Comparison of Fatigue Cracking Performance of Asphalt Pavements Predicted by Pavement ME and LVECD Programs

Abstract

Mechanistic–empirical pavement design has received significant attention from the pavement community as the method for designing asphalt pavements in the future. Currently available software for mechanistic–empirical pavement design includes the AASHTOWare Pavement ME Design (Pavement ME) program. The Pavement ME program allows users to predict pavement distresses by applying layered elastic theory for the mechanical responses and using empirical models for the distress predictions. The layered viscoelastic pavement design for critical distresses (LVECD) program, which employs three-dimensional viscoelastic finite element analysis with moving loads, can also be used to predict the fatigue and rutting performance of pavements. The LVECD program employs the simplified viscoelastic continuum damage (S-VECD) model as the material model for the fatigue performance predictions of asphalt mixtures under complex loading and environmental conditions. This paper examines and compares the performance of 33 pavement sections from five research projects located in the United States, Canada, and South Korea by using both the Pavement ME and LVECD computer programs. To verify the results obtained from these two programs, the simulations were compared with the field performance data. In terms of ranking, the LVECD simulations provided better agreement with the field performance data than did the Pavement ME simulations. One of the main reasons for the better predictions obtained by the LVECD program is that its fatigue performance predictions depend on the mixture properties of all the layers, whereas the Pavement ME program considers the fatigue properties of only the bottom layer mixture.

Fatigue Performance Prediction of Asphalt Pavements with FlexPAVETM, the S-VECD Model, and DR Failure Criterion

“…Figure 1 presents schematic illustrations of the study mixtures and pavement structures. Basic information about these materials and field sections can be found in previous publications ( 12 , 14 ).…”

“…The damage characteristic curve represents how damage grows in the material; however, a failure criterion is needed to predict the failure of the material. For this study, the fatigue properties of the mixtures were obtained from cyclic direct tension tests following AASHTO TP 107 ( 8 , 12 , 13 ). The following sections present two failure criteria based on the S-VECD model and the dissipated pseudo strain energy concept.…”

“…The G R failure criterion has been implemented in FlexPAVE™, and the resultant software package has yielded good predictions of observed cracking in various pavements ( 9 – 11 ). Wang et al evaluated and compared the prediction accuracy of Pavement ME Design (formerly known as the MEPDG) and FlexPAVE™ using material and field data and reported that, although both programs can provide reasonable results, FlexPAVE™ yields better agreement with field measurements due to the fundamental models it applies ( 12 ).…”

Improving the Reliability of Damage Characteristic Curves in the Simplified Viscoelastic Continuum Damage Model

“…The practical significance of the thresholds was evaluated by analyzing the sensitivity of the FlexPAVEä pavement performance predictions to the variability in the damage characteristic curves. The FlexPAVEä program was recently developed under the FHWA-sponsored Hot-Mix Asphalt Performance-Related Specifications project (8). FlexPAVEä performs three-dimensional analysis of pavement structures in a computationally efficient manner to determine the stress and strain in a pavement system and to predict pavement performance using mechanics-based models.…”

Evaluation of Small Specimen Geometries for Asphalt Mixture Performance Testing and Pavement Performance Prediction

“…The effects of the specimen geometries on fatigue performance were evaluated at both the material and pavement levels. The pavement performance was predicted by using the layered viscoelastic analysis for critical distresses (LVECD) program, which was recently developed under the FHWA-sponsored Hot-Mix Asphalt Performance-Related Specifications project (14). The LVECD program computes pavement responses and performance under moving loads by using three-dimensional viscoelastic analysis and taking into account the pavement's structure and material properties.…”