Experimental and analytical study on heating and road performance of asphalt mixture with silicon carbide and ferroferric oxide composite structure layer

Abstract

Microwave heating is currently considered to be the most promising clean energy technology for asphalt pavement deicing. In order to improve the heating efficiency of pavement surface, a 10 mm silicon carbide (SiC) and ferroferric oxide (Fe3O4) composite structure layer (CSL) was designed on the pavement surface. The surface heating efficiency and road performance of asphalt mixture with CSL were investigated by laboratory experiments, and the distribution of electromagnetic and temperature fields were analyzed by numerical simulations. The experimental results show that the surface temperature of asphalt mixture with CSL was 1.64 and 1.36 times higher than that of the ordinary asphalt mixture and the asphalt mixture with SiC and Fe3O4 composite material, and it remained stable before and after repeated heating and water bath, with a difference of only 1 ℃∼1.7 ℃. The asphalt mixture with CSL had good road performance. The Marshall stability, residual stability and interlayer shear strength could remain above 10 kN, 92% and 4 MPa after repeated heating. The numerical simulation results show that the asphalt mixture mixed with microwave absorbing materials produced a larger electromagnetic field intensity. The heat of asphalt mixture with CSL was mainly concentrated on the road surface because the absorbing material was concentrated on the road surface. In contrast, because there was no difference in microwave absorption capacity throughout the asphalt mixture with SiC and Fe3O4 composite material, the heat distribution was mainly influenced by the electromagnetic field intensity. In general, asphalt mixture with CSL has higher surface heating efficiency and road performance.