DEVELOPMENT OF FATIGUE CRACKING TEST PROTOCOL AND LIFE PREDICTION METHODOLOGY USING THE THIRD SCALE MODEL MOBILE LOADING SIMULATOR

摘要

This paper presents the use of the third scale Model Mobile Loading Simulator (MMLS3) to investigate the evolution of fatigue damage in laboratory asphalt pavement and proposes an empirical fatigue life prediction methodology. The first objective of this study was to design the asphalt slab and test protocol such that a realistic alligator cracking pattern can be obtained within a few days. After four trial pavements were constructed and tested, the proper MMLS3 test protocol was established. Critical factors that were altered in the pavement construction were base type, testing temperature, and asphalt concrete layer thickness. The structural changes of the asphalt concrete layer due to fatigue loading were periodically monitored using the surface wave technique. Decreasing stiffness, indicative of pavement deterioration, was observed. An increase in the tensile strain amplitude at the bottom of the pavement was a key measurement for evaluating the fatigue performance of the pavement. A fatigue life prediction method based on the cumulative damage analysis and the Asphalt Institute's fatigue model is proposed and verified.