倒T型导管墙桩基防波堤循环承载力有限元分析

Finite element analysis of cyclic bearing capacity of the inverse T-type breakwater with jackets and pile foundations

为考虑软土地基循环软化效应，通过二次开发将软土的循环强度嵌入大型通用有限元软件ABAQUS平台中，基于拟静力分析建立倒T型导管墙桩基防波堤结构稳定性计算模型。通过有限元法分析了结构在波浪荷载作用下的循环承载力，并探讨了土体循环软化效应对结构破坏模式产生的影响以及结构尺寸参数对循环承载力的影响.研究结果表明：考虑土体循环软化效应时倒T型导管墙桩基防波堤结构的循环承载力较不考虑土体循环软化效应时极限承载力明显降低，降低程度在28．72％～41．20％之间；考虑土体循环软化效应后，该结构破坏模式有可能发生改变，其破坏模式可能由桩身屈服引起结构失稳转化为土体强度不足导致结构破坏。

Considering cyclic-softening effect of soft soil foundation, cyclic strength of soft soil was embedded in the framework of the general finite element software ABAQUS by secondary development. Then, taking into account the pseudo-static analysis, it has been formulated a calculation model about the structural stability of the inverse T-type breakwater with jackets and pile foundations. Cyclic bearing capacities of the structures under action of wave load have been analyzed with the finite element method, and the influence of cyclic-softening effect of soft soil foundation on structural failure mode as well as the influence of structure size parameters on cyclic bearing capacity has been discussed. The results show that the cyclic bearing capacity of the inverse T-type breakwater with jackets and pile foundations is clearly lower than the ultimate bearing capacity without considering cyclic-softening effect of soft soil, and the rate of reduction is between 28. 72% and 41. 20% for the structure model. In consideration of the cyclic softening effect of soft soil, the failure mode of the structure may change from structure displacement for piles body yielding to structural failure caused by soil strength insufficient.