高性能桥梁耐候钢典型焊缝接头疲劳性能试验研究  

Experimental Study on Fatigue Properties of Typical Weld Joints of Specialist High-Performance Weathering Steel for Bridge

作　　者：赵而年 孙洪斌 张鑫[1] 周强[3] ZHAO Er-nian;SUN Hong-bin;ZHANG Xin;ZHOU Qiang(Key Laboratory of Building Structural Retrofitting and Underground Space Engineering(Shandong Jianzhu University),Ministry of Education,Jinan 250101,China;Shandong Railway Investment Holding Group Co.,Ltd.,Jinan 250102,China;Hubei Key Laboratory of Roadway Bridge and Structure Engineering,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]山东建筑大学建筑结构加固改造与地下空间工程教育部重点实验室,山东济南250101 [2]山东铁路投资控股集团有限公司,山东济南250102 [3]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

出　　处：《桥梁建设》2022年第2期75-81,共7页Bridge Construction

基　　金：国家自然科学基金项目(52038006)。

摘　　要：为了解高性能桥梁耐候钢典型焊缝接头的疲劳特性,设计、制作Q370qNH高性能桥梁耐候钢对接焊缝、T形焊缝和十字形焊缝接头试件进行疲劳试验。分析3类焊缝接头试件疲劳破坏模式、疲劳寿命与疲劳强度,并将试验拟合的S~N对数曲线与现行规范结果进行对比;基于收集的141个疲劳试验结果,分析高性能桥梁耐候钢典型焊缝接头和传统结构钢同类焊缝接头疲劳特性的差异。结果表明:3类耐候钢焊缝接头均发生了焊趾处的疲劳失效破坏,设计、施工时应重点关注;随着加载应力幅的增加,3类接头的疲劳寿命按幂指数形式逐渐降低;在与规范相同保证率条件下,计算的桥梁耐候钢对接焊缝疲劳强度分别是《钢结构设计标准》(GB 50017—2017)的1.30倍、《铁路桥梁钢结构设计规范》(TB 10091—2017)的1.14倍;T形焊缝接头表现出最好的抗疲劳性能,现行规范中对其疲劳强度的评估偏于保守;十字形焊缝接头95%保证率S~N对数曲线和《钢结构设计标准》设计曲线吻合较好。The Q370qNH high-performance steel specimens with butt weld joint,T-shaped weld joint and cruciform weld joint were prepared for fatigue tests,to examine the fatigue properties of the typical weld joints of specialist high-performance weathering steel for bridge.The failure modes,fatigue life and fatigue strength of the three types of weld joints were analyzed,and the S~N curves fitted by the tests were compared with those suggested by the current codes.Based on a number of 141 fatigue test results collected,comparisons were made to find out the difference between fatigue properties of weld joints of same type in the specialist high-performance weathering steel for bridge and the common structural steel.Fatigue failure was observed at welding toes of all types of weld joints in three weathering steel specimens,which should be given great concern in design and construction.As the loading stress range increased,the fatigue lives of the three types of weld joints steadily decreased in an exponential manner.Keeping the same level of guarantee rate suggested by the specifications,the calculated fatigue strength of butt weld joint of specialist weathering steel for bridge is 1.3 and 1.14 times of the values listed in the Standard for Design of Steel Structures(GB 50017-2017)and Code for Design on Steel Structure of Railway Bridge(TB 10091-2017),respectively.The T-shaped weld joint performs best in terms of fatigue resistance,but the fatigue strength assessments of this type of weld joint in current codes are considered conservative.The S~N curve of the cruciform weld joint with 95%guarantee rate complies well with the design curves given by the Standard for Design of Steel Structures.

关 键 词：桥梁钢 高性能耐候钢 焊缝接头形式 疲劳试验 S~N曲线 疲劳强度 

分 类 号：U441.4[建筑科学—桥梁与隧道工程] TU391[交通运输工程—道路与铁道工程]