Modelling of suction bucket foundation in clay: From finite element analyses to macro-elements

This study aims at modelling the suction bucket foundation in clay from full finite element analyses to simplified macro-element. To ensure the reliability of finite element simulation results as much as possible, two well-known constitutive models, the Modified Cam-Clay model (MCC) and the Hardening Soil model (HS), are adopted respectively for the foundation soil which is normally consolidated clay with parameters directly determined from laboratory tests instead of inverse analysis or fitting using simple models in previous studies. The finite element analyses using both models are validated by comparing centrifugal tests and further extended to study the failure patterns in V-H-M (Vertical force-Horizontal force-Moment) space through radial displacement tests. Based on all results, two new alternative analytical formulations based on both models are then proposed to describe the three-dimensional (3D) failure envelope in V-H-M space. Finally, two new alternative macroelement design models of suction bucket foundation in clay under the same framework of hypoplasticity for both monotonic and cyclic loading conditions are proposed. By comparing with experimental results, the effectiveness and efficiency of both macro-element models are verified applicable and the one based on HS has slightly better performance than the one of MCC.