Reducing Earth Pressure on Retaining Walls Using EPS Geofoam

Abstract

Retaining walls are constructed to resist earth pressure and lateral thrust due to backfilling and surcharge pressures from foundations of adjacent structures. Expanded polystyrene (EPS geofoam) panels of low stiffness installed vertically against the rigid non-yielding retaining structures to reduce the lateral earth pressure due to its compressible behaviour. In the present study, numerical models are developed to validate reported physical test results for a rigid non-yielding wall. The results of the validation illustrate a good agreement between the measured results and numerical modelling. A series of numerical analysis was performed by using the verified finite-element models using PLAXIS 2D software. A parametric study has been adopted to illustrate the effectiveness of EPS geofoam density. Also, the thickness of the geofoam and the height behind the retaining structure in reducing the developed lateral earth pressure. The first group of models shows that the less density of EPS geofoam used the less Earth pressure produced on the retaining wall. The second group of models shows that the more thickness of EPS geofoam we use the less earth pressure we get. Also, backfill material relative density is one effective parameter on earth pressure as the more relative density of soil we have the less earth pressure