Bucket foundation is a new-type offshore foundation applicable especially for marginal field oil extraction

which is usually subjected to the simultaneous actions of both gravity and other environmental loads.Gravity loads act vertically while environmental loads induced by wave

wind and current are imposed laterally with both horizontal load and moment on the foundation.The responses of suction caisson foundation subjected to such a type of combined loads are therefore of great importance for the design and construction of offshore foundation.Three dimensional finite element numerical analyses are performed by using the general-purpose FEM package ABAQUS/Standard

in which the soil is assumed to obey the Mises’s yield criterion.Both the stability or failure envelopes and collapse and working mechanism of suction bucket foundation founded in the cross-anisotropic soil strata under undrained conditions subjected to monotonic loading or combined loading are discussed.