正交异性钢桥面板典型细节的疲劳损伤分析  

Fatigue Damage Analysis of Typical Details of Orthotropic Steel Bridge Deck

作　　者：林上顺 LIN Shang-shun(College of Civil Engineering,Fujian University of Technology,Fuzhou 350118,China;Fujian Provincial Key Laboratory of Advanced Technology and Information in Civil Engineering(Fujian University of Technology),Fuzhou 350118,China)

机构地区：[1]福建工程学院土木工程学院,福建福州350118 [2]福建省土木工程新技术与信息化重点实验室(福建工程学院),福建福州350118

出　　处：《桥梁建设》2020年第4期54-60,共7页Bridge Construction

基　　金：福建省自然科学基金项目(2019J01779);福建交通科技项目(201707)。

摘　　要：为研究正交异性钢桥面板典型疲劳细节在单轮荷载作用下的应力及疲劳损伤度,以福州长门特大桥为背景,采用ABAQUS有限元软件建立钢桥面板节段模型和3处易开裂部位(横隔板-U肋焊缝、横隔板处和横隔板间的顶板-U肋焊缝)的子分析模型,分析车轮荷载作用位置变化时疲劳细节的应力时程;并采用雨流计数法分析各细节处的应力幅,对疲劳细节进行疲劳损伤度分析。结果表明:单轮荷载顺桥向位于相邻横隔板间时,对横隔板处的顶板-U肋焊缝应力产生较大影响;荷载横向分布接近±750 mm时,疲劳细节的应力时程曲线较为平缓,荷载对其应力的影响较小;疲劳损伤最大的是横隔板处的顶板-U肋焊缝焊根部位,该部位易产生疲劳破坏。建议在该部位增设钢角撑或钢板等,以降低该位置的应力幅和疲劳损伤度,提高结构的耐久性。To examine the stresses and fatigue damage degree of typical fatigue details in orthotropic steel bridge deck under the action of single-wheel load,the Changmen Bridge in Fuzhou was taken as the study background.The segmental model of the steel deck and three sub-models for analysis were established by ABAQUS,to analyze the time history of stresses in the fatigue details corresponding to the variation of acting location of wheel loads.The sub-models contain fatigue damages in the weld of diaphragm and U-rib,at diaphragms and in the weld of top plate(between diaphragms)and U-rib,respectively.The stress amplitude of each fatigue detail was analyzed by the rainflow counting method,based on which the degree of fatigue damages of the fatigue details was analyzed.The results show that the single-wheel load located between two adjacent diaphragms along the bridge length can exert great influence on the stresses in the weld of top plates(at diaphragms)and U-rib.When the transverse distribution of loads approximates±750 mm,the time history curves of stresses in the fatigue details are relatively flat,suggesting that the influence of loads on the stresses is minimal.The most severe fatigue damage occurs at the toes of the welds of top plates(at diaphragms)and U-ribs,where are susceptible to fatigue damage.It is suggested that the toes of the welds of top plates(at diaphragms)and U ribs be strengthened with steel angle struts or steel plates,so as to reduce the stress amplitude and degree of fatigue damage and improve the durability of the structure.

关 键 词：正交异性钢桥面板 疲劳 焊缝 子分析模型 车轮荷载 损伤度分析 有限元法 

分 类 号：U443.32[建筑科学—桥梁与隧道工程] U441.4[交通运输工程—道路与铁道工程]