the worn out existing asphalt, is commonly used for producing new base courses in cold recycling processes. Two of these techniques are most popular: one using mineral-cement-emulsion mixes and one utilizing mineral cement mixes with foamed bitumen. Additionally, some amounts of RAP can be incorporated into traditional hot mix asphalt. The demand for energy efficient and environmentally friendly solutions however, results in a need for development of new techniques that would result in cheaper and more reliable solutions with smaller carbon footprint. The reduction of processing temperatures with simultaneous incorporation of reclaimed material is the most efficient way of obtaining these objectives, but it often results in the overall decrease of bituminous mix quality. The paper presents the possibility of using RAP for producing asphalt concrete in warm mix asphalt (WMA) production process by the use of foamed bitumen modified with Fischer-Tropsch synthetic wax and polymer-basalt fibers. Additionally, a series of reference mixtures were produced to investigate the effects of the additives and of the warm process. The carried out analyses and tests shown that the experimental warm mix asphalt produced with RAP and foamed bitumen returned satisfactory performance. The introduction of synthetic F-T wax in the warm foam bitumen mixes resulted in a significantly improved compaction levels and moisture and frost resistance and the addition of polymer-basalt fibers has further improved the permanent deformation resistance of the mixes. All of the designed and tested mixes have fulfilled the requirements for binding course asphalt concrete with medium traffic loads.

  16. Beyond the Categories.

    Science.gov (United States)

    Weeks, Jeffrey

    2015-07-01

    Shushu is a Turkish Cypriot drag performance artist and the article begins with a discussion of a short film about him by a Greek Cypriot playwright, film maker, and gay activist. The film is interesting in its own right as a documentary about a complex personality, but it is also relevant to wider discussion of sexual and gender identity and categorization in a country divided by history, religion, politics, and military occupation. Shushu rejects easy identification as gay or transgender, or anything else. He is his own self. But refusing a recognized and recognizable identity brings problems, and I detected a pervasive mood of melancholy in his portrayal. The article builds from this starting point to explore the problematic nature of identities and categorizations in the contemporary world. The analysis opens with the power of words and language in defining and classifying sexuality. The early sexologists set in motion a whole catalogue of categories which continue to shape sexual thinking, believing that they were providing a scientific basis for a more humane treatment of sexual variations. This logic continues in DSM-5. The historical effect, however, has been more complex. Categorizations have often fixed individuals into a narrow band of definitions and identities that marginalize and pathologize. The emergence of radical sexual-social movements from the late 1960s offered new forms of grassroots knowledge in opposition to the sexological tradition, but at first these movements worked to affirm rather than challenge the significance of identity categories. Increasingly, however, identities have been problematized and challenged for limiting sexual and gender possibilities, leading to the apparently paradoxical situation where sexual identities are seen as both necessary and impossible. There are emotional costs both in affirming a fixed identity and in rejecting one. Shushu is caught in this dilemma, leading to the pervasive sense of loss that shapes the

  17. The mechanical behavior of two warm-mix asphalts

    Directory of Open Access Journals (Sweden)

    H. A. Rondón-Quintana

    2016-09-01

    Full Text Available This paper presents results stemming from a comparative experimental analysis of two warm-mix asphalts (WMA and a dense-graded hot-mix asphalt (HMA. In order to evaluate asphalt mixture behavior, physical and rheological tests were conducted, including tests on resilient modulus, resistance to moisture-induced damage, resistance to fatigue and resistance to permanent deformation. Samples studied were subjected to short (STOA and long-term (LTOA aging. As far as asphalt mixture composition is concerned, the same particle size distribution and coarse aggregate were employed for both mixture types. The control HMA mixture was produced with AC 60-70, and the WMAs used the same asphalt cement modified with two chemical additives (Rediset WMX® and Cecabase RT®. The modified mixtures exhibited better resistance to permanent deformation, aging and moisture-induced damage (versus the control mixture. Likewise, WMAs generally saw increased fatigue resistance under controlled-stress loading, which rheological characterization showed is mainly attributable to binder additives and their concomitant modifications.

  18. Laboratory Evaluation of Aging Behaviour of SBS Modified Asphalt

    Directory of Open Access Journals (Sweden)

    Jie Wang

    2017-01-01

    Full Text Available To study the effect of aging SBS modified asphalt on the performance of asphalt pavement, aging at various times and temperatures was conducted with thin film oven, and then tests were made about the penetration, softening point, ductility, viscosity, toughness, and fluorescence microscopy of modified asphalt with different aging levels. The results show that, with the increasing of aging time, the penetration and ductility of modified asphalt decrease while its softening point and viscosity increase, and the variation trend of the toughness and tenacity is related to the aging temperature; the aging dynamic model with viscosity as parameter can well characterize the aging process of modified asphalt; at microlevel, with the decreasing of SBS particle size, the uniformity of particle size is better. Analysis of macroscopic properties, microscopic characteristics, and significance shows that the SBS particle area ratio has a significant correlation with tenacity as the aging temperature changes. When the aging temperature is 163°C, the SBS particle area ratio still has a significant correlation with tenacity as the aging time changes.

  19. Significance of Fines in Hot Mix Asphalt Synthesis

    Directory of Open Access Journals (Sweden)

    Kalaitzaki Elvira

    2017-07-01

    Full Text Available According to their size, aggregates are classified in coarse grained, fine grained, and fines. The determination of fines content in aggregate materials is very simple and is performed through the aggregate washing during the sieving procedure to define the gradation curve. The very fine material consists of grains having a size lower than 63 μm. The presence of fines directly influences the composition and performance of concrete and asphalt mixtures (e.g. asphalt content, elasticity, fracture. The strength and load carrying capacity of hot mix asphalt (HMA results from the aggregate framework created through particle-particle contact and interlock. Fines or mineral filler have a role in HMA. The coarse aggregate framework is filled by the sand-sized material and finally by the mineral filler. At some point, the smallest particles lose contact becoming suspended in the binder not having the particle-particle contact that is created by the larger particles. The overall effect of mineral filler in hot mix asphalt specimens has been investigated through a series of laboratory tests. It is clear that a behaviour influenced by the adherence of fines to asphalt film has been developed. The optimum bitumen content requirement in case of stone filler is almost the same as that for fly ash. It has been found that the percentage of fly ash filler is crucial if it exceeds approximately a value of 4%.

  20. UTILIZATION OF WASTE PLASTIC BOTTLES IN ASPHALT MIXTURE

    Directory of Open Access Journals (Sweden)

    TAHER BAGHAEE MOGHADDAM

    2013-06-01

    Full Text Available Nowadays, large amounts of waste materials are being produced in the world. One of the waste materials is plastic bottle. Generating disposable plastic bottles is becoming a major problem in many countries. Using waste plastic as a secondary material in construction projects would be a solution to overcome the crisis of producing large amount of waste plastics in one hand and improving the structure’s characteristics such as resistance against cracking on the other hand. This study aimed to investigate the effects of adding plastic bottles in road pavement. Marshall properties as well as specific gravity of asphalt mixture containing different percentages of plastic bottles were evaluated. Besides, Optimum Asphalt Content (OAC was calculated for each percentages of plastic bottles used in the mix. The stiffness and fatigue characteristics of mixture were assessed at OAC value. Results showed that the stability and flow values of asphalt mixture increased by adding waste crushed plastic bottle into the asphalt mixture. Further, it was shown that the bulk specific gravity and stiffness of mixtures increased by adding lower amount of plastic bottles; however, adding higher amounts of plastic resulted in lower specific gravity and mix stiffness. In addition, it was concluded that the mixtures containing waste plastic bottles have lower OAC values compared to the conventional mixture, and this may reduce the amount of asphalt binder can be used in road construction projects. Besides, the mixtures containing waste plastic showed significantly greater fatigue resistance than the conventional mixture.

  1. Experimental Study on Color Durability of Color Asphalt Pavement

    Science.gov (United States)

    Ning, Shi; Huan, Su

    2017-06-01

    Aiming at the poor Color durability and the lack of research on Color asphalt pavement, spraying an anti-tire trace seal resin emulsion on the surface, a Color durable asphalt pavement was proposed. After long-term rolling and long-term aging test, the Color durability was evaluated by RGB function in Photoshop and trace residue rate formula. Test results proved that the Evaluation method was simple and effective. After long-term rolling, the Color of the road surface tends to a constant value. Spraying the emulsion on the road surface can resist tire traces. After long-term aging test, the resistance to tire traces was increased by 26.6% compared with the conventional type, while the former was 44.1% higher than the latter without long-term aging. The Color durable asphalt pavement can effectively improve the ability of Color asphalt pavement to resist tire traces, and significantly improve the Color durability of Color asphalt pavement.

  2. Aging test results of an asphalt membrane liner

    International Nuclear Information System (INIS)

    Buelt, J.L.; Barnes, S.M.

    1983-07-01

    The objective of the asphalt aging study described in this report was to determine the expected performance lifetime of a catalytically airblown asphalt membrane as a seepage barrier for inactive uranium mill tailings. The study, conducted by Pacific Northwest Laboratory for the Department of Energy's Uranium Mill Tailings Remedial Action Program, showed through chemical compatibility tests that the asphalt membrane is well suited for this purpose. The chemical compatibility tests were designed to accelerate the aging reactions in the asphalt and to determine the accelerated aging effect. Higher temperatures and oxygen concentrations proved to be effective acceleration parameters. By infrared spectral analysis, the asphalt was determined to have undergone 7 years of equivalent aging in a 3-month period when exposed to 40 0 C and 1.7 atm oxygen pressure. However, the extent of aging was limited to a maximum penetration of 0.5% of the total liner thickness. It was concluded that the liner could be expected to be effective as a seepage barrier for at least 1000 years before the entire thickness of the liner would be degraded

  3. Partial substitution of asphalt pavement with modified sulfur

    Directory of Open Access Journals (Sweden)

    E.R. Souaya

    2015-12-01

    Full Text Available The use of sulfur in pavement laying was developed in 1980 but it was restricted in the late 19th century due to its environmental problems and its high reactivity toward oxidation processes which give sulfuric acid products that are capable of destroying the asphalt mixture. The study involved the conversion of elemental sulfur to a more stable modified one using a combination of byproducts of olefin hydrocarbons that were obtained from petroleum fractional distillates and cyclic hydrocarbon bituminous residue at 145 °C. The changes in the structural characteristics and morphology of prepared modified sulfur were studied using XRD and SEM respectively. Also DSC curves help us to elucidate the changes in sulfur phases from α-orthorhombic to β-mono clinic structure. The technique of nanoindentation helps us to compare the mechanical properties of modified and pure sulfur including modulus of elasticity and hardness. The hot mixture asphalt designs were prepared according to the Marshall Method in which the asphalt binder content was partially substituted with 20%, 30%, 40%, and 50% modified sulfur. The mechanical properties were measured including Marshall Stability, flow, air voids, and Marshall Stiffness. From the overall study, the results indicated that asphalt could partially be substituted with modified sulfur with no significant deleterious effect on performance and durability of hot mixed asphalt.

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

    Directory of Open Access Journals (Sweden)

    Wenbo Zeng

    2017-01-01

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

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

    Science.gov (United States)

    Zeng, Wenbo; Wu, Shaopeng; Pang, Ling; Sun, Yihan; Chen, Zongwu

    2017-01-07

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

  6. Performance of Asphalt Concrete Wearing Course (AC-WC) Utilizing Reclaimed Asphalt Pavement from Cold Milling Bound with 80/100 Pen Asphalt

    Science.gov (United States)

    Thanya, I. N. A.; Suweda, I. W.; Putra, G. K.

    2018-03-01

    Demands on natural aggregate materials for road pavement can be reduced by utilizing reclaimed asphalt pavement (RAP). This research was aimed at evaluating the performance of AC-WC mixture using RAP materials from cold milling, bound with 80/100 pen asphalt. The RAP aggregate gradation was adjusted by adding the required amount of natural aggregates to meet the specification in Indonesia. The RAP and added aggregates were hotmixed and compacted with Marshall hummer at 2×75 blows. The asphalt content were varied. It was found that the optimum asphalt content was 6.05 % with the following Marshall characteristics: stability 1237.08 kg; flow 3.36 mm; Marshall quotient 324,73kg/mm; void in mix (VIM) 3,360%; void in mineral aggregate (VMA) 15.103; and void filled with bitumen (VFB) 77.759% and residual stability 91.04; all met the Indonesian specification. The cantabro abration loss (CAL) at 30°C was 9,02%. The indirect tensile stiffness modulus (ITSM) at 20 °C was 7961.4 MPa; dynamic creep with 100 kPa pressure at 40°C gave slope 0.0112 microsstrain/pulse which is suitable for heavy load traffic. The fatigue test results was obtained at increased stress level, i.e. at 900, 1100, and 1300 kPa. Based on the equation derived from the fatigue strain and repeated loading relationship, at 100 microstrain (με) the repeated load was 434,661.58 times, and at one million (106) repeated loading, the samples could withstand strain of 92,38 microstrain. The performance of the samples were overall better than AC-WC mixture using virgin aggregates bound with 60/70 pen asphalt.

  7. Viscoelastic behaviour of cold recycled asphalt mixes

    Science.gov (United States)

    Cizkova, Zuzana; Suda, Jan

    2017-09-01

    Behaviour of cold recycled mixes depends strongly on both the bituminous binder content (bituminous emulsion or foamed bitumen) and the hydraulic binder content (usually cement). In the case of cold recycled mixes rich in bitumen and with low hydraulic binder content, behaviour is close to the viscoelastic behaviour of traditional hot mix asphalt. With decreasing bituminous binder content together with increasing hydraulic binder content, mixes are characteristic with brittle behaviour, typical for concrete pavements or hydraulically bound layers. The behaviour of cold recycled mixes with low content of both types of binders is similar to behaviour of unbound materials. This paper is dedicated to analysing of the viscoelastic behaviour of the cold recycled mixes. Therefore, the tested mixes contained higher amount of the bituminous binder (both foamed bitumen and bituminous emulsion). The best way to characterize any viscoelastic material in a wide range of temperatures and frequencies is through the master curves. This paper includes interesting findings concerning the dependency of both parts of the complex modulus (elastic and viscous) on the testing frequency (which simulates the speed of heavy traffic passing) and on the testing temperature (which simulates the changing climate conditions a real pavement is subjected to).

  8. Thermal and hydraulic analysis of multilayered asphalt pavements as active solar collectors

    International Nuclear Information System (INIS)

    Pascual-Muñoz, P.; Castro-Fresno, D.; Serrano-Bravo, P.; Alonso-Estébanez, A.

    2013-01-01

    Highlights: • A new type of asphalt solar collector has been introduced in this paper. • The common pipe network has been replaced for a highly porous asphalt layer. • The use of these collectors contributes to achieve current environmental targets. • Excellent thermal efficiencies have been obtained in the laboratory tests. • Further research is needed to increase the low flow rates achieved. - Abstract: The fulfillment of current environmental aims like reducing fossil fuel consumption or greenhouse gas emissions entails the development of new technologies that enable the use of cleaner, cheaper and renewable energies. Furthermore, the need to improve energy efficiency in buildings encourages scientists and engineers to find new ways of harvesting energy for later uses. The use of asphalt pavements as active solar collectors is introduced in this article. Several authors have studied the use of roads as an energy source before. However, a new technology is presented in which a multilayered pavement with a highly porous middle layer is used instead of a solar collector with an embedded pipe network. These collectors are fully integrated within the road infrastructure and may offer low cost solar energy for water heating. The paper includes a brief comment on the state-of-the-art. Then, a broad methodology is presented in which data, materials and procedures needed to run the tests are fully described. Finally, the results of the laboratory tests are stated and discussed. The prototype used in the laboratory provided excellent thermal efficiency. However, these good results contrast with the low flow rate levels registered during the tests. Thus, although this technology seems to be very promising, new experimental tests should be performed before an effective application is possible

  9. Laboratorium Study of Asphalt Starbit E-55 Polymer Modified Application on Asphalt Concrete Wearing Course (Ac-Wc

    Directory of Open Access Journals (Sweden)

    Damianus Kans Pangaraya

    2015-09-01

    Full Text Available The conventional asphalt road has almost been considered fail to serve the transportation needs. It is indicated by the occurrence of premature damage which is caused by vehicle load and climate. Starbit E-55, the polymer modified bitumen, is formulated to meet the requirement of transport development. Considering those needs, it is important to investigate the feasibility level of that modified bitumen as alternate asphalt instead of the conventional one. This research began with the measurement of the properties of hard layered AC-WC Starbit E-55, then comparing the result to 60/70 penetration of Pertamina asphalt. The next step is then, to determine the converted value so as to be close to that of Pertamina (60/70 penetration. This step is conducted by applying durability and ITS tests on the mixture. Result of the tests showed that hard layered AC-WC Starbit E-55 has better characteristic at 5.7% optimum level asphalt and 6.4% of Pertamina asphalt (60/70 penetration. Starbit E-55 converted level within hard-layered ACWC is 5.6%. The performance test result on immersion with variance of 1, 3, 5, 7 and 14 days shows that durability value of Starbit E-55 AC-WC has better performance. During the process, Starbit E-55 required 15.38% higher energy consumption.

  10. Investigation of Asphalt Mixture Creep Behavior Using Thin Beam Specimens

    International Nuclear Information System (INIS)

    Zofka, Adam; Marasteanu, Mihai; Turos, Mugur

    2008-01-01

    The asphalt pavement layer consists of two or more lifts of compacted asphalt mixture; the top of the layer is also exposed to aging, a factor that significantly affects the mixture properties. The current testing specifications use rather thick specimens that cannot be used to investigate the gradual change in properties with pavement depth. This paper investigates the feasibility of using the 3-point bending test with thin asphalt mixture beams (127x12.7x6.35 mm) to determine the low-temperature creep compliance of the mixtures. Several theoretical and semi-empirical models, from the theory of composites, are reviewed and evaluated using numerical and experimental data. Preliminary results show that this method can be used for low-temperature mixture characterization but several crucial factors need further inspection and interpretation

  11. Effect of ageing on porosity of hot mix asphalt

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, M.F.A.S. [Dept. de Estradas de Rodagem de Minas Gerais (DER/MG), Belo Horizonte, MG (Brazil); Lins, V.F.C. [Universidade Federal de Minas Gerais (UFMG), MG (Brazil). Dept. de Engenharia Quimica], e-mail: vlins@deq.ufmg.br; Pasa, V.M.D. [Universidade Federal de Minas Gerais (UFMG), MG (Brazil). Dept. de Quimica

    2011-01-15

    Asphalt ageing due to the action of solar radiation must be considered in the study of the performance of asphalt pavement, especially in Brazil because of its geographical characteristics. The aim of this work is to study asphalt ageing caused by the effect of xenon radiation, by using weathering tests. Sample degradation was evaluated by using Fourier transform infrared spectroscopy (FTIR). The results of FTIR indicated an oxidation process of the material, which occurred during exposure in the xenon arc chamber. The area ratio related to the bands of the aliphatic CH/OH and CH/C=O groups and those of the Si-O-Si/OH groups of bitumen decreased after exposure to xenon radiation. The samples were analyzed by using X-ray fluorescence (XRF) and scanning electron microscopy (SEM). The porosity of the samples before and after ageing was measured by using the SEM micrographs and the image software Quantikov. (author)

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

    International Nuclear Information System (INIS)

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

    1981-05-01

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

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

    International Nuclear Information System (INIS)

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

    1994-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-05-01

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

  15. Stability and Volumetric Properties of Asphalt Mixture Containing Waste Plastic

    Directory of Open Access Journals (Sweden)

    Abd Kader Siti Aminah

    2017-01-01

    Full Text Available The objectives of this study are to determine the optimum bitumen content (OBC for every percentage added of waste plastics in asphalt mixtures and to investigate the stability properties of the asphalt mixtures containing waste plastic. Marshall stability and flow values along with density, air voids in total mix, voids in mineral aggregate, and voids filled with bitumen were determined to obtain OBC at different percentages of waste plastic, i.e., 4%, 6%, 8%, and 10% by weight of bitumen as additive. Results showed that the OBC for the plastic-modified asphalt mixtures at 4%, 6%, 8%, and 10% are 4.98, 5.44, 5.48, and 5.14, respectively. On the other hand, the controlled specimen’s shows better volumetric properties compared to plastic mixes. However, 4% additional of waste plastic indicated better stability than controlled specimen.

  16. Laboratory evaluation of resistance to moisture damage in asphalt mixtures

    Directory of Open Access Journals (Sweden)

    Ahmed Ebrahim Abu El-Maaty Behiry

    2013-09-01

    Full Text Available Moisture damage in asphalt mixtures refers to loss in strength and durability due to the presence of water. Egypt road network is showing severe deterioration such as raveling and stripping because the bond between aggregates and asphalt film is broken due to water intrusion. To minimize moisture damage, asphalt mixes are investigated to evaluate the effect of air voids, degree of saturation, media of attack and the conditioning period. Two medias of attack are considered and two anti-stripping additives are used (hydrated lime and Portland cement. The retained Marshall stability and tensile strength ratio are calculated to determine the resistance to moisture damage. The results showed that both lime and cement could increase Marshall stability, resilient modulus, tensile strength and resistance to moisture damage of mixtures especially at higher condition periods. Use of hydrated lime had better results than Portland cement.

  17. Deformation Parameters and Fatigue of the Recycled Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Šrámek Juraj

    2015-12-01

    Full Text Available The deformational properties of asphalt mixtures measured by dynamic methods and fatigue allow a design the road to suit the expected traffic load. Quality of mixtures is also expressed by the resistance to permanent deformation. Complex modulus of stiffness and fatigue can reliably characterize the proposed mixture of asphalt pavement. The complex modulus (E* measurement of asphalt mixtures are carried out in laboratory of Department of Construction Management at University of Žilina by two-point bending test method on trapezoid-shaped samples. Today, the fatigue is verified on trapezoid-shaped samples and is assessed by proportional strain at 1 million cycles (ε6. The test equipment and software is used to evaluate fatigue and deformation characteristics.

  18. Categories for Observing Language Arts Instruction (COLAI).

    Science.gov (United States)

    Benterud, Julianna G.

