Influence of Boundary Conditions in a Finite-Element Analysis of River Levees

Abstract

The effects of boundary conditions on the stability of a river levee built on a low-permeability soil layer overlying a coarse-grained deposit were studied by using the finite-element method (FEM). The FEM analyses could predict stable or unstable levee conditions depending on the assumed distance between the levee and the external boundary of the mesh where the water table was assumed undisturbed. Possible causes of this notable drawback are discussed. The calibration of the numerical seepage model, through a back analysis of piezometer measurements, that could limit the observed boundary effects is suggested.