A discussion is presented of the influence of the hydraulic boundary conditions on the finite element stability analysis of a river levee. The problem concerns an embankment built on a low-permeability soil layer overlying a coarse-grained deposit. It is shown that the finite element calculations could predict stable or unstable conditions of the levee depending on the assumed distance between the river and the external boundary of the mesh where the water table is assumed undisturbed. The causes of this notable drawback are discussed, showing that they derive from the marked influence that the mentioned distance has on the calculated pore pressure distribution below the embankment. The calibration of a proper numerical seepage model, based on the back analysis of piezometer measurements, is suggested as a possible way to limit the observed boundary effects.
ON THE FINITE ELEMENT STABILITY ANALYSIS OF SLOPESUNDER INCREASING PORE WATER PRESSURE
CIVIDINI, ANNAMARIA;GIODA, GIANCARLO;
2011-01-01
Abstract
A discussion is presented of the influence of the hydraulic boundary conditions on the finite element stability analysis of a river levee. The problem concerns an embankment built on a low-permeability soil layer overlying a coarse-grained deposit. It is shown that the finite element calculations could predict stable or unstable conditions of the levee depending on the assumed distance between the river and the external boundary of the mesh where the water table is assumed undisturbed. The causes of this notable drawback are discussed, showing that they derive from the marked influence that the mentioned distance has on the calculated pore pressure distribution below the embankment. The calibration of a proper numerical seepage model, based on the back analysis of piezometer measurements, is suggested as a possible way to limit the observed boundary effects.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
