不同约束方式对匝道桥动力特性的影响研究  

Study on Influence of the Dynamic Characteristics of Ramp Bridge Setting Different Constrainting Forms

作　　者：王克海[1] 张盼盼 吴刚[1] 鲁冠亚 Wang Kehai;Zhang Panpan;Wu Gang;Lu Guanya(Research Institute of Highway,Ministry of Transport of the People's Republic of China,Beijing 100088,China)

机构地区：[1]交通运输部公路科学研究院,北京100088

出　　处：《震灾防御技术》2018年第4期756-763,共8页Technology for Earthquake Disaster Prevention

基　　金：科技部国际科技合作项目(2009DFA82480);交通运输部西部交通建设科技项目(2009318223094);交通运输部公路工程行业标准项目(JTG-C-201012);中央级公益性科研院所基本科研业务费(2016-9018);河北省交通科技资助项目(y-2014031;y-2014032)

摘　　要：近年来,地震作用下的匝道桥表现出较高的地震易损性。为建立匝道桥的有效约束方式,以减小其地震损伤,本文基于汶川地震中连续梁桥约束方式的调研结果,建立了4种不同匝道桥支座约束方式,并以石家庄石环线某匝道桥为例,对比分析了不同约束方式下匝道桥的自振特性及地震响应。结果表明:板式橡胶支座具有一定的剪切变形能力,可降低桥墩与支座组成的体系刚度,有效分散了上部结构的地震惯性力,保护了下部结构,但应注意其引起的较大主梁位移;固定支座或墩梁固结形式会放大桥墩受力,增加下部结构的损坏,不宜设置在高度较矮、刚度较大的桥墩上;双层挡块和垫石凹槽分级限位支座具有较好的限位能力,并可耗散部分地震能量。In recent years, it has been shown that the ramp bridge has relatively high seismic vulnerability under earthquake. In order to reduce the seismic damage, effective constrainting forms of the ramp bridge should be established. Based on the investigation results of the constrainting forms supported on the continuous girder bridges in the Wenchuan earthquake, 4 different constrainting forms supported on the ramp bridges are established. Taking a ramp bridge in Shijiazhuang as an example, we compare the vibration characteristics and the seismic response of the ramp bridge with different constrains. The results show that the elastomeric pad bearings have a certain shear deformation ability, which could reduce the stiffness of the system of the piers and the bearings. Using these bearings, the seismic force of the upper structure could be effectively distributed which could protect the lower structure, but engineers should also pay attention to the larger beam displacements. Fixed bearings or piers beam consolidation form setting on the bridges will enlarge the pier internal force and increase the damage probability of the lower structure. So it is not suitable to set them on the short piers with higher stiffness. The proposed seismic double-layer stopper and grading limit bearing in this paper have good limiting ability and can dissipate the seismic energy.

关 键 词：桥梁工程 约束方式 匝道桥 动力特性 抗震性能 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]