Probabilistic undrained bearing capacity of skirted foundations under HM combined loading in spatially variable soils

Abstract

The behaviour of skirted foundations subjected to combined vertical (V), horizontal (H) and moment (M) loading is of particular interest to the geotechnical engineers. The bearing capacity of skirted foundations under combinations of VHM loading is represented by failure envelopes, which is commonly used in its stability assessment. In current studies, failure envelopes for skirted foundations were established deterministically, ignoring the spatial variability of natural soils. The paper aimed to investigate the probabilistic failure envelope of skirted foundations in the presence of soil undrained shear strength linearly increasing with depth. Random finite element method (RFEM) combining with random field theory, finite element method and Monte Carlo simulation was conducted to evaluate the uniaxial bearing capacities and define the HM failure envelopes. The influence of spatial variability on the stochastic response of bearing capacity in the HM space was discussed.