大跨度钢管混凝土劲性骨架拱桥地震易损性分析  

Seismic vulnerability analysis of long-span CFST stiff-skeleton concrete arch bridges

作　　者：王志远[1] 赵人达[1] 吴鑫睿 赵成功 WANG Zhiyuan;ZHAO Renda;WU Xinrui;ZHAO Chenggong(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,成都610031

出　　处：《振动与冲击》2023年第16期72-81,共10页Journal of Vibration and Shock

基　　金：四川省科技计划(2020YFH066)。

摘　　要：为了探究完善钢管混凝土劲性骨架拱桥的地震损伤评估方法,以一座上承式高速铁路劲性骨架拱桥为工程实例,开展同种桥型的地震易损性研究。首先,基于OpenSEES平台建立拱桥的非线性数值模型;然后,通过非线性动力时程分析及增量动力分析对主拱肋子构件、交界墩及拱上立柱的地震损伤进行评估;最后,引入两种Copula函数建立串联体系下主拱肋构件系统的易损性曲线,并将其与子构件及基于第一可靠度原理的系统易损性进行对比。结果表明:在三向地震动作用下,主拱肋外包混凝土的损伤概率与损伤程度均明显大于钢管混凝土,且后者的易损位置将随着地面峰值加速度的增大而发生从跨中向拱脚的改变;主拱肋系统的易损性更偏向于外包混凝土,L/4拱肋截面的损伤概率最大;交界墩与拱上立柱的保护层混凝土的易损性水平显著高于纵向钢筋和核心混凝土,位于L/4拱肋位置的立柱损伤概率最大。抗震设计时应重点考虑对易损部位采取加强的设防措施。To further explore and improve the seismic damage assessment method for concrete-filled steel tube stiff skeleton concrete arch bridges,a deck type high-speed railway stiff-skeleton concrete arch bridge was taken as the engineering example to carry out a study on the seismic vulnerability of the same bridge type.Firstly,a non-linear numerical model of the arch bridge was established based on the OpenSEES platform.Then the seismic damage of the main arch rib sub-members,junction piers,and arch columns was assessed by non-linear dynamic time analysis and incremental dynamic analysis.Finally,two Copula functions were introduced to establish the susceptibility curves of the main arch rib system in the tandem system and compare them with the sub-members and the system susceptibility based on the first reliability principle.The vulnerability of the system was compared with that of the subcomponents and the system based on the first reliability principle.Results show that the damage probability and the damage level of the main arch rib outsourced concrete are significantly higher than that of the concrete filled steel tube under the action of three-way ground vibration,and the vulnerable position of the latter will change from the middle of the span to the arch springing as the peak ground acceleration increases.The vulnerability of the concrete in the protective layer of the junction pier and the column on the arch is significantly higher than that of the longitudinal reinforcement and core concrete,and the column at the L/4 arch rib location has the highest probability of damage.The columns located at the L/4 arch ribs have the highest probability of damage.The seismic design should focus on the strengthening of vulnerable areas.

关 键 词：钢管混凝土劲性骨架拱桥 地震易损性 主拱肋构件系统 Copula函数 相关性 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U448.216[交通运输工程—道路与铁道工程]