考虑裂纹长度和角度特征的横隔板焊趾开裂规律分析  

Analysis of Crack Law of Diaphragm Welding Toe Considering Crack Length and Angle Characteristics

作　　者：崔建伟 傅中秋[1] 曹雪坤 高玉强 CUI Jianwei;FU Zhongqiu;CAO Xuekun;GAO Yuqiang(College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学土木与交通学院,南京210098

出　　处：《武汉理工大学学报(交通科学与工程版)》2025年第1期129-134,141,共7页Journal of Wuhan University of Technology(Transportation Science & Engineering)

基　　金：国家重点研发计划资助项目(2017YFE0128700);江苏省交通运输科技与成果转化项目(2022Y19)。

摘　　要：文中通过有限元软件建立钢桥面板节段模型,针对横隔板焊趾细节,分别建立未开裂时和开裂后不同长度和角度的带裂纹子模型,来分析对比不同特征裂纹的扩展规律.研究结果表明:横隔板焊趾易从边缘开裂,沿厚度方向贯穿横隔板;横隔板焊趾贯穿裂纹呈Ⅱ、Ⅲ型为主的复合型裂纹扩展,随裂纹角度增大,裂纹尖端等效应力强度因子幅先增大后趋于稳定,最不利荷载工况下45°附近裂纹的扩展速率达到最快,建议实桥上优先维修裂纹角度超过40°以上的裂纹;随长度增加裂纹扩展可分为四个阶段,40 mm以下时裂纹扩展速率近似线性增大,40~80 mm裂纹扩展速率缓慢增大,80~130 mm裂纹扩展趋于稳定,130 mm后裂纹进一步加速扩展,建议在裂纹长度达到80 mm前尽早采取维修措施.The segmental model of steel bridge deck was established by finite element software.According to the weld toe details of diaphragm,sub-models with cracks with different lengths and angles were established respectively before and after cracking to analyze and compare the propagation laws of cracks with different characteristics.The results show that the welding toe of diaphragm is easy to crack from the edge and penetrate through diaphragm along the thickness direction.The penetration crack of diaphragm welding toe is a compound crack propagation with typeⅡandⅢas the main types.With the increase of crack angle,the amplitude of equivalent stress intensity factor at crack tip first increases and then tends to be stable,and the crack propagation rate near 45 reaches the fastest under the most unfavorable load condition.It is suggested that cracks with crack angle over 40 should be maintained first on real bridges.With the increase of the length,the crack growth can be divided into four stages.The crack growth rate increases approximately linearly below 40 mm,slowly increases at 40~80 mm,tends to be stable at 80~130 mm,and further accelerates after 130 mm.It is suggested that maintenance measures should be taken as soon as possible before the crack length reaches 80 mm.

关 键 词：钢桥面板 横隔板焊趾 裂纹 应力强度因子 开裂规律 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]