Investigation on Rheological Properties and Microscopic Mechanisms of Sasobit/Buton Rock Asphalt Modified Asphalt

Abstract

The objective of this study is to develop a modified asphalt with excellent rheology and workability. Buton rock asphalt (BRA) composite modified warm mix asphalt (BCMWMA) was prepared, and its rheological properties and micromechanisms were investigated. Initially, warm mix asphalt (WMA) was prepared using 3 wt% Sasobit, and then four BCMWMA samples were prepared by blending 5 wt% to 20 wt% of BRA (with 5 wt% intervals). Subsequently, the microscopic morphology and modification mechanism of BCMWMA were analysed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) tests. Finally, the rheological properties of BCMWMA were examined through conventional properties tests, rotational viscosity tests (RV), dynamic shear rheological tests (DSR) and bending beam rheometer tests (BBR). The results indicate that the BRA and Sasobit composite modifications primarily involve physical modification. BRA improves the high-temperature performance of the modified asphalt but reduces its low-temperature performance. Overall, the BCMWMA exhibits excellent high-temperature performance and workability, contributing to the green and sustainable development of asphalt pavement engineering.