Influence of anti stripping agents on performance of binders and asphalt mixtures containing Crumb Rubber and Styrene-Butadiene-Rubber

Abstract

The purpose of current research is to evaluate the influence of Anti Stripping Agents (ASAs) on performance properties and moisture susceptibility of SMA mixtures modified by Crumb Rubber (CR), Styrene-Butadiene-Rubber (SBR). In this research, to modify original binder, three different ASAs (named A, B, and C) with three percentages (0.2%, 0.4%, and 0.6% by weight of binder), Cr (7% by weight of binder) and SBR (2% by weight of binder) were used. The rheological behavior of binders was assessed through rotational viscosity, Dynamic Shear Rheometer, Multiple Stress Creep Recovery (MSCR), and linear Amplitude Sweep (LAS) tests. Also the MSCR and PG method were used to grade different binders. Performance properties of mixtures were investigated through four-point beam fatigue, resilient modulus, Indirect tensile strength (ITS), dynamic creep, moisture susceptibility and wheel track tests. Results of the MSCR test indicated that the addition of SBR/CR and ASAs causes an increase in the high-temperature behavior of the original binder at stress levels of 100 and 3200 pa. According to the LAS test results, the addition of SBR/CR and ASAs improves the intermediate temperature properties of bitumens. Mixture test results revealed that the addition of ASAs to SBR/CR modified mixtures, the resilient modulus, rutting properties, tensile strength, fracture energy, and fatigue life and moisture damage resistance of specimens improves. Among ASAs, ASA B has the highest impact on enhancing the performance of specimens. Also, 0.4% of each ASA, has the highest influence in improving the performance of specimens.