摘要
为使海洋平台在服役中后期内安全服役,有必要对现役平台进行安全评估.以埕岛海域某服役中后期导管架式海洋平台为例,研究其可靠性变化问题.首先,根据平台状况资料,考虑平台结构的腐蚀、冲刷等损伤随年限增加而变化的情况,建立了反映结构实际动力特性的有限元模型;然后,考虑结构非线性,沿平台的不同方向逐级施加载荷,得到平台的桩顶位移与横向载荷的关系曲线,根据该曲线得出平台不同时间的极限承载力;最后,考虑冰荷载的不确定性,利用Monte-Carlo法研究平台每年的失效概率及可靠度指标,得到可靠度指标随服役年限变化的曲线,进而预测平台结构在未来服役期内的可靠度.
As the bearing capacity of offshore platform structures is reduced significantly with the increase of service life,safety assessment for offshore jacket platform is necessary to make the platform serve safely in the future service period.Taking the aged offshore jacket platform in Chendao as an example,its reliability assessment was investigated considering the change in resistance with time.Firstly,regarding the corrosion and scour conditions from inspection information of the aged platform,intact FE models were designed according to the platform specifications.The FE models could reflect the real dynamic characteristics.Secondly,the relationship curves between the laterally horizontal loads and the top displacements were obtained when the nonlinearity was taken into account.The ultimate bearing capacity of the platform could be evaluated according to the relationship curves.Finally,the annual failure probability and reliability index of the platform were evaluated by Monte-Carlo method when the uncertain of the ice loading was considered.The relationship curves between reliability index and service life were obtained.Furthermore,reliability of the platform during the future service period could be speculated.
出处
《江苏科技大学学报（自然科学版）》
CAS
北大核心
2010年第2期107-111,204,共6页
Journal of Jiangsu University of Science and Technology:Natural Science Edition
基金
中国博士后科学基金资助项目(20080440176)
关键词
海洋平台
可靠度
安全评估
极限承载力
offshore platform
reliability
safety assessment
ultimate bearing capacity
