Mechanistic Evaluation of Test Data From LTPP Flexible Pavement Test Sections, Volume I: Final Report
Primary Topic: Pavement Maintenance
Description: The study reported here was conducted to assess how well some of the existing asphalt pavement mechanistic-empirical distress prediction models performed when used in conjunction with the data being collected as part of the national Long-Term Pavement Performance (LTPP) program. As part of the study, appropriate data were obtained from the National Information Management System (NIMS) for the GPS-1 and GPS-2 experiments. The first phase of the data analysis involved using the deflection test data to backcalculate pavement layer moduli values. Using representative values of the layer moduli, structural analyses were performed for up to 140 axle-load configurations for the selected test sections. Then, the Asphalt Institute and the Shell procedures were used to predict fatigue cracking and rutting damage. The computed results were compared with observed values. Based on the results, new forms of the fatigue cracking models have been proposed. Also, a new approach to predicting rutting has been developed. This new procedure would account for rutting in each pavement layer and would consider rate-hardening typically observed in the development of rutting.
This study has shown that, even given the many current limitations in the LTPP database, the LTPP data can be used successfully to develop a better insight into pavement behavior and to improve pavement performance.
This volume is the second in a series. The other volume in the series is: FHWA-RD-98-020 Volume II: Final Report-Appendices (Available from NTIS only).
FHWA Publication Number: FHWA-RD-98-012
Publication Year: 1998