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 Engineering Properties of Asphalt Mixtures and the Relationship to Their Performance written by Gerald A. Huber and published by ASTM International. This book was released on 1995 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thirteen papers presented at the conference on [title], held in Phoenix, Arizona, December, 1994, discuss the products of the strategic highway research program, the Superpave method of mix design, and test methods for fatigue cracking and permanent deformation. Lacks an index. Annotation c. by Book

Download or read book Permanent Deformation Characteristics of Recycled Asphalt Concrete Mixes written by and published by . This book was released on 1987 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various blends of recovered and virgin asphalt cement were tested for properties including penetration, absolute and kinematic viscosity and water susceptibility. conventional marshall tests were also performed, and permanent strain characteristics were measured by repeated load triaxial tests. the test results show that inclusion of reclaimed material in amounts as low as 30 percent can reduce the permanent strain values significantly. a regression model has been developed to relate permanent strain to the number of load repetitions, to predict permanent deformation under various mix and environmental conditions. for the covering abstract of the conference see irrd 807058.

Download or read book An Evaluation of Permanent Deformation Properties of Crumb Rubber Modified CRM Asphalt Concrete Mixtures written by Danai Ellarin Makunike and published by . This book was released on 1995 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Permanent Deformation Response of Asphalt Aggregate Mixes written by Christine W. Curtis and published by National Research Council. This book was released on 1994 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the research conducted on permanent deformation of asphalt concrete mixes as part of the SHRP Asphalt Research Program. Divided into three sections the report addresses the following: the development of a series of accelerated performance tests to measure the permanent deformation response and a constitutive relationship to define it; validation of the binder properties included in the SHRP binder specification; and the use of the test methodology in an asphalt concrete mix design and analysis system.

Download or read book Impact of Variations in Material Properties on Asphalt Pavement Life Final Report written by P. Puangchit and published by . This book was released on 1982 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Implication of Aggregates in the Design Construction and Performance of Flexible Pavements written by Hans G. Schreuders and published by ASTM International. This book was released on 1989 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Properties of Flexible Pavement Materials written by John J. Emery and published by ASTM International. This book was released on 1983 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Permanent Deformation of Asphalt Mixtures written by Patrick Mwangi Muraya and published by . This book was released on 2016-04-22 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Evaluation of Permanent Deformation and Low Temperature Characteristics of Some Recycled Asphalt Concrete Mixtures written by and published by . This book was released on 1988 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Viscoelastic and Permanent Deformation Characteristics of Asphalt Aggregate Mixes Tested as Hollow Cylinders and Subjected to Dynamic Axiel and Shear Loads written by Sirous Heydari Alavi and published by . This book was released on 1992 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mix Design and Engineering Properties of Large aggregate Bituminous Concrete written by Craig M. Newtson and published by . This book was released on 1992 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Permanent Deformation of Asphalt Concrete Pavements written by Fenella Margaret Long and published by . This book was released on 2001 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Viscoelastic Fatigue Damage and Permanent Deformation Characterization of High Rap Bituminous Mixtures Using Fine Aggregate Matrix FAM written by Hesamaddin Nabizadeh and published by . This book was released on 2015 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: Performance characteristics of bituminous mixtures play the most influential role in designing flexible pavement. These asphaltic mixtures can be considered as heterogeneous mixtures which composed of two primary components: fine aggregate matrix (FAM) phase and aggregate phase. The FAM phase acts as a critical phase in evaluating the performance characteristics including viscoelastic, fatigue damage, and permanent deformation characteristics of entire asphalt mixtures. This study evaluates the viscoelastic, fatigue damage and permanent deformation characteristics of bituminous mixtures containing 65% reclaimed asphalt pavement (RAP) by performing oscillatory torsional shear tests of cylindrical bars of FAM using a dynamic mechanical analyzer. Moreover, this study investigates a linkage between performance characteristics of asphalt concrete (AC) mixture and its corresponding FAM phase. To meet the objectives of this study, laboratory tests were performed for several FAM mixtures with 65% reclaimed asphalt pavement and different types of rejuvenators and one warm mix asphalt (WMA) additive. Test results were then analyzed using viscoelastic theories and fatigue prediction models based on continuum damage mechanics. Furthermore, obtained laboratory test results were compared with corresponding test results of asphalt concrete mixtures. The test results indicated that rejuvenators change properties and performance behavior related to fatigue damage and permanent deformation of high reclaimed asphalt pavement mixtures. In addition, test results of FAM phase were generally linked well with asphalt concrete mixture test results, and they vividly depicted that FAM phase could provide core information to predict the behavior of the asphalt concrete mixture.

Download or read book Permanent Deformation Characteristics of Asphalt Concrete written by David Brian McLean and published by . This book was released on 1974 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summary Report on Permanent Deformation in Asphalt Concrete written by Jorge B. Sousa and published by . This book was released on 1990 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report evaluates information on the permanent deformation characteristics of asphalt-aggregate mixtures, with an emphasis on laboratory test techniques for measuring mixture resistance to permanent deformation, and on methods for prediction of permanent deformation (rutting) in the upper asphalt bound layers of pavements. Factors influencing the amount of rutting are summarized. The laboratory test methds associated with the predictive methodologies that are evaluated include: unaixial and creep tests; uniaxial and triaxial and repeated load test; triaxial dynamic tests; diametral tests, creep and repeated load tests; hollow cylinder tests, combined axial and torsional loading; simple shear tests, unconfined and confined; and wheel-track tests. From these evaluations, specific test methodologies are ranked in order of preference.

Download or read book Permanent Deformation Characteristics of Asphalt Mixtures by Repeated load Indirect Tensile Test written by Joaquín Vallejo and published by . This book was released on 19?? with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: