The impact of acceptance criterion on HMAC moisture susceptibility
Moisture-induced damage within hot mix asphalt concrete has been a national problem. Although numerous laboratory tests have been developed over the last several decades, the premature failure of hot mix asphalt concrete is still prevalent. The failure of hot mix asphalt concrete has always been linked to the failure of test method in consistently and accurately predicting moisture sensitivity. ^ The factor most commonly disregarded is the acceptance criteria of the placed properties of hot mix asphalt concrete. To account for production and construction variability, state highway agencies typically allow a range of hot mix asphalt concrete properties to be acceptable. For instance, 7 percent of voids in total mix are specified but contractor is allowed to place hot mix asphalt concrete within 2.7 to 9.9 percent voids in total mix. An increase in voids in total mix to 9.9 percent may increase moisture sensitivity of hot mix asphalt concrete. Therefore, the objective of this study was to identify the influence of acceptance criterion in terms of voids in total mix on moisture sensitivity. Similarly, state highway agencies allow variations in binder content and gradation. Therefore, the influence of binder content and gradation at higher voids in total mix was also evaluated. ^ To achieve objectives of this study, three different aggregate types with two different binders were evaluated. The moisture sensitivity of these mixes was evaluated using two commonly used test methods: Hamburg Wheel Tracking Device and AASHTO T-283. ^ The test results from Hamburg Wheel Tracking Device and AASHTO T-283 suggest that the moisture sensitivity of hot mix asphalt concrete depends on the acceptance criteria especially voids in total mix. ^
Sagi, Surendra Varma, "The impact of acceptance criterion on HMAC moisture susceptibility" (2004). ETD Collection for University of Texas, El Paso. AAI1423725.