Download or read book Prediction of Fatigue Performance of Asphalt Concrete Mixes written by DV. Ramsamooj and published by . This book was released on 1999 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The suitability of dense-graded hot-mix asphalt concrete mixtures for fatigue-resistant flexible pavements is investigated. The fatigue lives of several mixes including those with additives of latex, rubber, and sulfur are predicted by a theory derived from fracture mechanics. There is good agreement between the model predictions for the fatigue lives and the experimental results for the laboratory tests. The material properties are then used to predict the fatigue performance of two of these mixes in a simulated full-depth flexible pavement and a three-layer flexible pavement. There is poor agreement between the model predictions for the performance of the simulated pavements and the laboratory tests. Several reasons are postulated for the differences in the fatigue lives for the laboratory beam tests and the simulated pavements.

Download or read book Fatigue Performance Prediction of North Carolina Mixtures Using Simplified Viscoelastic Continuum Damage Model written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue performance modeling is one the major topics in asphalt concrete modeling work. Currently the only standard fatigue test available for asphalt concrete mixtures is the flexural bending fatigue test, AASHTO T-321. There are several issues associated with flexural fatigue testing, the most important of which are the stress state is not uniform but varies over the depth of the specimen and equipment for fabricating beam specimens is not widely available. Viscoelastic continuum damage (VECD) fatigue testing is a promising alternative to flexural fatigue testing. Different researchers have successfully applied the VECD model to asphalt concrete mixtures using constant crosshead rate direct tension test. However, due to the load level limitation of the new coming Asphalt Mixture Performance Tester (AMPT) testing equipment, there is an immediate need to develop a model that can characterize fatigue performance quickly using cyclic test data. In this study, a simplified viscoelastic continuum damage model developed at NCSU is applied to various North Carolina mixtures, which are used in the NCDOT HWY-2007-7 MEPDG local calibration project. It is shown that the simplified VECD model can predict fatigue tests fairly accurately under various temperature conditions and strain levels. It is also shown that the model can be further utilized to simulate both the strain controlled direct tension fatigue test and the traditional beam fatigue test. In this thesis, simulation results are presented. Conclusions regarding the applicability of the new model are advanced as well as suggestions for further work.

Download or read book Preliminary Fatigue Analysis of a Common TxDOT Hot Mix Asphalt Concrete Mixture written by and published by . This book was released on 2005 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, the Texas Department of Transportation (TxDOT) focused research efforts on improving mixture design to preclude rutting in the early life of the pavement, which also offered increased resistance to moisture damage, but fatigue cracking may surface in the long term particularly if the binder stiffens excessively due to aging. The primary goal of this project is to evaluate and recommend a fatigue analysis system for TxDOT designs to ensure adequate mixture fatigue performance in a particular pavement structure under specific environmental and loading conditions. A secondary goal of comparing fatigue resistance of commonly used TxDOT mixtures including investigating the effects of aging will also be realized.

Download or read book A Phenomenological Fatigue Performance Model of Asphalt Mixtures Based on Fracture Energy Density written by A. M. Bahadori and published by . This book was released on 2014 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study the fatigue performance of asphalt mixtures was interpreted based on fracture energy density. Recent studies indicate that the fracture energy from indirect tension tests correlates with the field performance of asphalt concrete. The fracture energy density was obtained from indirect tensile strength tests, and the fatigue performance of asphalt mixtures was evaluated with four-point bending beam fatigue tests implemented at three different strain levels. Two different asphalt mixtures with varying binder contents were tested during this study. Test results showed that the fracture energy density could be an appropriate material property in phenomenological fatigue models. Thus a phenomenological fatigue model based on fracture energy density is presented, and this approach could be advantageous because a simple fatigue model based on fracture energy density does not require time-consuming fatigue tests. For comparison purposes, the various types of fatigue models were evaluated, and fatigue models based on fracture energy density and dissipated energy showed rather high prediction accuracy. In general, fatigue models based on the energy concept have the least dependence on material properties and can predict the fatigue lives of asphalt mixtures without changing coefficients.

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 Comparison of Fatigue Analysis Approaches for Predicting Fatigue Lives of Hot mix Asphalt Concrete HMAC Mixtures written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hot-mix asphalt concrete (HMAC) mixture fatigue characterization constitutes a fundamental component of HMAC pavement structural design and analysis to ensure adequate field fatigue performance. HMAC is a heterogeneous complex composite material of air, binder, and aggregate that behaves in a non-linear elasto-viscoplastic manner, exhibits anisotropic behavior, ages with time, and heals during traffic loading rest periods and changing environmental conditions. Comprehensive HMAC mixture fatigue analysis approaches that take into account this complex nature of HMAC are thus needed to ensure adequate field fatigue performance. In this study, four fatigue analysis approaches; the mechanistic empirical (ME), the calibrated mechanistic with (CMSE) and without (CM) surface energy measurements, and the proposed NCHRP 1-37A 2002 Pavement Design Guide (MEPDG) were comparatively evaluated and utilized to characterize the fatigue resistance of two Texas HMAC mixtures in the laboratory, including investigating the effects of binder oxidative aging. Although the results were comparable, the CMSE/CM approaches exhibited greater flexibility and potential to discretely account for most of the fundamental material properties (including fracture, aging, healing, visco-elasticity, and anisotropy) that affect HMAC pavement fatigue performance. Compared to the other approaches, which are mechanistic-empirically based, the CMSE/CM approaches are based on the fundamental concepts of continuum micromechanics and energy theory.

