A 3D finite element (FE) based method has been developed to model the response of large diameter monopiles in sands to cyclic wave loading. The analysis procedure tracks the generation and dissipation of pore pressures in the sand around the foundation throughout a selected design storm. Pore pressure generation is based on the cyclic shear stresses mobilised around the monopile to resist the shear and moment loading applied to the pile and the results of published laboratory cyclic test results. The design storm is represented by a wave train derived from a 6-hour storm. The dissipation of pore pressures in the sand is calculated using a fully coupled consolidation model. The FE based method has been used to investigate the effect of soil permeability and stiffness on cyclic pile performance.
Chris Humpheson, Helen Dingle and Anton Pillai
Keywords: cyclic loading, monopiles, sand
Publisher: DFI