双随机下刚性索穹顶结构的可靠性灵敏度分析  

Reliability sensitivity analysis for rigid cable dome structure under double randomness

作　　者：岑迪钦[1,2] 高博青[1] 

机构地区：[1]浙江大学建筑工程学院,浙江杭州310058 [2]浙江大学建筑设计研究院,浙江杭州310027

出　　处：《空间结构》2011年第2期48-53,共6页Spatial Structures

基　　金：国家自然科学基金资助项目(50638050);浙江省自然科学基金资助项目(Y1110438)

摘　　要：针对目前索穹顶结构研究中没有考虑荷载的随机性和结构本身的随机性的问题,采用基于正交设计响应面的Monte Carlo法对刚性索穹顶结构进行了双随机下的可靠性灵敏度分析.以一个跨度为60m,承受轴对称均布荷载作用的肋环型刚性索穹顶结构为例进行分析,得到了结构功能函数的响应面,进而采用Monte Carlo方法得到结构的失效概率以及各随机变量对于结构失效的灵敏度矩阵.结果表明,刚性索穹顶结构的失效概率较小,且应力控制的失效概率小于位移控制的失效概率,最外圈斜索的预应力水平、荷载、刚性杆件截面积对于结构失效较为敏感.在此基础上,与相应索穹顶结构比较,两种索穹顶结构的失效主要都是位移控制,且在位移控制下,最外圈斜索的预应力水平对于刚性索穹顶结构失效的敏感程度要比整体预应力水平对于相应索穹顶结构失效的敏感程度低,刚性索穹顶结构较相应索穹顶结构更为可靠.To solve the problem that the randomness of load and structure itself was not considered in recent study of cable dome structure,Monte Carlo method based on orthogonal design response surface was adopted to make reliability sensitivity analysis under double randomness. A 60 m-span Geiger rigid cable dome under symmetric equispaced loading was studied. Approximate response surface of performance function was obtained by using response surface method, and then the failure probability and the sensitivity matrix for structural failure were obtained by Monte Carlo method. The results show that the rigid cable dome has low failure probability which is controled by displacement rather than stress. The random variables including prestress level of outermost diagonal cable, load and sectional area of rigid member are more sensitive to structural failure than others. The failure of two cable domes is mainly controled by displacement,and the sensitivity of outermost diagonal cable prestress level for rigid cable dome is lower than that of corresponding cable dome. The rigid cable dome is far more reliable under the same condition.

关 键 词：刚性索穹顶结构 双随机 可靠性 灵敏度矩阵 响应面法 

分 类 号：TU311.2[建筑科学—结构工程]