大跨曲线矮塔斜拉桥主梁锚固区蝶形应力区及优化配筋研究  

Butterfly⁃shape Stress Region and Its Rebar Optimization in Anchorage Zone of Main Girder of Large⁃span Curved Extradosed Cable⁃stayed Bridge

作　　者：朱良 黄博 李佳文 王江波[2] 朱厚达 熊治华 ZHU Liang;HUANG Bo;LI Jiawen;WANG Jiangbo;ZHU Houda;XIONG Zhihua(Shaanxi Company of China Railway Construction Investment Group Co.,Ltd.,Xi’an,Shaanxi710000,China;CCCC First Highway Consultants Co.,Ltd.,Xi’an,Shaanxi710068,China;College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling,Shaanxi712100,China)

机构地区：[1]中国铁建投资集团有限公司陕西公司,陕西西安710000 [2]中交第一公路勘察设计研究院有限公司,陕西西安710068 [3]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《施工技术（中英文）》2024年第12期58-63,87,共7页Construction Technology

基　　金：陕西省交通运输厅2020年度交通科研项目(20-40k)。

摘　　要：为了探究曲线矮塔斜拉桥主梁局部锚固区受弯扭耦合效应的影响,优化局部配筋方案,以王家河大桥为工程背景,从应力、变形及预应力施加效率3个层面,对成桥和最大悬臂工况下直桥和弯桥局部节段模型开展对比计算,提出弯扭耦合效应造成的锚固区蝶形剪应力集中区域。结果表明:弯扭耦合效应增大了锚固区主梁各构件的主拉应力;同时,增大蝶形剪应力集中区域的面积约40%,在该区域可采用非对称配筋方案,适当增加锚固处弯曲侧抗剪钢筋比例;弯扭耦合效应会使主梁锚固区横向位移明显增大,增幅接近30%,但对挠度无显著影响;弯扭耦合效应下主梁锚固区预应力施加效率小幅度提升,在配束计算时应予以考虑。In order to explore the influence of bending torsion coupling effect on the local anchorage zone of the main girder of the curved low tower cable⁃stayed bridge,and optimize the local reinforcement scheme,taking Wangjiahe Bridge as the background,the segmental models of straight bridge and curved bridge were calculated and compared in terms of stress,deformation and prestress efficiency under completed and the maximum cantilever construction conditions.The butterfly⁃shaped shear stress concentration region of the anchoring zone caused by flexural⁃torsion coupled effect was proposed.The results show that the flexural⁃torsion coupled effect increases the principal tensile stress of each part of the main girder in the anchoring area.Meanwhile,the flexural⁃torsion coupling significantly increases the area of butterfly⁃shape shear stress concentration region by nearly 40%.The asymmetric reinforcement scheme can be adopted,and the proportion of shear reinforcement on the bending side of the curved bridge anchorage should be increased appropriately.The flexural⁃torsion coupled effect remarkably increases the transverse displacement of the anchoring part of the main girder by near 30%.Conversely,it has little effect on the deflection of bridge.The efficiency of prestressed application in the anchorage zone of the main girder is slightly improved under the coupling effect of bending and torsion,which should be taken into account in the calculation of beam configuration.

关 键 词：桥梁工程 矮塔斜拉桥 曲线桥 锚固区 剪应力 优化配筋 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]