    Designed to study individual use of time spent in reading during regularly scheduled language arts instruction in a natural classroom setting, this coding sheet consists of nine categories: (1) engagement, (2) area of language arts, (3) instructional setting, (4) partner (teacher or pupil(s)), (5) source of content, (6) type of unit, (7) assigned…

  19. Language categories in Russian morphology

    OpenAIRE

    زهرایی زهرایی

    2009-01-01

    When studying Russian morphology, one can distinguish two categories. These categories are “grammatical” and “lexico-grammatical”. Grammatical categories can be specified through a series of grammatical features of words. Considering different criteria, Russian grammarians and linguists divide grammatical categories of their language into different types. In determining lexico-grammatical types, in addition to a series of grammatical features, they also consider a series of lexico-semantic fe...

  20. Rutting Prediction in Asphalt Pavement Based on Viscoelastic Theory

    Directory of Open Access Journals (Sweden)

    Nahi Mohammed Hadi

    2016-01-01

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

  1. State of the Art Study on Aging of Asphalt Mixtures and Use of Antioxidant Additives

    Directory of Open Access Journals (Sweden)

    Okan Sirin

    2018-01-01

    Full Text Available The detrimental effects of hardening in asphalt pavements were first recognized by pioneering pavement engineers in the 1900s and have been studied extensively during the last 70 years. This hardening process, referred to as asphalt aging, is generally defined as change in the rheological properties of asphalt binders/mixtures due to changes in chemical composition during construction and its service life period. Aging causes the asphalt material to stiffen and embrittle, which affects the durability and leads to a high potential for cracking. This paper presents the state of the art on asphalt and asphalt mixture aging and use of antioxidant additives to retard the aging. A picture of complex molecular structure of asphalt and its changes due to atmospheric condition and various protocols used to simulate aging in laboratory environment are also discussed. Emphasis is given on recent studies on simulation of aging of asphalt mixtures as there has been limited research on mixtures compared to the asphalt binder. Finally, this paper presents the application of antiaging techniques and its mechanism, use of various types of antioxidant additives to retard aging of asphalt and, hence, improve the performance of asphalt pavements.

  2. Effect of Material Composition and Environmental Condition on Thermal Characteristics of Conductive Asphalt Concrete

    Directory of Open Access Journals (Sweden)

    Pan Pan

    2017-02-01

    Full Text Available Conductive asphalt concrete with high thermal conductivity has been proposed to improve the solar energy collection and snow melting efficiencies of asphalt solar collector (ASC. This paper aims to provide some insight into choosing the basic materials for preparation of conductive asphalt concrete, as well as determining the evolution of thermal characteristics affected by environmental factors. The thermal properties of conductive asphalt concrete were studied by the Thermal Constants Analyzer. Experimental results showed that aggregate and conductive filler have a significant effect on the thermal properties of asphalt concrete, while the effect of asphalt binder was not evident due to its low proportion. Utilization of mineral aggregate and conductive filler with higher thermal conductivity is an efficient method to prepare conductive asphalt concrete. Moreover, change in thermal properties of asphalt concrete under different temperature and moisture conditions should be taken into account to determine the actual thermal properties of asphalt concrete. There was no noticeable difference in thermal properties of asphalt concrete before and after aging. Furthermore, freezing–thawing cycles strongly affect the thermal properties of conductive asphalt concrete, due to volume expansion and bonding degradation.

  3. Final environmental and regulatory assessment of using asphalt as a sealant in mine shafts

    International Nuclear Information System (INIS)

    1987-01-01

    This report discusses the properties of asphalt, the current regulatory status governing asphalt and future regulatory implications which may be pertinent in using asphalt as a waterproof shaft sealant. An understanding of the inherent organic composition of asphalt, an increase in the number of health and environmental research publications conducted on asphalt and an examination of the apparent trend of regulatory agencies toward more stringent environmental regulation governing the use of organic materials suggests asphalt could become regulated at a future time. This would only occur, however, if asphalt was found to conform to the present regulatory definitions of pollutants, contaminants or hazardous substances or if asphalt was included on a regulated substance list. In this regard, the study points out that asphalt contains very low levels of hazardous poly-nuclear aromatics (PNA's). These levels are significantly lower than the levels present in coal tars, a substance known to contain high levels of hazardous PNA's. Asphalt, however, has the inherent potential of producing higher concentrations of PNA's if the adverse condition of cracking should occur during the refinery production stage or on-site preparation of the asphalt. Also, unless existing control technology is applied, emission levels of sulfur dioxide, carbon monoxide, particulates and volatile organic carbons from the on-site preparation facilities could approach the permissible health standard levels of EPA. The study indicates, however, that available literature is limited on these issues

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

    Directory of Open Access Journals (Sweden)

    Jie Ji

    2017-02-01

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

  5. Automated titration method for use on blended asphalts

    Science.gov (United States)

    Pauli, Adam T [Cheyenne, WY; Robertson, Raymond E [Laramie, WY; Branthaver, Jan F [Chatham, IL; Schabron, John F [Laramie, WY

    2012-08-07

    A system for determining parameters and compatibility of a substance such as an asphalt or other petroleum substance uses titration to highly accurately determine one or more flocculation occurrences and is especially applicable to the determination or use of Heithaus parameters and optimal mixing of various asphalt stocks. In a preferred embodiment, automated titration in an oxygen gas exclusive system and further using spectrophotometric analysis (2-8) of solution turbidity is presented. A reversible titration technique enabling in-situ titration measurement of various solution concentrations is also presented.

  6. An investigation of waste foundry sand in asphalt concrete mixtures.

    Science.gov (United States)

    Bakis, Recep; Koyuncu, Hakan; Demirbas, Ayhan

    2006-06-01

    A laboratory study regarding the reuse of waste foundry sand in asphalt concrete production by replacing a certain portion of aggregate with WFS was undertaken. The results showed that replacement of 10% aggregates with waste foundry sand was found to be the most suitable for asphalt concrete mixtures. Furthermore, the chemical and physical properties of waste foundry sand were analysed in the laboratory to determine the potential effect on the environment. The results indicated that the investigated waste foundry sand did not significantly affect the environment around the deposition

  7. SYSTEM FOR CONTROLLING ELECTRIC DRIVE OF ASPHALT CONCRETE MIXING PLANT

    Directory of Open Access Journals (Sweden)

    A. S. Surmak

    2005-01-01

    Full Text Available It is proposed to evaluate quality of asphalt concrete mixture through definition of current component variable of a drive motor and measurement of its derivative sign. In order to carry out final determination of mixture uniformity a transducer on the basis of a nuclear magnetic resonance is applied. Block diagram of the system is presented and algorithm of its operation is given in the paper. In addition to improvement of the finished product quality the application of the system makes it possible to reduce bitumen consumption used for production of asphalt concrete.

  8. The Spontaneous Combustion of Railway Ties and Asphalt Shingles

    Science.gov (United States)

    Leslie, Geoffrey

    Many Low Carbon Fuels (LCFs) present unknown spontaneous combustion risks, which must be quantified before their use as fossil fuel replacements. Wood and coal spontaneous combustion is well understood; however, LCFs weather, and subsequent chemical changes could affect their spontaneous combustion properties. LCF spontaneous combustion could lead to accidental fires with possible loss of life, limb and property. The spontaneous combustion risks of two LCFs, discarded creosote-treated wooden railway ties and roofing asphalt shingles, were investigated with calorimetry and heat transfer experiments. Chemical changes due to weathering were studied with pyrolysis-Gas Chromatography/Mass Spectrometry (py-GC/MS). Creosote-treated wooden railway tie dust, roofing asphalt shingle particles, poplar wood pellets, and petroleum coke self-heating were studied with isothermal calorimetry. Railway tie dust and asphalt shingle heat transfer were characterized with a guarded hot plate. Petroleum coke self-heating was consistent with coal, while both poplar pellets and railway tie dust were found to be more reactive compared to oven test results of similar materials. The observed increase in reactivity was probably a result of significant moisture contenint in the pellet and railway tie dust. Critical conditions for spontaneous combustion were evaluated with the Frank-Kamenetskii parameter, assuming an ambient temperature of 40°C and constant moisture content. Kamenetskii calculations indicate that a 1.6 m cube of railway tie dust, or a 58 m cube of asphalt particles, would be unstable and combust. LCF chemistry may have been affected by weathering, which would cause chemical changes that affect their spontaneous combustion properties. Therefore, railway tie wood and roofing asphalt shingle chemistry were investigated by identifying products of 250° and 550°C pyrolysis with py-GC/MS. Railway tie wood pyrolyzates did not show signs of weathering; in contrast, asphalt pyrolysis

  9. Asphalt concrete modified by rubber crumbs in transport construction.

    Science.gov (United States)

    Duhovny, G. S.; Karpenko, AV

    2018-03-01

    High-temperature and low-temperature characteristics of the rubber-bitumen binder and rubber asphalt concrete based on it are researched. The determination method of binder’s low-temperature characteristics is offered. The estimation of binder’s and pavement’s stability against technological and operational aging is evaluated. Estimation of environmental and economic aspects of using rubber crumbs is made. The possibility of using rubber crumbs as modifier of organic binder for production of asphalt concrete on its base is justified.

  10. Effect of moisture and freeze-thaw on mechanical properties of CRM asphalt mixture

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nak-Seok; Cho, Kee-Ju [Kyonggi University, Suwon(Korea)

    2000-06-30

    This paper presents the experimental test results on moisture and freeze-thaw resistance of hot mix crumb rubber modified (CRM) asphalt concrete mixture. To compare the differences in mechanical properties of conventional and CRM asphalt concretes, various tests were conducted under different moisture conditions and freeze-thaw cycles. Marshall mix design was also performed to determine the optimum asphalt contents for the both asphalt concrete mixtures. Test results revealed that the moisture and freeze-thaw resistance of CRM asphalt mixture was superior to the conventional asphalt concrete. As a result, it is considered that the utilization of waste tires in asphalt pavements has the potential of minimizing the damage due to the moisture and freeze-thaw. (author). 9 refs., 4 tabs., 8 figs.

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

    Science.gov (United States)

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

    2016-04-01

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

  12. Progresses in irradiating SBS for road asphalt applications

    International Nuclear Information System (INIS)

    Li Linfan; Xie Leidong; Fu Haiying; Li Yintao; Yu Min; Sheng Kanglong; Yao Side

    2006-01-01

    Technical developments at SINAP to improve properties of SBS, a styrene-butadiene- styrene copolymer, for road asphalt applications are reviewed. In an attempt to better solve problems related to undesirable compatibility of SBS to asphalt components, we proposed a new method to modify the SBS molecular chains with ionizing radiations through radiation graft copolymerization and radiation crosslinking. Grafting a monomer with polar functional groups onto SBS molecules improves compatibility of SBS to polar components of asphalt, hence enhanced storage stability of the polymer modified asphalt (PMA), while crosslinks of SBS molecular chains endues increased physical properties to the PMA. Mechanisms of the radiation effects were studied with a series of SBS samples irradiated by 60 Co γ-rays or electron beams. The PMA and macadam-blended PMA samples showed higher performance than the control, i.e. SBS-modified asphalt by conventional approaches. The results can be summarized as follows. 1. The grafted SBS enhances thermostability of saturates and aromatics, the two asphalt components that exhibit the biggest SBS-swelling effect. The resins of asphalt, however, can hardly be absorbed by SBS, and the SBS is in a phase-separation status with the resins. Therefore, it is crucial to strengthen reactions between SBS and the resins to obtain stable and high quality PMA. 2. SBS molecular chains can be crosslinked with irradiation of a few tens of kGy. The crosslinking effect was evidenced by increased molecular weight of SBS and wider distribution of the molecular weight in GPC measurement of the irradiated SBS samples, and by decreased activation energy of viscosity in rheological measurement, in which the storage modulus G' increased and the loss modulus G' declined with increasing doses, indicating a larger elastic component and smaller viscous component in the irradiated SBS. Correspondingly, temperature sensitivity of the irradiated SBS reduced. Blended with SBS

  13. ADDITIVES FOR COLD ASPHALT-CONCRETE MADE FROM EMULSION-MINERAL MIXES

    Directory of Open Access Journals (Sweden)

    P. V. Vavilov

    2015-01-01

    Full Text Available The article considers the additives use for cold asphalt emulsion mixes. Urgency of the issue consists in the necessity of usage justification and regulation of additive for cold mixes properties adjustment. The article is represented as the general result of analysis of regulatory, literary and other sources related to additive using for CAEM.The main part of the article proposes and justifies the classification of CAEM additives according to their functional purpose (the main purpose of additive: increasing of strength, water resistance, durability, regulating curing and technological modifiers. Depending on the purpose the criteria of technical efficiency of additive using are presented. For each criteria provided the methods determining one or more quality indicators. The quality indicator changing is indicator of additive efficiency. There is provided the formula determining the efficiency of CAEM curing period reduction additives. As an example provided efficiency calculation and evaluation of additives for regulation (acceleration CAEM curing according to the previously published experimental data. The efficiency of curing regulating additives was determined according to the function of temporal changes of CAEM compressing strength and dynamic modulus of elasticity.The article provides the example list of materials that could be or currently used as additives for cold mixes. The conclusion states that proposed classification and criteria give base to purposive regulation of cold asphalt emulsion mixture compositions and their properties.

  14. Mechanistic and Economical Characteristics of Asphalt Rubber Mixtures

    Directory of Open Access Journals (Sweden)

    Mena I. Souliman

    2016-01-01

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

  15. Effect of Particulates Generated from Asphalt Production on the ...

    African Journals Online (AJOL)

    PROF HORSFALL

    in air, including dust, soot, dirt, smoke and liquid droplets. Particulate matter is of localized importance near roads, cement works, and other industrial areas. Apart from screening out sunlight, dust on leaf blocks stomata and lowers their conductants to Carbon iv oxide (Jitin and Manish, 2014). Asphalt, which is also referred ...

  16. The adoption of innovative asphalt equipment in road construction

    NARCIS (Netherlands)

    Habets, M.J.M.; Voordijk, Johannes T.; van der Sijde, Peter

    2011-01-01

    Purpose – The purpose of this paper is to provide insight into the adoption process of innovative asphalt equipment in road construction and how the level of knowledge as characterised by the level of education in the companies affects this process. The emphasis is on equipment used for transporting

  17. Steel slag in hot mix asphalt concrete : final report

    Science.gov (United States)

    2000-04-01

    In September 1994, steel slag test and control sections were constructed in Oregon to evaluate the use of steel slag in hot mix asphalt concrete (HMAC). This report covers the construction and five-year performance of a pavement constructed with 30% ...

  18. Using waste plastic bottles as additive for stone mastic asphalt

    International Nuclear Information System (INIS)

    Ahmadinia, Esmaeil; Zargar, Majid; Karim, Mohamed Rehan; Abdelaziz, Mahrez; Shafigh, Payam

    2011-01-01

    Highlights: → The PET increased the stiffness level of the mixture improving its resistance level against permanent deformation. → The effects of waste PET on Marshall Stability, air void and bulk specific gravity of the mixture are significant. → The appropriate amount of PET was found to be 6% by weight of bitumen. -- Abstract: Currently, polymer modified asphalt mixture is a relatively costly mixture for paving roads. One way to reduce the cost of such constructions and rendering them more convenient is by using inexpensive polymers, i.e. waste polymers. The main purpose of this research is to determine the effect of incorporating waste plastic bottles (Polyethylene Terephthalate (PET)) on the engineering properties of stone mastic asphalt (SMA) mixture. The volumetric and mechanical properties of asphalt mixes that include various percentages of PET (0%, 2%, 4%, 6%, 8% and 10%) were calculated and assessed with laboratory tests. The appropriate amount of PET was found to be 6% by weight of bitumen. The outcomes were statistically analysed and the determination of the significance at certain confidence limits was performed with the two factor variance analysis (ANOVA). Moreover, some studies conducted on polyethylene modified asphalt mixture have also been taken into consideration in this paper. The results show that the addition of PET has a significant positive effect on the properties of SMA and it can promote the re-use of waste material in industry in an environmentally friendly and economical way.

  19. Aggregate packing characteristics of good and poor performing asphalt mixes

    CSIR Research Space (South Africa)

    Denneman, E

    2007-07-01

    Full Text Available The aggregate structure of the compacted mix is a determining factor for the performance of Hot-Mix Asphalt (HMA). In this paper, the grading characteristics of good and poor performing HMA mixes are explored using the concepts of the Bailey method...

  20. LABORATORY EVALUATION OF COMPACTABILITY AND PERFORMANCE OF WARM MIX ASPHALT

    Directory of Open Access Journals (Sweden)

    Allex Eduardo Álvarez Lugo

    Full Text Available Warm mix asphalt (WMA is the term used to describe the set of technologies that allow fabrication of asphalt mixtures at lower temperatures than those specified for conventional hot mix asphalt (HMA. This temperature reduction leads to advantages, compared to construction of HMA, that include energy savings, reduced emissions, and safer working conditions. However, WMA is a relatively new technology and several aspects are still under evaluation. This paper assesses some of these aspects including laboratory compactability and its relation to mixture design, and performance of WMA (i.e., permanent deformation and cracking resistance fabricated with three WMA additives, namely Advera®, Sasobit®, and Evotherm®. Corresponding results showed better or equivalent laboratory compactability for the WMA, as compared to that of the HMA used as reference (or control-HMA, leading to smaller optimum asphalt contents selected based on a specific target density (i.e., 96%. In terms of performance, inclusion of the WMA additives led to decrease the mixture resistance to permanent deformation, although the mixture resistance to cracking can remain similar or even improve as compared to that of the control-HMA.

  1. Characterization of Brazilian asphalt using X-ray diffraction

    International Nuclear Information System (INIS)

    Cardoso, Edson R.; Pinto, Nivia G.V.; Almeida, Ana P.G.; Braz, Delson; Lopes, Ricardo T.; Barroso, Regina C.; Motta, Laura M.G.

    2007-01-01

    Asphalt is a sticky, black and highly viscous liquid or semi-solid that is presented in most crude petroleum and in some natural deposits. The X ray diffraction can give valuable information over the characteristics of a material. Thus, the X-ray diffraction (XRD) method was employed to investigate parameters that characterize and differentiate asphalt groups (Boscan, CAP20, CAP40, CAP50/60, CAP50/70 and CAP85/100). The scattering measurements were carried out in θ-2θ reflection geometry using a powder diffractometer Shimadzu XRD-6000 at the Nuclear Instrumentation Laboratory, Brazil. Scans were typically done from 8 deg to 28 deg every 0.05. The parameters analyzed were: FWHM, peak area, peak center, peak height, left half width and right half width. Thus, in this study, scattering profiles from different asphalt groups were carefully measured in order to establish characteristic signatures of these materials. The results indicate that by using three parameters (peak centroid, peak area and peak intensity) it is possible to characterize and differentiate the asphalt. (author)

  2. Field and laboratory investigation of warm mix asphalt in Texas.

    Science.gov (United States)

    2010-07-01

    During the first half of this research study, TxDOT had only placed 1000 tons of warm mix asphalt : (WMA) as part of a demonstration project. By the end of this three year study, TxDOT had placed more : than 1,000,000 tons of WMA and allowed its use ...

  3. Asphalt Concrete Mixtures: Requirements with regard to Life Cycle Assessment

    Directory of Open Access Journals (Sweden)

    Jan Mikolaj

    2015-01-01

    Full Text Available Design of asphalt concrete, required properties of constituent materials and their mixing ratios, is of tremendous significance and should be implemented with consideration given to the whole life cycle of those materials and the final construction. Conformity with requirements for long term performance of embedded materials is the general objective of the Life Cycle Assessment (LCA. Therefore, within the assessment, material properties need to be evaluated with consideration given to the whole service life—from the point of embedding in the construction until their disposal or recycling. The evaluation focuses on verification of conformity with criteria set for these materials and should guarantee serviceability and performance during their whole service life. Recycling and reuse of asphalt concrete should be preferred over disposal of the material. This paper presents methodology for LCA of asphalt concrete. It was created to ensure not only applicability of the materials in the initial stage, at the point of their embedding, but their suitability in terms of normatively prescribed service performance of the final construction. Methods described and results are presented in a case study for asphalt mixture AC 11; I design.

  4. Nondestructive evaluation of warm mix asphalt through resonant column testing.

    Science.gov (United States)

    2014-02-01

    Non-destructive testing has been used for decades to characterize engineering properties of hot-mix asphalt. Among such tests is the resonant column (RC) test, which is commonly used to characterize soil materials. The resonant column device at Penn ...

  5. The Acoustical Durability of Thin Noise Reducing Asphalt Layers

    Directory of Open Access Journals (Sweden)

    Cedric Vuye

    2016-05-01

    Full Text Available Within the context of the European Noise Directive, traffic noise action plans have been established. One of those actions is to deepen the knowledge about low noise roads, as they are considered the most cost-efficient measure for traffic noise abatement. Therefore, ten test sections were installed in May 2012 in Belgium, with the objective of integrating Thin noise-reducing Asphalt Layers (TAL in the Flemish road surface policy in a later stage. Eight test sections are paved with TAL with a thickness of a maximum of 30 mm and a maximum content of accessible voids of 18%. The other two sections consist of a Double-layer Porous Asphalt Concrete (DPAC and a Stone Mastic Asphalt (SMA-10 as a reference section. The acoustical quality of the asphalt surfaces has been monitored in time using Statistical Pass-By (SPB and Close-ProXimity (CPX measurements up to 34 months after construction. Texture measurements performed with a laser profilometer are linked to the noise measurement results. Very promising initial noise reductions were found, up to 6 dB(A, but higher than expected acoustic deterioration rates and the presence of raveling led to noise reductions of a max. of 1 dB(A after almost three years. It is shown that the construction process itself has a large influence on the acoustical quality over time.

