Reinforced Soil Wall Analysis and Behaviour

Abstract

The paper considers the equilibrium in reinforced soil walls. Two solutions are presented which are expected to “bound” the likely state of equilibrium in a wall. The magnitude and distribution of the reinforcement forces and the soil stresses are derived analytically, allowing the movement of the wall face to be calculated. Two non dimensional charts are given for the calculation of outward movement. The resulting magnitude of movement predicted by the two equilibrium solutions is close, so that the likely range of movement in a wall is well defined by the analysis. Incremental wall construction causes a “moving datum” for the outward movement at the wall face due to reinforcement elongation. Thus, incremental construction results in additional movement at the wall face. This is the main distinction with propped walls which do not suffer from incremental construction movement. An analysis for the incremental movement is given. The selection of compatible values of mobilised soil shearing resistance and reinforcement force in a reinforced soil wall is discussed, and new ideas put forward for the way the soil is likely to behave in the reinforced zone. The application of the concepts and the analyses introduced in the paper are fully illustrated by the prediction for the Royal Military College trial wall which is presented in a companion paper.