Utilization and properties of road thermal resistance aggregates into asphalt mixture

Abstract

Abstract To improve the road performance and heat resistance of thermal resistance aggregates, thermal resistance aggregates wrapped with organosilicon resin were prepared. The optimal surface treatment process of different thermal resistance aggregates was determined. The surface wrapping effect of different thermal resistance aggregates were evaluated based on the macropore structure and microsurface morphology. In addition, the road performance of different thermal resistance aggregates before and after surface treatment were compared and analyzed. The heat resistance performance of different thermal resistance asphalt mixtures was tested by an indoor sunlight simulation test. Furthermore, the effect of surface treatment on road performance and heat resistance of a thermal resistance asphalt mixture was evaluated. The results showed that the surface treatment of shale ceramsite with organosilicon resin achieved the best result. The 24 h oil absorption decreased to 2.05%. The surface pore sealing rate was as high as 78.3%, and the opening pores could hardly be seen in the SEM images. After being surface treated with organosilicon resin, the water absorption, crushing value and abrasion value of three kinds of thermal resistance aggregates decreased by 82.87%–94.50%, 6.8%–22.07% and 10.87%–28.56%, respectively, and their adhesion increased to grade 5. The surface treatment of thermal resistance aggregates could significantly improve the high temperature performance and water stability of thermal resistance asphalt mixtures. There was little effect on the low temperature performance, while the heat resistance performance of the thermal resistance asphalt mixture was improved to varying degrees.