Investigation on mechanical parameters of water-rock interaction

The processes are very complex for the coupling of water-rock interaction, and the sensitivity of water for porous media material cracks should be focused for the research of fundamental mechanical properties of rocks. In the present research, the theories and measure technologies of conventional true and pseudo tri-axial tests are also analyzed. The mechanical parameters are obtained by true and pseudo tri-axial tests with/without water pressures. The idea that the tri-axial test is only suitable for the isotropic porous media materials is proposed, the sample of 50mmx50mmx100mmis proposed to conduct the tri-axial test to understand the anisotropic mechanical behaviors of porous media materials. The anisotropic Biot's coefficients and the damaged mechanical parameters under different stress states are obtained by considering the influences of unloading water pressure on porous media materials. The testing results show that variable trends of anisotropic Biot's coefficient in the different directions are not the same. A testing method of limit yield stress determination is suggested, the limit yield stress is equal to the deviatoric stress corresponding to the maximum water pressure between deviatoric stress and water pressure curve for the non-drainage test. The testing results also show the Skempton coefficient disparity is significant, and the mechanism of water pressure action is different under various injections and drainages. It is crucial for damage mechanics and civil engineering to study water-rock interaction.