Ultimate dynamic bearing capacity of shallow strip foundations - Reliability analysis using the response surface methodology

Abstract

A reliability analysis of the pseudo-static dynamic bearing capacity of a strip footing using the finite difference (FDM) numerical is presented in this paper. The two components (structure-inertia and soil-inertia) are either considered in this work. The results of the numerical study are presented and compared with available analytical solutions proposed in the literature. The reliability index is calculated using the First-Order Reliability Method (FORM). The Hasofer-Lind reliability index is evaluated using the Response Surface Methodology (RSM) which is optimized using a Genetic Algorithm (GA) to reduce the time computation. The horizontal seismic coefficients (kh) and the soil shear strength parameters are considered as random variables. The latter are considered using normal and non-normal distributions. A comparative study using a correlation between the soil shear strength parameters allows showing that a negative correlation is conservative. The reliability index of the seismic bearing capacity is influenced by the distributions of the random variables.