  6. Effect of Waste Plastic as Bitumen Modified in Asphalt Mixture

    Directory of Open Access Journals (Sweden)

    Abdullah Mohd Ezree

    2017-01-01

    Full Text Available The objectives of this study are to investigate the engineering properties of the asphalt mixtures containing waste plastic at different percentages i.e. 4%, 6%, 8%, and 10% by weight of bitumen. The experimental tests performed in the study were stability, tensile strength, resilient modulus and dynamic creep test. Results showed that the mixture with 4% plastic has the highest stability (184kN. However, the stability slightly decreases with the increase of plastic additive. On the other hand, the highest tensile strength among the modified asphaltic concrete is 1049kPa (8% plastic added. The modified asphalt mixture with 8% plastic has the highest resilient modulus, which is 3422 MPa (25°C and 494Mpa (40°C. Where the highest creep modulus recorded is 73.30Mpa at 8% plastic added. It can be concluded that the addition of 8% plastic gave the highest value properties of asphalt mixture. Finally, it can be said that 8% plastic is the optimum value adding.

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

    Science.gov (United States)

    Brown, Arthur

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

  8. Thermal segregation of asphalt material in road repair

    Directory of Open Access Journals (Sweden)

    Juliana Byzyka

    2017-08-01

    Full Text Available This paper presents results from a field study of asphaltic pavement patching operations performed by three different contractors working in a total of ten sites. It forms part of an ongoing research programme towards improving the performance of pothole repairs. Thermal imaging technology was used to record temperatures of the patching material throughout the entire exercise, from the stage of material collection, through transportation to repair site, patch forming, and compaction. Practical complications occurring during patch repairs were also identified. It was found that depending on the weather conditions, duration of the travel and poor insulation of the transported hot asphalt mix, its temperature can drop as high as 116.6 °C over the period that the reinstatement team travel to the site and prepare the patch. This impacting is on the durability and performance of the executed repairs. Cold spots on the asphalt mat and temperature differentials between the new hot-fill asphalt mix and existing pavement were also identified as poorly compacted areas that were prone to premature failure. For example, over the five-minute period, the temperature at one point reduced by 33% whereas the temperatures of nearby areas decreased by 65% and 71%. A return visit to the repair sites, three months later, revealed that locations where thermal segregation was noted, during the patching operation, had failed prematurely.

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

    NARCIS (Netherlands)

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

    2003-01-01

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

  10. Direct Tensile Test to Assess Healing in Asphalt

    NARCIS (Netherlands)

    Leegwater, G.A.; Scarpas, Athanasios; Erkens, Sandra

    2016-01-01

    Asphalt concrete has the advantageous ability to heal. During rest
    periods, damage present In the material is restored to a certain extent.
    Healing of the material can be observed in iis regaining of strength
    and stiffness after rest periods. In this paper, a new test method is

  11. Direct tensile test to assess healing in asphalt

    NARCIS (Netherlands)

    Leegwater, G.A.; Scarpas, T.; Erkens, S.

    2016-01-01

    Asphalt concrete has the advantageous ability to heal. During rest periods, damage present in the material is restored to a certain extent. Healing of the material can be observed in its regaining of strength and stiffness after rest periods. In this paper, a new test method is presented. It was

  12. Improvement of the asphalt-waste products in leachability

    International Nuclear Information System (INIS)

    Matsuzuru, Hideo; Fojiri, Shigeru; Moriyama, Noboru

    1980-05-01

    To improve in leachability of the asphalt products containing evaporator residue from BWR, a method of reducing the swelling of asphalt products, which is a major cause for increasing the leachability, has been developed. Leachability of the resultant asphalt products was examined by IAEA's method. The reduction of swelling is achieved successfully by addition of an equivalent quantity of calcium chloride to the sodium sulfate contained in the residue; the sodium sulfate is converted to calcium sulfate and sodium chloride. The specimen (Asphalt/Na 2 SO 4 : 0.5) prepared by this improved method shows little swelling when immersed in water. The specimen without addition of calcium chloride gives a cumulative leaching fraction of about 0.65 for 137 Cs and 0.20 for 60 Co in 30 days. On the contrary, the corresponding values in about 100 days of the specimen with calcium chloride added are 5 x 10 -4 and 1 x 10 -4 for 137 Cs and 60 Co, respectively. These results indicate that the method is promising for reducing the leachability. Coating of the specimen surface with a fresh bitumen further reduces the leachability to a negligibly small value. (author)

  13. Investigation of Induction Heating in Asphalt Mortar: Numerical Approach

    NARCIS (Netherlands)

    Apostolidis, P.; Liu, X.; Scarpas, Athanasios; van de Ven, M.F.C.; van Bochove, G

    2016-01-01

    The research reported in this paper focuses on utilization of advanced finite-element analyses (COMSOL) for the design and assessment of the induction heating capacity of asphalt mortar by adding electrically conductive additives (e.g., steel fibers), and to understand the factors that influence the

  14. Investigation of asphalt core-plinth connection in embankment dams

    Directory of Open Access Journals (Sweden)

    Weibiao Wang

    2017-12-01

    Full Text Available The asphalt core itself is a no-joint water barrier in embankment dams and is connected to the concrete plinth on the bottom of the core. A reliable asphalt core-plinth connection is crucial and must remain watertight when the core deforms due to deformations in the embankment and foundation and due to reservoir water pressure. A large number of tension tests were conducted to determine the best ratios, joint thickness and suitable additives for the sandy asphalt mastic (SAM mix used for the connection. With the ratios of bitumen to filler to sand of 20%:35%:45% and by adding 4% SBS in the bitumen, one got a very suitable composition for the asphalt core-plinth connection in tensile conditions. Model tests were conducted to study the connection behavior when subjected to large shear displacements and high water pressure. The joint model test results indicate that the plane-surface plinth, curved-surface plinth, and plinth with or without copper water-stop showed no significant difference for the connection in the joint shear behavior. However, plinth with copper water-stop is suggested to enhance its tensile and shear behavior.

  15. Effect of the weather in the aging of asphalts by XRD

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Edson da R.; Braz, Delson; Lopes, Ricardo T., E-mail: ecardoso@lin.ufrj.b [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Motta, Laura M.G. da, E-mail: Laura@coc.ufrj.b [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Construcao Civil/Geotecnia; Barroso, Regina C., E-mail: cely@uerj.b [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Fisica

    2009-07-01

    Asphalt is a sticky, black and highly viscous liquid or semi-solid that is presented in most crude petroleum and in some natural deposits. As is well known, asphalt has been the preferential choice in pavement construction since excellent utility of pavement, however, as other organic substances, it is also subjected to aging phenomena evolving with time. Asphalt aging is one of the principal factors causing deterioration of asphalt pavements. The photodegradation of asphalts must be considered in the study of the performance of asphalt pavement, especially in geographical regions where high solar radiation intensity occurs. It has an important influence in asphalt aging in tropical places as Brazil. Many methods have been applied to simulate aging of bitumen. It was just a simulation but not real aging asphalt. In this study we submitted the asphalt to the weather as sun and rain. Periodically, during 430 days, the XRD profiles were done and the results analyzed. The scattering measurements were carried out in 0-20 reflection geometry using a powder diffractometer Shimadzu XRD-6000. Scans were typically done from 8 deg to 28 deg every 0.05 deg. The parameters FWHM and peak centroid were analyzed. From 0 until 180 days the aging was faster. The peaks were marked and analyzed with the pass of time. The crystallinity of asphalt increase with weather exposition. Some angles of profiles changed the position indicating change of atomics plans. (author)

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

    Directory of Open Access Journals (Sweden)

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

    2014-04-01

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

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

    Directory of Open Access Journals (Sweden)

    Shakir.A.Al-Mishhadani

    2014-02-01

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

  18. Performance Evaluation of Hot Mix Asphalt with Different Proportions of RAP Content

    Directory of Open Access Journals (Sweden)

    Kamil Arshad Ahmad

    2018-01-01

    Full Text Available Reclaimed Asphalt Pavement (RAP is old asphalt pavement that has been removed from a road by milling or full depth removal. The use of RAP in hot mix asphalt (HMA eliminates the need to dispose old asphalt pavements and conserves asphalt binders and aggregates, resulting in significant cost savings and benefits to society. This paper presents a study on HMA with different RAP proportions carried out to evaluate the volumetric properties and performance of asphalt mixes containing different proportions of RAP. Marshall Mix Design Method was used to produce control mix (0% RAP and asphalt mixes containing 15% RAP, 25% RAP and 35% RAP in accordance with Specifications for Road Works of Public Works Department, Malaysia for AC14 dense graded asphalt gradation. Volumetric analysis was performed to ensure that the result is compliance with specification requirements. The resilient modulus test was performed to measure the stiffness of the mixes while the Modified Lottman test was conducted to evaluate the moisture susceptibility of these mixes. The Hamburg wheel tracking test was used to evaluate the rutting performance of these mixes. The results obtained showed that there were no substantial difference in Marshall Properties, moisture susceptibility, resilient modulus and rutting resistance between asphalt mixes with RAP and the control mix. The test results indicated that recycled mixes performed as good as the performance of conventional HMA in terms of moisture susceptibility and resilient modulus. It is recommended that further research be carried out for asphalt mixes containing more than 35% RAP material.

  19. Effect of the weather in the aging of asphalts by XRD

    International Nuclear Information System (INIS)

    Cardoso, Edson da R.; Braz, Delson; Lopes, Ricardo T.; Motta, Laura M.G. da; Barroso, Regina C.

    2009-01-01

    Asphalt is a sticky, black and highly viscous liquid or semi-solid that is presented in most crude petroleum and in some natural deposits. As is well known, asphalt has been the preferential choice in pavement construction since excellent utility of pavement, however, as other organic substances, it is also subjected to aging phenomena evolving with time. Asphalt aging is one of the principal factors causing deterioration of asphalt pavements. The photodegradation of asphalts must be considered in the study of the performance of asphalt pavement, especially in geographical regions where high solar radiation intensity occurs. It has an important influence in asphalt aging in tropical places as Brazil. Many methods have been applied to simulate aging of bitumen. It was just a simulation but not real aging asphalt. In this study we submitted the asphalt to the weather as sun and rain. Periodically, during 430 days, the XRD profiles were done and the results analyzed. The scattering measurements were carried out in 0-20 reflection geometry using a powder diffractometer Shimadzu XRD-6000. Scans were typically done from 8 deg to 28 deg every 0.05 deg. The parameters FWHM and peak centroid were analyzed. From 0 until 180 days the aging was faster. The peaks were marked and analyzed with the pass of time. The crystallinity of asphalt increase with weather exposition. Some angles of profiles changed the position indicating change of atomics plans. (author)

  20. Performance Evaluation of Hot Mix Asphalt with Different Proportions of RAP Content

    Science.gov (United States)

    Kamil Arshad, Ahmad; Awang, Haryati; Shaffie, Ekarizan; Hashim, Wardati; Rahman, Zanariah Abd

    2018-03-01

    Reclaimed Asphalt Pavement (RAP) is old asphalt pavement that has been removed from a road by milling or full depth removal. The use of RAP in hot mix asphalt (HMA) eliminates the need to dispose old asphalt pavements and conserves asphalt binders and aggregates, resulting in significant cost savings and benefits to society. This paper presents a study on HMA with different RAP proportions carried out to evaluate the volumetric properties and performance of asphalt mixes containing different proportions of RAP. Marshall Mix Design Method was used to produce control mix (0% RAP) and asphalt mixes containing 15% RAP, 25% RAP and 35% RAP in accordance with Specifications for Road Works of Public Works Department, Malaysia for AC14 dense graded asphalt gradation. Volumetric analysis was performed to ensure that the result is compliance with specification requirements. The resilient modulus test was performed to measure the stiffness of the mixes while the Modified Lottman test was conducted to evaluate the moisture susceptibility of these mixes. The Hamburg wheel tracking test was used to evaluate the rutting performance of these mixes. The results obtained showed that there were no substantial difference in Marshall Properties, moisture susceptibility, resilient modulus and rutting resistance between asphalt mixes with RAP and the control mix. The test results indicated that recycled mixes performed as good as the performance of conventional HMA in terms of moisture susceptibility and resilient modulus. It is recommended that further research be carried out for asphalt mixes containing more than 35% RAP material.

  1. Evaluation of permanent deformation and durability of epoxidized natural rubber modified asphalt mix

    Science.gov (United States)

    Al-Mansob, Ramez A.; Ismail, Amiruddin; Rahmat, Riza Atiq O. K.; Nazri Borhan, Muhamad; Alsharef, Jamal M. A.; Albrka, Shaban Ismael; Rehan Karim, Mohamed

    2017-09-01

    The road distresses have caused too much in maintenance cost. However, better understandings of the behaviours and properties of asphalt, couples with greater development in technology, have allowed paving technologists to examine the benefits of introducing additives and modifiers. As a result, modifiers such as polymers are the most popular modifiers used to improve the performance of asphalt mix. This study was conducted to investigate the use of epoxidized natural rubber (ENR) to be mixed with asphalt mix. Tests were conducted to investigate the performance characteristics of ENR-asphalt mixes, where the mixes were prepared according to the wet process. Mechanical testing on the ENR-asphalt mixes have demonstrated that the asphalt mix permanent deformation performance at high temperature was found to be improved compared to the base mixes. However, the durability studies have indicated that ENR-asphalt mixes are slightly susceptible with the presence of moisture. The durability of the ENR-asphalt mixes were found to be enhanced in term of permanent deformation at high and intermediate temperatures compared to the base asphalt mixes. As conclusion, asphalt pavement performance can be enhanced by using ENR as modifier to face the major road distresses.

  2. Design and Properties of Asphalt Concrete Mixtures Using Renewable Bioasphalt Binder

    Science.gov (United States)

    Setyawan, A.; Djumari; Irfansyah, P. A.; Shidiq, A. M.; Wibisono, I. S.; Fauzy, M. N.; Hadi, F. N.

    2017-02-01

    The needs of petroleum asphalt as materials for pavement is very large, while the petroleum classified as natural resources that cannot be renewable. As a result of petroleum dwindling and prices tend to be more expensive. So that requiring other alternative materials as a substitute for conventional asphalt derived from biomass or often called bioasphalt. This study aims to know the volumetric and Marshall characteristics on Asphalt Cement ( AC ) using the Damar asphalt modification to substitute 60/70 penetration asphalt as a binder. The volumetric and Marshall characteristic are porosity, density, flow, stability, and Marshall quotient. The characteristic of asphalt concrete at optimum bitumen content are compared to the conditions from highway agency 1987 and the general specification of asphalt concrete Bina Marga 2010 the third revision. The research uses experimental method in the laboratory with the samples made using the dasphalt modification as binder and incorporating the aggregate gradation no. VII SNI 03-1737-1989. The research is using 15 samples divided into 5 contents of damar asphalt, they are 5%, 5,5%, 6%, 6,5%, dan 7%. Tests carried out using Marshall test equipment to get the value of flow and stability and then be searched the value of optimum damar asphalt content. The result of asphalt concrete analysis using dasphalt modification as binder gives the value of optimum dasphalt content at 5,242%. The most characteristics already met the requirements and specifications.

  3. Influence of the Microwave Heating Time on the Self-Healing Properties of Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Jose Norambuena-Contreras

    2017-10-01

    Full Text Available This paper aims to evaluate the influence of the microwave heating time on the self-healing properties of fibre-reinforced asphalt mixtures. To this purpose, self-healing properties of dense asphalt mixtures with four different percentages of steel wool fibres were evaluated as the three-point bending strength before and after healing via microwave heating at four different heating times. Furthermore, the thermal behaviour of asphalt mixtures during microwave heating was also evaluated. With the aim of quantifying the efficiency of the repair process, ten damage-healing cycles were done in the test samples. In addition, self-healing results were compared with the fibre spatial distribution inside asphalt samples evaluated by CT-scans. Crack-size change on asphalt samples during healing cycles was also evaluated through optical microscopy. It was found that the heating time is the most influential variable on the healing level reached by the asphalt mixtures tested by microwave radiation. CT-Scans results proved that fibre spatial distribution into the asphalt mixtures play an important role in the asphalt healing level. Finally, it was concluded that 40 s was the optimum heating time to reach the highest healing levels with the lowest damage on the asphalt samples, and that heating times over 30 s can seal the cracks, thus achieving the self-healing of asphalt mixtures via microwave heating.

  4. sources

    Directory of Open Access Journals (Sweden)

    Shu-Yin Chiang

    2002-01-01

    Full Text Available In this paper, we study the simplified models of the ATM (Asynchronous Transfer Mode multiplexer network with Bernoulli random traffic sources. Based on the model, the performance measures are analyzed by the different output service schemes.

  5. Effect of new type of synthetic waxes on reduced production and compaction temperature of asphalt mixture with reclaimed asphalt

    Science.gov (United States)

    Valentová, Tereza; Benešová, Lucie; Mastný, Jan; Valentin, Jan

    2017-09-01

    Lower mixing and paving temperatures of asphalt mixtures, which are an important issue in recent years, with respect to increased energy demand of civil engineering structures during their processing, allow reduction of this demand and result in minimized greenhouse gas production. In present time, there are many possibilities how to achieve reduction of production temperature during the mixing and paving of an asphalt mixture. The existing solutions distinguish in target operating temperature behaviour which has to be achieved in terms of good workability. This paper is focused on technical solutions based on use of new types of selected synthetic and bio-based waxes. In case of bio-based additive sugar cane wax was used, which is free of paraffins and is reclaimed as waste product during processing of sugar cane. The used waxes are added to bituminous binder in form of free-flowing granules or fine-grained powder. Synthetic waxes are represented by new series of Fischer-Tropsch wax in form of fine granules as well as by polyethylene waxes in form of fine-grained powder or granules. Those waxes were used to modify a standard paving grade bitumen dosed into asphalt mixture of ACsurf type containing up to 30 % of reclaimed asphalt (RA).

  6. Subject categories and scope descriptions

    International Nuclear Information System (INIS)

    2002-01-01

    This document is one in a series of publications known as the ETDE/INIS Joint Reference Series. It defines the subject categories and provides the scope descriptions to be used for categorization of the nuclear literature for the preparation of INIS and ETDE input by national and regional centres. Together with the other volumes of the INIS Reference Series it defines the rules, standards and practices and provides the authorities to be used in the International Nuclear Information System and ETDE. A complete list of the volumes published in the INIS Reference Series may be found on the inside front cover of this publication. This INIS/ETDE Reference Series document is intended to serve two purposes: to define the subject scope of the International Nuclear Information System (INIS) and the Energy Technology Data Exchange (ETDE) and to define the subject classification scheme of INIS and ETDE. It is thus the guide to the inputting centres in determining which items of literature should be reported, and in determining where the full bibliographic entry and abstract of each item should be included in INIS or ETDE database. Each category is identified by a category code consisting of three alphanumeric characters. A scope description is given for each subject category. The scope of INIS is the sum of the scopes of all the categories. With most categories cross references are provided to other categories where appropriate. Cross references should be of assistance in finding the appropriate category; in fact, by indicating topics that are excluded from the category in question, the cross references help to clarify and define the scope of the category to which they are appended. A Subject Index is included as an aid to subject classifiers, but it is only an aid and not a means for subject classification. It facilitates the use of this document, but is no substitute for the description of the scope of the subject categories

  7. Radiation protection in category III large gamma irradiators

    International Nuclear Information System (INIS)

    Costa, Neivaldo; Furlan, Gilberto Ribeiro; Itepan, Natanael Marcio

    2011-01-01

    This article discusses the advantages of category III large gamma irradiator compared to the others, with emphasis on aspects of radiological protection, in the industrial sector. This category is a kind of irradiators almost unknown to the regulators authorities and the industrial community, despite its simple construction and greater radiation safety intrinsic to the model, able to maintain an efficiency of productivity comparable to those of category IV. Worldwide, there are installed more than 200 category IV irradiators and there is none of a category III irradiator in operation. In a category III gamma irradiator, the source remains fixed in the bottom of the tank, always shielded by water, negating the exposition risk. Taking into account the benefits in relation to radiation safety, the category III large irradiators are highly recommended for industrial, commercial purposes or scientific research. (author)

  8. How categories come to matter

    DEFF Research Database (Denmark)

    Leahu, Lucian; Cohn, Marisa; March, Wendy

    2013-01-01

    In a study of users' interactions with Siri, the iPhone personal assistant application, we noticed the emergence of overlaps and blurrings between explanatory categories such as "human" and "machine". We found that users work to purify these categories, thus resolving the tensions related to the ...... initial data analysis, due to our own forms of latent purification, and outline the particular analytic techniques that helped lead to this discovery. We thus provide an illustrative case of how categories come to matter in HCI research and design.......In a study of users' interactions with Siri, the iPhone personal assistant application, we noticed the emergence of overlaps and blurrings between explanatory categories such as "human" and "machine". We found that users work to purify these categories, thus resolving the tensions related...

  9. The composition of category conjunctions.

    Science.gov (United States)

    Hutter, Russell R C; Crisp, Richard J

    2005-05-01

    In three experiments, the authors investigated the impression formation process resulting from the perception of familiar or unfamiliar social category combinations. In Experiment 1, participants were asked to generate attributes associated with either a familiar or unfamiliar social category conjunction. Compared to familiar combinations, the authors found that when the conjunction was unfamiliar, participants formed their impression less from the individual constituent categories and relatively more from novel emergent attributes. In Experiment 2, the authors replicated this effect using alternative experimental materials. In Experiment 3, the effect generalized to additional (orthogonally combined) gender and occupation categories. The implications of these findings for understanding the processes involved in the conjunction of social categories, and the formation of new stereotypes, are discussed.

