Mechanical Characteristics of Coal and Rock in Mining under Thermal-Hydraulic-Mechanical Coupling and Dynamic Disaster Control

In order to reduce the risk of coal and rock dynamic disasters in the coal mine production process, the coupling mechanics characteristics of coal and rock produced in the process of coal mining in the Dingji Coal Mine are taken as the research object, and the experimental study on the deformation characteristics and the variation rule of mechanical parameters of raw coal under multifield coupling (temperature, gas, and stress coupling) was carried out. The results show that the elastic modulus, peak strain, and peak stress of raw coal samples under the thermal-hydraulic-mechanical coupling have the same change law in the test temperature range and all of them show a linear decreasing law as the temperature increases. Under the same temperature gradient increasing condition, the elastic modulus, peak strain, and peak stress show a nongradient decreasing trend as the temperature increases. Both the deformation modulus and the lateral expansion coefficient show a linear increase as the temperature increases, while the deformation modulus and the lateral expansion coefficient show a nongradient increase trend as the temperature increases under the same temperature gradient increasing condition. Under the action of the thermal-hydraulic-mechanical coupling, unloading confining pressure obviously accelerated the yield process of the coal sample, and the confining capacity of confining pressure on transverse strain of the coal sample decreased. To prevent the occurrence of coal and gas outburst, it is necessary to take specific prevention measures according to the change law of triaxial compression mechanics of a raw coal specimen under the action of the thermal-hydraulic-mechanical coupling.