Displacement-Dependent Earth Pressures on Rigid Retaining Walls with Compressible Geofoam Inclusions: Physical Modeling and Analytical Solutions

Abstract

AbstractA rigid nonyielding retaining structure needs to be dimensioned to have adequate stiffness, such that it can resist mobilized lateral earth pressures. This corresponds to the at-rest condition, as there are, in general, negligible lateral deformations in the backfill. Measures that can mobilize higher soil shear strength and reduce lateral thrust are therefore sought to provide a more efficient design. The present study investigates the possibility of inserting compressible geofoam panels against rigid walls using physical model testing. Controlled yielding is allowed in the backfill with the occurrence of deformations in the geofoam. The mobilized earth pressures vary from the maximum at rest, to the intermediate, and finally to the minimum full active state depending on the magnitude of displacement. The effects of geofoam thickness and stiffness on lateral earth pressure reduction are explored. The measured pressure and displacement distributions form a comprehensive reference for use in calibr...