摘要
使用铅芯橡胶支座(LRB)作为隔震设备,分析了一个典型3跨连续梁桥在4种地震作用下的系统响应。采用Bouc-Wen模型模拟LRB的力变形非线性行为,使用有限单元方法建立系统刚度矩阵、质量矩阵和阻尼矩阵,使用龙格库塔法求解非线性方程。研究的重要参数包括桥墩的刚度、支座的屈服强度及屈服后周期,评价的主要依据是主梁振动加速度、桥墩支座位移、桥台支座位移及桥墩底部剪力和弯矩。结果表明:桥墩刚度对地震响应的隔震效果有很大的影响,随着桥墩刚度的减小,隔震效果降低,而LRB对桥墩刚度较大的桥梁有很好的隔震效果;LRB的屈服强度和屈服后周期均对隔震效果有一定的影响,不同的地震激励对系统的影响不同,对某种地震激励,存在一个最优的LRB屈服强度。
The nonlinear response of a typical three span continuous bridge subjected to four earthquake data is analyzed using Lead Rubber Bearings （LRB） to isolate the superstructure from the substructure. The Bouc-Wen model is adopted to simulate the nonlinear hysteric characteristics of force-displacement relationship for LRB. The system property matrix are obtained by using the FEM method, and the Runge-Kutta iterative strategy is used to solve the nonlinear governing equations of motion. This research focuses on assessing the effects of isolation bearings by comparing the seismic response of isolated bridges with the response of corresponding non-isolated bridges through the peak response of the bridges. The important parameters include pier stiffness, yield strength of the LRB, and isolation time period of the LRB. The main evaluating parameters included the superstructure acceleration, bearings displacement at the pier location, and bearings displacement at abutment location. The results show that LRB has significant effectiveness when the pier is very stiff, however, the isolation effectiveness decrease with the pier become more flexibility. Both of the yield strength and the isolation period of the LRB will affect the isolation effectiveness. There is an optimum yield force for the LRB for a bridge subjected to certain seismic excitation. 4 tabs, 5 figs, 9 refs.
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2006年第1期54-58,共5页
Journal of Chang’an University(Natural Science Edition)
基金
江西省自然科学基金项目(550012)
江西省教育厅科研专项基金项目(2005-125)
日本九州工业大学75周年国外合作者研究基金资助项目
关键词
桥梁工程
桥墩
铅芯橡胶支座
隔震
地震响应
bridge engineering
pier
lead rubber bearing
isolation seismic
seismic response