  10. Research on the characteristics of temperature field of asphalt pavement in seasonal frozen region

    International Nuclear Information System (INIS)

    Qiao, Jiangang; Liu, Weizheng

    2014-01-01

    The characteristics of climate in seasonal frozen area are low temperature and a large range of temperature variation between day and night in winter. These characteristics often lead to problems of asphalt pavement, especially transverse cracks. To reduce the problems of asphalt pavement, it is necessary to examine the distribution of the temperature range of asphalt pavement. A three-dimensional finite element model was used, taking the SMA asphalt pavement as an example with solid70 and plane55 unit features of ANSYS software. It can obtain the relationship between temperature gradient and time and the relationship between temperature gradient and depth. In addition, a function relation model of stress and time was also established. It can provide a theoretical basis for the prevention and treatment of problems of asphalt pavement in seasonal frozen area. Moreover, it has an important significance for improving asphalt pavement design

  11. Decision of National and Provincial Highway Asphalt Pavement Structure Based on Value Engineering

    Directory of Open Access Journals (Sweden)

    Yingwei Ren

    2014-01-01

    Full Text Available It is important that decision of asphalt pavement structure requires overall considerations of the performance and financial investment. To have asphalt pavement structure fulfilling good reliability, the asphalt pavement structure decision was researched based on value engineering theory. According to the national and provincial highway investigation data in Shandong Province during the last decade, the asphalt pavement performance attenuation rules of traffic levels and asphalt layer thicknesses were developed, and then the road performance evaluation method was presented. In addition, the initial investments, the costs of road maintenance, and middle-scale repair in a period were analyzed. For the light traffic and medium traffic example, using the value engineering method, the pavement performance and costs of which thickness varies from 6 cm to 10 cm were calculated and compared. It was concluded that value engineering was an effective method in deciding the asphalt pavement structure.

  12. The effect of long-term oxidation on the rheological properties of polymer modified asphalts

    Energy Technology Data Exchange (ETDEWEB)

    Yonghong Ruan; Richard R. Davison; Charles J. Glover [Texas A & M University, College Station, TX (United States). Department of Chemical Engineering

    2003-10-01

    The effect of long-term aging on rheological properties of polymer modified asphalt binders was studied. Modifiers included diblock poly(styrene-b-butadiene) rubber, triblock poly(styrene-b-butadiene-b-styrene), and tire rubber. Asphalt aging was carried out either at 60{sup o}C in a controlled environmental room or at 100{sup o}C in a pressure aging vessel (AASHTO Provisional Standards, 1993). Both dynamic shear properties and extensional properties were investigated. Polymer modification resulted in increased asphalt complex modulus at high temperatures, decreased asphalt complex modulus at low temperatures, broadened relaxation spectra, and improved ductility. Oxidative aging decreased asphalt temperature susceptibility, damaged the polymer network in binders, further broadened the relaxation spectrum, and diminished polymer effectiveness in improving asphalt ductility. 27 refs., 8 figs., 3 tabs.

  13. Mechanical Property and Analysis of Asphalt Components Based on Molecular Dynamics Simulation

    Directory of Open Access Journals (Sweden)

    Rui Li

    2017-01-01

    Full Text Available The asphalt-aggregate interface interaction plays a significant role in the overall performances of asphalt mixture. In order to analyze the chemical constitution of asphalt effects on the asphalt-aggregate interaction, the average structure C64H52S2 is selected to represent the asphalt, and the colloid, saturated phenol, and asphaltene are selected to represent the major constitutions in asphalt. The molecular models are established for the three compositions, respectively, and the Molecular Dynamics (MD simulation was conducted for the three kinds of asphaltene-aggregate system at different presses. Comparing the E value of Young modulus of these three polymers, the maximum modulus value of asphaltene was 2.80 GPa, the modulus value of colloid was secondary, and the minimum modulus of saturated phenol was 0.52 GPa. This result corresponds to conventional understanding.

  14. Leachability of Cr(VI) and other metals from asphalt composites with addition of filter dust.

    Science.gov (United States)

    Vahcic, Mitja; Milacic, Radmila; Mladenovic, Ana; Murko, Simona; Zuliani, Tea; Zupancic, Marija; Scancar, Janez

    2008-12-01

    The potential use of filter dust in asphalt composites for road construction was investigated. Filter dust contains high concentrations of metals, of which Cr(VI) and Pb are leached with water. Compact and ground asphalt composites with addition of 2% of filter dust by mass were studied. In order to evaluate their environmental impact, leachability tests were performed using water and salt water as leaching agents. The concentrations of Cr(VI) and Pb were determined in leachates over a time period of 182 days. The results indicated that Pb was not leached with leaching agents from asphalt composites. Cr(VI) was also not leached with leaching agents from compact asphalt composites. However, in ground asphalt composites, Cr(VI) was leached with water in concentrations up to 220 microg L(-1) and in salt water up to 150 microg L(-1). From the physico-mechanical and environmental aspects, filter dust can be used as a component in asphalt mixtures.

  15. Hanford protective barriers program: Status of asphalt barrier studies - FY 1989

    International Nuclear Information System (INIS)

    Freeman, H.D.; Gee, G.W.

    1989-11-01

    The Hanford Protective Barrier Program is evaluating alternate barriers to provide a means of meeting stringent water infiltration requirements. One type of alternate barrier being considered is an asphalt-based layer, 1.3 to 15 cm thick. Evaluations of these barriers were initiated in FY 1988, and, based on laboratory studies, two asphalt formulations were selected for further testing in small-tube lysimeters: a hot rubberized asphalt and an admixture of cationic asphalt emulsion and concrete sand containing 24 wt% residual asphalt. Eight lysimeters containing asphalt seals were installed as part of the Small Tube Lysimeter Test Facility on the Hanford Site. Two control lysimeters containing Hanford sand with a surface gravel treatment were also installed for comparison. 5 refs., 13 figs., 1 tab

  16. Performance Evaluation and Improving Mechanisms of Diatomite-Modified Asphalt Mixture.

    Science.gov (United States)

    Yang, Chao; Xie, Jun; Zhou, Xiaojun; Liu, Quantao; Pang, Ling

    2018-04-27

    Diatomite is an inorganic natural resource in large reserve. This study consists of two phases to evaluate the effects of diatomite on asphalt mixtures. In the first phase, we characterized the diatomite in terms of mineralogical properties, chemical compositions, particle size distribution, mesoporous distribution, morphology, and IR spectra. In the second phase, road performances, referring to the permanent deformation, crack, fatigue, and moisture resistance, of asphalt mixtures with diatomite were investigated. The characterization of diatomite exhibits that it is a porous material with high SiO₂ content and large specific surface area. It contributes to asphalt absorption and therefore leads to bonding enhancement between asphalt and aggregate. However, physical absorption instead of chemical reaction occurs according to the results of FTIR. The resistance of asphalt mixtures with diatomite to permanent deformation and moisture are superior to those of the control mixtures. But, the addition of diatomite does not help to improve the crack and fatigue resistance of asphalt mixture.

  17. SGC Tests for Influence of Material Composition on Compaction Characteristic of Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Qun Chen

    2013-01-01

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

  18. Using ESEM to analyze the microscopic property of basalt fiber reinforced asphalt concrete

    Directory of Open Access Journals (Sweden)

    Chunmei Gao

    2018-07-01

    Full Text Available The basalt fiber staggered distribution in the asphalt concrete matrix and the bonding situation between asphalt are analyzed by images collected using field emission environmental scanning electron microscope (ESEM test equipment. The results show that bonding of the fiber and the asphalt binder is very good and there is a strong binding force of chemical bonding connections between the two; the lipophilicity of basalt fiber is very good, the wrapped cover ability of asphalt for fiber is very strong; basalt fiber forms the local space network structure in the asphalt concrete matrix, effectively overcome the relative slip between the particles, connect the damaged parts into a whole; basalt fiber across internal micropores, and the internal defects in material can be remedied. At the same time, crack resistance mechanism of the fiber to internal micro cracks is qualitatively explained according to the magnitude of the stress intensity factor Kf. Keywords: Road engineering, Asphalt concrete, Basalt fiber, Microscopic analysis

  19. Rutting Performance of Cold-Applied Asphalt Repair Materials for Airfield Pavements

    Science.gov (United States)

    2017-06-23

    this study. Cold mix asphalt materials, further denoted cold mixes , were selected to reasonably represent available products on the market and were...pavement repair, primarily because of the small quantities involved and/or the unavailability of hot- mixed asphalt. These cold-applied mixtures have...poorer rutting resistance than hot mix asphalt because additives, often solvent, are required to provide adequate workability for them to be placed

  20. Mechanical Properties of Hot Mix Crumb Rubber Modified Asphalt Concrete Using Waste Tire

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nak Seok; Lee, Woo Yeol [Kyonggi University, Suwon (Korea)

    1998-06-30

    Wheel tracking and ravelling tests were conducted on the hot mix crumb rubber modified asphalt concrete using waste tire to evaluate the mechanical properties in comparison with conventional asphalt concrete. According to the test results, the modified product was superior to the conventional one by 50% in the resistance of permanent deformation and by 15% in the resistance of durability. The experimental results should recommend that the waste tire is positively recycled for asphalt concrete. (author). 11 refs., 6 tabs., 2 figs.

  1. Evaluation of factors that affect rutting resistance of asphalt mixes by orthogonal experiment design

    Directory of Open Access Journals (Sweden)

    Guilian Zou

    2017-05-01

    Full Text Available Rutting has been one of the major distresses observed on asphalt pavement in China, due to increasing traffic volume, heavy axle load, continuous hot weather, etc., especially in long-steep-slope section, bus stops, etc. Many factors would affect rutting resistance of asphalt pavement, including material properties, climatic condition, traffic volumes, speed, and axle types, and construction quality.The orthogonal experimental design method was used in this study to reduce the number of tests required, without comprising the validity of the test results. The testing variables and their levels were selected according to investigations and field test results. Effects of various factors on asphalt pavement rutting performance were evaluated, including the asphalt binders, mixture type (aggregate gradation, axle load, vehicle speed and temperature.In this study, the wheel tracking test was used to evaluate rutting performance, as represented by the parameter Dynamic Stability (DS, of the various asphalt mixes. Test results were analyzed using range analysis and analysis of variance (ANOVA. All four factors evaluated in this study had significant effects on pavement rutting performance. The ranking of the significance was asphalt mixture type, temperature, loading frequency, and tire-pavement contact pressure. Asphalt mixture type was the most important factor that affects rutting resistance. Within the asphalt mixtures, asphalt binder had significant effects on rutting performance of mixes more than aggregate gradation. Rutting resistance of SBS modified asphalt mixes was significantly better than neat asphalt mixes, and skeleton dense structure mixes were better than suspended dense structure mixes. Keywords: Asphalt mixes, Rutting resistance, Effect factor, Orthogonal experiment design

  2. Design Method for Proportion of Cement-Foamed Asphalt Cold Recycled Mixture

    OpenAIRE

    Li Junxiao; Fu Wei; Zang Hechao

    2018-01-01

    Through foaming experiment of Zhongtai AH-70 asphalt, the best foaming temperature water consumption and influence factors of foamed asphalt’s foaming features are determined; By designing the proportion of foamed asphalt cold in-place recycled mixture combined with the water stability experiment, for this mixture the best foamed asphalt addition is 3%, and proportion of the mixture is RAP: fine aggregate: cement=75:23:2. Using SEM technology, the mechanism of increasing on the intensity of f...

  3. Performance on Water Stability of Cement-Foamed Asphalt Cold Recycled Mixture

    OpenAIRE

    Li Junxiao; Fu Wei; Zang Hechao

    2018-01-01

    Through designing the mixture proportion of foamed asphalt cold in-place recycled mixture combined with the water stability experiment, it shows that the addition of cement can obviously improve foamed asphalt mixture’s water stability and the best cement admixture is between 1% ~ 2%; Using digital imaging microscope and SEM technology, the mechanism of increasing on the intensity of foamed asphalt mixture resulted by adding cement was analyzed. It revealed that the cement hydration products ...

  4. Removal of contaminated asphalt layers by using heat generating powder metallic systems

    International Nuclear Information System (INIS)

    Barinov, A.S.; Karlina, O.K.; Ojovan, M.I.

    1996-01-01

    Heat generating systems on the base of powder metallic fuel were used for the removal of contaminated asphalt layers. Decontamination of spots which had complex geometric form was performed. Asphalt layers with deep contamination were removed essentially all radionuclides being retained in asphalt residue. Only a small part (1 - 2 %) of radionuclides could pass to combustion slag. No radionuclides were detected in aerosol-gas phase during decontamination process

  5. Development of asphaltic mix with waste products use

    Directory of Open Access Journals (Sweden)

    Pugin Konstantin Georgievich

    2014-07-01

    Full Text Available The trend of high growth of the vehicle fleet in Russia along with the positive impact on the socio-economic development of the country has a number of adverse consequences, one of which is the high accident rate on the roads. The paper considers modern way to provide the safe vehicles flow with the use of colored asphalt, which is a kind of hot asphalt and can have a variety of colors, which consists of coloring pigments. The conventional method of coloring the asphalt mix is produced by adding color rubble or pigmenting additives. The task, which was put forward, was the establishment of such road concrete mix, from which, without the use of primary materials and without increasing the consumption of bitumen, asphalt concrete road surfaces of acceptable strength could be obtained. As a pigment the dust of gas purification system of electrical furnace DSP - 60 of «Kamastal» plant, Perm, was used. The composition of the dust waste from the furnace consists of metal oxides and silicates. Dust-gas-cleaning is a fine powder with a high specific surface (1.2…2.5 thousand cm /g and bulk density of 3.7…4.2 g/cm . The powder color is dark brown. The density of the ready colored asphalt samples is 2.47...2.49 g/cm , and water saturation is 3.50…3.55 %. As a result of the research the diagrams of the dependence of road concrete mix’s water saturation from dust percentage and a diagram of dependence of concrete mixes’ durability from dust percentage at t = 20° and 50° C were built. After analyzing the obtained curves it can be concluded that the increase of the percentage of dust leads to increase of water saturation of road concrete mix and reduced strength. Thus, the developed asphalt concrete mix allows visually separating the lanes on the road, it has the relevant regulatory requirements durability and water resistance. This mixture corresponds to the type B mark III and can be used in regions I, II, and partly III of road-climatic zones

  6. Impact of the Superpave hot mix asphalt properties on its permanent deformation behavior

    Directory of Open Access Journals (Sweden)

    Qasim Zahra

    2018-01-01

    Full Text Available In Iraq, the severity of rutting has increased in asphalt pavements possibly due to the increase in truck axle loads, tyre pressure, and high pavement temperature in summer. As of late, Superpave has been accounted as an enhanced system for performance based design, analysis of asphalt pavement performance prediction for asphalt concrete mixes. In this research the development of permanent deformation in asphalt concrete under repeated loadings was investigated, Wheel-Tracking apparatus has been used in a factorial testing program during which 44 slab samples were tested to simulate actual pavement. The objectives of the present research include; investigating the main factors affecting rutting in asphalt concrete mixture, quantifying the effect of SBS polymer and steel reinforcement on asphalt concrete mixtures in addition to studying the effect of variables on the asphalt concrete mixes against moisture sensitivity. It has been determined that that increasing of compaction temperature from 110 to 150°C will decrease the permanent deformation by 20.5 and 15.6 percent for coarse and fine gradation control asphalt mixtures, respectively. While the permanent deformation decreases by 21.3 percent when the compaction temperature is increased from 110 to 150°C for coarse gradation SBS modified asphalt mixtures.

  7. Investigation of the Physical and Molecular Properties of Asphalt Binders Processed with Used Motor Oils

    Directory of Open Access Journals (Sweden)

    Mohyeldin Ragab

    2015-01-01

    Full Text Available In this work we investigated the performance aspects of addition of used motor oils (UMO to neat and crumb rubber modified asphalts (CRMA and related that to the change of molecular size distribution of modified asphalt’s fractions; asphaltenes, saturates, naphthene aromatics, and polar aromatics. Based on the results of temperature sweep viscoelastic tests, addition of crumb rubber modifier (CRM alone or with UMO results in the formation of internal network within the modified asphalt. Based on the results of short and long term aged asphalts, the utilization of combination of UMO and CRM enhanced the aging behavior of asphalt. Bending beam rheometer was utilized to investigate the low temperature behavior of UMO modified asphalts. Based on those tests, the utilization of the UMO and CRM enhanced the low temperature properties of asphalts. Based on the results of the asphalt separation tests and the Gel Permeation Chromatography (GPC analysis, it was found that saturates and naphthene aromatics are the two asphalt fractions that have similar molecular size fractions as those of UMO. However, UMO only shifts the molecular sizes of saturates after interaction with asphalt. Results also show that polar aromatics pose higher molecular size structures than UMO.

  8. The Variation Test and Extraction Equipment to Optimum Asphalt by Using Gasoline Solvent

    Science.gov (United States)

    Soehardi, Fitridawati

    2017-12-01

    Based on the Binamarga Specification 2010 at third revision, the extraction test should be carried out using the specimen from the loose asphalt mixture extracted from the back of the finisher bitumen machine. The purpose of this research is to find out the result of pretest and posttest extraction asphalt content. The Extraction test using two equipment, they are Soklet and Centrifuge. The specimens was used AMP, Asphalt Finisher and Core, which involved gasoline solvent. Based on the asphalt level extraction test results, the appropriate equipment was used centrifuge with the level accuracy as requirement of Binamarga Specification 2010 at third revision and the level of ease used as equipment in the field study. The asphalt content obtained for AMP 5,51%, Asphalt Finisher5,46% and Core 5.34%. As for the socket asphalt content obtained is AMP 5.55%, Asphalt Finisher 5.50% and Core core 5. 41%. The extract test value of asphalt content decreased, so it can be formulated KA JMF value of Job mix used was 5.56% with the tolerance given according to Binamarga Specification 2010 at third revision is ± 0.30%. In accordance with the results obtained then the results of a centrifuge tool that matches and meets the requirements of time, accuracy of results and economic value.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

  10. Investigation on the temperature of the asphalt-concrete facing of embankment dams

    Directory of Open Access Journals (Sweden)

    Karel Adam

    2016-01-01

    Full Text Available Asphalt concrete is a traditional material used for the constructions of upstream sealing of reservoir dams, particularly in upper reservoirs of pumped storage hydroelectric plants. The asphalt layer is often exposed to significant fluctuations of temperature caused, for example, by heating the facing from the sun and by its subsequent rapid cooling by water during reservoir periodical filling. To better understand the physical phenomena and behaviour of the facing in terms of vapour diffusion, the state of stress, etc., it is necessary to know temperature phenomena in the asphalt facing. This paper describes the measurement of temperature in the asphalt facing of the Dlouhe Strane pumped storage hydroelectric plant and its evaluation using 1D numerical model of heat flow in the asphalt concrete facing. Numerical simulation for selected load scenarios enabled the temperature phenomena that take place in the construction of the asphalt-concrete facing to be quantified. The analysis shows that during insolation, the asphalt facing is exposed to the significant temperature rise on its surface and also over its whole thickness. Similarly during frost weather the facing becomes frozen in its entire thickness. During the day cycle the temperature in the asphalt layers changes significantly. However, the temperature in the underlying rockfill dam body becomes steady approximately at the depth of 1.0 m. Keywords: Asphalt concrete facing, Temperature distribution analysis, Embankment dam

  11. Laboratory Study on the Fatigue Resistance of Asphaltic Concrete Containing Titanium Dioxide

    Directory of Open Access Journals (Sweden)

    Buhari Rosnawati

    2018-01-01

    Full Text Available This study aims to evaluate the fatigue performance of modified asphalt mixture using Indirect Tensile Fatigue Test. Titanium Dioxide (TiO2 powder in a form of rutile was used for producing asphalt concrete with lower mixing and compaction temperature compared to conventional hot mix asphalt without reducing its physical and mechanical also resistance to fatigue. The characteristic of the asphalt and modified asphalt was evaluated using penetration test, softening test and rotational viscosity test. Titanium dioxide of 2%, 4%, 6%, 8% and 10% by weight of asphalt has been incorporated into unaged 80/100 asphalt mix in order to improvise its performance and to fulfill the objectives of this experimental study. As a result, TiO2 as an additive is potential to decrease the penetration and increasing the softening point of the asphalt. In terms of fatigue performance testing, addition TiO2 additive does help in improving the fatigue properties as it shows greater result than the control asphalt. In conclusion, TiO2 is great in improving fatigue properties.

  12. Laboratory Study on the Fatigue Resistance of Asphaltic Concrete Containing Titanium Dioxide

    Science.gov (United States)

    Buhari, Rosnawati; Ezree Abdullah, Mohd; Khairul Ahmad, Mohd; Azhar Tajudin, Saiful; Khatijah Abu Bakar, Siti

    2018-03-01

    This study aims to evaluate the fatigue performance of modified asphalt mixture using Indirect Tensile Fatigue Test. Titanium Dioxide (TiO2) powder in a form of rutile was used for producing asphalt concrete with lower mixing and compaction temperature compared to conventional hot mix asphalt without reducing its physical and mechanical also resistance to fatigue. The characteristic of the asphalt and modified asphalt was evaluated using penetration test, softening test and rotational viscosity test. Titanium dioxide of 2%, 4%, 6%, 8% and 10% by weight of asphalt has been incorporated into unaged 80/100 asphalt mix in order to improvise its performance and to fulfill the objectives of this experimental study. As a result, TiO2 as an additive is potential to decrease the penetration and increasing the softening point of the asphalt. In terms of fatigue performance testing, addition TiO2 additive does help in improving the fatigue properties as it shows greater result than the control asphalt. In conclusion, TiO2 is great in improving fatigue properties.

  13. The Effect of SBS Polymer on the Dynamic Properties of Asphalt

    Directory of Open Access Journals (Sweden)

    H. Ziari

    2008-12-01

    Full Text Available Polymer application for the improvement and modification of the bitumen used in roads surfaces has expanded in recent decades. The roads engineers and constructors, therefore, have used the modified bitumen in asphalts helping in this way to increase roads and pavements service life and improving the durability of the roads and asphalts. The bitumen used in asphalt mixture constitutes only a low percentage of the weight of this mixture (between 4% and 6%, but even this small amount has a significant effect on asphalt performance. The polymers that are mostly used in promoting the bitumen specifications are polymer modifiers including: styrenebutadiene- styrene (SBS, as well as similar polymers such as styrene-butadiene-rubber (SBR, ethylene-vinylacetate (EVA and polyethylene (PE. Polymers as the most important family of bitumen modifiers are added to bitumen to improve bitumen performance and to increase its effectiveness. Among the existing polymers, SBS is considered as the best bitumen modifier. In this research, SBS as one of the elastomer-thermoplast modifiers was added in different weights (2%-5% to bitumen 60/70 in Isfahan Refinery and its effect on asphalt properties were investigated. Adding this polymer to bitumen improves the Marshall stability of sample asphalt, flow, module of rupture and asphalt content voids. However, it has a minor effect on asphalt special weight. Adding SBS would also lead to asphalt fatigue life.

