Evaluation of a Full Scale Wheel Load Tester to Determine the Rutting and Moisture Susceptibility of Asphalt Mix in Laboratory

Although several laboratory rutting tests are currently in use in different states, very few of the tests use full scale loading conditions. Therefore, current test methods are good to evaluate the effects of different mix parameters, but often do not correlate well with field rutting distresses. The objective of this study is to evaluate a full scale laboratory wheel load tester by comparing the rut depths obtained in asphalt pavement analyzer (APA) test. A full scale wheel load testing will eliminate the need of rigorous field evaluation. Laboratory made hot mix asphalt (HMA) and warm mix asphalt (WMA) have been used in dry and submerged condition for evaluation of this tester. After 1200 wheel passes the rut depth for HMA and WMA was found to be 2.8 and 3.8 mm, respectively, for dry conditions, and 3.3 and 5.8 mm, respectively, for submerged conditions. Binder was extracted and recovered from WMA and HMA specimens, and it was hypothesized that increased rutting and moisture susceptibility of WMA specimen is the result of reduced short term aging of the WMA than that of HMA.