Active P-Y Curves for Rigid Walls Supporting Granular Soil

Abstract

Abstract In the performance-based design of structures with basement floors, there is interest in quantifying the relationship between the lateral earth pressure and the wall displacement using p-y curves. This paper focuses on studying the development of active earth pressure behind rigid walls in the context of p-y curves. The study aims at characterizing the components of the p-y relationship and proposing a rigorous non-linear “at-rest to active” p-y model. To achieve this objective, walls with different heights retaining granular soils of different relative densities were modeled in PLAXIS 2D. Results indicate that active p-y curves are non-linear and are affected by the height of the wall, soil density, embedment depth, and the soil-wall interface friction angle. More importantly, results show that the p-y relationship for a frictional wall is a function of (1) the p-y relationship of an equivalent non-frictional wall and (2) the reduction in shear stress with displacement at the soil/wall interface due to friction. Results are used to derive a simplified hyperbolic p-y model for non-frictional walls and a bilinear model for the development of frictional shear stresses at the soil-wall interface. Validation experiments indicated that these simple models could provide realistic estimates of the p-y response of walls without the need for finite element analyses.