Abstract:
In the process of deep mining, the coupling effect of high stress and high water pressure leads to the evolution mechanism of rock mechanical properties more complex. The degradation effect of granite under complicated conditions for analysis and failure characteristics, this paper using NMR technology granite initial porosity measurement, by using high temperature triaxial rheological rock system to carry out the stress-seepage coupling experiment, introducing energy consumption than to realize the energy evolution of granite failure process analysis, combined with the accurate and basic characteristics of granite building stress-seepage coupling damage constitutive model. The results show that: The peak strength and peak strain of rock decrease linearly with the increase of pore pressure and the decreasing rate gradually increases, while increase linearly with the increase of confining pressure and the increasing rate gradually decreases. Rock failure strain energy shows obvious confining pressure effect and pore water pressure effect. The peak stress point is the extreme point of elastic energy. After the peak point, the elastic energy rapidly transforms into the dissipated energy of rock damage. The initial porosity of granite was introduced, the rock was regarded as solid skeleton and pore, and the stress-seepage coupling constitutive model was established based on the comprehensive consideration of deformation characteristics. Compared with the experimental results, the model was found to be of high applicability. The experimental results provide guidance for the analysis of rock deformation characteristics.