Finite element analysis of the performance of rigid plate soil pressure cells : Carder, D R Ground Engng, V9, N8, Nov 1976, P40–46

Abstract

The author gives an account of a study of the performance of rigid plate soil pressure cells intended for measuring the pressure at the interface between a retaining wall and the soil backfill, with particular reference to finite element analysis. The program used was that developed at TRRL by Fellows and Castledine, which is based on constant strain triangular elements and involves the calculation of external vertical nodal applied loads by waterhouse's method, and included a facility for allowing the application of radial external loads. Figures include a typical distribution of vertical stress over the face of the pressure cell, a calibration chart for cells of different stiffness used in a range of soil types and the change in cell factor with radius. It was found that a 10 per cent change in nodal stress at the edge of a plate produced a change of less than 3 per cent in the cell factor and that the cell factor was linearly dependent on the displacement of the cell plate. Comparisons were made between experimental and calculated relations between applied and 'measured' cell pressures for a washed sand and a sandy clay. Similar results were obtained and although the finite element anaysis predicts a smaller cell error than was actually obtained, it was concluded that the finite element analysis method provides a reasonable guide to the probable performance of a cell mounted flush with a rigid surface.