Determination of displacement-related passive earth pressure.

Abstract

The mobilisation of earth pressure depends on the magnitude of displacement. Large displacements are required for the full mobilisation of the passive earth pressure compared to that required for full mobilisation of the active earth pressure. In this paper, a semi-empirical approach for the determination of displacement-related passive earth pressure is presented. The approach is based on the establishment of mobilised friction angle for any wall movement. The experimental observations made by earlier researchers are analysed for three modes of rigid body movements, namely, translation, rotation about the top (RT) and rotation about the bottom (RB). Using tables from Kerisel and Absi to estimate the mobilized friction angles, equations are developed for the conservative estimate of passive earth pressure for all modes of wall movements, which can be used to get displacement related passive earth pressure. An illustrate example shows the use of the proposed equations for obtaining the displacement-related passive earth pressure distribution for all the three kinds of rigid wall movements. The suggested semi-empirical approach is applied to a retaining wall problem demonstrating its rationality and cost effectiveness.