拱肋局部特性改变对拱桥动力特性影响试验研究  

Experimental study of effect of local variation of arch rib on dynamic property of arch bridge

作　　者：范颖芳[1] 周晶[1] 朱彤[1] 张学志[2] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]吉林省公路管理局,吉林长春130021

出　　处：《大连理工大学学报》2009年第3期401-407,共7页Journal of Dalian University of Technology

基　　金：国家自然科学基金资助项目(50708010);吉林省公路交通厅资助项目(2002-1-06);辽宁省博士启动基金资助项目(1050259)

摘　　要：针对一座服役40余年的钢筋混凝土旧拱桥进行了全面的现场检测(包括材料性能和拱桥静、动力特性).基于模型相似理论,以20∶1的几何比尺制作了单跨拱桥有机玻璃模型.为了不损坏结构的完整性,尝试利用对主拱圈局部增加质量块来模拟拱肋局部特性的变化.以大桥的动力特性作为大桥"健康"状况的指纹,对拱肋不同位置局部质量变化后的模型结构进行动力模型试验,得到了结构阻尼、固有频率和振型.研究表明,拱肋局部特性的变化对结构加速度放大倍数影响显著,而对模型自振频率和阻尼的影响并不明显.Field tests （inclusive of material property, static and dynamic structural properties） were conducted on a reinforced concrete arch bridge, which has been in service for more than 40 years. Based on the similarity theory of model design, a scaled model of one-span bridge was fabricated by organic-glasses, and the scale factor of geometry is 20. To keep the structural integrity, added mass were added on different locations of the arch ribs to change the structural dynamic properties. Taking structural dynamic properties as damage fingerprint, dynamic tests were performed respectively. Dynamic responses （structural damping, frequency, mode shape, etc. ） of the damaged bridge models are achieved. It is shown that local variation of arch rib makes a great influence on the acceleration amplification along arch ribs, while it has a little effect on the structural natural frequency and damping ratio.

关 键 词：拱桥 健康检测 有限元分析 模型试验 动力特性 

分 类 号：U446.1[建筑科学—桥梁与隧道工程]