Evaluation of the characteristics of Trinidad Lake Asphalt and Styrene–Butadiene–Rubber compound modified binder

Abstract

A comprehensive experiment involving different Trinidad Lake Asphalt (TLA) and Styrene–Butadiene–Rubber (SBR) compound modified binders was conducted to investigate the rheological and aging properties of TLA and SBR compound modified binders. Four TLA (5%, 10%, 20%, and 30%) and four SBR concentrations (0%, 2%, 3%, and 4%) were selected. Dynamic shear rheometer (DSR) and bending beam rheometer (BBR) tests were performed to evaluate the rheological properties. Conventional tests (penetration, softening point, and ductility tests) were conducted on TLA and SBR compound modified binders with different aging states (i.e., original, RTFO aged, and PAV aged) to investigate the physical and durability properties. Rotational viscosity tests were performed to evaluate the workability. The results indicated that compound modified binders with TLA and SBR could improve the deformation resistance of binders by increasing the early stiffness and prolong the service life of the corresponding pavement by improving the durability, compared with base asphalt binder. The addition of TLA could degrade the low-temperature flow properties, but the degradation effect could be offset by adding SBR. The combination of 2% SBR and 20% TLA was recommended based on the comprehensive analysis of test results. The workability was degraded by introducing additives, but all binders studied met the Superpave specification.