Properties of failure mode and thermal damage for limestone at high temperature

The mechanical properties of limestone such as the stress-strain curve, the variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the action of temperatures ranging from room temperature to 800 °C. Our results show that: 1) the temperature has not clear effect on the mechanical properties of limestone from room temperature to 600 °C. However, the mechanical properties of limestone deteriorate rapidly when the temperature is above 600 °C. In this case, the peak stress and modulus of elasticity decrease rapidly. When the temperature reaches 800 °C, the entire process, showing the stress-strain curve is displayed indicating an obvious state of plastic-deformation; 2) the failure mode of limestone shows the breakdown of tensile strength from room temperature to 600 °C, as well as the compress shearing damage over 600 °C; 3) combining our test results with the concept of thermal damage, a thermal damage equation was derived.