Strain compatibility analysis for geosynthetics reinforced soil walls

The methods currently used for the design of reinforced earth walls with extensive geosynthetic reinforcements can be broadly classified as: (1) Working stress design methods that basically rely upon restrictive assumptions with regard to the state of stress in the soil; and (2) limit equilibrium methods that essentially use conventional slope stability analyses, modified to account for the reinforcement effect of the global stability of the reinforced soil mass. Neither of these approaches considers the fundamental requirements of strain compatibility between the reinforcement and the soil nor can they provide any evaluation of the effect of soil dilatancy and extensibility of the reinforcement on the mobilized tension forces and structure stability. This paper presents a strain compatibility design approach that is fundamentally based on the analogy between the plane strain shear mechanism that develops along a potential failure surface in the actual structure and the response of the reinforced soil material to simple shearing. The soil-reinforcement load transfer model used in this analysis allows for the evaluation of the effect of soil dilatancy and extensibility of the reinforcement on the generated tension forces and on the probable location of the potential failure surface.