全装配式钢桁-混凝土组合梁剪力件焊缝疲劳分析  

Analysis of Weld Fatigue Performance of Fully-Assembled Steel Truss-Concrete Composite Beam PCSS Shear Connector

作　　者：简传熠 陈浩 周志祥[1,3] 朱虎勇 高燕梅[1] JIAN Chuanyi;CHEN Hao;ZHOU Zhixiang;ZHU Huyong;GAO Yanmei(School of Civil Engineering,Chongqing Jiaotong Univ.,Chongqing 400074,China;China Jiaotong Shanghai Waterway Survey&Design Institute Co.,Ltd.,Shanghai 200120,China;State Key Laboratoryof Mountain Bridge&Tunnel Engineering,Chongqing Jiaotong Univ.,Chongqing 400074,China;Zhejiang Transportation Planning&Design Institute,Hangzhou 310012,China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]中交上海航道勘察设计研究院有限公司,上海200120 [3]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074 [4]浙江省交通规划设计研究院,杭州310012

出　　处：《三峡大学学报（自然科学版）》2021年第2期53-60,共8页Journal of China Three Gorges University：Natural Sciences

基　　金：国家自然科学基金项目(51778094);重庆交通大学研究生教育创新基金项目(2019S0141);云南省交通运输厅科技项目(云交科(2018)28号)。

摘　　要：为了研究全装配式钢桁-混凝土组合梁桥剪力连接件焊缝疲劳问题,基于全装配式钢桁-混凝土组合梁传力机制,提出了全装配式钢桁-混凝土组合梁非连续传力模型理论,利用该理论计算得到了组合梁界面滑移值和剪力值,并进一步得出组合梁在荷载上限的焊缝剪应力幅值,以此来评价焊缝的疲劳性能.通过设计一实桥缩尺负弯矩区段模型进行疲劳试验,观察全装配式钢桁-混凝土组合试验梁剪力件焊缝在全熔透无损伤情况下的疲劳情况并和非传力模型计算结果进行对比分析.结果表明:随着疲劳加载次数的增加,试验模型桥面板和钢桁的应变值变化在7%以内,未发生应变突变,表明结构整体性良好,未发生焊缝疲劳失效;通过非传力模型计算出组合梁最大剪应力幅值为32.90 MPa,小于组合梁剪力连接件的容许抗力值69.56 MPa,焊缝剪应力幅值远远低于抗力值,不会产生焊缝疲劳问题,这与试验所得结果一致,为之后研究全装配式钢桁-混凝土组合梁的疲劳问题提供了参考.In order to study the weld fatigue problem of fully assembled steel truss-concrete composite girder bridges,based on the full-assembly steel truss-concrete composite beam force transmission mechanism,the theory of non-continuous force transmission model of fully assembled steel truss-concrete composite beams is proposed.Using this theory,the interface slip value and shear force value of the composite beam were calculated,and the weld shear stress amplitude of the composite beam at the upper limit of the load was further obtained to evaluate the fatigue performance of the weld.Fatigue test was carried out by designing a model of negative bridge bending moment section of a real bridge,the fatigue condition and non-transmission model of the fully welded steel truss-concrete composite test beam shear joint under full penetration and no damage were observed.The calculation results were compared and analyzed.The results show that with the increase of the number of fatigue loadings,the strain values of the bridge deck and steel slab of the test model change within 7%,no strain mutation occurs,indicating that the structural integrity is good,no weld fatigue failure occurs.Through the non-transmission model,the maximum shear stress amplitude of the composite beam is calculated to be 32.90 MPa,which is less than the allowable resistance value of the composite beam shear joint of 69.56 MPa.The weld shear stress amplitude is much lower than the resistance value,and no weld fatigue problem occurs.The results obtained by the test are consistent,which provides a reference for the study of fatigue problems of fully assembled steel truss-concrete composite beams.

关 键 词：全装配钢桁组合梁 PCSS剪力连接件 非连续传力模型 焊缝疲劳问题 试验研究 

分 类 号：U446.3[建筑科学—桥梁与隧道工程]