竖向与水平复合加载下桶形基础承载性能的分析

在竖向和水平力共同作用的复合加载条件下地基承载性能及其破坏模式是吸力式桶形基础设计与施工中的关键技术问题。为此，以大型通用有限元分析软件系统ABAQUS为基础建立了桶形基础三维有限元计算模型，运用位移控制法确定了均质软黏土地基极限承载力系数与位移之间的归一化关系；采用Swipe试验加载方法，确定了桶形基础在竖向力与水平力平面上的地基破坏包络图，从极限分析上限方法的角度探讨了由数值计算所揭示的桶形基础破坏机制。

Numerical analysis of bearing capacity behaviour of suction bucket foundations under joint loading condition of vertical and horizontal loads

Not only is the suction bucket foundation subjected to vertical loading induced by weights of offshore platform and equipments, but also undergoes horizontal force and moment caused by winds and waves. Therefore the performance of bucket foundation subject to the joint loading of both vertical force (V) and horizontal force (H) is one of the key issues in design and construction of a bucket foundation. A 3-D FEM-based computational model of bearing capacity and failure mechanism of bucket foundation under the above joint loads is proposed and then numerically implemented using the general-purpose finite element analysis package ABAQUS. The normalized relationship between the factor of ultimate bearing capacity and resulting displacement is obtained by applying the displacement controlled method for homogeneous soft soil profile. The failure envelope of the foundation in the load subspace of vertical and horizontal forces (V-H) is determined by utilizing loading procedure of the Swipe test. The load-carrying performance and failure mechanism of bucket foundation under joint loading are interpreted from the standpoint of upper-bound limit analysis based on the deformation pattern obtained from numerical analyses. The numerical results computed using the proposed method is helpful to engineering practices.