超大跨劲性骨架拱桥缩尺模型试验方案设计研究  

Design of Scaled-Down Model Test of Very Long Rigid Skeleton Arch Bridge

作　　者：周建庭[1] 范永辉 罗超[1] 辛景舟 杨俊[1,2] ZHOU Jianting;FAN Yonghui;LUO Chao;XIN Jingzhou;YANG Jun(State Key Laboratory of Mountain Bridge and Tunnel Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Guangxi Communications Investment Group Co.,Ltd.,Guangxi 530022,China)

机构地区：[1]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074 [2]广西交通投资集团有限公司,广西南宁530022

出　　处：《桥梁建设》2024年第3期24-30,共7页Bridge Construction

基　　金：广西重点研发计划项目(桂科AB22036007);重庆市技术创新与应用发展专项重点项目(CSTB2022TIAD-KPX0205);重庆市杰出青年科学基金项目(CSTB2023NSCQ-JQX0029)~~。

摘　　要：为对超大跨劲性骨架拱桥缩尺模型试验方案进行合理设计,以计算跨径600 m的劲性骨架拱桥——天峨龙滩特大桥为背景,围绕模型缩尺比、结构设计、材料及加载系统等关键环节,开展主拱圈缩尺模型试验方案设计研究。最终确定模型拱缩尺比为1∶10,劲性钢骨架采用单肋形式,采用与实桥主拱圈性能相近、便于施工的材料,采用阵列式滑轮组加载系统实现模型拱和实桥主拱圈的应力等效,还原外包混凝土分环分段浇筑施工,并简化劲性钢骨架与管内混凝土施工。将模型拱外包混凝土应力实测值、ANSYS建模计算得到的模型拱理论值及实桥主拱圈理论值进行对比,结果表明:模型拱和实桥主拱圈外包混凝土在施工阶段的应力变化趋势基本相同,最大绝对误差在2 MPa以内,模型拱应力实测值和理论值也吻合较好,缩尺模型试验方案设计合理。The Tian′e Longtan Bridge,with the arch spanning 600 m,is used as a case to study the rational design of the scaled-down model test of the very long rigid skeleton arch bridge,and the study focuses on multiple critical issues,including the scale ratio of the model,structural design,material selection and loading system.It was determined to take a scale ratio of 1∶10 in the fabrication of the model,choose a single rigid steel skeleton arch,utilize the materials with properties the same as those of the real bridge and easy to be implemented.Furthermore,the loading system with arrayed pulleys were employed to achieve the stress equivalence of the model and the real arches,and replicate the segmented-ring casting of the encasement concrete,and simplify the construction of the rigid skeleton and infilling concrete.The measured stresses in the encasement concrete of the model arch,theoretical stresses obtained by numerical simulation in ANSYS were compared with the theoretical values of the arch of the real bridge.It is shown that the encasement concrete of model arch and the arch of the real bridge exhibit roughly the same stress variation trend,with a maximum absolute difference of 2 MPa,the measured and theoretical values of the model arch agree well,indicating that the proposed scaled-down model test design is rational.

关 键 词：拱桥 劲性骨架 主拱圈 缩尺模型 缩尺比 应力等效 试验方案设计 有限元法 

分 类 号：U448.22[建筑科学—桥梁与隧道工程]