Abstract: In the study of the sand permeability characteristics, most of them are based on normal pressure conditions, while the penetration characteristics of the sand under the high pressure is less. In the water conservancy engineering, the sand in deep mines is often under high pressure conditions, in order to study the permeability of the deep quartz sand, this paper uses the high pressure triaxial shear test equipment to perform permeability tests under the high confining pressures and high osmotic pressures. The permeability characteristics with different confining pressures under the same osmotic pressure and with different osmotic pressures under the same confining pressures are tested. The results show that under the same osmotic pressure, the coefficient permeability decreases with the increase of the confining pressure and the reduction rate is smaller and smaller. Under the same confining pressure, the coefficient of permeability is reduced, and the magnitude reduction is less and less. Further, this paper also analyzes the grain size variation before and after the tests. It is observed that the particle breakage is occurred during the test, and the fine particles of the particle size of <0.1 mm in the sample are increased, so that the coefficient permeability of the quartz sand is reduced. 

Key words: Coefficient of Permeability, High Confining Pressure, Quartz Sand, High Osmotic Pressure