板桁结合悬索加劲钢桁梁桥特殊节点受力行为  

Force Behavior of Special Joints of Plate-Girder Combined Steel Truss Bridge Reinforced by Suspension Cables

作　　者：魏思斯 耿波[1] 尚军年[1] 郑植 WEI Sisi;GENG Bo;SHANG Junnian;ZHENG Zhi(State Key Laboratory of Bridge Engineering Structural Dynamics,China Merchants Chongqing CommunicationsResearch&Design Institute Co.,Ltd.,Chongqing 400067,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]重庆大学土木工程学院,重庆400045

出　　处：《重庆交通大学学报（自然科学版）》2023年第1期1-8,共8页Journal of Chongqing Jiaotong University(Natural Science)

基　　金：国家重点研发计划项目(2017YFC0806000)。

摘　　要：为了研究板桁结合悬索加劲连续钢桁梁桥加劲弦与上弦杆连接部位特殊节点的静力受力行为,依托重庆曾家岩嘉陵江大桥建立了全桥三维多尺度有限元模型,并通过缩尺模型试验对有限元分析结果进行验证,对特殊节点在最不利荷载组合作用下的受力状况进行了研究。研究结果表明:特殊节点中加劲弦与上弦杆交界处附近应力较大,且应力分布较复杂,为重点关注部位;特殊节点总体Von Mises应力在198.0 MPa以内,特殊节点各杆件Von Mises应力均小于钢材的强度设计值,结构具有足够的安全储备;正交异性桥面系参与主梁竖向弯曲受力,上层桥面系传递的内力约占纵桥向、横桥向上合力的34%和33%;荷载由跨中向支点经过特殊节点的传递,钢桥面板、上弦杆、竖腹杆以及斜腹杆承担的力逐渐传递给了加劲弦,引入加劲弦来提高梁高,抵抗主梁截面的竖向弯矩。有限元分析结果验证了重庆曾家岩嘉陵江大桥特殊节点的可靠性,也为类似节点的研究与设计提供参考。In order to investigate the static force behaviour of special joints at the connection between the top chord and stiffening chord of plate-girder combined continuous steel truss girder stiffened by suspension cables,a three-dimensional multi-scale finite element model of the whole bridge was established,which was based on Chongqing Zengjiayan Jialing River Bridge.The results of finite element analysis were verified by the scaled model test,and the stress condition of special joints under the most unfavorable load combination was studied.The research results indicate that the stress near the connection between the stiffening chord and the top chord is relatively large and its distribution is complex,which is the focus of the study.The Von Mises stress of the majority of special joints is below 198.0 MPa.The Von Mises stress of each member of the special joint is less than the strength design value of the steel,and the structure has sufficient safety reserves.The orthotropic steel deck participates in the vertical bending of main girder.The internal forces transmitted by the upper deck system account for about 34%and 33%of the combined forces in the longitudinal and transverse directions.The load is transferred from the midspan to the fulcrum through the special joint,and the force borne by the steel deck,top chord,vertical web and diagonal web is gradually transferred to the stiffening chord.The stiffening chord is introduced to improve the beam height and resist the vertical bending moment of the main beam section.Results of finite element analysis verify the reliability of the special joints of the Zengjiayan Jialing River Bridge,which can also serve as a reference for future research and design of similar structures.

关 键 词：桥梁工程 悬索加劲连续钢桁梁 板桁结合钢桥面板 静力受力行为 多尺度有限元模型 

分 类 号：U441[建筑科学—桥梁与隧道工程]