Effect of compaction effort on SuperPave base course materials

Abstract

SuperPave mixes have performed well with in West Virginia, especially with respects to permanent deformation. Recent studies raise concerns with premature fatigue cracking and difficulty in compaction during construction. Two base course mixes were tested by lowering compaction effort from 100 gyrations to 80 gyrations for the 19mm mix and to 65 gyrations for the 37.5 mm mix and evaluating rutting potential with Asphalt Pavement Analyzer and Indirect Tension test. Only gyration level and binder percent were changed. Lower compaction effort resulted in an increased binder content. The 19mm mixes showed an increased rutting potential. However, investigation of the data demonstrated position of the sample in the APA machine confounded the results of the test. No statistically significant rutting potential was found with the lowered compaction effort or increased binder content for the 37.5 mm mix.