正交异性钢桥面板的贯穿型疲劳裂纹扩展特性分析  

Analysis of Propagation Behavior of Penetrating Cracks in Orthotropic Steel Bridge Deck

作　　者：刘扬[1,2] 王梓桐[1] 鲁乃唯 王鸿浩[1] LIU Yang;WANG Zitong;LU Naiwei;WANG Honghao(Changsha University of Science and Technology,Changsha,Hunan 410114,China;Hunan University of Technology,Zhuzhou,Hunan 412000,China)

机构地区：[1]长沙理工大学,湖南长沙410114 [2]湖南工业大学,湖南株洲412000

出　　处：《公路工程》2023年第1期29-38,共10页Highway Engineering

基　　金：国家自然科学基金项目(51908068);国家自然科学基金项目(52178108);湖南省自然科学基金项目(2021JJ30720);湖南省教育厅创新平台开放基金项目(19K002)。

摘　　要：为了研究钢桥面顶板与U肋焊缝处贯穿型裂纹的应力强度因子和扩展行为,结合线弹性断裂力学理论与ABAQUS-FRANC 3D交互技术,建立了钢桥面顶板焊缝处贯穿型裂纹的数值分析模型,开展了不同初始长度贯穿裂纹应力强度因子的分析和单一长贯穿型裂纹扩展模拟的研究。对比分析了顶板与U肋焊缝细节处不同长度贯穿型裂纹的裂尖应力强度因子,揭示了初始裂纹尺寸与基础裂纹的应力强度因子之间的变化规律,考虑KⅡ、KⅢ对单一长贯穿型裂纹扩展的影响。数值分析结果表明:在规定荷载作用下,基础裂纹尺寸与初始应力强度因子成正比;随着贯穿型裂纹的桥纵向开裂,扩展趋势稳定;对比只考虑I型开裂贯穿型裂纹,引入KⅡ、KⅢ贯穿型裂纹扩展速率明显减缓:贯穿裂纹初始长度相同的情况下,仅考虑K I的裂纹平均扩展速率为4.097 mm·c^(-5),考虑KⅡ、KⅢ的裂纹平均扩展速率为1.565 mm·c^(-5),扩展速率抑制效果明显。In order to study the stress intensity factor and growth behavior of the penetrating crack at the weld of the steel bridge deck roof and U rib,a numerical analysis model of the penetrating crack at the weld of the steel bridge deck roof was established by combining the linear elastic fracture mechanics theory and ABAQUS-FRANC 3D interaction technology.The stress intensity factors of different initial lengths of through-crack and the simulation of single through-crack propagation were studied.Considering the effect of KⅡ、KⅢon propagation,the crack tip STRESS intensity factors of different lengths of penetrating cracks at the details of roof and U-rib weld were compared and analyzed,and the variation rule between the initial crack size and the base crack stress intensity factors was revealed.The numerical results show that the crack size of the foundation is proportional to the initial stress intensity factor under the specified load.The longitudinal cracking of the bridge with penetrating crack increases and the propagation trend is stable.Compared with only the type I cracking through crack,the introduction of KⅡ、KⅢthrough crack growth rate is significantly slowed down:under the same initial length of the penetrating crack,the average crack growth rate of K I is 4.097 mm·c^(-5),and that of KⅡ、KⅢis 1.565 mm·c^(-5),which shows obvious inhibition effect on the growth rate.

关 键 词：正交异性钢桥面板 顶板-U肋焊缝 贯穿型裂纹 裂纹扩展 

分 类 号：U443.31[建筑科学—桥梁与隧道工程]