Download or read book Comparing the Volumetric and Mechanical Properties of Laboratory and Field Specimens of Asphalt Concrete written by Louay Nadhim Mohammad and published by . This book was released on 2016 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reports document research that was performed to (1) determine causes of variability and tolerances for volumetric and mechanical properties of dense-graded asphalt mixtures measured within and among the three specimen types; and (2) propose a practice for state departments of transportation to incorporate these results in specifications and criteria for quality assurance, mix design verification or validation, and structural design and forensic studies. The research was conducted in two phases. In Phase I, datasets of laboratory and field test data were collected and pooled in a meta-analysis in an attempt to determine levels of variability in asphalt mixtures and the factors causing variability among and between the three specimen types. Despite the inclusion of 25 extensive datasets representing roughly 8,000 individual mixtures in the meta-analysis, the results of the analysis were inconclusive. Phase II was then undertaken—a program testing specimens from paving projects across the United States to quantify the effects of process-based factors on the variability of volumetric and mechanical properties of the specimen types. The key outcome of the research is a proposed practice for evaluating the cause and magnitude of variability within and among the three specimen types. In addition, tolerances of volumetric and conversion factors between the three specimen types of mechanical properties evaluated are proposed based on the average difference between specimen comparisons for the mixtures evaluated in Phase II. Agencies may use these proposed values to evaluate and adjust their current tolerances.

Download or read book Comparing the Volumetric and Mechanical Properties of Laboratory and Field Specimens of Asphalt Concrete written by Louay Nadhim Mohammad and published by . This book was released on 2016 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reports document research that was performed to (1) determine causes of variability and tolerances for volumetric and mechanical properties of dense-graded asphalt mixtures measured within and among the three specimen types; and (2) propose a practice for state departments of transportation to incorporate these results in specifications and criteria for quality assurance, mix design verification or validation, and structural design and forensic studies. The research was conducted in two phases. In Phase I, datasets of laboratory and field test data were collected and pooled in a meta-analysis in an attempt to determine levels of variability in asphalt mixtures and the factors causing variability among and between the three specimen types. Despite the inclusion of 25 extensive datasets representing roughly 8,000 individual mixtures in the meta-analysis, the results of the analysis were inconclusive. Phase II was then undertaken--a program testing specimens from paving projects across the United States to quantify the effects of process-based factors on the variability of volumetric and mechanical properties of the specimen types. The key outcome of the research is a proposed practice for evaluating the cause and magnitude of variability within and among the three specimen types. In addition, tolerances of volumetric and conversion factors between the three specimen types of mechanical properties evaluated are proposed based on the average difference between specimen comparisons for the mixtures evaluated in Phase II. Agencies may use these proposed values to evaluate and adjust their current tolerances.

Download or read book Asphaltic Concrete Construction written by National Research Council (U.S.). Highway Research Board and published by . This book was released on 1960 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paper 1: The broad gap between research on asphaltic concrete specimens prepared in laboratory bench-type equipment and test roads or public highways has been narrowed by providing full-scale paving equipment in a research facility. This facility permits asphaltic concrete pavement construction under conditions of control which cannot be reached in field operations. Paper 2: Laboratory and field data have been collected from 12 regular contract hot-mix asphaltic concrete paving projects in various areas of Texas for the purpose of comparing laboratory and field densities. Paper 3 proposes a mechanism by which mixes can be unstable at high temperatures during rolling and still be quite stable by normal design criteria.

