钢桁桥节点构造演变及其疲劳评估热点应力法  

Joint Structure Evolution and a Hot Stress Method for Assessing Fatigue of Steel Truss Bridge

作　　者：于丰菘 周洪福 姜磊[1] 刘彬 YU Feng-song;ZHOU Hong-fu;JIANG Lei;LIU Bin(School of Highway,Chang’an University,Xi’an Shaanxi 710064,China;Qingdao Geotechnical Investigation and Surveying Research Institute,Qingdao Shandong 266033,China;CSCEC AECOM Consultants Co.,Ltd.,Lanzhou Gansu 730000,China)

机构地区：[1]长安大学公路学院,陕西西安710064 [2]青岛市勘察测绘研究院,山东青岛266033 [3]中国市政工程西北设计研究院有限公司,甘肃兰州730000

出　　处：《公路交通科技》2023年第6期126-139,共14页Journal of Highway and Transportation Research and Development

基　　金：陕西省留学人员科技活动择优项目(2021-11);甘肃省住房和城乡建设厅建设科技项目(JK2023-31);中央高校基本科研业务费专项项目(300102213207);中国市政工程西北设计研究院有限公司科技计划项目(XBSZKY2206)。

摘　　要：为统一钢桁桥节点各疲劳构造细节,形成节点疲劳评估热点应力法,完善我国现行钢桁桥节点疲劳设计规范体系,从钢桁桥节点演变出发,选取当前钢桁桥常用的3类节点,包含栓焊整体节点、全焊整体节点和全焊相贯节点,总结笔者团队及相关学者多年理论、试验和数值成果,给出了各类节点热点应力S-N曲线。采用线弹性叠加理论将各类节点所受的复杂荷载工况简化为4种基本荷载工况,包含弦杆和腹杆平衡轴力、弦杆轴力、弦杆弯矩和腹杆平衡轴力及其相应组合,提出了相应的节点应力集中系数计算方法。结果表明:栓焊和全焊整体节点具有相似的焊接疲劳构造细节,统计了国内外疲劳试验数据共计1332个,提出了采用疲劳细节类别为90 MPa的一条热点应力S-N曲线作为其抗力曲线,统计了包括圆形钢管节点、圆形钢管混凝土节点、矩形钢管节点和矩形钢管混凝土节点在内的疲劳试验数据177个,提出了全焊相贯节点可采用疲劳细节类别为85 MPa的一条热点应力S-N曲线作为其抗力曲线;对于栓焊整体节点和全焊整体节点,提出了K型和KT型节点应力集中系数计算公式,对于全焊相贯节点,分别给出了圆形和矩形钢管混凝土K型节点应力集中系数计算公式,建立了整体节点和相贯节点焊趾处应力集中程度和几何无量纲参数的关系。In order to unify the fatigue structural details of steel truss bridge joints,form a hot spot stress method for joint fatigue assessment,and improve the current joint fatigue design specification system for steel truss bridges in China,by tracing the evolution of steel truss bridge joints,selecting 3 types of joints commonly used in steel truss bridges(bolted-welded integral joint,fully-welded integral joint,fully-welded intersecting joint)and summarizing the theoretical,experimental and numerical results of the author’s team and relevant scholars for many years,the hot spot stress S-N curves of various joints are provided.The complex load conditions of various joints are simplified into 4 basic load conditions(the balance axial force of chord and belly,chord axial force,chord bending moment and belly axial force,and their corresponding combinations)by using linear elastic superposition theory,and the corresponding calculating methods of stress concentration factors in these joints are proposed.The result shows that(1)The bolted-welded and full-welded integral joints share similar weld fatigue construction details.A total of 1332 fatigue test data points from both domestic and international sources are statistically analyzed,a hot spot stress S-N curve with a fatigue detail category of 90 MPa is proposed as the resistance curve for these joint types.177 fatigue test data including circular steel tube joints,circular steel tube concrete-filled joints,rectangular steel tube joints and rectangular steel tube concrete-filled joints are statistically analyzed.A hot spot stress S-N curve with a fatigue detail category of 85 MPa is proposed as the resistance curve for fully welded intersecting joints.(2)For bolted-welded integral joints and full-welded integral joints,the formulas for calculating the stress concentration coefficient of K-type and KT-type joints are proposed.For fullg-welded intersecting joints,the formulas for calculating the stress concentration coefficient of circular and rectangular CFST K-type joi

关 键 词：桥梁工程 疲劳性能 热点应力法 钢桁桥节点 应力集中系数 

分 类 号：U441.4[建筑科学—桥梁与隧道工程]