Effect of Modifiers on the Rutting, Moisture-Induced Damage, and Workability Properties of Hot Mix Asphalt Mixtures

Abstract

The present study aims to examine the effect of modifiers (Styrene-Butadiene-Styrene and crumb rubber) on the rutting, moisture-induced damage, and workability properties of hot mix asphalt (HMA) mixtures. In this study, three types—namely, control (CB), crumb rubber-modified (CRMB), and polymer-modified (PMB)—of mixtures/binders were evaluated. The rutting properties were evaluated using a wheel tracking device and the Multiple Stress Creep Recovery (MSCR) test. The moisture-induced damage properties were evaluated using the Indirect Tensile Strength (modified Lottman) and bitumen bond strength (BBS) tests. The workability properties were evaluated using densification indices (Bahia and locking point method) and a viscosity test. The results indicate that CRMB mixtures were less workable and exhibited a better resistance to rutting than the PMB and CB mixtures. Further, the PMB mixtures had increased resistance to moisture-induced damage, while the effect of the CRMB mixtures was negligible compared to the CB mixtures.