超强台风下导管架平台结构弹塑性分析

Structure elastic-plastic analysis for jacket platform under super-typhoon

针对超强台风引起的导管架平台甲板上浪载荷,基于三线性上浪载荷时间历程,采用API模型与Stokes 5 th波理论建立了上浪载荷计算方法与流程。在此基础上,应用静力推覆分析方法考察了不同上浪高度下导管架平台结构承载能力与失效模式的变化规律,利用动力弹塑性分析方法探讨上浪高度对导管架平台结构动态特性的影响,结果表明:上浪载荷导致导管架平台极限承载能力降低,当上浪达到一定高度时,平台失效模式由桩基失效演变为导管架顶部失效;平台在弹性和塑性阶段均存在一定程度的动力放大效应,且塑性响应阶段的动力放大效应更加显著。本文研究成果可为我国深水导管架平台的安全评估与优化设计提供参考。

In view of the green water load caused by super-typhoon on jacket platform, the calculation method and procedure are established based on the trilinear time history of green water load and by u- sing the API model and Stokes 5 th wave theory. Structure ultimate bearing capacity （UBC） and failure modes （FM） were investigated for different heights of green water by Pushover method. Fur- ther, dynamic performances of the platform under different heights of green water were studied by dynamic elastic-plastic analysis. Results show that the green water load reduces the UBC of the plat- form; the main FM changes from Pile foundation failure to topside rollover collapse when the height of green water reaches a certain level;dynamic am- plification factor （DAF） was found of the platform both in elastic and plastic stages, and the dynamic effects was more pronounced in plastic stage. The studies of this paper provide valuable reference in the aspect of safety assessment and optimization design of deep water jacket platforms.