考虑焊接残余应力的波形钢腹板PC梁关键细节疲劳可靠度研究  

Fatigue reliability assessment of PC beam with corrugated steel webs considering welding residual stress

作　　者：刘扬 马威 张海萍 邓扬 LIU Yang;MA Wei;ZHANG Hai-ping;DENG Yang(School of Civil Engineering,Hunan University of Technology,Changsha 412007,China;School of Civil Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China)

机构地区：[1]湖南工业大学土木工程学院,株洲412007 [2]北京建筑大学土木与交通工程学院,北京100044

出　　处：《计算力学学报》2023年第1期146-152,共7页Chinese Journal of Computational Mechanics

基　　金：国家自然科学基金面上项目(52178207)资助。

摘　　要：焊接残余应力对波形钢腹板细节疲劳寿命的影响不可忽略,本文以头道河大桥为工程背景,基于ABAQUS有限元软件,建立波形钢腹板焊接构件数值模型,提出不同波折角度的波形钢腹板残余应力模型。采用瞬态分析方法,分析6种典型车辆作用下波折角区域焊缝细节的应力时程。在此基础上,构建考虑焊接残余应力和车辆荷载共同作用下的波形钢腹板细节疲劳极限状态方程,讨论不同波折角度和交通增长率对疲劳可靠度指标的影响规律。研究表明,翼缘板-波形钢腹板焊接构件斜边两侧的纵向残余应力呈对称分布,焊接细节转角区域圆弧外侧的纵向残余应力整体高于圆弧内侧,随着波折角度的增加,两侧焊缝附近的纵向残余应力变大;在桥梁设计基准期取100年时,30°波折角度焊缝细节疲劳可靠度是60°波折角度的1.05倍;交通量的线性增长对头道河大桥焊缝细节的疲劳可靠度影响较大,不考虑交通增长率的焊缝细节疲劳可靠度是α=5%的1.84倍。The influence of welding residual stress on the fatigue life of corrugated steel webs cannot be ignored.In this study,we used the Tou-dao river bridge as the research subject.An ABAQUS model of welding components of corrugated steel webs was established.Various residual stress models of corrugated steel web which considered wave angles were proposed.Then,the stress time history of the weld details in the corrugated corner area which under the action of six typical vehicles were analyzed.On this basis,the fatigue limit state equation of corrugated steel web considering the combined action of welding residual stress and vehicle load was proposed.The influences of different wave angle and traffic growth rates on fatigue reliability index were discussed.The research results show that the longitudinal residual stress on both sides of the hypotenuse of the flange plate-corrugated steel web welded member is symmetrically distributed.The longitudinal residual stress on the outside of the arc in the corner area is,on the whole,higher than that at the inside of the arc.With the increase of the twist angle,the longitudinal residual stress near the welds on both sides becomes larger.The fatigue reliability index of the weld details of the 30°fold angle is 1.05 times that of the 60°fold angle in service for 100 years.The linear increase in traffic volume has a greater impact on the fatigue reliability of the weld details of the Tou-dao river bridge,the fatigue reliability index of the weld details with a linear growth factor ofα=0%is 1.84 times that ofα=5%.

关 键 词：桥梁工程 波形钢腹板梁 断裂力学 疲劳可靠度 焊接残余应力 

分 类 号：O346.2[理学—固体力学]