Download or read book Creep and Fatigue Characteristics of Superpave Mixtures written by Stacey D. Diefenderfer and published by . This book was released on 2005 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laboratory creep and fatigue testing was performed on five Superpave surface hot-mix asphalt mixtures placed at the Virginia Smart Road. Differences in creep and fatigue response attributable to production and compaction methods were investigated. In addition, changes in creep response resulting from differences in specimen size were evaluated. Further, an evaluation of the effects of loading frequency, presence of rest periods, and specimen location within the pavement on fatigue life was conducted. Creep compliance values were determined using viscoelastic-based calculations, and time-temperature superposition was used to generate mastercurves. Reported creep compliance response models from the literature were found inadequate for accurately describing the creep compliance mastercurves generated during this study. Differences in creep response between specimens of different sizes were found to be due to specimen and test variability, rather than size. An evaluation of the effects of laboratory and plant production and laboratory and field compaction was inconclusive as material variability appeared greater than production or compaction variability. Simple regression models were found to be satisfactory for use in the development of prediction models for fatigue, although test data are necessary for calibration to particular mixture types. No relationships were found between fatigue model coefficients and volumetric properties of the mixtures tested because of the limited range of volumetric properties. Variability in volumetric properties between the mixtures produced at the plant and those produced to match the job mix formula did not significantly influence the predicted laboratory fatigue performance. Laboratory fatigue lives were similar between the laboratory-compacted fatigue specimens and specimens cut from the pavement; differences observed in performance were attributable to different air void contents. Predicted fatigue life was found to be statistically independent of the frequency of the applied loads or presence of rest periods for the mixtures, frequencies, and rest periods considered in this study. Minimal differences were observed between fatigue life predictions for plant-produced, field-compacted specimens cut from different locations in the pavement. This study contributes to the understanding of the factors involved in creep and fatigue performance of asphalt mixtures. The mixture responses characterized by this study are related to the rutting and fatigue performance of asphalt pavements. The choice of appropriate asphalt materials to resist rutting and fatigue deterioration will result in reduced maintenance needs and longer service lives for pavements.

Download or read book Fatigue Performance of Asphalt Concrete Mixes and Its Relationship to Asphalt Concrete Pavement Performance in California written by and published by . This book was released on 1995 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Materials and Pavement Performance Prediction II written by K. Anupam and published by CRC Press. This book was released on 2020-12-08 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inspired from the legacy of the previous four 3DFEM conferences held in Delft and Athens as well as the successful 2018 AM3P conference held in Doha, the 2020 AM3P conference continues the pavement mechanics theme including pavement models, experimental methods to estimate model parameters, and their implementation in predicting pavement performance. The AM3P conference is organized by the Standing International Advisory Committee (SIAC), at the time of this publication chaired by Professors Tom Scarpas, Eyad Masad, and Amit Bhasin. Advances in Materials and Pavement Performance Prediction II includes over 111 papers presented at the 2020 AM3P Conference. The technical topics covered include: - rigid pavements - pavement geotechnics - statistical and data tools in pavement engineering - pavement structures - asphalt mixtures - asphalt binders The book will be invaluable to academics and engineers involved or interested in pavement engineering, pavement models, experimental methods to estimate model parameters, and their implementation in predicting pavement performance.

Download or read book Two Stage Weibull Approach for Asphalt Concrete Fatigue Performance Prediction written by and published by . This book was released on 2004 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Developments in Pavement Design Modeling and Performance written by Sherif El-Badawy and published by Springer. This book was released on 2018-10-30 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume includes a collection of research and practical papers from an international research and technology activities on recent developments in pavement design, modeling and performance, and effects on infrastructure, green energy, technology and integration. Sustainability is increasingly a key priority in engineering practices. With the aging transportation infrastructure and renewed emphasis on infrastructure renovation by transportation agencies, innovations are urgently needed to develop materials, designs, and practices to ensure the sustainability of transportation infrastructure. The volume is based on the best contributions to the 2nd GeoMEast International Congress and Exhibition on Sustainable Civil Infrastructures, Egypt 2018 – The official international congress of the Soil-Structure Interaction Group in Egypt (SSIGE).

