Field Load Testing of Inclined Tower Cable-stayed Bridge without Back-stays

无背索斜塔斜拉桥荷载试验
刘永健1,2，杨 健1，梁 鹏1，颜东煌2，许红胜2
（1.长安大学 桥梁与隧道陕西省重点实验室，陕西 西安 710064；
2.长沙理工大学桥梁与结构工程学院，湖南 长沙 410076 ）
摘 要：为了探讨和验证无背索斜塔斜拉桥的设计理论和实际工作性能，对长沙洪山桥进行了静动力荷载试验，并结合三维有限元模型的理论计算，对比分析了试验荷载工况下该桥位移、应力和索力的变化规律以及模态频率、阻尼比和冲击系数等结构动力特性，探讨了13m长悬臂钢-混凝土组合梁结构的扭转性能。结果表明：桥梁结构动静力实测值与理论值吻合良好，桥梁整体工作性能好；扭转工况下，组合梁端部上下游位移差较大，抗扭刚度相对较低；结构前两阶阻尼比较大，对振动有较好的衰减作用。荷载试验验证了分析理论的正确性和施工技术的可靠性，可供同类桥梁的设计提供参考。
关键词：桥梁工程；荷载试验；无背索斜塔斜拉桥；钢-混凝土组合梁
中图分类号：U448.27 文献标识码：A

Field Load Testing of Inclined Tower Cable-stayed Bridge without Back-stays
LIU Yong-jian1,2，YANG Jian1，LIANG Peng1，YAN Dong-huang2，XU Hong-sheng2
（1. Key Laboratory for Bridge and Tunnel of Shaanxi Province, Chang’an University, Xi’an 710064, Shaanxi, China 2. School of Bridge & Structure Engineering, Changsha University of Science & Technology）

Abstract：This paper presents a field loading test and analytical modeling for the inclined tower cable-stayed bridge without back-stays, Hongshan bridge. The object of the study is to evaluate the design theory and structural behavior of the bridge. Test results were compared with the calculating results of 3D finite element model, including the static behavior—the stress and deformation of the girder and bridge tower, cable forces，and the dynamic behavior—the structural frequency, damping ratio and impact coefficient. Moreover, torsional properties of the box girder with 13-meter-long steel-concrete composite cantilevers were analyzed. The results showed that the measured values agreed well with the calculating ones, while in the twisting working condition the deformation of two sides of the box girder had much difference, which meant the relatively lower torsional stiffness. On the other hand, the measured damping ratio of the bridge, whose girder had long steel-concrete composite cantilevers, was larger than others, which meant a better anti-vibration performance. The results mentioned above verify the design theory and construction method, and also provide reference for the design of the same type bridge.
Key words：bridge engineering; field loading test; inclined tower cable-stayed bridges without back-stays; steel-concrete composite girder

[ 本帖最后由 yangjian3579 于 2009-12-26 18:49 编辑 ]