Evaluation of moisture susceptibility tests for warm mix asphalts

Moisture sensitivity has been identified as an area of concern for warm mix asphalt (WMA) mixtures. To evaluate WMA's influence on moisture damage, three field-produced mixes were selected for evaluation. All WMA mixes studied used the same chemical WMA additive. The objectives are to compare hot-mix and WMA performance in moisture susceptibility tests, compare indirect tensile strength and Hamburg performance of pavement-cores and laboratory compacted samples, investigate reheating effect of WMA compared to hot-mix asphalt for quality-control purposes, and understand the sensitivity of WMA's stripping inflection point to oven-aging time and temperatures. Tests indicate pavement-cores performed better than gyratory samples in the Hamburg. Trends indicate Hamburg results are dependent upon temperature and higher temperatures correlate with better performance.