Undrained HM bearing capacity of hybrid foundations in spatially variable soils

Abstract

This paper investigates the probabilistic capacity of hybrid foundations (HF) for offshore structures in spatially variable marine sediments under horizontal (H) and moment (M) combined loading. Non-stationary random fields are used to model the spatially varying undrained shear strength that linearly increases with depth. The results indicate that using hybrid foundations, with peripheral and two internal skirts of identical length (i.e. d/D = 1) is almost similar to simple skirted (SS) foundations for both deterministic and stochastic approaches. Increasing length of internal skirts to twice that of peripheral ones with d/D = 2, results however in significant increase of foundations capacity, mainly under HM combined loading.