Moisture susceptibility of WMA mixes with modified bituminous binders

ABSTRACT

Moisture-induced damage has been a major concern associated with warm mix asphalt (WMA). This study focused on the evaluation of moisture susceptibility characteristics of WMA mixes with different WMA additives and modified bituminous binders through the tensile strength ratio (TSR) and retained Marshall stability (RMS) tests. Experimental design included two binders (polymer and crumb rubber modified), four production temperatures, and two additives (Evotherm and Sasobit), each with a different dosage. Results indicated that (i) WMA additive type and its dosage had significant effect on moisture performance of warm mixes, and (ii) Evotherm mixes exhibited higher TSR and RMS values compared to Sasobit. The results were also analyzed statistically.

KEYWORDS:

• additive dosage
• modified bitumen
• moisture susceptibility
• production temperature
• warm mixes

Acknowledgments

The authors also thank M/s MeadWestVaco India Pvt. Ltd and M/s KPL International Ltd for providing Evotherm J1 and Sasobit, respectively. The authors do not endorse any proprietary products or technologies mentioned in this paper.

Funding

The authors thank Department of Science and Technology (DST), Govt. of India for their financial support.