Evaluating the Effect of Warm-Mix Asphalt Technologies on Moisture Characteristics of Asphalt Binders and Mixtures

Abstract

The effect of warm-mix asphalt (WMA) technologies on the moisture susceptibility of a mixture and the adhesion characteristics of the asphalt binder used in it was evaluated. A 9.5-mm Superpave® mixture designed with performance-grade asphalt PG 64-22 was used as the control mixture. Four types of WMA technologies were evaluated: Advera, Evotherm, Sasobit, and SonneWarmix. The Hamburg wheel-tracking device (HWTD) was used to evaluate the effect of each WMA technology on the moisture susceptibility of the mixture at three aging times and three aging temperatures. A liquid antistrip and hydrated lime were added to any mixture that failed the HWTD to determine if they could correct the failure. Because the moisture susceptibility of a mixture is related to failure in the adhesive bond between the binder and the aggregate, a pulloff test, the bitumen bond strength (BBS) test, was used to evaluate the impact of the WMA technologies on the adhesion characteristics of the asphalt binder. The HWTD test results indicated that the moisture resistances of all mixtures improved significantly with an increase in aging time or temperature. Mixtures aged at longer times and at higher aging temperatures exhibited the best performance. The addition of the antistrip agents improved the HWTD results. The BBS test showed that only Sasobit had a significant effect on the pull-off tensile strength of the binder, although only under dry conditions. Overall, no correlation between the BBS and the HWTD was found.

Effect of Warm Mix Chemical Additives on the Binder-Aggregate Bond Strength and High-Service Temperature Performance of Asphalt Mixes Containing Electric Arc Furnace Steel Slag

“…3, along with error bars reporting the minimum and the maximum value obtained for each testing condition. First of all, it is worth noting that the experimental results in the case of limestone aggregate plate were consistent with those found by Mogawer et al (2011), confirming the reliability of test data.…”

“…Huge research indirectly investigated this issue through the assessment of moisture sensitivity of WMA since a poor adhesion at the binder-aggregate interface can lead to moisture damage. On the contrary, only few studies were addressed to the direct assessment of the bond between warm-modified binders and aggregates (Mogawer et al 2011).…”

Evaluation of Rediset for use in warm-mix asphalt: a review of the literatures

“…They evaluated the adhesion between aggregate (granite and rhyolite) and warm asphalt binders using Bitumen Bond Strength (BBS) test on dry and moisture-conditioned samples. The BBS test is a pulloff test that is carried out with the pneumatic adhesion tensile testing instrument (Mogawer et al 2011). This test was accepted as a provisional test method for AASHTO by the name of TP91 (Alavi et al 2012).…”

Warm Mix Asphalt Investigation on Public Roads - A Review

“…Less aging of binder: at high temperature the aging is more and at less temperature the aging less so WMA have less mixing and compaction temperature so it has less aging. The aging index is more it means life of pavement is more [18].…”