多失效模式下的地铁深基坑系统可靠度分析  

Analysis on the Reliability of Metro Deep Foundation Pit System under Multiple Failure Modes

作　　者：吴贤国[1] 王雷[1] 冯宗宝 覃亚伟[1,2] 秦文威 WU Xianguo;WANG Lei;FENG Zongbao;QIN Yawei;QIN Wenwei(School of Civil and Hydraulic Engineering,Huazhong University of Science and Technology,Wuhan 430074;Wuhan Huazhong University of Science and Technology Test Technology Co.,Ltd,Wuhan 430074)

机构地区：[1]华中科技大学土木与水利工程学院,武汉430074 [2]武汉华中科大检测科技有限公司,武汉430074

出　　处：《现代隧道技术》2022年第4期167-175,共9页Modern Tunnelling Technology

基　　金：国家自然科学基金(51778262,71571078,51308240)。

摘　　要：为分析土体抗剪强度参数不同相关系数情况下深基坑可靠度指标的变化规律,以Copula理论为基础,结合单失效模式的建模过程,分别对深基坑的抗滑移稳定、抗倾覆稳定以及抗隆起稳定建立了失效功能函数,并以串联的方式,实现了基于Copula理论的深基坑系统失效可靠度分析。结果表明:抗滑移稳定和抗隆起稳定占系统稳定的主要部分,而抗倾覆稳定相对占比较轻;抗剪强度参数相关性的变化会显著改变各失效模式下系统的可靠度指标,证明在可靠度设计中参数相关性的影响不能忽略;不同Copula函数对可靠度计算的影响较大,对参数的分布情况进行拟合选优是必要的,直接假定参数服从高斯分布可能会低估工程的失效概率。In order to analyze the variation pattern of reliability indicators of deep foundation pit under different correlation coefficients of soil shear strength parameters, the failure functions were established for anti-sliding stability,anti-overturning stability and anti-uplift stability of deep foundation pit, respectively, based on Copula theory and in combination with the modeling process of single failure mode. Then, the failure reliability of deep foundation pit system based on Copula theory was analyzed in series. The application results show that: anti-sliding stability and anti-uplift stability account for a major part of the system stability, while anti-overturning stability only accounts for a small part;Reliability indicators of the system under each failure mode may change significantly as function of the correlation of shear strength parameter, which proves that the influence of parameter correlation cannot be ignored in reliability design;Different copula functions have a great impact on reliability calculation. So, it is necessary to fit and optimize the distribution of parameters. The failure probability of the project may be underestimated if it is directly assumed that the parameters follow Gaussian distribution.

关 键 词：深基坑稳定 抗剪强度参数 COPULA理论 系统可靠性 蒙特卡洛模拟 

分 类 号：TV551.4[水利工程—水利水电工程] U451[建筑科学—桥梁与隧道工程]