南昌洪州大桥主塔二阶效应分析  

Second Order Effect Analysis of Main Tower of Nanchang Hongzhou Bridge

作　　者：顾奕伟 胡方健 李贵峰 GU Yi-wei;HU Fang-jian;LI Gui-feng(Shanghai Urban Construction Design&Research InstituteCo.,Ltd.,Shanghai 200125,China;Key Laboratory of Civil Engineering Safety&Durability,Ministry of Education,Tsinghua University,Beijing 100084,China)

机构地区：[1]上海市城市建设设计研究总院(集团)有限公司,上海200125 [2]清华大学土木工程安全与耐久教育部重点实验室,北京100084

出　　处：《中国市政工程》2024年第5期20-25,157,共7页China Municipal Engineering

基　　金：上海市社会发展科技攻关项目(23DZ1202905);江西省交通运输厅重点工程科技项目(2024ZG010);2024年度隧道股份城市更新科创新中心项目(子课题2)。

摘　　要：南昌洪州大桥主桥为跨度(50+120+252+120+50) m的钢-混凝土组合梁双塔自锚式悬索桥,半漂浮体系。主塔为门式桥塔,采用“昌”字造型,承台以上名义塔高为116.291 m。为研究洪州大桥主塔在压弯作用下的二阶效应与极限承载力,采用开源有限元软件OpenSees建立主塔非线性梁柱单元模型,考虑几何和材料非线性,计算主塔在设计荷载作用下的偏心距增大系数与极限承载力,并对不同配筋情况下,主塔的极限承载力进行计算分析,提出了优化配筋方案并运用于工程实施。进一步地,文章对现行规范中,关于偏心距增大系数计算的合理性做探讨,提出1种适用于大型压弯构件的偏心距增大系数计算方法。相比于原规范公式,文章提出的算法与有限元仿真结果的吻合度更高,可用于超高桥塔等大型压弯构件的设计。The main bridge of Hongzhou Bridge in Nanchang is a steel-concrete composite beam double tower self anchored suspension bridge with a span of(50+120+252+120+50)m and a semifloating system.The main tower is a portal bridge tower with a昌-shaped style,and the nominal tower height above the pedestal is 116.291 m.To study the second-order effect and ultimate bearing capacity of the main tower of Hongzhou Bridge under compression bending,an open source finite element software OpenSees is used to establish a nonlinear beam column element model of the main tower.Considering geometric and material nonlinearity,calculate the eccentricity increase coefficient and ultimate bearing capacity of the main tower under design load,and analyze the ultimate bearing capacity of the main tower under different reinforcement conditions.Propose an optimized reinforcement scheme and apply it to engineering implementation.Furthermore,the article explores the rationality of calculating the eccentricity increase coefficient in current standards and proposes a method for calculating the eccentricity increase coefficient applicable to large compression bending members.Compared with the original standard formula,the algorithm proposed in the article has a higher degree of agreement with the finite element simulation results,and can be used for the design of large compression bending components such as super high bridge towers.

关 键 词：斜拉桥 桥塔 稳定性 二阶效应 有限元分析 公式算法 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]