Experimental Study of the Stress Dependence of the Permeability of Rock

The seepage evolution characteristic of rock materials is very significant for the stability and safety of rock engineering. In this research, triaxial compression and water seepage tests were carried out on sandstone specimens. Based on the experimental results, the relationship between permeability and deformation is analyzed in detail. The results show that the permeability decreases with the increase of deviatoric stress at the initial compaction and elastic deformation stages, while the permeability increases with the increase of deviatoric stress at the stages of yield deformation, stress sharp drop and residual stress. The permeability evolution in rock is inherently coupled with the deformation, damage and failure process. It is highly related to the initiation and propagation of cracks. The compressive strength is found to decrease when the pore water pressure is higher and to increase when the confining pressure is higher.