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

    Directory of Open Access Journals (Sweden)

    Andrzej Plewa

    2014-11-01

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

  15. Evaluation of rheological and thermic properties of neat and modified asphalt with a waste of LDPE

    Directory of Open Access Journals (Sweden)

    William Andrés Castro López

    2016-01-01

    Full Text Available Context: The asphalt technology and modified asphalt mixtures has been widely used and studied, worldwide. Adding polymers to asphalt modifies mechanical, chemical and rheological properties, trying to improve behavior of the mixtures subjected to different environmental and load conditions. The paper report results from rheological and thermal characterization on conventional 60-70 asphalt cement and 60-70 asphalt cement modified by introducing a waste of low density polyethylene (LDPE. Method: Modification of the asphalt was performed by wet way in a proportion of LDPE/CA=5% with respect to the mass. Rheological (using DSR, Thermogravimetry (TGA and Differential Scanning Calorimetry (DSC techniques were performed. Results and Conclusions: The modified asphalt develops a remarkable increase in stiffness and improvement of the performance grade at high temperatures of service. Additionally, the modified asphalt is more resistant to oxidation and aging processes due to heat. However, the asphalt modified showed a decrease in crack resistance at low and intermediate temperatures of service.

  16. Modification of Iraqi Asphalt 40/50 Properties Using Saw Dust (SD and Natural Rubber Latex

    Directory of Open Access Journals (Sweden)

    Rusul l M. Darwesh

    2018-04-01

    Full Text Available The aim of this research is to enhance the fundamental properties for asphalt binder as those spec-ifications relate to performance of asphalt mixtures. In this paper studied the effect of add (2, 4 % SD in different sizes and (3, 5 and 7% Natural rubber latex to the straight asphalt 40/50 produced from Al-Dura refinery at 160C, it was added each additive separately and then added together to asphalt in same temperature, then tested physically and mechanically according to the American Society for Testing and Materials (ASTM, the result showed largely improvement.

  17. Experimental investigation of asphalt mixture containing Linz-Donawitz steel slag

    Directory of Open Access Journals (Sweden)

    Jens Groenniger

    2017-08-01

    Full Text Available Standard asphalt mixtures for road infrastructures consist of natural aggregate and bitumen. A number of research efforts have successfully investigated the possibility of replacing the conventional aggregate skeleton with industrial by-products such as slag originating from steel production process. However, little is known on the effect of steel slag on the mixtures performance properties such as resistance to low-temperature cracking and to permanent deformation, stiffness and fatigue. This paper presents a comprehensive investigation on the fundamental performance properties of different types of asphalt mixtures prepared with 100% LD slag aggregate and a conventional asphalt mixture containing natural Gabbro aggregate. Sophisticated testing methods were used to evaluate the key performance parameters for the set of asphalt mixtures investigated. In this study, low temperature cracking was addressed through thermal stress restrained specimen tests. Penetration tests and cyclic compression tests were used to evaluate the response of asphalt binder and asphalt mixture to permanent deformation due repeated loading, respectively. The cyclic indirect tensile test was selected for investigating both stiffness properties and fatigue resistance. For this purpose the complex stiffness modulus was measured to quantify material stiffness under different temperature and loading conditions providing information on the visco-elasto-plastic material behavior. Fatigue tests were used to determine the progressive and localized material damage caused by cyclic loading. The experimental results indicate that asphalt mixtures prepared with LD slag are suitable for asphalt pavement construction and that in most cases they perform better than conventional asphalt mixtures prepared with Gabbro aggregate.

  18. The Effect of Aging on the Cracking Resistance of Recycled Asphalt

    Directory of Open Access Journals (Sweden)

    Mojtaba Mohammadafzali

    2017-01-01

    Full Text Available Fatigue cracking is an important concern when a high percentage of Reclaimed Asphalt Pavement (RAP is used in an asphalt mixture. The aging of the asphalt binder reduces its ductility and makes the pavement more susceptible to cracking. Rejuvenators are often added to high-RAP mixtures to enhance their performance. The aging of a rejuvenated binder is different from virgin asphalt. Therefore, the effect of aging on a recycled asphalt mixture can be different from its effect on a new one. This study evaluated the cracking resistance of 100% recycled asphalt binders and mixtures and investigated the effect of aging on this performance parameter. The cracking resistance of the binder samples was tested by a Bending Beam Rheometer. An accelerated pavement weathering system was used to age the asphalt mixtures and their cracking resistance was evaluated by the Texas Overlay Test. The results from binder and mixture tests mutually indicated that rejuvenated asphalt has a significantly better cracking resistance than virgin asphalt. Rejuvenated mixtures generally aged more rapidly, and the rate of aging was different for different rejuvenators.

  19. How do Category Managers Manage?

    DEFF Research Database (Denmark)

    Hald, Kim Sundtoft; Sigurbjornsson, Tomas

    2013-01-01

    The aim of this research is to explore the managerial role of category managers in purchasing. A network management perspective is adopted. A case based research methodology is applied, and three category managers managing a diverse set of component and service categories in a global production...... firm is observed while providing accounts of their progress and results in meetings. We conclude that the network management classification scheme originally deve loped by Harland and Knight (2001) and Knight and Harland (2005) is a valuable and fertile theoretical framework for the analysis...

  20. 10CFR61 waste form conformance program for asphalted radwaste

    International Nuclear Information System (INIS)

    Kobran, M.J.; Guarini, W.J.

    1987-01-01

    With the enactment of Title 10, Code of Federal Regulation, Part 61, ''Licensing Requirements for Land Disposal of Radioactive Waste'' came the imposition of new requirements on licensees who dispose of radioactive waste via shallow land burial. Specifically, 10CFR61 both imposed a waste classification system requiring segregation of waste according to hazard and established waste performance characteristics required to enhance stability of the burial site. In order to provide licensees with guidance regarding implementation of applicable requirements of 10CFR61, the NRC low level Waste Licensing Branch issued two Technical Positions. To demonstrate compliance of asphalted radwaste produced with oxidized asphalt with 10CFR61 criteria and the NRC's Technical Position, five utilities combined resources. The five utilities sponsoring the program were Public Service Electric and Gas Company, Niagara Mohawk Power Company, Detroit Edison Company, New Hampshire Yankee, and Consumers Power Comany

  1. Decontamination by shotblasting of radioactivity deposited on an asphalt road

    International Nuclear Information System (INIS)

    Warming, L.

    1987-01-01

    Long-lived fission products may be deposited in the environment after a serious reactor accident. From previous experiments it is known that if firehosing is to be used for decontamination it has to be done soon after the deposition. It is therefore worthwhile to study another decontamination method. An experimental study has been conducted of how well shotblasting can remove contamination from an asphalt road. In shotblasting a thin layer of the surface is loosened by the impact of small steel balls, and in the same procedure the surface dust is vacuumed up and the steel balls recovered. The contaminant was 86 Rb, which behaves as caesium. As reference, the weathering of identical contamination on an asphalt road, a concrete road and a road covered with small concrete stones was studied concurrently. (author)

  2. Homological algebra in -abelian categories

    Indian Academy of Sciences (India)

    Deren Luo

    2017-08-16

    Aug 16, 2017 ... Homological algebra in n-abelian categories. 627. We recall the Comparison lemma, together with its dual, plays a central role in the sequel. Lemma 2.1 [13, Comparison lemma 2.1]. Let C be an additive category and X ∈ Ch. ≥0(C) a complex such that for all k ≥ 0the morphism dk+1. X is a weak cokernel ...

  3. Aggregate Toughness/Abrasion Resistance and Durability/Soundness Tests Related to Asphalt Concrete Performance in Pavements

    Science.gov (United States)

    1998-03-01

    The properties of aggregates used in asphalt concretes are very important to the performance of the pavements in which the asphalt concretes are used. Often pavement distress, such as stripping and rutting, can be traced directly to the aggregates us...

  4. Quantify the energy and environmental effects of using recycled asphalt and recycled concrete for pavement construction phase I : final report.

    Science.gov (United States)

    2009-08-01

    The objective of this study is to quantify the energy and environment impacts from using recycled materials : for highway construction. Specifically, when recycled asphalt pavement is re-used for producing hot mix : asphalt or when recycled concrete ...

  5. Effects of laboratory heating, cyclic pore pressure, and cyclic loading on fracture properties of asphalt mixture [summary].

    Science.gov (United States)

    2012-04-01

    Asphalt pavement ages continuously, beginning with production and construction and thoughout its service life. "Aging" refers to many changes in asphalt properties over time that generally result in increased pavement damage. Because aging is often a...

  6. Quality of bitumens in asphalt hot-mixes with emphasis on the durability of constructed premix surfacings.

    CSIR Research Space (South Africa)

    Van Assen, EJ

    1992-08-01

    Full Text Available time. Asphalt technologists' ultimate quest is for performance-related specifications that will ensure the procurement of quality bitumens which could produce asphalts with desirable performance during construction, and which will resist physical...

  7. Rutting resistance of asphalt mixture with cup lumps modified binder

    Science.gov (United States)

    Shaffie, E.; Hanif, W. M. M. Wan; Arshad, A. K.; Hashim, W.

    2017-11-01

    Rutting is the most common pavement distress in pavement structures which occurs mainly due to several factors such as increasing of traffic volume, climatic conditions and also due to construction design errors. This failure reduced the service life of the pavement, reduced driver safety and increase cost of maintenance. Polymer Modified Binder has been observed for a long time in improving asphalt pavement performance. Research shows that the use of polymer in bituminous mix not only improve the resistance to rutting but also increase the life span of the pavement. This research evaluates the physical properties and rutting performance of dense graded Superpave-designed HMA mix. Two different types of dense graded Superpave HMA mix were developed consists of unmodified binder mix (UMB) and cup lumps rubber (liquid form) modified binder mix (CLMB). Natural rubber polymer modified binder was prepared from addition of 8 percent of cup lumps into binder. Results showed that all the mixes passed the Superpave volumetric properties criteria which indicate that these mixtures were good with respect to durability and flexibility. Furthermore, rutting results from APA rutting test was determined to evaluate the performance of these mixtures. The rutting result of CLMB demonstrates better resistance to rutting than those prepared using UMB mix. Addition of cup lumps rubber in asphalt mixture was found to be significant, where the cup lumps rubber has certainly improves the binder properties and enhanced its rutting resistance due to greater elasticity offered by the cup lumps rubber particles. It shows that the use of cup lumps rubber can significantly reduce the rut depth of asphalt mixture by 41% compared to the minimum rut depth obtained for the UMB mix. Therefore, it can be concluded that the cup lumps rubber is suitable to be used as a modifier to modified binder in order to enhance the properties of the binder and thus improves the performance of asphalt mixes.

  8. Moisture damage susceptibility of asphalt mixtures: Experimental characterization and modelling

    OpenAIRE

    Varveri, A.

    2017-01-01

    A well-functioning, long-lasting and safe highway infrastructure network ensures the mobility of people and facilitates the transport of goods, promoting thus environmental, economic, and social sustainability. The development of sustainable highway infrastructure requires, among other activities, the construction of pavement systems with enhanced durability. Moisture damage in asphalt pavements is associated with inferior performance, unexpected failures and reduced service life. All of thes...

  9. Evaluation of nuclear asphalt-content gauges. Final report

    International Nuclear Information System (INIS)

    1989-03-01

    The study evaluated the accuracy and precision of the Troxler, Model 3241-C, and CPN, Model AC-2, Nuclear Asphalt Content Gauges. To achieve precisions at plus or minus 0.15% 95% of the time, it was necessary to establish special procedures for making test samples, controlling environment, and calibration. Both gauges provided acceptable results utilizing a 3-point calibration. Their use in the field would be acceptable when the proper procedures are followed

  10. Data categories for marine planning

    Science.gov (United States)

    Lightsom, Frances L.; Cicchetti, Giancarlo; Wahle, Charles M.

    2015-01-01

    The U.S. National Ocean Policy calls for a science- and ecosystem-based approach to comprehensive planning and management of human activities and their impacts on America’s oceans. The Ocean Community in Data.gov is an outcome of 2010–2011 work by an interagency working group charged with designing a national information management system to support ocean planning. Within the working group, a smaller team developed a list of the data categories specifically relevant to marine planning. This set of categories is an important consensus statement of the breadth of information types required for ocean planning from a national, multidisciplinary perspective. Although the categories were described in a working document in 2011, they have not yet been fully implemented explicitly in online services or geospatial metadata, in part because authoritative definitions were not created formally. This document describes the purpose of the data categories, provides definitions, and identifies relations among the categories and between the categories and external standards. It is intended to be used by ocean data providers, managers, and users in order to provide a transparent and consistent framework for organizing and describing complex information about marine ecosystems and their connections to humans.

  11. Prediction of Asphalt Creep Compliance Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Zofka A.

    2012-06-01

    Full Text Available Creep compliance of the hot-mix asphalt (HMA is a primary input of the pavement thermal cracking prediction model in the recently developed Mechanistic-Empirical Pavement Design Guide (M-EPDG in the US. The HMA creep compliance is typically determined from the Indirect Tension (IDT tests and requires complex experimental setup. On the other hand, creep compliance of asphalt binders is determined from a relatively simple three- point bending test performed in the Bending Beam Rheometer (BBR device. This paper discusses a process of training an Artificial Neural Network (ANN to correlate the creep compliance values obtained from the IDT with those from an innovative approach of testing HMA beams in the BBR. In addition, ANNs are also trained to predict HMA creep compliance from the creep compliance of asphalt binder and vice versa using the BBR setup. All trained ANNs exhibited a very high correlation of 97 to 99 percent between predicted and measured values. The binder creep compliance curves built on the ANN-predicted values also exhibited good correlation with those obtained from laboratory experiments. However, the simulation of trained ANNs on the independent dataset produced a significant deviation from the expected values which was most likely caused by the differences in material composition, such as aggregate type and gradation, presence of recycled additives, and binder type.

  12. Microstructural and rheological analysis of fillers and asphalt mastics

    International Nuclear Information System (INIS)

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

    2017-01-01

    Pavements are made of different grades of mineral aggregates and organic binder. The aggregates are sorted in different sizes and different amount which are mixed together with bitumen. The finest mineral fraction (d<0.063 mm) is called filler. This component has an important role in asphalt mixture - it fills the gaps between the aggregates and if mixed with bitumen (which is called asphalt mastics) it sticks the larger particles together. Particle size, microstructure and surface properties of fillers highly affect the cohesion with bitumen, therefore the aim of our research was to investigate the microstructure of mineral fillers (limestone, dolomite) which are used in Hungarian road constructions with the use of different techniques (particle size distribution, scanning electronmicroscopy tests, mercury intrusion porosimetry, BET specific surface tests, determination of hydrophobicity). After the tests of fillers, asphalt mastics were prepared and rheological examinations were obtained. These examinations served to observe the interaction and the effect of fillers. The stiffening effect of fillers and the causes of rutting were also investigated. Based on our results, it can be stated that particle size, hydrophobic properties and the amount of fillers highly affect the rheological properties of mastics. (paper)

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

    Directory of Open Access Journals (Sweden)

    Nihat MOROVA

    2015-09-01

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

  14. Representative volume element of asphalt pavement for electromagnetic measurements

    Directory of Open Access Journals (Sweden)

    Terhi Pellinen

    2015-02-01

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

  15. 76 FR 56883 - Designation of Product Categories for Federal Procurement

    Science.gov (United States)

    2011-09-14

    ... deodorizers; asphalt and tar removers; asphalt restorers; blast media; candles and wax melts; electronic...: Specialty inks used to add extra characteristics or features to printed material; inks used for coated paper... aspect of this issue. 6. Today's proposed rule is expected to have both positive and negative impacts on...

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

    DEFF Research Database (Denmark)

    Feng, Huan; Pettinari, Matteo; Stang, Henrik

    2015-01-01

    In this paper, the viscoelastic behavior of asphalt mixture was studied by using discrete element method. The dynamic properties of asphalt mixture were captured by implementing Burger’s contact model. Different ways of taking into account of the normal and shear material properties of asphalt mi...

  17. A Comparative Life Cycle Assessment of Hot Mixes Asphalt Containing Bituminous Binder Modified with Waste and Virgin Polymers

    NARCIS (Netherlands)

    Oliveira dos Santos, Joao Miguel; Cerezo, Veronique; Soudani, Khedoudja; Bressi, Sara

    2018-01-01

    This paper presents the results of a life cycle assessment undertaken to compare the potential environmental impacts associated with the use of asphalt surface mixtures produced with polymer modified bitumen with those of a conventional asphalt surface mixture. Seven types of hot mix asphalt

  18. Determination of the most favorable experimental conditions for obtaining asphalt emulsions modified with discarded polymers in the reconstruction of pavements

    International Nuclear Information System (INIS)

    Coward Ugalde, Hector Arturo

    2014-01-01

    The most favorable experimental conditions are determined for the production of asphalt emulsions modified with tire scrap rubber, petroleum material and recycled asphalt in the reconstruction of flexible pavements in a slow breaking process. Asphalt emulsions are made with 65% V/V of fluidized asphalt at different conditions of operation and composition of soap solution. The equipment of a centrifugal pump and a colloidal mill are used. Two different compositions are employed to make soap solutions. The best conditions to prepare the asphalt emulsions in the pilot plant have been: a stirring speed of 2100 rpm in the centrifugal pump and a speed of 3300 rpm of the colloidal mill. Asphaltic grouts made with asphalt emulsion modified to 1% m/m of rubber have shown the best coverage in the stripping test, evidencing little asphalt release, high adhesion of the asphalt on the aggregate and good stability. Asphalt emulsions with rubber are recommended with a granulometry that passes the No. 200 mesh for rubber and use the indicated equipment to carry out the process of asphalt modification to obtain better results in the performance of asphalt emulsion [es

  19. 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…

  20. Influence of limestone fillers on combustion characteristics of asphalt mortar for pavements

    DEFF Research Database (Denmark)

    Ke, Wu; Kai, Zhu; Wu, Hao

    2014-01-01

    Asphalt materials will be ignited and release significant toxic fumes within tunnel fires. Thus, combustion characteristics of asphalt materials used in road tunnel should be studied in order to limit such an adverse effect. In the present work we study the influence of limestone fillers on combu...

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

    Directory of Open Access Journals (Sweden)

    Ramez A Al-Mansob

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

  2. Influence of superplasticizer on the rheology of fresh cement asphalt paste

    Directory of Open Access Journals (Sweden)

    Jianwei Peng

    2015-12-01

    Full Text Available Cement asphalt (CA paste is an organic–inorganic composite material of cement and asphalt emulsion. Its complicated rheological behavior affects its site application in high speed railway. Superplasticizers (SPs are usually used to improve the construction properties of fresh CA mortar. However, the principle of SPs acting on the rheology of CA paste is seldom studied. In this paper, the effects of polycarboxylate (PCA and naphthalenesulfonate (PNS on the rheological properties of CA pastes, asphalt emulsions (both anionic and cationic and cement pastes were studied, respectively from the viewpoint of adsorption and zeta potential. Centrifugation method was used to determine the adsorption of asphalt onto cement particle, electroacoustic method was employed to study the zeta potential of cement particles of concentrated paste, and optical microscopy was used to observe the dispersion of particles. The results suggest that both PCA and PNS can decrease the yield stress and apparent viscosity of CA pastes. The effect of SPs on the rheology of CA paste can be explained by two reasons. First, PNS can adsorb on both asphalt and cement surface, change the zeta potential and then decrease their yield stress and viscosity, while PCA only adsorb on cement surface. Second, the competitive adsorption of SPs and asphalt prevents asphalt from adsorbing on cement surface and then more asphalt droplets are released into aqueous solution, thereby enhancing the particle dispersion.

  3. Laboratory investigation of the performances of cement and fly ash modified asphalt concrete mixtures

    Directory of Open Access Journals (Sweden)

    Suched Likitlersuang

    2016-09-01

    Full Text Available The influence of filler materials on volumetric and mechanical performances of asphalt concrete was investigated in this study. The AC60/70 asphalt binder incorporating with cement and fly ash as filler materials was mixed with limestone following the Marshall mix design method. The filler contents of cement and/or fly ash were varied. The non-filler asphalt concrete mixtures of the AC60/70 and the polymer modified asphalt were prepared for the purpose of comparison. The investigation programme includes the indirect tensile test, the resilient modulus test and the dynamic creep test. The tests are conducted under the humid temperate environments. All tests were then carried out under standard temperature (25 °C and high temperature (55 °C by using a controlled temperature chamber via the universal testing machine. The wet-conditioned samples were prepared to investigate the moisture susceptibility. Results show that cement and/or fly ash were beneficial in terms of improved strength, stiffness and stripping resistance of asphalt mixture. In addition, the combined use of cement and fly ash can enhance rutting resistance at wet and high temperature conditions. The results indicate that the strength, stiffness and moisture susceptibility performances of the asphalt concrete mixtures improved by filler are comparable to the performance of the polymer modified asphalt mixture. Keywords: Asphalt concrete, Filler, Resilient modulus, Dynamic creep test, Moisture susceptibility

  4. Volumetric Analysis and Performance of Hot Mix Asphalt with Variable Rap Content

    Directory of Open Access Journals (Sweden)

    Arshad Ahmad Kamil

    2017-01-01

    Full Text Available Incorporating Reclaimed Asphalt Pavement (RAP to the asphalt concrete mixture for highway construction offer many benefits including energy consumption, conservation of natural resources and preservation of the environment to associated emissions. This paper presents a study on performance of Hot Mix Asphalt with variable RAP content. The study is carried out to evaluate the Marshall Properties and Performance of RAP-Asphalt mixes using conventional asphaltic concrete mix AC14. Marshall Mix Design Method was used to produce control mix (0% RAP and RAP-Asphalt mixes samples which consist of 15% RAP, 25% RAP and 35% RAP in accordance with Specifications for Road Works of Public Works Department, Malaysia. The Marshall Properties analysis was performed to ensure compliance with Marshall Requirements, The resilient modulus test was performed to measure the stiffness of the mixes while Modified Lottman test was conducted to evaluate the moisture susceptibility of these mixes. The results obtained showed that there were no substantial difference in Marshall Properties, moisture susceptibility and indirect tensile strength between RAP-Asphalt mixes with the control mix. The test results indicated that recycled mixes performed as good as the performance of conventional HMA in terms of moisture susceptibility and resilient modulus. It is recommended that further research be carried out for asphalt mixes containing more than 35% of RAP material.

