Exit Gradient in Anisotropic Porous Medium

Abstract

The inclination of flow lines at the exit on the downstream side of a hydraulic structure has been found for a known degree of anisotropy and a given direction for the principal permeability. An analytical procedure is presented to find the exit gradient for steady confined flow in an anisotropic porous medium from known exit gradient of the corresponding fictitious isotropic flow domain. Results have been presented for distribution of exit gradient on the downstream side of a vertical sheet pile embedded in a homogeneous anisotropic porous medium of infinite depth. It is found that the zone vulnerable to piping on the downstream side of a vertical sheet pile is larger for the case of horizontal stratification than for vertical stratification.