Reliability Assessment of Strip Footings on Spatially Varying Sand

Abstract

This study aims to develop hazard curves to assess the reliability of shallow foundation design on sandy soils. The random finite element method was employed to analyze the elastoplastic behavior of soils with spatially varying deformation modulus and angle of shearing resistance, which were generated as random fields and assigned to the analysis models. The output distributions were fitted with a corresponding probability density function (PDF), and the probability of exceedance (Pf) for determined damage limits was estimated from these PDFs, forming the proposed hazard curves for the determined anisotropy ratios. The method proposed in the study was validated by a database containing field test measurements, and a sample problem was presented to exemplify the application of hazard curves. The significant contribution of this study is to form the hazard curves for superficial foundations on sandy soils by considering both the elastoplastic behavior of soil and the influence of all effecting parameters, which satisfy the serviceability limits in the foundation design codes. The curves proposed in this study provide an approach for probabilistic investigation of superficial foundations taking the variability of sands into account and robust technique for the reliability-based design of strip footings with a serviceability limit state.