  5. On the combined effect of moisture diffusion and cyclic pore pressure generation in asphalt concrete

    NARCIS (Netherlands)

    Varveri, A.; Scarpas, A.; Collop, A.; Erkens, S.M.J.G.

    2014-01-01

    In this paper, a new moisture conditioning protocol which attempts to distinguish the contributions of long- and short-term moisture damage, i.e. moisture diffusion and cyclic pore pressure generation, in asphalt mixtures is presented. The capability of the proposed protocol to rank various asphalt

  6. Preparation and Properties of Asphalt Binders Modified by THFS Extracted From Direct Coal Liquefaction Residue

    Directory of Open Access Journals (Sweden)

    Jie Ji

    2017-11-01

    Full Text Available This paper aims to study the preparation and viscoelastic properties of asphalt binder modified by tetrahydrofuran soluble fraction (THFS extracted from direct coal liquefaction residue. The modified asphalt binders, which blended with SK-90 (control asphalt binder and 4%, 6%, 8% and 10% THFS (by weight of SK-90, were fabricated. The preparation process for asphalt binder was optimized in terms of the orthogonal array test strategy and gray correlation analysis results. The properties of asphalt binder were measured by applying Penetration performance grade and Superpave performance grade specifications. In addition, the temperature step and frequency sweep test in Dynamic Shear Rheometer were conducted to predict the rheological behavior, temperature and frequency susceptibility of asphalt binder. The test results suggested the optimal preparation process, such as 150 °C shearing temperature, 45 min shearing time and 4000 rpm shearing rate. Subsequently, the addition of THFS was beneficial in increasing the high-temperature properties but decreased the low-temperature properties and resistance to fatigue. The content analysis of THFS showed the percentage of 4~6% achieved a balance in the high-and-low temperature properties of asphalt binder. The asphalt binder with higher THFS content exhibited higher resistance to rutting and less sensitivity to frequency and temperature.

  7. Performance characterizations of asphalt binders and mixtures incorporating silane additive ZycoTherm

    Science.gov (United States)

    Hasan, Mohd Rosli Mohd; Hamzah, Meor Othman; Yee, Teh Sek

    2017-10-01

    Experimental works were conducted to evaluate the properties of asphalt binders and mixtures produced using a relatively new silane additive, named ZycoTherm. In this study, 0.1wt% ZycoTherm was blended with asphalt binder to enable production of asphalt mixture at lower than normal temperatures, as well as improve mix workability and compactability. Asphalt mixture performances towards pavement distresses in tropical climate region were also investigated. The properties of control asphalt binders (60/70 and 80/10 penetration grade) and asphalt binders incorporating 0.1% ZycoTherm were reported based on the penetration, softening point, rotational viscosity, complex modulus and phase angle. Subsequently, to compare the performance of asphalt mixture incorporating ZycoTherm with the control asphalt mixture, cylindrical samples were prepared at recommended temperatures and air voids depending on the binder types and test requirements. The samples were tested for indirect tensile strength (ITS), resilient modulus, dynamic creep, Hamburg wheel tracking and moisture induced damage. From compaction data using the Servopak gyratory compactor, specimen prepared using ZycoTherm exhibit higher workability and compactability compared to the conventional mixture. From the mixture performance test results, mixtures prepared with ZycoTherm showed comparable if not better performance than the control sample in terms of the resistance to moisture damage, permanent deformation and cracking.

  8. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations 2 Table 2 of Subpart AAAAAAA of Part 63 Protection of Environment... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * * 1...

  9. Grade determination of crumb rubber-modified performance graded asphalt binder.

    Science.gov (United States)

    2013-08-01

    Due to particulates common in crumb rubber-modified asphalt binders, conventional PG grading using the Dynamic : Shear Rheometer (DSR) with a gap height of 1.0 mm may not be valid and in accordance with current specifications. : Asphalt binder testin...

  10. Use of rubber asphalt binder with graded aggregate for seal coats

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    It has been known that incorporating rubber particles into asphalt can improve highway pavement performance. This paper describes a test program on pavement construction using asphalts containing recycled rubber. During the summer 1978, eight test sections were constructed in parts of the Saskatchewan road system to evaluate seal coats using rubber-asphalt as a binder membrane and a graded aggregate as protective cover. Test sections were chosen to represent typical road surface types and different states of repair for each type. These types included prime subgrade, cold-mix on subgrade, primed granular base course, asphaltic concrete on granular base, and full depth asphaltic concrete. Problems with construction materials, techniques, and equipment are discussed. Performance and economics were evaluated to determine whether low cost cold mix and current seal coat surfaces could be replaced successfully and economically by this method of construction. It was shown that use of reclaimed rubber for rubberized asphalt seal coats on Saskatechewan highways is a practical construction application. The economic justification for rubber asphalt seals will be determined after a full assessment of performance. Initial indications are that Saskatchewan graded aggregates are a suitable cover material for the rubberized asphalt membranes used in the trials. 8 refs., 16 figs., 7 tabs.

  11. Review of warm mix rubberized asphalt concrete : Towards a sustainable paving technology

    NARCIS (Netherlands)

    Wang, H.; Liu, X.; Apostolidis, P.; Scarpas, Athanasios

    2018-01-01

    In recent years, transportation agencies and the general public alike are demanding increased considerations of sustainability in transport infrastructure. Warm mix asphalt (WMA) is developed for reducing energy consumptions and emissions in asphalt paving industry. In addition, the use of

  12. Evaluation of recycled hot mix asphalt concrete on Route 220 : final report.

    Science.gov (United States)

    1985-01-01

    This report describes the performance of an approximately 8-mi section of roadway on which the rod two layers of asphalt concrete were milled, recycled through a conventional asphalt batch plant, and relaid. The recycled mix consisted of about 40% re...

  13. Investigation of the Asphalt Pavement Analyzer (APA) testing program in Nebraska.

    Science.gov (United States)

    2008-03-01

    The asphalt pavement analyzer (APA) has been widely used to evaluate hot-mix asphalt (HMA) rutting potential in mix : design and quality control-quality assurance (QC-QA) applications, because the APA testing and its data analyses are : relatively si...

  14. The use of atomic force microscopy to evaluate warm mix asphalt.

    Science.gov (United States)

    2013-01-01

    The main objective of this study was to use the Atomic Force Microscopy (AFM) to examine the moisture susceptibility : and healing characteristics of Warm Mix Asphalt (WMA) and compare it with those of conventional Hot Mix Asphalt (HMA). To : this en...

  15. Use of warm mix asphalt pavement on Route 9, in Durham.

    Science.gov (United States)

    2012-06-01

    A number of new technologies have been developed to lower the production and placement temperatures : of hot-mix asphalt (HMA). Generically, these technologies are referred to as warm-mix asphalt (WMA). : In Europe and to a lesser extent in North Ame...

  16. Use of warm mix asphalt pavement on Interstate 95, Carmel to Hampden, northbound.

    Science.gov (United States)

    2012-06-01

    A number of new technologies have been developed to lower the production and placement temperatures : of hot-mix asphalt (HMA). Generically, these technologies are referred to as warm-mix asphalt (WMA). : In Europe and to a lesser extent in North Ame...

  17. Modelling absorption in porous asphalt concrete for oblique incident sound waves

    NARCIS (Netherlands)

    Bezemer-Krijnen, Marieke; Wijnant, Ysbrand H.; de Boer, Andries; Sas, P; Moens, D.; Denayer, H.

    2014-01-01

    A numerical model to predict the sound absorption of porous asphalt has been developed. The approach is a combination between a microstructural approach and a finite element approach. The model used to describe the viscothermal properties of the air inside the pores of the asphalt is the low reduced

  18. Use of waste crushed glass for the production of hot-mix asphalt

    CSIR Research Space (South Africa)

    Anochie-Boateng, Joseph

    2016-08-01

    Full Text Available presents the development and evaluation of a new asphalt concrete mix that utilizes a sustainable crushed glass as a replacement material of a natural aggregate. The ultimate goal is to produce a cost-effective asphalt wearing course with comparative...

  19. Investigation of using steel slag in hot mix asphalt for the surface course of flexible pavements

    Science.gov (United States)

    Nguyen, Hien Q.; Lu, Dai X.; Le, Son D.

    2018-04-01

    The rapid development of heavy industry in Vietnam leads to the establishments of steel industry. Steel slag, a by-product of steelwork industry, under Vietnamese’s law, was considered as a deleterious solid waste which needed to be processed and landfilled. However, this has changed recently, and steel slag is now seen as a normal or non-deleterious solid waste, and has been studied for reuse in the construction industry. In this study, steel slag was used, as a replacement for mineral aggregate, in hot mix asphalt. Two hot mix asphalt mixtures with an equivalent nominal aggregate size of 12.5 (C12.5) and 19 mm (C19) were produced using steel slag. In addition, one conventional hot mix asphalt mixture of C19 was produced using mineral aggregate for comparison purpose. Investigation in laboratory condition and trial sections was carried out on Marshall tests, surface roughness, skid resistance, and modulus of the pavement before and after applying a new surface course of hot mix asphalt. The study showed that all steel slag asphalt mixtures passed the Marshall stability and flow test requirements. The skid resistance of steel slag hot mix asphalt mixtures for the surface course satisfied the Vietnamese specification for asphalt. Moreover, the pavement sections with the surface course of steel slag hot mix asphalt showed a considerable higher modulus than that of the conventional one. Only the roughness of the surface course paved with C19 did not pass the requirement of the specification.

  20. Investigation of self healing behaviour of asphalt mixes using beam on elastic foundation setup

    NARCIS (Netherlands)

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

    2012-01-01

    Self healing of asphalt mixes is known for more than four decades. However, it is a complex phenomenon which depends on the duration of the rest period, temperature, crack size, etc. In order to quantify the self healing behaviour of asphalt mixes, a test setup was proposed in this research using an

  1. Monitoring hot mix asphalt temperature to improve homogeneity and pavement quality

    NARCIS (Netherlands)

    ter Huerne, Henderikus L.; Miller, Seirgei Rosario; Doree, Andries G.; Santagata, E.

    2009-01-01

    This paper describes how controlled compaction practices lead to better quality asphalt. Therefore, it is important that during compaction operations the mixture is at a suitable temperature in order to achieve the specified degree of compaction. The University of Twente’s Asphalt Paving Research

  2. Thermodynamics between RAP/RAS and virgin aggregates during asphalt concrete production : a literature review.

    Science.gov (United States)

    2015-09-01

    In hot-mix asphalt (HMA) plants, virgin aggregates are heated and dried separately before being mixed with : RAP/RAS and virgin asphalt binder. RAP/RAS materials are not heated or dried directly by a burner to avoid : burning of aged binder coating o...

  3. Category O for quantum groups

    DEFF Research Database (Denmark)

    Andersen, Henning Haahr; Mazorchuk, Volodymyr

    2015-01-01

    We study the BGG-categories O_q associated to quantum groups. We prove that many properties of the ordinary BGG-category O for a semisimple complex Lie algebra carry over to the quantum case. Of particular interest is the case when q is a complex root of unity. Here we prove a tensor decomposition...... for simple modules, projective modules, and indecomposable tilting modules. Using the known Kazhdan–Lusztig conjectures for O and for finite-dimensional U_q-modules we are able to determine all irreducible characters as well as the characters of all indecomposable tilting modules in O_q . As a consequence......, we also recover the known result that the generic quantum case behaves like the classical category O....

  4. In situ construction of carbon nano-interconnects between the LiFePO{sub 4} grains using ultra low-cost asphalt

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wenkui; Zhou Xiaozheng [College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014 (China); Tao Xinyong, E-mail: tao@zjut.edu.c [College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014 (China); Huang Hui; Gan Yongping [College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014 (China); Wang Chuntao [College of Electromechanical Engineering, Zhejiang Ocean University, Hangzhou 316000 (China)

    2010-03-01

    LiFePO{sub 4}/C composite cathode materials with carbon nano-interconnect structures were synthesized by one-step solid state reaction using low-cost asphalt as both carbon source and reducing agent. Based on the thermogravimetry, differential scanning calorimetry, transmission electron microscopy and high-resolution transmission electron microscopy, a growth model was proposed to illustrate the formation of the carbon nano-interconnect between the LiFePO{sub 4} grains. The LiFePO{sub 4}/C composite shows enhanced discharge capacity (150 mAh g{sup -1}) with excellent capacity retention compared with the bare LiFePO{sub 4} (41 mAh g{sup -1}) due to the electronically conductive nanoscale networking provided by the asphalt-based carbon. The results prove that the asphalt is a perfect carbon source and reduction agent for cost-effective production of high performance LiFePO{sub 4}/C composite.

  5. Hippocampal activation during episodic and semantic memory retrieval: comparing category production and category cued recall.

    Science.gov (United States)

    Ryan, Lee; Cox, Christine; Hayes, Scott M; Nadel, Lynn

    2008-01-01

    Whether or not the hippocampus participates in semantic memory retrieval has been the focus of much debate in the literature. However, few neuroimaging studies have directly compared hippocampal activation during semantic and episodic retrieval tasks that are well matched in all respects other than the source of the retrieved information. In Experiment 1, we compared hippocampal fMRI activation during a classic semantic memory task, category production, and an episodic version of the same task, category cued recall. Left hippocampal activation was observed in both episodic and semantic conditions, although other regions of the brain clearly distinguished the two tasks. Interestingly, participants reported using retrieval strategies during the semantic retrieval task that relied on autobiographical and spatial information; for example, visualizing themselves in their kitchen while producing items for the category kitchen utensils. In Experiment 2, we considered whether the use of these spatial and autobiographical retrieval strategies could have accounted for the hippocampal activation observed in Experiment 1. Categories were presented that elicited one of three retrieval strategy types, autobiographical and spatial, autobiographical and nonspatial, and neither autobiographical nor spatial. Once again, similar hippocampal activation was observed for all three category types, regardless of the inclusion of spatial or autobiographical content. We conclude that the distinction between semantic and episodic memory is more complex than classic memory models suggest.

  6. FINANCIAL CONTROL AS A CATEGORY

    Directory of Open Access Journals (Sweden)

    Andrey Yu. Volkov

    2014-01-01

    Full Text Available The article reveals the basics of “financial control” as a category. The main attention is concentrated on the “control” itself (asa term, multiplicity of interpretation of“financial control” term and its juristic-practical matching. The duality of financial control category is detected. The identity of terms “financial control” and “state financial control” is justified. The article also offers ways of development of financial control juristical regulation.

  7. Synthesis and Characterization of New ‎Copolymers as Asphalt Additives

    Directory of Open Access Journals (Sweden)

    Firyal M. ‎ A

    2017-12-01

    Full Text Available Rheological properties of asphalt S50  were improved by adding different prepared copolymers as additives with high homogeneity of asphalts  samples.  Three types of copolymers were prepared  Poly  (Indene –Co- maleic anhydride(A1 Poly (Acrylonitrile –Co- Maleic anhydride (A2 and Poly (Dipentine –Co-Maleic anhydride (A3, the cross linking of (A3 to (A3d. by using sulfur.              These copolymers  were designed by inserting Maleic anhydride as  rings  containing through backbone of polymer chains to be high potentially to react with water to protect the crack of pavement .And moisture with inhibit bonding of crack of pavement, Many factors should be considered when prepared the additives to enhanced performance to be convenience cost, beneficial thermal safety ,   extended life of the asphalt, preparing conditions which gave high thermal resistance with more stabilities, all these prepared copolymer have been characterized by FTIR and H-NMR spectroscopies .Intrinsic viscosities were calculated. softening point and penetration were observed for all asphalts blends which were  compared with the  asphalt samples, which gave high thermal resistance with more stabilities.                                          The results  showed high properties of these blends when  compared with the original asphalt. The physical properties of a specific polymers are determined by the sequence and chemical structure , When polymers are added to asphalt , the properties of the modified asphalt cement depend on polymer characteristic of asphalt and compatibility of polymer with asphalt. All these prepared copolymers were tested by softening points and penetration for all  asphalt blends which were compared with the asphalt sample. All the Improvements made by adding polymers to asphalt included the Increasing the viscosity of the binder service, the thermal susceptibility of the binder

  8. Stress Regression Analysis of Asphalt Concrete Deck Pavement Based on Orthogonal Experimental Design and Interlayer Contact

    Science.gov (United States)

    Wang, Xuntao; Feng, Jianhu; Wang, Hu; Hong, Shidi; Zheng, Supei

    2018-03-01

    A three-dimensional finite element box girder bridge and its asphalt concrete deck pavement were established by ANSYS software, and the interlayer bonding condition of asphalt concrete deck pavement was assumed to be contact bonding condition. Orthogonal experimental design is used to arrange the testing plans of material parameters, and an evaluation of the effect of different material parameters in the mechanical response of asphalt concrete surface layer was conducted by multiple linear regression model and using the results from the finite element analysis. Results indicated that stress regression equations can well predict the stress of the asphalt concrete surface layer, and elastic modulus of waterproof layer has a significant influence on stress values of asphalt concrete surface layer.

  9. Sustainable Performance of Iraqi Asphalt Base Course Using Recycled Glass as Aggregate Replacement

    Directory of Open Access Journals (Sweden)

    Hamid Athab Eedan Al-Jameel

    2018-03-01

    Full Text Available Nowadays, a lot of waste glass produced through different sides of life. Applying sustainability has been widely used in different construction materials and flexible pavement was contained different recycled materials through different studies. Recycled glass, where it is nonmetallic and inorganic, it can neither be incinerated nor decomposed, so it may be difficult to reclaim, has been used as filler, fine and coarse aggregates in the asphalt base course. In this study, various standard asphalt tests, such as stability, flow, density and air voids, have been conducted on reference mix asphalt and mix asphalt with different percentages of recycled glass when it has been used as filler, fine and coarse aggregates in the base course. Generally, the results show good indication, especially when using 10% of the recycled glass instead of coarse aggregate with 40-50 asphalt grades. This percentage improves most characteristics such as strength retained index which indicates better performance than reference mix.  

  10. Road safety effects of porous asphalt: a systematic review of evaluation studies

    DEFF Research Database (Denmark)

    Elvik, R.; Greibe, Poul

    2005-01-01

    of eighteen estimates of the effect of porous asphalt on accident rates. No clear effect on road safety of porous asphalt was found. All summary estimates of effect indicated very small changes in accident rates and very few were statistically significant at conventional levels. Studies that have evaluated...... of these changes in risk factors on accident occurrence cannot be predicted. On the whole, the research that has been reported so far regarding road safety effects of porous asphalt is inconclusive. The studies are not of high quality and the findings are inconsistent.......This paper presents a systematic review of studies that have evaluated the effects on road safety of porous asphalt. Porous asphalt is widely used on motorways in Europe, mainly in order to reduce traffic noise and increase road capacity. A meta-analysis was made of six studies, containing a total...

  11. Performance on Water Stability of Cement-Foamed Asphalt Cold Recycled Mixture

    Directory of Open Access Journals (Sweden)

    Li Junxiao

    2018-01-01

    Full Text Available Through designing the mixture proportion of foamed asphalt cold in-place recycled mixture combined with the water stability experiment, it shows that the addition of cement can obviously improve foamed asphalt mixture’s water stability and the best cement admixture is between 1% ~ 2%; Using digital imaging microscope and SEM technology, the mechanism of increasing on the intensity of foamed asphalt mixture resulted by adding cement was analyzed. It revealed that the cement hydration products contained in the foamed asphalt mixture hydrolyzed into space mesh structure and wrapped up the aggregate particle, this is the main reason that the cement can enhance the mixture’s intensity as well as the water stability. This research provides reference for cement admixture’s formulation in the designing of foamed asphalt cold in-place recycled mixture.

  12. Design Method for Proportion of Cement-Foamed Asphalt Cold Recycled Mixture

    Directory of Open Access Journals (Sweden)

    Li Junxiao

    2018-01-01

    Full Text Available Through foaming experiment of Zhongtai AH-70 asphalt, the best foaming temperature water consumption and influence factors of foamed asphalt’s foaming features are determined; By designing the proportion of foamed asphalt cold in-place recycled mixture combined with the water stability experiment, for this mixture the best foamed asphalt addition is 3%, and proportion of the mixture is RAP: fine aggregate: cement=75:23:2. Using SEM technology, the mechanism of increasing on the intensity of foamed asphalt mixture resulted by the addition of cement was analysed. This research provides reference for cement admixture’s formulation in the designing of foamed asphalt cold in-place recycled mixture.

  13. Performance of asphaltic concrete incorporating styrene butadiene rubber subjected to varying aging condition

    Science.gov (United States)

    Salah, Faisal Mohammed; Jaya, Ramadhansyah Putra; Mohamed, Azman; Hassan, Norhidayah Abdul; Rosni, Nurul Najihah Mad; Mohamed, Abdullahi Ali; Agussabti

    2017-12-01

    The influence of styrene butadiene rubber (SBR) on asphaltic concrete properties at different aging conditions was presented in this study. These aging conditions were named as un-aged, short-term, and long-term aging. The conventional asphalt binder of penetration grade 60/70 was used in this work. Four different levels of SBR addition were employed (i.e., 0 %, 1 %, 3 %, and 5 % by binder weight). Asphalt concrete mixes were prepared at selected optimum asphalt content (5 %). The performance was evaluated based on Marshall Stability, resilient modulus, and dynamic creep tests. Results indicated the improving stability and permanent deformation characteristics that the mixes modified with SBR polymer have under aging conditions. The result also showed that the stability, resilient modulus, and dynamic creep tests have the highest rates compared to the short-term aging and un-aged samples. Thus, the use of 5 % SBR can produce more durable asphalt concrete mixtures with better serviceability.

