桶形基础承载性能弹塑性有限元数值分析

Numerical analysis of bearing capacity behavior of bucket foundation based on elasto-plastic FEM

确定桶形基础在竖向荷载、水平荷载和力矩等共同作用下的承载特性,建立复合加载模式下桶形基础的破坏包络面,并进而依此评价海洋平台基础及地基的稳定性是桶形基础设计与施工中的关键问题.采用位移控制法和Swipe试验加载方法,分别针对单个荷载和各种荷载组合方式,在大型通用有限元分析软件ABAQUS平台上,建立了桶形基础承载性能的计算模型,确定了桶形基础在单个荷载作用下的极限承载力与复合加载作用下的破坏包络面,利用极限平衡理论探讨了桶形基础在极限状态时的破坏机理,即桶形基础地基破坏形式或失稳模式.

It is one of the key fundamental issues in design and construction of bucketfoundation-supported offshore platforms to evaluate overall stability behavior and failure mechanisms of structures and foundations under combined loading pattern comprised of both vertical and horizontal load and moment. An elasto-plastic finite element method for numerical assessment of bearing capacity of bucket foundation under combined loads is developed. Both displacement-controlling procedure and the Swipe test procedure of loading are numerically implemented by virtue of the general-purpose FEM software ABAQUS. The ultimate bearing capacity of foundation under single load component is determined while the load-carrying capacity under different combinations of various loading components mechanism is defined and failure envelopes are established in different load spaces. of foundation is examined through the distribution of plastic strain around the The failure foundation.