Experimental study of influence of seepage pressure on joint stress-seepage coupling characteristics

In order to study the influences of seepage pressure on joint stress-seepage coupling characteristics,changing trends of rock stress,displacement,joint hydraulic aperture and conductivity along with shear displacement are analyzed according to compression-shear seepage tests of six groups man-made joint specimens under constant normal load(CNL) and constant normal stiffness(CNS);and the influencing law of seepage pressure on stress-seepage coupling characteristics of joint rock is obtained.The results indicate that shear stress,displacement,hydraulic aperture and conductivity of joint specimen are related to seepage pressure obviously.The shear stress decreases along with the increase of seepage pressure.Normal deformation,hydraulic aperture and conductivity increase as the seepage pressure increases.During the compression shear seepage test,shear dilatancy effect appears in joint specimens under different seepage pressures.The research could provide scientific theory basis for surrounding rock stability when encountering water and control technology of seepage hazard of deep rock engineering.