Download or read book Report written by and published by . This book was released on 1964 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of the Moisture Susceptibility of WMA Technologies written by Amy Epps Martin and published by Transportation Research Board. This book was released on 2014 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: "TRB's National Cooperative Highway Research Program (NCHRP) Report 763: Evaluation of the Moisture Susceptibility of WMA Technologies presents proposed guidelines for identifying potential moisture susceptibility in warm mix asphalt (WMA). The report also suggests potential revisions to the Appendix to AASHTO R 35, "Special Mixture Design Considerations and Methods for WMA" as a means to implement the guidelines."--publisher's description

Download or read book Evaluation of Gap graded Asphalt Concrete Mixtures written by Dah-yinn Lee and published by . This book was released on 1973 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents the results of a comparative laboratory study between well-graded and gap-graded aggregates used in asphalt concrete paving mixtures. There was a total of 424 batches of asphalt concrete mixtures and 3,960 Marshall and Hveem specimens. There is strong evidence from this investigation that, with proper combinations of aggregates and asphalts, both continuous and gap-graded aggregates can produce mixtures of high density and of qualities meeting current design criteria. There is also reason to believe that the unqualified acceptance of some supposedly desirable, constant, mathematical relationship between adjacent particle sizes of the form such as Fuller's curve is not justified. It is recommended that the aggregate grading limits be relaxed or eliminated and that the acceptance or rejection of an aggregate to be used in asphalt pavement be based on individual mixture evaluation. Furthermore, because of the potential attractiveness of gap-graded asphalt concrete in cost, quality, skid and wear resistance, and construction, selected gap-gaded mixtures are recommended for further tests both in the laboratory and in the field, especially in regard to ease of compaction and skid and wear resistance.

Download or read book Sustainable Designed Pavement Materials Volume 2 written by Yue Xiao and published by MDPI. This book was released on 2020-12-06 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue “Sustainable Designed Pavement Materials” has been proposed and organized as a means to present recent developments in the field of environmentally-friendly designed pavement materials. For this reason, articles included in this special issue relate to different aspects of pavement materials, from industry solid waste recycling to pavement materials recycling, from pavement materials modification to asphalt performance characterization, from pavement defect detection to pavement maintenance, and from asphalt pavement to cement concrete pavement.

Download or read book Bearing Capacity Of Roads written by A. Gomes Correia and published by CRC Press. This book was released on 2020-12-17 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an outcome of the sixth conference on bearing capacity of roads and airfield held in Lisbon, Portugal. It covers the following topics: bearing capacity policies, concepts, costs and condition surveys; analysis and modelling; design and environmental effects; and asphalt mixtures.

Download or read book Laboratory Tests for Hot mix Asphalt Characterization in Virginia written by and published by . This book was released on 2005 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project reviewed existing laboratory methods for accurately describing the constitutive behavior of the mixes used in the Commonwealth of Virginia. Indirect tensile (IDT) strength, resilient modulus, static creep in the IDT and uniaxial modes, flexural beam fatigue, and dynamic modulus tests were conducted on two typical mixes used in Virginia: SM-9.5A (surface mix) and BM-25.0 (base mix). The tests conducted produced a wealth of data on typical values for the properties of the two mixes studied over a wide range of temperatures and loading frequencies. The results suggest that the IDT strength test is an effective test to characterize the tensile strength of hot-mix asphalt (HMA), especially for thermal cracking evaluation. The resilient modulus test and the static creep test in the IDT setup are practical and simple to perform, but the analysis of the measurements is complicated, and the variability of the results is high. The compressive uniaxial dynamic modulus and the uniaxial static creep tests were found to be simple to conduct and to analyze because of the homogeneous state of stress in the specimen during testing. The flexural fatigue test was time consuming, but the test produces valuable information about the fatigue properties of hot-mix asphalt. The investigation also found good correlations among the IDT strength, resilient modulus, and dynamic modulus results. A variety of tests is recommended for characterizing the mechanistic-empirical pavement analysis and design. These tests would provide the properties needed to characterize the asphalt layers for the pavement analysis and design. The recommended tests are as follows: IDT strength for characterizing HMA susceptibility to thermal cracking, dynamic modulus for characterization of the constitutive behavior of the HMA, uniaxial creep for characterizing permanent deformation characteristics, and flexural fatigue tests to characterize fatigue properties. Materials characterization testing can be a valuable tool in pavement design. The use of mechanistic-empirical modeling can be used to predict the performance of a pavement. With this type of testing and modeling, the materials used in pavements will be of better quality and more resistant to environmental and structural deterioration. A more durable pavement will aid in reducing the frequency and costs associated with maintenance.

