钢管混凝土桁肋内栓钉K型节点应力集中特性  

Stress concentration characteristics of concrete-filled steel tubular truss-rib K-joint with inner studs

作　　者：刘君平[1] 杨倩 刘华龙 杨意图 陈宝春[1] LIU Jun-ping;YANG Qian;LIU Hua-long;YANG Yi-tu;CHEN Bao-chun(College of Civil Engineering,Fuzhou University,Fuzhou 350116,Fujian,China;CCCC second Harbor Engineering Co.,Ltd.,Wuhan 430014,Hubei,China)

机构地区：[1]福州大学土木工程学院,福建福州350116 [2]中交第二航务工程局有限公司,湖北武汉430014

出　　处：《交通运输工程学报》2024年第6期106-120,共15页Journal of Traffic and Transportation Engineering

基　　金：国家自然科学基金项目(52078136)。

摘　　要：为深入研究设置内栓钉对钢管混凝土桁肋K型节点应力分布的影响,开展应力集中特性试验,对比测试了不设置内栓钉的节点热点应力及应力集中系数;建立内栓钉节点的精细有限元模型,分析了内栓钉布置形式和几何尺寸对应力集中系数的影响;基于试验和有限元参数分析结果,提出了内栓钉的建议布置形式以及节点应力集中系数计算方法。研究结果表明:内栓钉没有改变节点的热点应力分布规律,最大应力集中系数均出现在受拉相贯区域主管侧冠点处,但节点的应力集中程度被有效减小;与不设置内栓钉节点相比,设置内栓钉节点的热点应力最大值降低了17.38%;受拉相贯焊缝区域主管侧、相应支管侧的整体应力集中系数分别平均减小了24.20%和12.30%,主管环向截面应力降低16.2%;内栓钉对受压相贯焊缝区域的应力分布和应力集中程度的影响很小,在7%以内;应力集中系数受内栓钉环向排列角度和轴向排列间距的影响较大,受内栓钉几何尺寸的影响较小;建议内栓钉布置在主管轴向距节点中心至截面两侧各约支管直径的2.7倍范围内,环向布设在连接支管侧的圆心角[-60°,60°]内,且相邻内栓钉间距不小于内栓钉直径的6倍但不超过400 mm;引入内栓钉轴向排列影响系数及环向排列影响系数的应力集中系数计算公式具有较高计算精度,可用于评估钢管混凝土桁肋内栓钉K型节点的疲劳性能。To further study the influence of setting inner studs on the stress distribution of concrete-filled steel tubular truss-rib K-joints,a test on the stress concentration characteristics was conducted.The hot spot stress and stress concentration factor of joints without inner studs were compared and tested.The fine finite element models of the joints with inner studs were established.The influences of the arrangement and geometric dimensions of inner studs on the stress concentration factor were analyzed.Based on the results of the test and the finite element parameter analysis,the recommended layout of the inner stud and the calculation method of the stress concentration factor of the joints were proposed.Research results show that the hot spot stress distribution of the joints is not changed with the inner studs,and the maximum stress concentration factor is found at the crown point of the main tube in the tensile weld area,but the stress concentration degree of the joints effectively reduces.Compared with the joint without inner studs,the maximum hot spot stress of the joint with inner studs reduces by 17.38%.The overall stress concentration factors of the main tube side and the corresponding branch tube side in the tensile weld area decrease by 24.20%and 12.30%on average,respectively,and the circumferential section stress of the main tube decreases by 16.2%.The influence of inner studs on the stress distribution and stress concentration in the compressive weld area is so slight to be within 7%.The stress concentration factors are affected greatly by the circumferential arrangement angle and the axial arrangement spacing of inner studs but less by the geometrical dimension of inner studs.The inner studs are suggested to be arranged within the range of approximately 2.7 times the diameter of the branch tube from the center of the joint to each side section in the axial direction of the main tube.The circumferential arrangement is within the range of[-60°,60°]of the central angle of connecting branch tube side.At

关 键 词：桥梁工程 钢管混凝土拱桥 节点 内栓钉 应力集中系数 计算公式 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]