Temperature Sensitivity of Mechanical Properties of Cement Asphalt Mortar with Nanoparticles

Cement asphalt mortar (CAM) in high-speed lines is subjected to varying environmental conditions, which lead to the deterioration of CAM. The nanoparticles of nano-SiO₂ and nano-TiO₂ are added to improve the performance of CAM, and the temperature sensitivity of CAM with nanoparticles is primarily studied in this paper. The flexural strength and compressive strength of CAM with and without nano-SiO₂ and nano-TiO₂ were measured and compared to study the effect of nanoparticles on the performance of CAM subjected to different temperatures. Temperature sensitivity factors of flexural and compressive strength based on Arrhenius model were proposed to evaluate the temperature dependence of CAM by nanoparticles. Furthermore, the microstructure of hardened CAM was studied using scan electronic microscope (SEM) to investigate the mechanism of temperature sensitivity of CAM with and without nanoparticles. The results indicated that the flexural and compressive strength of CAM with and without nanoparticles decreased with the increasing temperature; however, the decreasing rate of strength with temperature was different in CAM with and without nanoparticles. The reduction in the decreasing rate of strength was obtained by using nano-SiO₂ rather than nano-TiO₂ in CAM. Based on the SEM results, the free asphalt was seen to be greatly reduced in the CAM with nano-SiO₂, suggesting a positive effect of nano-SiO₂ on the mitigation of temperature sensitivity of CAM.

This creative work has been published under the Creative Commons Attribution 4.0 International (CC-BY 4.0) license which allows copying, and redistribution as well as adaptation of the original work provided appropriate credit is given to the original author and the conditions of the license are met.