Mechanical and thermal damage properties of sandstone at high temperatures

作者：Mao Xianbiao; Zhang Lianying; Liu Ruixue; Ma Dan

来源：Electronic Journal of Geotechnical Engineering, 2014, 19 N: 3137-3150.

• Damage constitutive equation
• Effect of temperature
• High temperature
• Material testing systems
• Non-linear relationships
• Servo-hydraulic machine
• Statistical distribution
• Thermal damage

The stress-strain curves, various characteristics of peak strength and Young's modulus of sandstone were studied by using a servo hydraulic machine, MTS810 Material Testing System under different temperatures ranging from room temperature to 800 °C. The results indicate that: (1) the peak strength of sandstone trends downward with a small change in the Young's modulus when the temperature ranges from room temperature to 200 °C; (2) the peak strength of sandstone increases with a small change in the Young's modulus as the temperature rises from 200 °C to 600 °C; (3) when the temperature is over 600 °C, the peak strength and the Young's modulus decrease rapidly. We also discuss the effect of temperature on the evolution of damage properties of sandstone, based on the theory of strain strength and an assumption about the statistical distribution of the strength of the rock, by using the theory of damage mechanics while considering nonlinear relationships between micro unit failure, the Young's modulus and temperature. Moreover, the concept of thermal damage is introduced, as well as the evolution equation of thermal damage and the damage constitutive equation considering the temperature effect, given that the conditions of uniaxial compression were established, based on the relationship between the Young's modulus and temperature. The damage constitutive equation is shown to be suitable and practical in our experiments.

• 出版日期2014
• 单位中国矿业大学（北京）