Verification of Mechanistic Prediction Models for Permanent Deformation in Asphalt Mixes Using Accelerated Pavement Testing - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Verification of Mechanistic Prediction Models for Permanent Deformation in Asphalt Mixes Using Accelerated Pavement Testing write by Mbakisya A. Onyango. This book was released on 2009. Verification of Mechanistic Prediction Models for Permanent Deformation in Asphalt Mixes Using Accelerated Pavement Testing available in PDF, EPUB and Kindle. Permanent deformation (rutting) is the most critical load-associated distress that develops on asphalt pavements significantly affecting their performance. Past research work focused on estimating permanent deformation of asphalt mixes using empirical prediction models or prediction models based on linear elastic material models. In recent years, mechanistic and mechanistic-empirical prediction models have been developed to take into account the behavior of asphalt material (viscoelastic, viscoplastic or elasto-visco-plastic). This research project aims to evaluate existing mechanistic models that predict permanent deformation (rutting) in asphalt mixes by comparing computed permanent deformation to that measured in a full-scale accelerated pavement test. Six pavement sections were constructed in the Civil Infrastructure Systems Laboratory (CISL) of Kansas State University with six different asphalt mixes. The sections were loaded with up to 700,000 load repetitions of a 22,000lb single axle. The transverse profiles at the pavement surface were measured periodically. For material characterization, asphalt mix samples fabricated in the laboratory, were subjected to dynamic modulus (E*), static creep - flow time (Ft), dynamic creep - flow number (Fn), triaxial and uniaxial strength tests, repetitive shear at constant height (RSCH) and frequency sweep at constant height (FSCH). The finite element software, Abaqus, was used to simulate and evaluate four permanent deformation prediction models, which are: creep model, elasto-visco-plastic model, viscoelastic model and Drucker-Prager model. The predicted permanent deformation was then compared to permanent deformation measured in CISL for the six of asphalt pavement sections. It was found that, with some improvements, creep and elasto-visco-plastic models could be used to predict permanent deformation in asphalt mixes. The viscoelastic model greatly under-predict permanent deformation, and the Drucker-Prager model with hardening criteria over predicts permanent deformation as compared to values measured in CISL.
Advances in Pavement Design through Full-scale Accelerated Pavement Testing
Advances in Pavement Design through Full-scale Accelerated Pavement Testing - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Advances in Pavement Design through Full-scale Accelerated Pavement Testing write by David Jones. This book was released on 2012-10-08. Advances in Pavement Design through Full-scale Accelerated Pavement Testing available in PDF, EPUB and Kindle. Pack: Book and CDInternationally, full-scale accelerated pavement testing, either on test roads or linear/circular test tracks, has proven to be a valuable tool that fills the gap between models and laboratory tests and long-term experiments on in-service pavements. Accelerated pavement testing is used to improve understanding of pavement behavior,
Development and Validation of Performance Prediction Models and Specifications for Asphalt Binders and Paving Mixes
Development and Validation of Performance Prediction Models and Specifications for Asphalt Binders and Paving Mixes - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Development and Validation of Performance Prediction Models and Specifications for Asphalt Binders and Paving Mixes write by Robert L. Lytton. This book was released on 1993. Development and Validation of Performance Prediction Models and Specifications for Asphalt Binders and Paving Mixes available in PDF, EPUB and Kindle. A result of the Strategic Highway Research Program's asphalt research is the development of performance-based specifications for asphalt binders and mixtures to control 3 distress modes: rutting; fatigue cracking; and thermal cracking. The SHRP A-005 project developed detailed pavement performance models to support these binder and mixture specifications and performance-based mixture designs. This report documents the findings of this extensive research effort and provides supporting data for the performance-based specifications and mixture design procedure called SUPERPAVE. The A-005 contract developed and used a sophisticated, mechanistic-based pavement performance model to define the relationships between asphalt binder and mixture properties and pavement distress. A comprehensive pavement performance model was developed that predicts the amount of fatigue cracking, thermal cracking and rutting in asphalt concrete pavements with time, using results from the accelerated laboratory tests. The pavement performance models for each distress were also used to confirm the relevant binder and mixture properties established by other SHRP contractors. The model has 3 parts: a mixture evaluation model; a pavement response model; and a pavement distress model.
Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing
Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing write by Feng Hong. This book was released on 2009. Calibrating Mechanistic-Empirical Design Guide Permanent Deformation Models Based on Accelerated Pavement Testing available in PDF, EPUB and Kindle. One of the challenges to the implementation of the mechanistic-empirical pavement design guide (MEPDG) comes from calibrating the transfer functions. This paper focuses on calibration of one of the major distress models in flexible pavement: permanent deformation or rutting. Two key aspects are critical to a successful rutting model calibration: data and method. Regarding the data, existing in-field information only provides total rut depth, which could not meet the requirement of permanent deformation in each structural layer by the MEPDG. Concerning the method, existing work either fails to address calibration factors from a holistic perspective by only focusing on individual sections separately or ignores variability inherent in those factors. In this study, layer-wise permanent deformation from instrumented pavement under accelerated pavement testing serves to accommodate the models calibration. A systematic calibration procedure is established, which globally optimizes all available information across all test sections. Through simulation and numerical optimization, optimal calibration shift factors for three typical flexible pavement materials, asphalt mixture, unbound granular base, and finegrain soil are obtained as 0.60, 0.49, and 0.84, respectively. This implies that the uncalibrated MEPDG is biased toward overprediction of rut depth. It is further suggested that a more rational result for each calibrated factor is to introduce an appropriate distribution to characterize its uncaptured variability. In addition, a case study involving using calibrated MEPDG to predict pavement performance or life indicates that (1) model calibration has a significant impact on the prediction and (2) the "fourth power law" is supported by the MEPDG.
Significant Findings from Full-scale Accelerated Pavement Testing
Significant Findings from Full-scale Accelerated Pavement Testing - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Significant Findings from Full-scale Accelerated Pavement Testing write by Wynand JvdM. Steyn. This book was released on 2012. Significant Findings from Full-scale Accelerated Pavement Testing available in PDF, EPUB and Kindle. "TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 433: Significant Findings from Full-Scale Accelerated Pavement Testing documents and summarizes significant findings from the various experimental activities associated with full-scale accelerated pavement testing (f-sAPT) programs that have taken place between 2000 and 2011. The report also identifies gaps in knowledge related to f-sAPT and where future research may be needed. NCHRP Synthesis 433 is designed to expand the f-sAPT base of knowledge documented in NCHRP Syntheses 325 and 235, both with the same title of Significant Findings from Full-Scale Accelerated Pavement Testing. f-sAPT is the controlled application of a wheel loading, at or above the appropriate legal load limit, to a pavement system to determine pavement response in a compressed time period. The acceleration of damage is achieved by one or more of the following factors: increased repetitions, modified loading conditions, imposed climatic conditions, and thinner pavements with a decreased structural capacity which have shorter design lives"--
