全局临界强度分枝-约界法的有效强度改进  

Effective strength improvement of global critical strength branch and bound method

作　　者：高凯 刘纲[1,2] GAO Kai;LIU Gang(College of Civil Engineerings Chongqing University,Chongqing 400045,China;The Key Laboratory of New Technology for Construction of China in Mountain Area of the Ministry of Education,Chongqing University,Chongqing 400045,China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045

出　　处：《吉林大学学报（工学版）》2021年第2期597-603,共7页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家自然科学基金项目(51578095);重庆市研究生科研创新项目(CYB20027)。

摘　　要：目前常用的全局临界强度分枝-约界法在计算有效强度时未考虑构件恒载的内力重分配,当恒载在结构体系总荷载中占比较大时,得到的失效模式可能与结构实际破坏路径不符。针对这一问题,将结构失效单元的恒载视为外荷载施加于相邻结构单元,在考虑构件恒载重分布的基础上,通过简化两端固支梁模型推导剩余结构单元内力和有效强度的计算方法,提出更全面反映结构系统失效模式识别的改进方法,并利用某连续刚构桥对所提方法进行验证。结果表明:改进方法得到的主要失效模式、失效路径与桥梁实际破坏情况相符,且不会遗漏桥梁结构体系的失效模式。In view of the existing failure mode search method,the global critical strength branch and bound method,the failure element is directly deleted in the effective strength calculation without considering the dead load and internal force redistribution. The failure mode searched by this method is not consistent with the actual failure path of the structure. Therefore,a more comprehensive method to reflect the failure mode of bridge is proposed. The dead load effect of the structural failure element was applied to the adjacent structures as part of the external load. Considering the redistribution of the internal force of the structure,the internal force and effective strength of the remaining structural system element was optimized. The improved branch and bound method was established. A continuous rigid frame bridge was used to verify the improved method. The results show that the main failure mode of the continuous rigid frame bridge is obtained by the improved method,and the failure path is consistent with the actual damage situation of the bridge,and the failure mode of the bridge structure system is not missed.

关 键 词：桥梁工程 失效模式 改进分枝-约界法 恒载效应 内力重分布 

分 类 号：U447[建筑科学—桥梁与隧道工程] TU997[交通运输工程—道路与铁道工程]