Download or read book Asphalt aggregate Mixture Analysis System AAMAS written by National Research Council (U.S.). Transportation Research Board and published by Transportation Research Board. This book was released on 1991 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Compare In situ Strength of Asphalt Concrete Treated Base written by California. Office of Transportation Laboratory and published by . This book was released on 1974 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Low Temperature Cracking in Asphalt Pavement Mixes written by Khaled Ksaibati and published by . This book was released on 1998 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report examines the feasibility of using the thermal stress restrained specimen test to evaluate low temperature cracking in asphalt pavement mixes. Data were collected from laboratory and field evaluations. Various mixing, aging, and compaction methods were used to prepare test samples with materials obtained from two Wyoming Department of Transportation (WYDOT) highway projects. Field data were obtained from two recently built test sections and compared with laboratory test results. Pavement condition surveys quantified low temperature cracking of both test sections after one winter. Temperature data for the project sites also were collected. Pavement condition and temperature data were compared to results from the thermal stress restrained specimen test. The thermal stress restrained specimen test was effective in testing asphalt pavement mixes. However, test results indicated that lab prepared samples did not closely simulate field samples. Also, comparisons of lab results with field conditions were performed. However, it is recommended that a more comprehensive analysis be performed after test sections have been in service for a few years.

Download or read book AASHTO Guide for Design of Pavement Structures 1993 written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 1993 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.

Download or read book Advances in Asphalt Emulsion Materials for Cold Paving Technologies written by Jian Ouyang and published by Frontiers Media SA. This book was released on 2020-12-22 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.

Download or read book Permanent Deformation Properties of Asphalt Concrete Mixtures written by Rabbira Garba and published by . This book was released on 2002 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rutting is recognized to be the major distress mechanism in flexible pavements as a result of increase in tire pressures and axle loads. Rutting is caused by the accumulation of permanent deformation in all or some of the layers in the pavement structure. The accumulation of permanent deformation in the asphalt surfacing layer is now recognized to be the major component of rutting in flexible pavements. This is a consequence of increased tire pressures and axle loads, which subjects the asphalt surfacing layer nearest to the tire-pavement contact area to increased stresses. Thus the study of permanent deformation properties of asphalt mixtures has become the focus of research, which aim to mitigate or reduce rutting in flexible pavements. The research work reported in this thesis aims to contribute towards understanding of the material properties and factors affecting permanent deformation in asphalt mixtures, mechanisms of the permanent deformation, and methods of its prediction. The specific objectives of this research work include; review and evaluation of available models for permanent deformation of asphalt concrete mixtures, investigation of the effect of volumetric composition, loading and temperature conditions on the permanent deformation of asphalt concrete, and the identification and definition of simple measures of resistance to permanent deformation. To meet the objectives of the study a laboratory investigation is conducted on several asphalt concrete specimens with varying volumetric composition. Two testing procedures are adopted; the repeated load triaxial and triaxial creep and recovery tests. The tests were conducted at two temperature levels of 25 and 50oC under varying stress conditions. A review of literature on factors affecting permanent deformation and available models for prediction of the permanent deformation is also conducted. The literature review indicated that most of the research work done so far concentrated on evaluation of the effect on permanent deformation response of component material properties such as aggregate gradation, aggregate angularity and binder type (or grade). Most of the studies conducted on permanent deformation properties of asphalt mixtures were also found to be based on different testing procedures and methods of evaluation, which makes it difficult to compare them and draw firm conclusions. The literature also indicated that, as yet, there is no comprehensive model for deformation of asphalt concrete. Results of tests conducted in this study are analysed to investigate the effect of volumetric composition, particularly binder content and void content, and loading conditions on the permanent deformation response of the mixture. Both the binder content and void content are found to significantly influence the permanent deformation characteristics. The effect of loading conditions, i.e., the confining stress and the deviatoric stress, is also found to be significant. Throughout this study emphasis is placed on methods and parameters that are used to evaluate mixtures for their resistance to permanent deformation. The traditionally used parameters such as the slope and intercept of the power model are evaluated for their sensitivities to changes in volumetric composition. This evaluation is based on the premises that any measure of resistance to permanent deformation should be sensitive to changes in volumetric composition to be good enough. It is found that most of these parameters are not sensitive to changes in volumetric composition and therefore are not suitable for comparison of mixtures made from the same materials but with varying proportion of the components. Permanent deformation in asphalt concrete is caused by both densification and shear deformation. The mode of deformation in asphalt concrete pavements, for greater part of their service life, is considered to be the shear deformation. Therefore it is necessary to evaluate mixtures for their susceptibility to shear deformation. The shear deformation manifests itself in the form of large lateral deformation relative to axial deformation. It is found that one dimensional analysis, which does not take the lateral deformation into account may lead to misleading results regarding the resistance to permanent deformation of mixtures. Therefore parameters which include volumetric and lateral strain are proposed for use in evaluation of mixtures. Substantial effort is put into modelling the accumulation of permanent deformation under repeated loading. For this purpose two approaches were selected: the cyclic hardening model based on bounding surface plasticity concept and an elasto-viscoplastic model based on strain decomposition approach. The bounding surface plasticity approach is found to be a convenient method to model the accumulation of permanent deformation. It is demonstrated that deformations calculated using cyclic hardening model based on bounding surface plasticity fits the measured deformation quite well. The elasto-viscoplastic model, which is based on strain decomposition approach, provides a suitable method for analysis of creep and recovery test results. Deformations calculated using this model also fit the measured deformation quite well. Finally a new composite measure of resistance to permanent deformation is developed. The resistance index is based on strain decomposition approach and is simple to calculate. The index incorporates a parameter related to shear susceptibility of mixtures and is sensitive to changes in volumetric composition. It is believed that this index can be used to compare and select mixtures at mixture design stage. If its applicability to other materials is proved by further research, it can also be linked to performance related specifications, as a simple measure of performance with regard to rutting.

