正交异性钢桥面板横隔板弧形切口切割残余应力分析  

Research on Cutting Residual Stresses in Diaphragm Cutout of Orthotropic Steel Deck

作　　者：陈卓异[1] 熊永明 李传习[1] CHEN Zhuo-yi;XIONG Yong-ming;LI Chuan-xi(Key Laboratory for Safety Control of Bridge Engineering,Ministry of Education,Changsha University of Science&Technology,Changsha 410144,China;State Key Laboratory for Health and Safety of Bridge Structures,Wuhan 430034,China;China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China)

机构地区：[1]长沙理工大学桥梁工程安全控制教育部重点实验室,湖南长沙410114 [2]桥梁结构健康与安全国家重点实验室,湖北武汉430034 [3]中铁大桥科学研究院有限公司,湖北武汉430034

出　　处：《桥梁建设》2020年第6期46-52,共7页Bridge Construction

基　　金：国家自然科学基金项目(51708047,51778069);湖南省自然科学基金项目(2019JJ50670);湖南省教育厅优秀青年项目(19B013)。

摘　　要：为分析正交异性钢桥面板横隔板弧形切口处残余应力分布特征,研究其疲劳易裂原因,以佛山平胜大桥为背景,采用Abaqus有限元软件建立横隔板切割模型,模拟横隔板切割成型过程,探究横隔板切割温度、应力演变规律及残余应力分布特点。结果表明:热切割产生的残余应力主要集中于切割线附近;横隔板弧形切口弧段中部横向残余应力达288.2 MPa,而自由边易开裂处横向残余应力较低,纵向残余拉应力峰值为373.4 MPa;横隔板内距切割自由边14.5 mm处不仅有较高的纵向残余拉应力,且横向残余拉应力峰值达199.3 MPa。热切割在自由边产生较高的残余拉应力,在轮载联合作用下产生的拉应力循环是导致其形成初始疲劳裂纹的原因之一,对弧形切口的疲劳寿命有重要影响。To study the mechanism of fatigue cracks occurring in the orthotropic steel decks,the characteristics of residual stress distribution in the diaphragm cutout of orthotropic steel deck are analyzed.The diaphragm model based on the Foshan Pingsheng Bridge was proposed,and the flame cutting process in diaphragm manufacturing was analyzed by Abaqus.For researching the cutting residual stresses in the diaphragm cutout,the evolution of temperature and stress distribution was carefully observed.The results show that the cutting residual stress is distributed near the cutting line.The residual stress along transverse direction is lower than that along longitudinal direction,the transverse residual stress is about 288.2 MPa at the middle of cutout notch,with lower transverse residual stress in the crack-sensitive region along the free side,and the longitudinal residual stress is 373.4 MPa.The distribution of residual stress field in transverse diaphragm is very complex,at 14.5 mm from the cutting free edge,the longitudinal residual tensile stress is significant while the measured transverse residual stress can also reach 199.3 MPa.The high residual tensile stress produced by flame cutting has an important influence on the fatigue life of the diaphragm cutouts,the cycle of tensile stress created by the coupling effect of traffic load and cutting residual stress is one of the causes of the fatigue crack.

关 键 词：正交异性钢桥面板 横隔板 U肋 热切割 温度场 残余应力 疲劳 有限元法 

分 类 号：U441.5[建筑科学—桥梁与隧道工程] U443.32[交通运输工程—道路与铁道工程]