两桁悬索加劲钢桁梁桥特殊节点缩尺模型静载试验研究  

Scaled Static Model Test on Special Joints of Two-Main-Truss Stiff Suspension Reinforced Steel Truss Bridge

作　　者：魏思斯 耿波[1] 尚军年[1] 安永日 郑植 WEI Si-si;GENG Bo;SHANG Jun-nian;AN Yong-ri;ZHENG Zhi(State Key Laboratory of Bridge Engineering Structural Dynamics,China Merchants Chongqing Communications Research&Design Institute Co.,Ltd.,Chongqing 400067,China;School of Civil Engineering,Guizhou University,Guiyang 550025,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]招商局重庆交通科研设计院有限公司桥梁工程结构动力学国家重点实验室,重庆400067 [2]贵州大学土木工程学院,贵州贵阳550025 [3]重庆大学土木工程学院,重庆400045

出　　处：《桥梁建设》2022年第5期52-59,共8页Bridge Construction

基　　金：国家重点研发计划项目(2019YFB1310400);交通运输行业重点科技项目(2020-MS1-007)。

摘　　要：重庆曾家岩嘉陵江大桥为主跨270 m的两桁悬索加劲连续钢桁梁桥,该桥刚性悬索与上弦杆连接节点(特殊节点)涉及的杆件众多、规模大、结构构造和受力复杂。为验证该桥特殊节点的合理性,研究了该节点的静力性能,基于有限元分析,设计制作相似比为1∶2.5的特殊节点局部模型进行静载试验(最大加载至1.4倍设计荷载),分析模型各杆件端部位移以及关键部位的应力分布。结果表明:试验模型各剖面测点实测应力分布规律与有限元计算结果基本吻合;在1.4倍设计荷载下,实测应力低于钢材的容许应力;试验过程中,缩尺模型各杆端位移及各测点应力均随荷载增大基本呈线性趋势增长,结构整体处于弹性阶段。该桥特殊节点具有足够的安全储备,设计合理。The Zengjiayan Jialingjiang River Bridge in Chongqing is a two-main-truss stiff suspension reinforced steel truss bridge with a main span of 270 m.The configuration and load-bearing behavior of its large-scale joints connecting stiff suspension and top chord(namely the special joints) involving multiple members are complex.To verify the design of this special joint,its static behavior was studied.Based on results from finite element analysis,a 1∶2.5 scaled model was designed and prepared.A static load test was conducted(the maximum loads applied were 1.4 times of design loads).The displacement at the end of each member and the strain distribution at the key regions of the model were analyzed.The results indicate that good agreement exists between the experimental and theoretical stress distribution along the measurement points on each section.Under 1.0 and 1.4 times of the design loads,the stress of each measurement point is below the allowable stress.Throughout the test,both the displacement at the end of each member and the stress of measurement points increase linearly as loads go up.The structure remains elastic under test loads.The special joints have sufficient safety margin.The design of special joints of Zengjiayan Bridge was verified.

关 键 词：悬索加劲钢桁梁桥 特殊节点 静力性能 应力 位移 缩尺模型试验 有限元法 

分 类 号：U448.36[建筑科学—桥梁与隧道工程] U441.5[交通运输工程—道路与铁道工程]