摘要
以嘉绍大桥6塔斜拉桥为研究对象,详细分析了刚性铰以及塔梁纵向约束形式对6塔斜拉桥动力特性和地震反应的影响特点。分析结果表明:(1)刚性铰的设置对多塔斜拉桥主梁的1阶对称侧弯振型频率和1阶对称扭转振型形状影响较大,但对于多塔斜拉桥地震反应影响很小;(2)塔梁纵向约束形式主要改变多塔斜拉桥主梁的竖弯和侧弯刚度,随着纵向约束增强,主梁竖弯和侧弯振动频率增加,并且部分振型形状发生明显改变;(3)全漂浮体系的位移反应过大,而全固结体系的内力反应过大;(4)部分约束体系的位移反应很小,边塔和中塔的内力反应亦较小,而次边塔的内力反应则过大。因此,刚性铰的设置对多塔斜拉桥抗震性能影响很小,而塔梁纵向约束形式则对其抗震性能产生重要影响。
The influences of rigid hinge and longitudinal constraint forms between pylon and girder on the dynamic property and seismic response of multi-pylon cable-stayed bridge are analysed with regard to the Jiaxing - Shaoxing Bridge, a 6-pylon cable-stayed bridge. The result shows that （ 1 ） the installation of rigid hinge has significant effect on the of the first-order symmetric lateral bending modal frequency and the first- order symmetric torsional mode shape of bridge girder, while the installation of rigid hinge has a limited effect on the seismic response of multi-pylon cable-stayed bridge; （2） the longitudinal constraints between the bridge pylon and girder mainly change the vertical bending stiffness and lateral bending stiffness of the main girder, with the increase of the longitudinal constraints, the vertical bending and lateral bending modal frequency of bridge girder are increased and some of the vibration mode shape are significantly changed ; （3） the displacement responses of fully floated system and the internal force responses of fully constrained system are too large; （4） with regard to the partial constrained system, the displacement responses are small and the internal forces of side pylons and middle pylons are also small, while the internal forces of secondary side pylons are too large. Therefore, the installation of rigid hinge has little effect on the seismic performance of the bridge and the longitudinal constraints between pylon and girder will significantly affect the seismic performance of the bridge.
出处
《公路交通科技》
CAS
CSCD
北大核心
2014年第7期65-71,共7页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金项目(51178100)
国家科技支撑计划项目(2014BAG07B01)
交通运输部"十二五"重大科技专项项目(2011318223170)
关键词
桥梁工程
多塔斜拉桥
有限元法
结构体系
地震反应
动力特性
刚性铰
纵向约束
bridge engineering
multi-pylon cable-stayed bridge
finite element method
structural system
seismic response
dynamic property
rigid hinge
longitudinal constraint
