钢桥面板盖板-U肋焊缝平面内双裂纹扩展研究  

Study on double crack propagation law of orthotropic steel bridge deck cover-U rib welding seam

作　　者：刘嘉[1] 刘明露 颜攀 涂建维[1] LIU Jia;LIU Minglu;YAN Pan;TU Jianwei(Hubei Key Laboratory of Roadway Bridge and Structure Engineering,Wuhan University of Technology,Wuhan 430070,China;School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430070,China;China Light Industry Wuhan Design and Engineering Co.Ltd.,Wuhan 430060,China)

机构地区：[1]武汉理工大学道路桥梁与结构工程湖北省重点实验室,湖北武汉430070 [2]武汉理工大学土木工程与建筑学院,湖北武汉430070 [3]中国轻工业武汉设计工程有限责任公司,湖北武汉430060

出　　处：《华中科技大学学报（自然科学版）》2021年第9期107-113,共7页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51978550,51108363)。

摘　　要：对大跨度桥梁正交异性钢桥面板盖板-U肋焊接部位平面内双裂纹扩展规律进行研究,基于单裂纹扩展理论,采用相互作用积分法计算裂纹尖端应力强度因子和最大能量释放率(MERR)准则确定扩展方向,根据等效裂纹前缘原则研究双裂纹扩展到一定阶段后的融合及失效的全过程,并以安庆长江大桥正交异性钢桥面板盖板-U肋焊趾部位为研究背景,探寻其平面内双裂纹的扩展发展规律,获取双裂纹扩展下的疲劳寿命.结果显示:焊趾处平面内双裂纹是由I型主导的Ⅰ-Ⅱ-Ⅲ复合型裂纹扩展融合过程;两个初始裂纹在各自区域内呈单裂纹扩展达到融合,融合后裂纹长轴方向扩展速度较快,最终形成新的单裂纹直至构件损坏.The in-plane double crack propagation law of the welded part of the long-span orthotropic steel deck cover plate and Urib was studied.Based on the single crack propagation theory,the interaction integral method was used to calculate the crack tip stress intensity factor and the maximum energy release rate criterion to determine the propagation direction.According to the principle of equivalent crack front,the whole process of fusion and failure of double cracks after a certain stage was studied.And based on the research background of the orthotropic steel deck cover-U-rib weld toe of the Anqing Yangtze River Bridge,the in-plane double crack propagation and development law were explored,and the fatigue life under the double crack propagation was obtained.The results show that the in-plane double cracks at the weld toe are the I-Ⅱ-Ⅲcompound crack propagation and fusion process dominated by type I.The two initial cracks grow as single cracks in their respective areas to achieve fusion.After fusion,the cracks grow faster in the long axis direction,and finally a new single crack is formed until the component is damaged.

关 键 词：钢桥面板盖板 多尺度 等效裂纹前缘 双裂纹 裂纹融合 应力强度因子 

分 类 号：U441.4[建筑科学—桥梁与隧道工程]