Evaluating laboratory-induced asphalt concrete moisture damage using surface waves

The feasibility of multichannel analysis of surface wave testing was considered against dynamic modulus, indirect tensile strength and visual rating as a potential indicator of asphalt concrete moisture damage. Three replicates of field-produced asphalt concrete plate specimens were each tested at four levels of air-void content and moisture conditioning using a similar method as used in AASHTO T283-02. The effect of the various conditioning levels was examined on each of the different test results. The indirect tensile strength correlated best with the number of conditioning cycles, followed by surface wave testing, while dynamic modulus was found to be least sensitive. Minimum retained parameter thresholds were developed for each method, according to a visual stripping rating of the broken tensile specimens. Given the reasonable performance, compared to the reference test results, multichannel surface wave testing was considered feasible for evaluating moisture damage effects in the laboratory-conditioned specimens.