The phenomenon of the movement of f

The phenomenon of the movement of fine particles or the change of particle composition under the action of long-term seepage water is called osmotic deformation or osmotic failure. The main failure modes include flow soil, pipe surge, contact scour, and contact surface along the roof and floor of the fault, etc. When the material in the fault fracture zone causes seepage damage, a concentrated seepage zone will be formed, which will bring adverse effects on the stability of the dam. Therefore, it is necessary to carry out field or indoor permeability stability test in engineering geological survey, to calculate the safety factor of critical gradient and failure gradient, and to get the permissible gradient to evaluate permeability stability.