海洋平台结构可靠性分析

为了延长近海平台的使用寿命，需要对现役平台结构进行可靠性分析与评价．介绍了可靠性方法及其在近海平台极限状态设计和结构评价中的应用，给出了理论公式和实际计算方法．描述了ＦＳ１导管架海洋平台结构极限状态设计和结构评价时所考虑的三种失效情形：（１）平台失效；（２）甲板支腿失效；（３）基础失效．首先提出平台的非线性结构计算模型，然后确定作用在平台、甲板和过桥上的载荷，最后分析计算系统抗力和平台的可靠性．研究结果表明，当沉没深度达１０．６５ｍ时，平台失效概率达１／１０００．根据分析结果，提出了延长平台使用寿命的技术措施。本项目研究所采用的计算方法和研究成果可供类似结构分析和工程实践参考．

Reliability Analysis of an Offshore Platform

It is necessary to analyze and evaluate the reliability of the offshore platforms on active service in order to prolong their service life.The methods of reliability analysis and evaluation are put forward,and their applications are introduced in the ultimate state design and structural evaluation of offshore platforms.The deign and evaluation processes consist of three steps:1)to put forward the calculation model for a nonlinear structure:2) todetermine the loads acting on jacket,deck and bridge;3)to calculate the system capacity and to analyze the relibility of the system.In the ultimate state design and structural evaluation of Flare support I(FSI) tripod jacket,it is thought that there are three types of its failure:1) jacket failure;2)deck log failure;3) foundation failure,The research result shows that the probability of offshore platform failure is 1/1000 when submergence depth is 1065m.