An Experimental Study On Seepage Flow Of Single Fracture

Fractured rock mass exist in the rock engineering, hydraulic engineering, petroleum engineering and many other areas, research at home and abroad to one-way flow test, Most of the natural joints are in the state of compressive stress, and the stress acting on the joint can be decomposed into the normal stress of the vertical joint and the shear stress of the parallel joint, This paper adopts radial flow research model, through the test to study the factors of Normal pressure , Infiltration water pressure and crack roughness, to analysis the different factors in the test process of the principle of the role.This paper based on the existing fracture flow theory , Combined with test data, the work and conclusions are as follows:(1) When loading the normal pressure, the fissure surface in the different normal pressure, the erosion of the traces of water is generally close.The area of the scouring is concentrated at the inlet of the specimen center, and the water flow near the inlet produces a large turbulence. The seepage flow is similar to the infiltration water pressure in a linear relationship with different normal pressure, It is shown that the motion characteristics of fissure water are in line with Darcy's law during the experiment. When the infiltration pressure is the same, the seepage flow is the same,The contact state of the structural plane does not change with the increase of the normal pressure,but maintains a stable fissure opening.(2) Under the shear load, the maximum shear force of the smooth specimen is the friction force, and the value is very small, the structural plane after shearing is complete and does not change. And the seepage flow increases at the beginning of the shear displacement,the movement of the structural plane contributes to the discharge of the water flow and increases the permeability coefficient. Rough fractures (including complete occlusion and incomplete occlusion), the maximum shear force depencds on the structural fracture area and it is related to the material parameters, under the action of different normal forces, when the complete occlusion of the specimen damage area is basically the same, so the maximLum shear force difference.(3) Completely bite the rough specimen, the shear force in the rapid increase to the process of destruction, the normal displacement also has an increasing process, while seepage flow are reduced, indicating that the initial stage of cutting is in the state of shear. In the event of shear damage, the normal displacement will be reduced, the fracture of the structural plane makes the fissure width larger.