Preparation and Properties of High-Viscosity Modified Asphalt with a Novel Thermoplastic Rubber

Abstract

With the increasing demand for improved road performance and sustainable development, modified asphalt is increasingly being used in pavement construction. This study investigates the preparation and properties of a novel high-viscosity modified asphalt. Firstly, different contents of novel thermoplastic rubber (NTPR) were mixed with neat asphalt to prepare high-viscosity modified asphalt (HVA). Then, the basic physical properties containing penetration, a softening point, ductility, and viscosity were conducted. Moreover, the rheological properties of the HVA before and after aging were analyzed via a dynamic shear rheometer test and a bending beam rheometer test. Finally, the dispersity of the modifier in HVA was analyzed via fluorescence microscopy. The results show that adding the NTPR restricts the flow of asphalt to a certain extent and improves the high temperature performance of asphalt. Furthermore, the apparent viscosity of HVA with various contents increases less and is always less than 3 Pa·s. Although adding NTPR makes the asphalt brittle, the HVA can meet the requirements when the NTPR is from 6% to 11%. With the increase in the NTPR, the modifier forms a mesh structure in the asphalt, enhancing its stability. Considering the above results, HVA with 10~11% of NTPR is recommended because it has better comprehensive properties.