  14. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

    International Nuclear Information System (INIS)

    Mahler, Barbara J.; Van Metre, Peter C.; Foreman, William T.

    2014-01-01

    Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement. - Highlights: • We compare PAH and azaarene concentrations in runoff from coal-tar- and asphalt-sealed pavement. • Concentrations in coal-tar-sealcoat runoff greatly exceeded those in asphalt-sealcoat runoff. • Decreases in azaarenes and LMW PAHs were offset by increases in HMW PAHs. • PAH concentrations in coal-tar-sealcoat runoff remained high for months after application. - Concentrations of PAHs in runoff from pavement with coal-tar-based sealcoat continue to be elevated for at least 3 months following sealcoat application

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-09-01

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

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

    International Nuclear Information System (INIS)

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

    1994-09-01

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

  17. International Conference on Category Theory

    CERN Document Server

    Pedicchio, Maria; Rosolini, Guiseppe

    1991-01-01

    With one exception, these papers are original and fully refereed research articles on various applications of Category Theory to Algebraic Topology, Logic and Computer Science. The exception is an outstanding and lengthy survey paper by Joyal/Street (80 pp) on a growing subject: it gives an account of classical Tannaka duality in such a way as to be accessible to the general mathematical reader, and to provide a key for entry to more recent developments and quantum groups. No expertise in either representation theory or category theory is assumed. Topics such as the Fourier cotransform, Tannaka duality for homogeneous spaces, braided tensor categories, Yang-Baxter operators, Knot invariants and quantum groups are introduced and studies. From the Contents: P.J. Freyd: Algebraically complete categories.- J.M.E. Hyland: First steps in synthetic domain theory.- G. Janelidze, W. Tholen: How algebraic is the change-of-base functor?.- A. Joyal, R. Street: An introduction to Tannaka duality and quantum groups.- A. Jo...

  18. Learnable Classes of Categorial Grammars.

    Science.gov (United States)

    Kanazawa, Makoto

    Learnability theory is an attempt to illuminate the concept of learnability using a mathematical model of learning. Two models of learning of categorial grammars are examined here: the standard model, in which sentences presented to the learner are flat strings of words, and one in which sentences are presented in the form of functor-argument…

  19. Language universals without universal categories

    NARCIS (Netherlands)

    Croft, W.; van Lier, E.

    2012-01-01

    In this article, the authors present their views on an article by author Sandra Chung related to lexical categories. According to them, Chung's article critiques an analysis of word classes in Chamorro by author Donald M. Topping. They discuss the restatements made by Chung on Topping's criteria for

  20. Auditory and phonetic category formation

    NARCIS (Netherlands)

    Goudbeek, Martijn; Cutler, A.; Smits, R.; Swingley, D.; Cohen, Henri; Lefebvre, Claire

    2017-01-01

    Among infants' first steps in language acquisition is learning the relevant contrasts of the language-specific phonemic repertoire. This learning is viewed as the formation of categories in a multidimensional psychophysical space. Research in the visual modality has shown that for adults, some kinds

  1. Recent rubber crumb asphalt pavement projects in Alberta

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

  2. Effect of crumb rubber on asphaltic binder chemistry and rheology

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Cicero de S.; Tome, Luisa G.A.; Sant' ana, Hosiberto B.; Soares, Jorge B.; Soares, Sandra A. [University Federal of Ceara, Fortaleza, CE (Brazil)

    2008-07-01

    The use of the crumb rubber (CR) from scraps tires to modify asphalt binders (AB) at high temperature can improve significantly the performance grade, but the storage stability can be influenced after the mix of AB and CR or polymer. The major concern of asphalt binder with polymer and CR blends is their lack of stability during prolonged storage at high temperatures. The tendency to phase separation under quiescent conditions appears as an important limitation for the practical use of these blends. After the RTFOT and PAV process, the binder conventional and modified was analyzed in a Fourier Transform Infrared spectrometer (FTIR) for chemical characterization. After aging in RTFOT, the AB presented a larger degradation compared to the CR of RABC and RABC commercial. So, the crumb rubber contributed to the binder stability, acting as an antioxidant in the aging process. The dynamic mechanical properties of CR modify asphalts binder before and after graft has been characterized by use of dynamic shear rheometer (DSR) or advances rheology expanded system (ARES) of Rheometric Scientific. The difference in the viscoelastic parameters between the top and the bottom sections of the tube was measured. It has been found that the added content of CR has great effect on the rheological properties of the AB and its high temperature performance. It also has been confirmed that the RABC sample showed larger storage stability compared to the sample RABC commercial observed with viscoelastic parameters. As a consequence, the use CR and aromatic oil can be considered a suitable alternative for modification of binder in pavement. (author)

  3. Weathering and decontamination of radioactivity deposited on asphalt surfaces

    International Nuclear Information System (INIS)

    Warming, L.

    1982-12-01

    Longlived fission products might be deposited in the environment after a serious reactor accident. At Risoe we have studied how danish weather conditions and fire hosing influence the decontamination of Rubidium 86 (representing Cesium 134 and 137) Barium-Lanthanum 140 and Ruthenium 103 deposited on asphalt surfaces. Measurements have been done at different types of roads and during all seasons including winter with snow and ice cover of the roads. The results from the first five experiments were used for calculating doses to the population in the land contamination (RISO-R-462). (author)

  4. Grammatical Constructions as Relational Categories.

    Science.gov (United States)

    Goldwater, Micah B

    2017-07-01

    This paper argues that grammatical constructions, specifically argument structure constructions that determine the "who did what to whom" part of sentence meaning and how this meaning is expressed syntactically, can be considered a kind of relational category. That is, grammatical constructions are represented as the abstraction of the syntactic and semantic relations of the exemplar utterances that are expressed in that construction, and it enables the generation of novel exemplars. To support this argument, I review evidence that there are parallel behavioral patterns between how children learn relational categories generally and how they learn grammatical constructions specifically. Then, I discuss computational simulations of how grammatical constructions are abstracted from exemplar sentences using a domain-general relational cognitive architecture. Last, I review evidence from adult language processing that shows parallel behavioral patterns with expert behavior from other cognitive domains. After reviewing the evidence, I consider how to integrate this account with other theories of language development. Copyright © 2017 Cognitive Science Society, Inc.

  5. A Formal Calculus for Categories

    DEFF Research Database (Denmark)

    Cáccamo, Mario José

    This dissertation studies the logic underlying category theory. In particular we present a formal calculus for reasoning about universal properties. The aim is to systematise judgements about functoriality and naturality central to categorical reasoning. The calculus is based on a language which...... extends the typed lambda calculus with new binders to represent universal constructions. The types of the languages are interpreted as locally small categories and the expressions represent functors. The logic supports a syntactic treatment of universality and duality. Contravariance requires a definition...... of universality generous enough to deal with functors of mixed variance. Ends generalise limits to cover these kinds of functors and moreover provide the basis for a very convenient algebraic manipulation of expressions. The equational theory of the lambda calculus is extended with new rules for the definitions...

  6. Seismic Category I Structures Program

    International Nuclear Information System (INIS)

    Endebrock, E.G.; Dove, R.C.; Anderson, C.A.

    1984-01-01

    The Seismic Category I Structures Program currently being carried out at the Los Alamos National Laboratory is sponsored by the Mechanical/Structural Engineering Branch, Division of Engineering Technology of the Nuclear Regulatory Commission (NRC). This project is part of a program designed to increase confidence in the assessment of Category I nuclear power plant structural behavior beyond the design limit. The program involves the design, construction, and testing of heavily reinforced concrete models of auxiliary buildings, fuel-handling buildings, etc., but doe not include the reactor containment building. The overall goal of the program is to supply to the Nuclear Regulatory Commission experimental information and a validated procedure to establish the sensitivity of the dynamic response of these structures to earthquakes of magnitude beyond the design basis earthquake

  7. Different Categories of Business Risk

    Directory of Open Access Journals (Sweden)

    Simona-Valeria TOMA

    2011-11-01

    Full Text Available Every business organisation involves some element of risk. Unmitigated risks can result in lost opportunity, financial losses, loss of reputation, or loss of the right to operate in a jurisdiction. Like any other risk type, understanding business risks is quite important for every business to garner profits instead of facing losses. A business risk is a universal risk type; this means that every business in the world faces business risks. Therefore, it is imperative to understand the different categories of business risk in order to create the appropriate strategies. The aim of this paper is to describe the most important categories of business risks and to make sure that every type of risk receives equal treatment and consideration.

  8. Virtue Ethics: The Misleading Category

    OpenAIRE

    Martha Nussbaum

    1998-01-01

    Virtue ethics is frequently considered to be a single category of ethical theory, and a rival to Kantianismand Utilitarianism. I argue that this approach is a mistake, because both Kantians and Utilitarians can, and do, have an interest in the virtues and the forrnation of character. But even if we focus on the group of ethical theorists who are most commonly called "virtue theorists" because they reject the guidance of both Kantianism and Utilitarianism, and derive inspiration from ancient G...

  9. Virtue Ethics: The Misleading Category

    OpenAIRE

    Nussbaum, Martha

    2013-01-01

    Virtue ethics is frequently considered to be a single category of ethical theory, and a rival to Kantianismand Utilitarianism. I argue that this approach is a mistake, because both Kantians and Utilitarians can, and do, have an interest in the virtues and the forrnation of character. But even if we focus on the group of ethical theorists who are most commonly called "virtue theorists" because they reject the guidance of both Kantianism and Utilitarianism, and derive inspiration from ancient G...

  10. 1999 who's who category index

    International Nuclear Information System (INIS)

    1999-01-01

    A classified index and alphabetical directory of Canadian corporate entities involved in the production, manufacturing, conversion, service, retail sales, research and development, transportation, insurance, legal and communications aspects of propane in Canada is provided. The alphabetical directory section provides the usual business information (name, postal address, phone, fax, e-mail and Internet addresses), names of principal officers, affiliations, products or services produced or marketed, and the category under which the company is listed in the classified index

  11. Experimental Investigation on Asphalt Binders Ageing Behavior and Rejuvenating Feasibility in Multicycle Repeated Ageing and Recycling

    Directory of Open Access Journals (Sweden)

    Yihua Nie

    2018-01-01

    Full Text Available Multicycle repeated utilization of reclaimed asphalt pavement (RAP is a quite recent development of sustainable pavement materials technology. To investigate ageing rules and recycling possibility of asphalt binders in repeatedly used asphalt mixture, virgin asphalt AH-70 samples were heated by the rolling thin film oven test (RTFOT at 163°C, respectively, for 40, 85, 180, 240, and 300 minutes to simulate different ageing degrees, and then the aged ones were rejuvenated by adding a self-made rejuvenator. This ageing and recycling process was repeated altogether for 5 cycles to simulate repeated use of RAP binders. In repeated recycling, rejuvenator contents for different cycle numbers or ageing durations were not the same, and the optimum ones were initially estimated by an empirical formula and finally obtained by comparative tests. Empirical rheological tests and the infrared spectral (IR analysis were done before and after each cycle of recycling. Results indicate that for impact on deterioration of asphalt binders, ageing time is more important than cycle number. Meanwhile, the asphalt after multicycle repeated ageing and recycling can be restored to the empirical rheological indices level of the virgin asphalt and meet specifications requirements.

  12. 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.

  13. A Study of Moisture Damage in Plastomeric Polymer Modified Asphalt Binder Using Functionalized AFM Tips

    Directory of Open Access Journals (Sweden)

    Rafiqul Tarefder

    2011-12-01

    Full Text Available In this study, moisture damage in plastomeric polymer modified asphalt binder is investigated using Atomic Force Microscopy (AFM with chemically functionalized AFM tips. Four different percentages of plastomeric polymers and two antistripping agents such as Kling Beta and Lime are used to modify a base asphalt binder. Chemical functional groups such as -COOH, -CH3, -NH3, and –OH, that are commonly present in plastomeric polymer modified asphalt system, are used to functionalize the AFM tips. The force distance mode of AFM is used to measure the adhesion forces between a modified asphalt sample surface and the functionalized AFM tips. This enables the measurement of adhesion within an asphalt binder system. It is shown that the adhesion force values in dry sample changed substantially from that in wet conditioned samples. It is evident from this study that plastomeric modification does not help reduce moisture damage in asphalt. The percentage change in adhesion forces due to moisture is about 20 nN for the lime modified samples, and about 50 nN for the Kling Beta modified samples. This indicates that lime is more effective than Kling Beta for reducing moisture damage in plastomeric polymer modified asphalt.

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

    Directory of Open Access Journals (Sweden)

    A.M.M. Abd El Rahman

    2012-12-01

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

  15. Rutting and Fatigue Cracking Resistance of Waste Cooking Oil Modified Trinidad Asphaltic Materials

    Directory of Open Access Journals (Sweden)

    Rean Maharaj

    2015-01-01

    Full Text Available The influence of waste cooking oil (WCO on the performance characteristics of asphaltic materials indigenous to Trinidad, namely, Trinidad Lake Asphalt (TLA, Trinidad Petroleum Bitumen (TPB, and TLA : TPB (50 : 50 blend, was investigated to deduce the applicability of the WCO as a performance enhancer for the base asphalt. The rheological properties of complex modulus (G∗ and phase angle (δ were measured for modified base asphalt blends containing up to 10% WCO. The results of rheology studies demonstrated that the incremental addition of WCO to the three parent binders resulted in incremental decreases in the rutting resistance (decrease in G∗/sinδ values and increases in the fatigue cracking resistance (decrease in G∗sinδ value. The fatigue cracking resistance and rutting resistance for the TLA : TPB (50 : 50 blends were between those of the blends containing pure TLA and TPB. As operating temperature increased, an increase in the resistance to fatigue cracking and a decrease in the rutting resistance were observed for all of the WCO modified asphaltic blends. This study demonstrated the capability to create customized asphalt-WCO blends to suit special applications and highlights the potential for WCO to be used as an environmentally attractive option for improving the use of Trinidad asphaltic materials.

  16. An Image-Based Finite Element Approach for Simulating Viscoelastic Response of Asphalt Mixture

    Directory of Open Access Journals (Sweden)

    Wenke Huang

    2016-01-01

    Full Text Available This paper presents an image-based micromechanical modeling approach to predict the viscoelastic behavior of asphalt mixture. An improved image analysis technique based on the OTSU thresholding operation was employed to reduce the beam hardening effect in X-ray CT images. We developed a voxel-based 3D digital reconstruction model of asphalt mixture with the CT images after being processed. In this 3D model, the aggregate phase and air void were considered as elastic materials while the asphalt mastic phase was considered as linear viscoelastic material. The viscoelastic constitutive model of asphalt mastic was implemented in a finite element code using the ABAQUS user material subroutine (UMAT. An experimental procedure for determining the parameters of the viscoelastic constitutive model at a given temperature was proposed. To examine the capability of the model and the accuracy of the parameter, comparisons between the numerical predictions and the observed laboratory results of bending and compression tests were conducted. Finally, the verified digital sample of asphalt mixture was used to predict the asphalt mixture viscoelastic behavior under dynamic loading and creep-recovery loading. Simulation results showed that the presented image-based digital sample may be appropriate for predicting the mechanical behavior of asphalt mixture when all the mechanical properties for different phases became available.

  17. Caltrans use of scrap tires in asphalt rubber products: a comprehensive review

    Directory of Open Access Journals (Sweden)

    Haiping Zhou

    2014-02-01

    Full Text Available The California Department of Transportation (Caltrans has been using scrap tire rubber in asphalt pavements since the 1970s in chip seals and the 1980s in rubberized hot mix asphalt(RHMA. Both the wet (field blend and dry processes were used in early trials. Caltrans has also used rubber modified binders containing both crumb rubber modifier and polymer modifier that could be manufactured at a refinery facility, a terminal blend wet process. Since the beginning of this century, Caltrans increased the use of scrap tire rubber in paving projects and invested considerable resources in developing technically sound, cost effective, and environmentally friendly strategies for using scrap tire rubber in roadway applications. By the end of year 2010, approximately 31%of all hot mix asphalt (HMA placed by Caltrans was rubberized HMA, roughly 1.2 million tons. Caltrans efforts in using asphalt rubber products were also demonstrated in its research and technology development. These included the construction of two full-scale field experiments, five warranty projects, and an accelerated pavement study using a heavy vehicle simulator. Additionally, terminal blend asphalt rubber and rubberized warm mix asphalts began to be experimented on trial basis. This paper provides a comprehensive review of Caltrans experience over four decades with asphalt rubber products. Current practices and future outlook are also discussed.

  18. Developing the elastic modulus measurement of asphalt concrete using the compressive strength test

    Science.gov (United States)

    Setiawan, Arief; Suparma, Latif Budi; Mulyono, Agus Taufik

    2017-11-01

    Elastic modulus is a fundamental property of an asphalt mixture. An analytical method of the elastic modulus is needed to determine the thickness of flexible pavement. It has a role as one of the input values on a stress-strain analysis in the finite element method. The aim of this study was to develop the measurement of the elastic modulus by using compressive strength testing. This research used a set of specimen mold tool and Delta Dimensi software to record strain changes occurring in the proving ring of compression machine and the specimens. The elastic modulus of the five types of aggregate gradation and 2 types of asphalt were measured at optimum asphalt content. Asphalt Cement 60/70 and Elastomer Modified Asphalt (EMA) were used as a binder. Manufacturing success indicators of the specimens used void-in-the-mix (VIM) 3-5 % criteria. The success rate of the specimen manufacturing was more than 76%. Thus, the procedure and the compressive strength test equipment could be used for the measurement of the elastic modulus. The aggregate gradation and asphalt types significantly affected the elastic modulus of the asphalt concrete.

  19. Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China.

    Science.gov (United States)

    Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

    2016-03-22

    In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase.

  20. PROSPECTS FOR APPLICATION OF COMPLEX-MODIFIED SAND ASPHALT CONCRETE IN ROAD CONSTRUCTION

    Directory of Open Access Journals (Sweden)

    D. Yu. Alexandrov

    2017-01-01

    Full Text Available The paper considers a possibility to use sand asphalt concrete as a material for protection of asphalt concrete and cement concrete road pavements against affection of external destructive factors. Advantages and disadvantages of sand asphalt concrete road pavements have been determined in the paper. The paper provides recommendations on improvement of sand asphalt concrete properties and contains an analysis of possible variants for usage of complex-modified sand asphalt concrete in the road construction. It has been noted that according to its potentially possible physical and mechanical properties activated quartz sand being micro-reinforced by dispersive industrial wastes is considered as an efficient component for creation of constructive layers in road asphalt concrete pavements. The paper reveals only specific aspects of the efficient application of quartz sand in road asphalt concrete. The subject of the paper loоks rather interesting for regions where there are no rock deposits for obtaining broken-stone ballast but there is rather significant spreading of local quarts sand. Its successful application is connected with the necessity to develop special equipment for physical and chemical activation of sand grain surface that permits strongly to increase an adhesive strength in the area of phase separation within the “bitumen–SiO2” system. The considered problem is a topical one and its solution will make it possible to local sand in a maximum way and partially to exclude application of broken stone in road construction.

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

    Directory of Open Access Journals (Sweden)

    Yongchun Cheng

    2015-01-01

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

  2. Organic Tracers from Asphalt in Propolis Produced by Urban Honey Bees, Apis mellifera Linn.

    Science.gov (United States)

    Alqarni, Abdulaziz S; Rushdi, Ahmed I; Owayss, Ayman A; Raweh, Hael S; El-Mubarak, Aarif H; Simoneit, Bernd R T

    2015-01-01

    Propolis is a gummy material produced by honey bees to protect their hives and currently has drawn the attention of researchers due to its broad clinical use. It has been reported, based only on observations, that honey bees also collect other non-vegetation substances such as paint or asphalt/tar to make propolis. Therefore, propolis samples were collected from bee hives in Riyadh and Al-Bahah, a natural area, Saudi Arabia to determine their compositional characteristics and possible sources of the neutral organic compounds. The samples were extracted with hexane and analyzed by gas chromatography-mass spectrometry. The results showed that the major compounds were n-alkanes, n-alkenes, methyl n-alkanoates, long chain wax esters, triterpenoids and hopanes. The n-alkanes (ranging from C17 to C40) were significant with relative concentrations varying from 23.8 to 56.8% (mean = 44.9+9.4%) of the total extracts. Their odd carbon preference index (CPI) ranged from 3.6 to 7.7, with a maximum concentration at heptacosane indicating inputs from higher plant vegetation wax. The relative concentrations of the n-alkenes varied from 23.8 to 41.19% (mean = 35.6+5.1%), with CPI = 12.4-31.4, range from C25 to C35 and maximum at tritriacontane. Methyl n-alkanoates, ranged from C12 to C26 as acids, with concentrations from 3.11 to 33.2% (mean = 9.6+9.5%). Long chain wax esters and triterpenoids were minor. The main triterpenoids were α- and β-amyrins, amyrones and amyryl acetates. The presence of hopanes in some total extracts (up to 12.5%) indicated that the bees also collected petroleum derivatives from vicinal asphalt and used that as an additional ingredient to make propolis. Therefore, caution should be taken when considering the chemical compositions of propolis as potential sources of natural products for biological and pharmacological applications. Moreover, beekeepers should be aware of the proper source of propolis in the flight range of their bee colonies.

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

    International Nuclear Information System (INIS)

    García, Alvaro; Partl, Manfred N.

