Experiments on Mechanical Properties of Siliceous Sandstone after High Temperature
摘要
To study the effect of high temperature on rock, siliceous sandstone was selected to study the physical and mechanical properties after high temperature treatment, and the high temperatures ranged from 200 ℃ to 800 ℃. In addition, samples at room temperature (25 ℃) were set as the control group. The effects of high temperature on rock were evaluated by mineral composition analysis, longitudinal wave velocity, uniaxial compressive strength change and failure morphology. It was found that high temperature had a significant effect on the rock composition, which led to changes in rock wave velocity, strength and failure mode. The strength decreased with the temperature increased, and a turning point occured at 400 ℃. The longitudinal wave velocity and peak strain at the rock failure also changed significantly at 400 ℃. To further study the influence of high temperature on the rock, the thermal damage factor DT was introduced to establish the relationship of thermal damage and the rock strength. There is a three order polynomial function relationship between DT and high temperature.