Download or read book Bearing Capacity of Roads Railways and Airfields written by Andreas Loizos and published by CRC Press. This book was released on 2017-07-20 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bearing Capacity of Roads, Railways and Airfields includes the contributions to the 10th International Conference on the Bearing Capacity of Roads, Railways and Airfields (BCRRA 2017, 28-30 June 2017, Athens, Greece). The papers cover aspects related to materials, laboratory testing, design, construction, maintenance and management systems of transport infrastructure, and focus on roads, railways and airfields. Additional aspects that concern new materials and characterization, alternative rehabilitation techniques, technological advances as well as pavement and railway track substructure sustainability are included. The contributions discuss new concepts and innovative solutions, and are concentrated but not limited on the following topics: · Unbound aggregate materials and soil properties · Bound materials characteritics, mechanical properties and testing · Effect of traffic loading · In-situ measurements techniques and monitoring · Structural evaluation · Pavement serviceability condition · Rehabilitation and maintenance issues · Geophysical assessment · Stabilization and reinforcement · Performance modeling · Environmental challenges · Life cycle assessment and sustainability Bearing Capacity of Roads, Railways and Airfields is essential reading for academics and professionals involved or interested in transport infrastructure systems, in particular roads, railways and airfields.

Download or read book Recent Advances in Material Manufacturing and Machine Learning written by Rajiv Gupta and published by CRC Press. This book was released on 2023-05-26 with total page 793 pages. Available in PDF, EPUB and Kindle. Book excerpt: The role of manufacturing in a country’s economy and societal development has long been established through their wealth generating capabilities. To enhance and widen our knowledge of materials and to increase innovation and responsiveness to ever-increasing international needs, more in-depth studies of functionally graded materials/tailor-made materials, recent advancements in manufacturing processes and new design philosophies are needed at present. The objective of this volume is to bring together experts from academic institutions, industries and research organizations and professional engineers for sharing of knowledge, expertise and experience in the emerging trends related to design, advanced materials processing and characterization, and advanced manufacturing processes.