Experimental Study on the Damage and Failure Characteristics of High-Temperature Granite after Liquid-Nitrogen Cooling

To analyze the influence of liquid-nitrogen cooling on damage and failure high-temperature granite, granite samples were heated to 150~600 °C for natural treatment. Brazilian splitting tests carried out as returned room temperature, basic tensile energy evolution parameters obtained. Acoustic emission signal during loading recorded. The experimental results showed that heating process caused samples, further increased degree damage. Specifically, ultrasonic velocity liquid-nitrogen-cooled was lower than naturally cooled at each temperature. With an increase in AE ring-down counts higher samples. At same dissipated greater Liquid-nitrogen could effectively promote propagation microcracks inside result a reduction mechanical strength which be conducive efficient fracture rock fracturing.