Evaluation of Aging and Moisture Damage Potential of Warm Mix Asphalt Incorporating a Synthetic Wax Additive

Abstract

This paper presents the effects of a warm mix additive on the moisture damage of warm mix asphalt (WMA). Asphalt mixtures were made using different WMA contents (0, 2 and 3%) at different compaction temperatures. Aging properties were studied from the effects of artificial long-term aging on resilient modulus (MR) and indirect tensile strength (ITS) of WMAs. Moisture damage was investigated in term of tensile strength ratio (TSR) of unaged and aged specimens conditioned in one and three cycles of freezing and thawing. The results showed that the aging significant affected the MR and ITS of WMA. The additive content increased with air voids but in contrary with the bulk density. Hence, the use of higher additive content can be more beneficial in terms of resilient modulus. Decreasing compaction temperature could significantly decrease the ITS while the TSR of WMA reduced as compaction temperature decreased. From moisture damage tests, the TSR of aged samples was found to be lower than that of unaged samples