Numerical simulation of seepage failure by upward flow considering internal erosion

Abstract

In the present study, seepage failure by upward flow is numerically simulated using a seepage-deformation coupled method in which the internal erosion of fine particles and the transport of these particles are considered. The field equations are derived in the framework of multiphase mixture theory, and the erosion process is modeled as the mass transfer from the solid phase to the fluidized soil phase. In addition, the particle size distribution of soil is considered in the erosion criteria and the rate equation of the mass transfer. Using the proposed method, one dimensional upward flow in a gap-graded sandy soil is simulated. From the simulations, it is found that the seepage failure occurs under relatively low average hydraulic gradient when the internal erosion is considered. This is due to the decrease in the total stress and the non-uniformity of hydraulic conductivity due to the erosion of fine particles.