【摘要】 以储液容积为16万m~3的大型LNG储罐为工程背景,采用ANSYS有限元分析软件建立分析模型,通过其可靠度分析模块(PDS)中的响应面法对储罐的单元失效概率进行分析,提出了失效单元相应的可靠指标;通过等效线性求交法逐步找出储罐的失效路径,提出了一种搜寻结构体系失效路径的新方法,根据结构体系的界限估计法求得储罐在地震作用下的体系可靠指标范围。同时指出,储罐体系的破坏是由罐壁顶部的强度破坏与罐壁底部的强度破坏两种主要失效模式所组成的串联系统的破坏。本文的研究可为完善大型LNG储罐可靠度分析理论和国产化设计提供参考。更多还原

【Abstract】 Based on an actual large LNG storage tank with a volume of 160,000m~3,the model was set by ANSYS software,the unit failure rate was analyzed through using response surface method in PDS,and the reliability index of failure unit was proposed.A failure path could be found by equivalent linearization method,and a new method of searching for structure failure paths was proposed.The scope of system reliability index was obtained according to the boundary estimation method of the structural system.Besides,it is pointed out that the strength destruction of tank walls including both the top and bottom tank walls was considered as the most primary modality.The paper would provide useful information for further improving reliability theory and domestic deign for large-scale LNG storage tanks.更多还原