摘要
为研究斜拉桥轴向力作用下顶板-U肋焊缝裂纹的扩展特征以及裂纹对顶板局部受力的影响,建立了全桥模型模拟斜拉桥的成桥状态.通过ABAQUS中sub-model功能将成桥状态下的位移和受力作为节段模型的边界条件并在节段模型中添加车辆荷载,分析带裂顶板的最不利荷载工况,在最不利荷载工况下分析了不同长度顶板-U肋焊缝贯穿裂纹的扩展特征以及其对顶板-U肋焊缝细节局部受力的影响.结果表明:考虑斜拉桥轴力作用,顶板-U肋焊缝焊趾和焊根处贯穿裂纹均为Ⅰ型为主的Ⅰ-Ⅱ-Ⅲ型复合裂纹,轴向力作用对裂纹扩展影响较小;同一U肋中顶板-U肋焊缝焊根开裂会增加未开裂侧顶板应力,降低开裂侧焊缝应力;焊趾开裂会降低开裂侧顶板焊根应力,增加U肋焊趾应力和未开裂侧焊缝应力.
In order to study the crack propagation characteristics of the roof-u rib weld under the axial force of the cable-stayed bridge and the influence of the crack on the local stress of the roof,a full bridge model was established to simulate the completed state of the cable-stayed bridge.The displacement and stress in the completed state were taken as the boundary conditions of the segment model through the sub model function in ABAQUS,and the vehicle load was added to the segment model.The most unfavorable load case of Cracked Roof was analyzed.Under the most unfavorable load case,the propagation characteristics of through cracks in roof-u-rib welds with different lengths and their influence on the local stress of roof-u-rib welds were analyzed.The results show that considering the axial force of cable-stayed bridge,the through cracks at the weld toe and root of roof-u rib weld are mode I-II-III composite cracks,and the axial force has little effect on the crack propagation;The cracking of the weld root between the top plate and the U rib in the same U rib will increase the stress of the top plate on the uncracked side and reduce the stress of the weld on the cracked side;Weld toe cracking will reduce the root stress of the roof on the cracked side,and increase the weld toe stress of U-rib and the weld stress on the uncracked side.
作者
高玉强
傅中秋
吉伯海
曹雪坤
GAO Yuqiang;FU Zhongqiu;JI Bohai;CAO Xuekun(College of Civil and Transportation Engineering,Hehai University,Nanjing 210098,China)
出处
《河南大学学报（自然科学版）》
CAS
2023年第4期472-481,共10页
Journal of Henan University:Natural Science
基金
国家重点研发计划政府间重点专项项目(2017YFE0128700)
关键词
斜拉桥
钢桥面板
顶板贯穿裂纹
焊缝应力
cable-stayed bridge
steel deck
roof through crack
stress at weld