Download or read book Development of Equipment and Techniques for Evaluating Fatigue and Rutting Characteristics of Asphalt Concrete Mixes written by Richard D. Barksdale and published by . This book was released on 1977 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of an Image based Multi scale Finite Element Approach to Predict Fatigue Damage in Asphalt Mixtures written by and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Image-based simulation of complex materials is a very important tool for understanding their mechanical behavior and an effective tool for successful design of composite materials. In this thesis an image-based multi-scale finite element approach is developed to predict the mechanical properties of asphalt mixtures. In this approach the "up-scaling" and homogenization of each scale to the next is critically designed to improve accuracy. In addition to this multi-scale efficiency, this study introduces an approach for consideration of particle contacts at each of the scales in which mineral particles exist. One of the most important pavement distresses which seriously affects the pavement performance is fatigue cracking. As this cracking generally takes place in the binder phase of the asphalt mixture, the binder fatigue behavior is assumed to be one of the main factors influencing the overall pavement fatigue performance. It is also known that aggregate gradation, mixture volumetric properties, and filler type and concentration can affect damage initiation and progression in the asphalt mixtures. This study was conducted to develop a tool to characterize the damage properties of the asphalt mixtures at all scales. In the present study the Viscoelastic continuum damage model is implemented into the well-known finite element software ABAQUS via the user material subroutine (UMAT) in order to simulate the state of damage in the binder phase under the repeated uniaxial sinusoidal loading. The inputs are based on the experimentally derived measurements for the binder properties. For the scales of mastic and mortar, the artificially 2-Dimensional images of mastic and mortar scales were generated and used to characterize the properties of those scales. Finally, the 2D scanned images of asphalt mixtures are used to study the asphalt mixture fatigue behavior under loading. In order to validate the proposed model, the experimental test results and the simulation results were compared. Indirect tensile fatigue tests were conducted on asphalt mixture samples. A comparison between experimental results and the results from simulation shows that the model developed in this study is capable of predicting the effect of asphalt binder properties and aggregate micro-structure on mechanical behavior of asphalt concrete under loading

Download or read book Prediction of Fatigue Life of Asphalt Concrete Beams from Fracture Tests written by DV. Ramsamooj and published by . This book was released on 1991 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: A substantial amount of experimental data is presented to verify a theoretical solution for predicting the fatigue life of asphalt concrete beams from fracture tests. The theory utilizes the principles of fracture mechanics and covers the full range of loading from low to high. The raw test data extracted from a report by Majidzadeh et al. [1] include dynamic modulus, ultimate tensile strength, critical stress-intensity factor, and fatigue life of asphalt concrete beams fabricated from over 46 different mixtures, consisting of three types of asphalts, five asphalt contents, three filler asphalt ratios, and several gradations. The fracture and fatigue tests were also conducted on one asphalt concrete mix at temperatures ranging from 16 to 35°C (35 to 95°F). The agreement between theory and experiment is excellent.

Download or read book Fatigue Performance of Asphalt Concrete Mixes Using a New Repetitife sic Direct Tension Test written by Shakir R. Shatnawi and published by . This book was released on 1997 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper evaluates the fatigue performance of several asphalt concrete field mixes using a newly developed repetitive direct tension test that utilizes the uniaxial testing principles and fits into the Superpave shear tester. The device was used to conduct frequency sweep tests in compression and in tension, and fatigue tests in the tension mode of loading only. In addition, shear frequency sweep tests were conducted.

Download or read book Simple Indexes to Identify Fatigue Performance of Asphalt Concrete written by Xuan Chen and published by . This book was released on 2020 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using indexes based on engineering properties is among the ways to evaluate the quality of an asphalt concrete mix in terms of its resistance to fatigue cracking. These indexes typically are developed based on measuring asphalt concrete or asphalt binder properties in a laboratory test. Among such tests, the semicircular bend (SCB) test has shown potential as a promising test to determine fatigue resistance of asphalt mixtures. In the work presented, this test was explored extensively to determine proper fatigue performance identifiers from the test. Numerous tests were conducted to determine the effect of asphalt mix composition on the SCB fatigue test results. A major index considered from this test for evaluation is the flexibility index (FI), which is defined as the ratio of fracture energy and the post peak slope at inflection point derived from a typical load-deformation or stress-strain monotonic test. This index has been proposed based on extensive research at the University of Illinois. In the work presented in this study, tests were conducted on both short- and long-term aged asphalt mixes to evaluate FI and its reliability as a fatigue resistance indicator. The mix components considered as test variables included binder content, air void, and binder stiffness. The results showed a significant reduction in FI fatigue resistance after long term aging. Reduced FI is believed to associate with reduced fatigue life. The sensitivity of FI and other engineering properties to mix parameters were investigated in this research. It was found that FI could not be used alone and as a sole indicator of fatigue performance. It was determined that two indexes are needed for this purpose the first presents the mix toughness and ductility, and the second is a strength- or stiffness-based index.

Download or read book Comparison of Fatigue Analysis Approaches for Two Hot Mix Asphalt Concrete HMAC Mixtures written by and published by . This book was released on 2005 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, the Texas Department of Transportation (TxDOT) focused research efforts on improving mixture design to preclude rutting in the early life of the pavement. However, these rut resistant stiff mixtures may be susceptible to long-term fatigue cracking in the pavement structure as the binder stiffens due to oxidative aging. To address this concern, TxDOT initiated a research study with the primary goal of evaluating and recommending a hot mix asphalt concrete (HMAC) mixture fatigue design and analysis system to ensure adequate mixture fatigue performance in a particular pavement structure under specific environmental and traffic loading conditions. A secondary goal of the research was to compare the fatigue resistance of commonly used TxDOT HMAC mixtures including investigating the effects of binder aging on fatigue performance.