Experimental Study on Three Dimensional Coupled Stress-Seepage Law of Single Fracture

Abstract

Equation of three dimensional stress, seepage pressure and permeability coefficient was obtained by theoretical analysis. Applying the true triaxial rock testing system of coupled stress-seepage, seepage test of granite sample with prefabricated single fracture was made under three dimensional coupled stress-seepage. The results show that three dimensional stress have the inhibition effect on single fracture seepage, and the normal main stress, having the leading role, obviously influences the permeability coefficient; seepage pressure has the promote effect on single fracture seepage, resisting the normal main stress. Fitting formula of granite permeability coefficient was gained under coupled stress-seepage which indicated the exponential relationship between permeability coefficient and three dimensional stress and seepage pressure.