Behaviour of Prestressed Geosynthetic Reinforced Granular Beds Overlying Weak Soil

Abstract

This paper presents an analytical model for predicting the improvement in bearing capacity of geosynthetic reinforced granular beds overlying weak soil due to prestressing the reinforcement. A punching shear failure mechanism is envisaged in the analytical model. Results obtained from a series of laboratory scale bearing capacity tests and finite element analyses are used to validate the model. The addition of prestress to the reinforcement results in significant improvement of the settlement response and the load-bearing capacity of the foundation. The parameters studied are strength of underlying weak soil, thickness of granular bed, magnitude of prestressing force, direction of prestressing forces, type of reinforcement and number of layers of reinforcement. The bearing capacity ratios (BCRs) values predicted by the analytical model are found to be in good agreement with the experimentally obtained BCR values. Finite element analysis are carried out using the FE program PLAXIS to study the effect of prestressing the reinforcement. Results obtained from finite element analysis are found to be in reasonably good agreement with the experimental results. 2013 Indian Geotechnical Society.