Unsteady Seepage Through Random Fracture Network in Rock Mass

Abstract

It is of great importance to study the unsteady fluid flow in the fracture network in rock mass and to simulate the seepage field in the fractured rock mass. The random distribution of the fracture network in rock mass is simulated by the Monte-Carlo method. The numerical program is developed based on the mathematical model of unsteady seepage in the fracture network. A case study is carried out by means of the program. It can be concluded that (1) the hysteresis of the hydraulic head distribution in the unsteady seepage field occurs in the case when the boundary condition is varying; (2) the hysteresis of the hydraulic head distribution in the unsteady seepage field is more obvious on the condition of the randomly variable apertures than the uniform apertures; (3) the seepage discharge is centralized in the larger-aperture channel; and (4) the hydraulic head distribution in the unsteady seepage field can be effected greatly by the variable apertures when the boundary hydraulic head conditions of the upstream and the downstream are varying greatly.