Mechanical Properties of High-Temperature Granite under Liquid Nitrogen Cooling

The cooling characteristics of liquid nitrogen can effectively weaken the mechanical properties dry hot rock reservoirs, improve porosity and permeability rock, thus development utilization geothermal resources. In order to explore weakening effect on high-temperature reservoir rocks, uniaxial compression tests, Brazil splitting three-point bending tests were conducted granite, synchronous acoustic emission monitor damage evolution rocks. It is found that under action nitrogen, elastic modulus, peak strength, fracture toughness, other granite decrease varying degrees. At different initial temperatures, degree different. higher temperature greater granite. low-temperature not only have cracking but also thermal stress If difference between two large, heat released in combination process will be higher. difference, Under show laws, ringing count increases significantly, which indicates aggravates internal making more fractured during fracturing. research results provide some scientific guidance for energy.