Research On Mechanical And Seepage Characteristics Of High-temperature Granite After Water Cooling Under Conventional Triaxial Stress

For high-temperature water-cooled granite samples as the research object,the RYL-600 rock shear rheometer and MTS815 multifunctional rock mechanics testing machine in different water samples after high temperature treatment mechanics test,obtain different mechanical parameters of high-temperature water-cooled granite sample,under the condition of same pore pressure difference of different high temperature transient method using MTS815 granite water-cooling sample loading different confining pressure,seepage experiment for different high temperature granite seepage properties of water sample.A series of studies show that:(1)The physical properties of granite specimens after water cooling at different temperatures were studied,and the influence of treatment temperature on the physical properties of the specimens was discussed.The porosity,T2 spectrum and pore throat distribution map of the water-cooled specimens of different high-temperature granites were measured by nuclear magnetic resonance microscopy.The analysis showed that the pore diameter of the specimens after the high-temperature treatment at 200? was small and the pore throat distribution was small.(2)Through the splitting test and uniaxial test of water-cooled granite samples at different temperatures,the tensile strength and compressive strength of high-temperature granite specimens increased first and then decreased with the increase of treatment temperature.Under different confining pressures,triaxial tests were carried out on water-cooled granite samples at different temperatures to obtain the mechanical parameters of the samples.It was found that under the same confining pressures,the peak triaxial compressive strength of the specimens first increased and then decreased with the increase of treatment temperature.At the same treatment temperature,the peak triaxial compressive strength of the specimen increases monotonously with the increase of confining pressure.(3)The transient method uses MTS815 to conduct seepage tests on different high-temperature granite water-cooled samples under the same pore pressure difference and different confining pressures.The permeability is calculated and analyzed under Darcy,and the permeability is obtained under the same pore pressure difference and confining pressure.As the treatment temperature increases,the permeability of the specimen first decreases and then increases;with the increase of confining pressure under the same pore pressure difference,the permeability of the specimen at the same treatment temperature decreases monotonously.(4)The transient method uses MTS815 to conduct seepage tests on different high-temperature granite water-cooled samples under the same pore pressure difference and different confining pressures.The non-Darcy factors,acceleration coefficients,and permeability are obtained by calculation and analysis under non-Darcy.Under the conditions of pore water pressure and confining pressure,the non-Darcy permeability of the specimens after cooling of different high-temperature granites first increases and then decreases with the increase of the treatment temperature;the permeability of the non-Darcy seepage of the specimens after the same pore pressure and the same high-temperature granite is water-cooled Decrease as the processing temperature decreases.