    2014-01-01

    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

  4. Influence of Temperature Upon Permanent Deformation Parameters of Asphalt Concrete Mixes

    Directory of Open Access Journals (Sweden)

    Amjad Hamad Albayati

    2017-07-01

    Full Text Available The performance of asphalt concrete pavement has affected by many factors, the temperature is the most important environmental one which has a large effect on the structural behavior of flexible pavement materials. The main cause of premature failure of pavement is the rutting, Due to the viscoelastic nature of the asphalt cement, rutting is more pronounced in hot climate areas because the viscosity of the asphalt binder which is inversely related to rutting is significantly reduced with the increase in temperature resulting in a more rut susceptible paving mixtures. The objective of this study is to determine the effect of temperatures variations on the permanent deformation parameters (permanent strain (p, intercept (a, slope (b, Alpha and Mu as well as resilient strain (r and resilient modulus (Mr. To achieve this objective, one aggregate gradation with 12.5mm nominal maximum size, two grades of asphalt cements (40-50 and 60-70 brought form Al- Daurah refinery, limestone dust filler has been used to prepare the asphalt concrete mixtures. 30 Marshall specimens were prepared to determine the optimum asphalt cement content. Thereafter, 30 cylindrical asphalt concrete specimens (102mm in diameter and 203 mm in height are prepared in optimum asphalt cement and optimum ±0.5 percent. The prepared specimens were used in uniaxial repeated load test to evaluate the permanent deformation parameters of asphalt concrete mixes under the following testing temperature (5, 15, 25, 40 and 60c. The test result analyses appeared that Mr is decrease 51 percent when temperature increased from 5 c to 25 c and then decrease 22 percent with further increase in temperature from 25 c to 60 c. Also, the Alpha value decreases by a factor of 1.25 and 1.13 when temperature increases from 5 c to 25 c and 25 c to 60 c, espectively. Finally, statistical models were developed to predict the Alpha and Mu parameters of permanent deformation.

  5. Test of cold asphalt storability based on alternative approaches

    Science.gov (United States)

    Abaffyová, Zora; Komačka, Jozef

    2017-09-01

    Cold asphalt products for potholes repairs should be workable (soft enough) for long time to ensure their applicability. Storability is assessed indirectly using various tests of workability. Therefore, simple test methods (self-compaction and disintegration test) was developed and verified to investigate changes of storability of this group of cold asphalts. Selfcompaction of the tested mixture in the upturned Abram’s cone for the cement concrete slump test and in the mould for the California Bearing Ratio test was assessed in first stage. After that the video record of disintegration test was taken. During this test, the mould was lifted up and the mixture fell off the mould (Abram’s cone) or disintegrate (CBR mould). The drop of surface after 10 min self-compaction and netto time related to falling out or disintegration of the mixture were used to evaluate the mixture from storability point of view. It was found out the self-compaction test has not a potential to reveal and prove changes of mixture properties. Based on the disintegration test results it can be stated this test at 5 °C using the upturned Abram’s cone could be a suitable approach to determine qualitative changes of a cold mixture from storability point of view.

  6. Determination of Stone-Mastic Asphalt Concrete Durability

    Science.gov (United States)

    Yastremsky, D. A.; Abaidullina, T. N.; Chepur, P. V.

    2018-05-01

    The paper is focused on determination of durability of the stone-mastic asphalt (SMA) concrete, containing various stabilizing additives: "Armidon" (authors’ development) and "Viatop". At the first stage of experiments, the APA method was used to determine the rutting in the SMA containing these additives. Strength test for only top layers of asphalt concrete surface is insufficient for the calculation of the pavement fatigue resistance limits. Due to this fact, a comprehensive approach was employed which incorporates the interaction of the surface and subgrade natural soil. To analyze the road surface stress-strain state and to determine the durability margin, a numerical model was used (describes the processes of fatigue life). The model was developed basing on the finite element method (FEM) in the ANSYS program. Conducted studies and numerical calculations allowed obtaining the minimum and maximum stress values in the structure affected zones and in the zones of plastic deformations occurrence in artificial and natural bases. It allows predicting deformation processes during repeated wheel loads caused by moving vehicles. In course of studies, the results of static stresses in the pavement were also obtained.

  7. Stormwater Pollution Prevention Plan - TA-60 Asphalt Batch Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-31

    This Storm Water Pollution Prevention Plan (SWPPP) was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. §§1251 et seq., as amended), and the Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity (U.S. EPA, June 2015) issued by the U.S. Environmental Protection Agency (EPA) for the National Pollutant Discharge Elimination System (NPDES) and using the industry specific permit requirements for Sector P-Land Transportation and Warehousing as a guide. This SWPPP applies to discharges of stormwater from the operational areas of the TA-60-01 Asphalt Batch Plant at Los Alamos National Laboratory. Los Alamos National Laboratory (also referred to as LANL or the “Laboratory”) is owned by the Department of Energy (DOE), and is operated by Los Alamos National Security, LLC (LANS). Throughout this document, the term “facility” refers to the TA-60 Asphalt Batch Plant and associated areas. The current permit expires at midnight on June 4, 2020.

  8. Choosing mineral carrier of nanoscale additives for asphalt concrete

    Directory of Open Access Journals (Sweden)

    Inozemtsev Sergey Sergeevich

    2014-03-01

    Full Text Available At present time the operation life of the majority of roads is essentially shorter than required. The reason for it is the increase in traffic intensity and axle loads of automobile transport. The obvious reasons for early wear of roads are the low quality of the components used and low industrial standards while producing asphalt pavement. In this paper the mineral material was selected as a carrier of nanoscale additives for asphalt. The optimal modes for grinding mineral materials were identified, which provide correspondence of their structure parameters with the developed model. The influence of different mineral nanomodifier carriers on the structure formation processes was estimated. It is shown that among a number of mineral materials diatomite has high activity in relation to the bitumen, because it has a highly porous structure. It is also shown that as a result of lighter fractions of bitumen adsorption on the border of phase interface, diatomite and bitumen changes from the free state to the film, and solvate shell of bitumen is saturated with asphaltenes. With the help of IR spectroscopy the authors defined the nature of the diatomite and bitumen interaction and proved that in the process of their interaction there occurs physical adsorption with additional absorption of bitumen components into the pore space of diatomite grains.

  9. Group type analysis of asphalt by column liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C.; Yang, J.; Xue, Y.; Li, Y. [Chinese Academy of Science, Taiyuan (China)

    2008-07-01

    An improved analysis method for characterization of asphalt was established. The method is based on column chromatography technique. The asphalts were separated into four groups: saturates, aromatics, resins, and asphaltenes, quantitatively. About 0.1 g of sample was required in each analysis. About 20 mL of n-heptanes was used to separate out saturates first. Then about 35 mL of n-heptanes/dichloromethane (.5, v/v) mixture was used to separate out aromatics. About 30 mL of dichloromethane/tetrahydrofuran (1/3, v/v) mixture was used to separate out resin. The quality of the separation was confirmed by infrared spectra (IR) and {sup 1}H NMR analysis. The model compounds, tetracosan for saturates, dibenz(o)anthracen for aromatics, and acetanilide for resins were used for verification. The IR and {sup 1}H NMR analysis of the prepared fractions from the column liquid chromatography were in good agreement that of pure reagents.

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

    KAUST Repository

    Juristyarini, Pramitha; Davison, Richard R.; Glover, Charles J.

    2011-01-01

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

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

    KAUST Repository

    Juristyarini, Pramitha

    2011-09-07

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

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

    Science.gov (United States)

    Park, Philip

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

  13. A category of its own?

    DEFF Research Database (Denmark)

    Elklit, Jørgen; Roberts, Nigel S.

    1996-01-01

    of these systems on the proportionality of the representation of political parties are, indeed, comparable. The four electoral systems were the basis of their countries' general elections during 1994. The results of these elections are used for analyses and discussions of the relative importance of the differences......At first sight, the electoral systems in Denmark, Germany, South Africa and Sweden may seem different and attaempt to categorize them together odd. All four, however, belong to the same category, which Arend Lijphart calls 'proportional representation two-tier districting systems', and the effects...

  14. Functional categories in comparative linguistics

    DEFF Research Database (Denmark)

    Rijkhoff, Jan

    , Roger M. 1979. Linguistic knowledge and cultural knowledge: some doubts and speculation. American Anthropologist 81-1, 14-36. Levinson, Stephen C. 1997. From outer to inner space: linguistic categories and non-linguistic thinking. In J. Nuyts and E. Pederson (eds.), Language and Conceptualization, 13......). Furthermore certain ‘ontological categories’ are language-specific (Malt 1995). For example, speakers of Kalam (New Guinea) do not classify the cassowary as a bird, because they believe it has a mythical kinship relation with humans (Bulmer 1967).       In this talk I will discuss the role of functional...

  15. 14 CFR 23.3 - Airplane categories.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Airplane categories. 23.3 Section 23.3... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES General § 23.3 Airplane categories. (a) The normal category is limited to airplanes that have a seating configuration, excluding pilot...

  16. Aspect as a Communicative Category

    DEFF Research Database (Denmark)

    Durst-Andersen, Per

    2018-01-01

    On the basis of internal evidence from primarily the use of imperfective forms and external evidence from primarily first language acquisition, it is argued that English, Russian, and French aspect differ from one another, because they go back to an obligatory choice among three possible communic......On the basis of internal evidence from primarily the use of imperfective forms and external evidence from primarily first language acquisition, it is argued that English, Russian, and French aspect differ from one another, because they go back to an obligatory choice among three possible...... communicative directions: should a grammatical category be grounded in the speaker's experience of a situation, in the situation referred to or in the hearer as information about the situation? The progressive vs. non-progressive distinction in English is acquired in the present tense of atelic (simplex) verbs...... to the meta-distinction between atelic (simplex) and telic (complex) verbs. It is second-person oriented. The specific order arrived at reflects the Peircean categories of Firstness, Secondness, and Thirdness and their predictions. This can account for the fact that the English and Russian types can be found...

  17. Effect of tack coat on bonding characteristics at interface between asphalt concrete layers; Asphalt concrete no sokan fuchaku ni okeru tack concrete no koka

    Energy Technology Data Exchange (ETDEWEB)

    Hachiya, Y. [Port and Harbour Research Inst., Kanagawa (Japan); Umeno, S. [Ministry of Transport, Tokyo (Japan); Sato, K. [Nagaoka National College of Technology, Niigata (Japan)

    1997-08-20

    The effect of tack coat on bonding characteristics at the interface between surface and base layers was studied for airport asphalt pavement. In a fracture behavior, shear stress is first caused by horizontal loading at the interface between surface and base layers, resulting in peeling of the layers in the case of poor bonding. Further loading under the above condition results in fracture of asphalt concrete layers by bending or tensile actions. The bonding strength between layers decreases with an increase in interval of construction between surface and base layers, while the bonding strength between layers increases with sufficient curing of tack coat. Curing for 1 hour in the daytime and 6 hours or more in the nighttime is sufficient for evaporation of water content in asphalt emulsion. The use of conventional asphalt emulsion for the sandy interface as tack coat deduces the bonding strength in the case of poor curing. Asphalt emulsion containing high-penetration rubber can improve the bonding strength. 12 refs., 27 figs., 2 tabs.

  18. A Review on Using Crumb Rubber in Reinforcement of Asphalt Pavement

    Science.gov (United States)

    Mashaan, Nuha Salim; Ali, Asim Hassan; Karim, Mohamed Rehan; Abdelaziz, Mahrez

    2014-01-01

    An immense problem affecting environmental pollution is the increase of waste tyre vehicles. In an attempt to decrease the magnitude of this issue, crumb rubber modifier (CRM) obtained from waste tyre rubber has gained interest in asphalt reinforcement. The use of crumb rubber in the reinforcement of asphalt is considered as a smart solution for sustainable development by reusing waste materials, and it is believed that crumb rubber modifier (CRM) could be an alternative polymer material in improving hot mix asphalt performance properties. In this paper, a critical review on the use of crumb rubber in reinforcement of asphalt pavement will be presented and discussed. It will also include a review on the effects of CRM on the stiffness, rutting, and fatigue resistance of road pavement construction. PMID:24688369

  19. Mechanical Properties of Portland Cement Concrete With Recycled Asphalt Pavement as Partial Replacement for Coarse Aggregate

    Science.gov (United States)

    2016-06-01

    Finding constructive uses for construction waste byproducts contributes to green engineering principles. One such plentiful material is recycled asphalt pavement (RAP). This report looks at the mechanical viability of including RAP in a high strength...

  20. Implementation of transverse variable asphalt rate seal coat practices in Texas.

    Science.gov (United States)

    2011-01-01

    An implementation project was performed to expand use of transversely varied asphalt rate (TVAR) seal : coat practices in all districts. The project included nine regional workshops, continued field texture testing of : test sites, provided one set o...

  1. Optimization of Asphalt Mixture Design for the Louisiana ALF Test Sections

    Science.gov (United States)

    2018-05-01

    This research presents an extensive study on the design and characterization of asphalt mixtures used in road pavements. Both mixture volumetrics and physical properties obtained from several laboratory tests were considered in optimizing the mixture...

  2. Determination of the biodegradation rate of asphalt for the Hanford grout vaults

    International Nuclear Information System (INIS)

    Luey, J.; Li, S.W.

    1993-04-01

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

  3. Electrical deicing utilizing carbon fiber tape for asphalt approach and crosswalk phase I - literature review.

    Science.gov (United States)

    2016-06-30

    The purpose of this study is to provide a comprehensive literature review of electrical deicing technology for possible application in asphalt approach and crosswalks. A : thorough review of existing and emerging deicing technology for snow/ice melti...

  4. A simple test procedure for evaluating low temperature crack resistance of asphalt concrete : executive summary report.

    Science.gov (United States)

    2009-03-01

    Low temperature cracking is one of the major : distress modes in asphalt pavement and is : disastrous to pavement performance and service : life. A poor riding surface leads to an increase in : maintenance and eventual early replacement of : the pave...

  5. Validity of multiple stress creep recovery (MSCR) test for DOTD asphalt binder specification : final report 564.

    Science.gov (United States)

    2017-09-01

    Numerous studies have shown that G*/Sin, the high temperature specification parameter for current Performance Graded (PG) asphalt binder is not adequate to reflect the rutting characteristics of polymer-modified binders. Consequently, many state De...

  6. Non-destructive system to evaluate critical properties of asphalt compaction : [research brief].

    Science.gov (United States)

    2013-12-01

    The Wisconsin Highway Research Program sponsored a two-stage investigation to develop a non-destructive system to evaluate critical compaction properties and characteristics of asphalt pavements during the densification process. Stage One activities ...

  7. Unsaturated zone moisture and vapor movement induced by temperature variations in asphalt barrier field lysimeters

    International Nuclear Information System (INIS)

    Holford, D.J.; Fayer, M.J.

    1990-08-01

    Protective barriers are being considered for use at the Hanford Site to enhance the isolation of radioactive wastes from water, plant, and animal intrusion. Lysimeters were constructed to evaluate the performance of asphalt barrier formulations under natural environmental conditions. These lysimeters were constructed of 1.7-m lengths of PVC pipe that have a diameter of 30 cm. The lysimeters were filled with layers of gravel, coarse sand, and asphalt. The sand and gravel placed under the asphalt barrier were wet when installed. TOUGH was used to conduct simulations to assess the effect of temperature variations on moisture and vapor movement beneath the asphalt layer in field test lysimeters. All variables in TOUGH were converted to double precision so that simulations could be run on a Sun-4 UNIX workstation. A radially symmetric grid was used to simulate the lysimeter. 8 refs., 9 figs

  8. Mechanistic Evaluation of the Effect of Calcium Carbide Waste on Properties of Asphalt Mixes

    Directory of Open Access Journals (Sweden)

    N. Isa

    2018-03-01

    Full Text Available Calcium Carbide Waste (CCW was used as an alternative to traditional Portland cement mineral filler in hot mix asphalt concrete to rid its disposal problem. Its effect on mechanical properties of hot mix asphalt was assessed using the Marshall method of mix design. Using the optimum bitumen content determined from Marshall Test, Portland cement used as mineral filler was partially replaced with 0, 10, 20, 30, 40 and 50% CCW by dry weight. Results of tests indicated an increase in stability, voids in mineral aggregates, Marshall Stiffness and reduction in flow, unit weight, voids filled with binder when the percentage of CCW increases. Based on results of tests, partial replacement of Portland cement with 40% CCW could be used in asphalt production. This will ensure economy in asphalt production and promote disposal of CCW which constitute environmental hazards.

  9. Effect of nanosilica particles on polypropylene polymer modified asphalt mixture performance

    Directory of Open Access Journals (Sweden)

    Nura Bala

    2018-06-01

    Full Text Available The current study was conducted to investigate the effect of nanosilica particles on the performance characteristics of polymer modified asphalt binders. In this study, control 80/100 binder were modified with polypropylene polymer and nanosilica particles at concentration of 0%–4%. Both nanosilica particles and polypropylene polymer were added by weight of total bitumen content. The asphalt performance tests flexural four point beam fatigue test, indirect tensile strength, indirect tensile stiffness modulus and draindown tests are conducted to evaluate the effect of nanosilica particles. The results of the study shows that nanosilica particles improves the fatigue properties of polypropylene polymer modified binder. This indicates that nanosilica particles have significant effect on improving the performance properties of polymer modified binders. Also, the result reveals that thermoplastic polymer polypropylene with nanosilica particles when used as bitumen modifiers improve the performance and durability of asphalt mixtures. Keywords: Polypropylene, Fatigue cracking, Stiffness modulus, Modified asphalt, Draindown

  10. A Mechanistic Design Approach for Graphite Nanoplatelet (GNP) Reinforced Asphalt Mixtures for Low-Temperature Applications

    Science.gov (United States)

    2018-01-01

    This report explores the application of a discrete computational model for predicting the fracture behavior of asphalt mixtures at low temperatures based on the results of simple laboratory experiments. In this discrete element model, coarse aggregat...

  11. A study of the influence of coarse aggregate shape characteristics on permanent deformation of asphalt mixes

    CSIR Research Space (South Africa)

    Mabuse, MM

    2013-07-01

    Full Text Available The effect of aggregate shape properties such as angularity, texture, sphericity, roundness, flat and elongation on the performance of asphalt mixes have not been thoroughly investigated using direct measurement techniques. This is partly because...

  12. Evaluation of moisture damage in asphalt concrete with CRM motorcycle tire waste passing #50 sieve size

    Science.gov (United States)

    Siswanto, Henri; Supriyanto, Bambang; Pranoto, Pranoto; Chandra, Pria Rizky; Hakim, Arief Rahman

    2017-09-01

    The objective of this experimental research is to evaluate moisture damage in Asphalt Concrete (AC) with Crumb Rubber Modified (CRM) motorcycle tire waste passing #50 and retaining #100 sieve size. Two gradations were used in this research, the first gradation is usual for asphalt concrete base (ACB) and the second gradation is for asphalt concrete wearing course (ACWC). Marshall testing apparatus was used for testing the Marshall specimens. Seven levels of CRM content were used, namely 0%, 0.5%, 1%, 1.5%, 3%, 4.5% and 6% by weight of mixtures. Retained stability represent the level of moisture damage of AC pavement. The result indicates that addition CRM to the AC mixture increases their the stability to a maximum value and subsequent addition decrease the stability. The addition CRM to AC decreases their moisture damage susceptibility. AC with 1% CRM is the best asphalt-CRM mix.

  13. Use of moisture induced stress testing to evaluate stripping potential of hot mix asphalt (HMA).

    Science.gov (United States)

    2012-07-01

    Stripping of hot mix asphalt (HMA) in the field is an ongoing issue for many Departments of Transportation : (DOTs). A leading cause of stripping is hydraulic scouring. The Moisture Induced Stress Tester (MIST) is a recently : developed technology th...

  14. Recycled Asphalt Pavement and Crushed Concrete Backfill: State-of-the-Art Review and Material Characterization

    Science.gov (United States)

    2001-10-01

    This report describes research results from the first year of a three-year study focused on the use of recycled asphalt pavement (RAP) and crushed concrete (CC) as backfill for mechanically stabilized earth (MSE) walls.

  15. Installation report : evaluation of recycled hot mix asphaltic concrete on Route 220.

    Science.gov (United States)

    1982-01-01

    This report describes a project in which the bituminous pavement on an approximately 8-mi. (13-km) section of roadway was removed, recycled through a conventional asphalt batch plant, and relaid. The project was accomplished with little difficulty an...

  16. Quality control/quality assurance testing for joint density and segregation of asphalt mixtures.

    Science.gov (United States)

    2013-04-01

    Longitudinal joint quality control/assurance is essential to the successful performance of asphalt pavements and it has received considerable amount of attention in recent years. The purpose of the study is to evaluate the level of compaction at the ...

  17. Effects of Test Conditions on APA Rutting and Prediction Modeling for Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2017-01-01

    Full Text Available APA rutting tests were conducted for six kinds of asphalt mixtures under air-dry and immersing conditions. The influences of test conditions, including load, temperature, air voids, and moisture, on APA rutting depth were analyzed by using grey correlation method, and the APA rutting depth prediction model was established. Results show that the modified asphalt mixtures have bigger rutting depth ratios of air-dry to immersing conditions, indicating that the modified asphalt mixtures have better antirutting properties and water stability than the matrix asphalt mixtures. The grey correlation degrees of temperature, load, air void, and immersing conditions on APA rutting depth decrease successively, which means that temperature is the most significant influencing factor. The proposed indoor APA rutting prediction model has good prediction accuracy, and the correlation coefficient between the predicted and the measured rutting depths is 96.3%.

  18. A comparative analysis of modified binders : original asphalts and materials extracted from existing pavements : technical summary.

    Science.gov (United States)

    2010-01-01

    The initial objective of this research was to develop procedures and standards for applying GPC as an analytical tool to define the percentage amounts of polymer modifiers in polymer modified asphalt cements soluble in eluting GPC solvents. Quantific...

  19. The effects of coarse aggregate cleanliness and moisture content on asphalt concrete compactability and moisture susceptibility.

    Science.gov (United States)

    2011-12-31

    Twelve field projects were studied where forty-four locations were evaluated to assess the cause or : causes of asphalt concrete that exhibits tender zone characteristics (i.e. instability during compaction) and to : investigate the tendency of...

  20. Improving DMS 9210 requirements for limestone rock asphalt : year one interim report.

    Science.gov (United States)

    2013-05-01

    Limestone Rock Asphalt (LRA) mixtures have been produced and placed for several decades using specification requirements currently listed under DMS 9210. Several Districts have had placement issues and premature failures at the beginning of 2010. The...