【摘要】 为对大跨连续刚构桥在多维随机因素作用下的安全性进行有效评估,将Monte-Carlo法与响应面法相结合,建立基于混合模拟法的结构可靠度分析方法。该方法首先利用MonteCarlo法对结构进行若干次循环分析,以此计算出各随机变量的可靠性灵敏度因子,再将灵敏度较高的输入变量继续作为随机变量,利用响应面法拟合出结构的功能函数,最后利用Monte-Carlo法求解出显式化功能函数的可靠指标。采用混合模拟法与概率网络估算法相结合计算承载能力极限状态下连续刚构桥的可靠度,以广西百色市江坝右江特大桥为例进行分析,结果表明,承载能力极限状态下,中跨跨中截面抗弯失效模式是该桥上部结构静力体系可靠度的控制失效模式。更多还原

【Abstract】 To effectively evaluate the safety of long span continuous rigid-frame bridge under the action of multivariate random variables,the Monte-Carlo method was combined with the response surface method and a structural reliability analysis method based on the hybrid simulation method was established.In the analysis method,the Monte-Carlo method was firstly used to carry out several times of repeated analysis of the structure and according to the analysis,the reliability sensitivity factors of all random variables were calculated.Then the input variables with higher sensitivity factors were continuously treated as the random variables and the response surface method was used to fit the performance functions of the structure.Finally,the Monte-Carlo method was again used to calculate the reliability indices of the explicit performance functions.By way of example of Jiangba Youjiang River Bridge in Baise City,Guangxi,the reliability of the continuous rigid-frame bridge in the ultimate bearing capacity state was calculated,using the hybrid simulation method combined with the probability network estimation method.The results of the calculation demonstrate that in the ultimate bearing capacity state,the bending failure mode of the midspan section of the central span is the controlled failure mode of the static system reliability of the superstructure of the bridge.更多还原