SIMPLE PERFORMANCE TEST FOR PERMANENT DEFORMATION EVALUATION OF ASPHALT MIXTURES

摘要

This paper focuses on research efforts undertaken to recommend a fundamentally based laboratory Simple Performance Test (SPT) for permanent deformation evaluation of asphalt mixtures. Two triaxial permanent deformation tests are discussed: the static creep, and the repeated load (dynamic creep) tests. Both of these tests were evaluated using mixtures and performance data from three U.S. experimental sites: the Minnesota Road Project (MnRoad), the Federal Highway Administration (FHWA) Accelerated Loading Facility Study (ALF), and the FHWA Performance-Related Specifications Study (WesTrack). Two tertiary flow laboratory response parameters stood out in this research as having excellent correlation with field rut depth data. These were identified as the flow number of repetition from the repeated load test and the flow time from the static creep test. A sensitivity study was also conducted for both tertiary flow parameters, using a mixture matrix of four air void levels and four levels of binder content. The results of the sensitivity analysis indicated that both parameters are sensitive to changes in air void and binder contents tested for both the confined and unconfined state of stress.