摘要
运用有限元软件SAP2000,建立不同未隔震桥梁自振周期,铅芯橡胶隔震支座弹性周期、非弹性周期和隔震屈服比的198个单自由度隔震桥梁模型,进行非线性地震能量反应分析,研究铅芯橡胶隔震支座屈服比与其耗能比的关系以及不同地震水平下的优化屈服比。研究表明,隔震支座优化屈服比随着地震动水平的增强而增大,但增大趋势逐渐减缓;以ElCentro波作为激励得到的优化屈服比拟合公式对不同地震波具有较好的适用性;将基于最大限度耗能确定的隔震支座优化屈服比应用到桥梁隔震的两阶段设计中,即保证了桥梁在正常条件下的使用,又保证了在较大地震荷载作用下,隔震支座最大限度地发挥耗能减震作用。
198 single degree of freedom models of the seismically isolated bridges were established in FEA software SAP2000. The seismically isolated bridge models were generated by changing the fundamental period of bridge pier, the elastic and inelastic period as well as the yield ratio of seismically isolated bearing. The nonlinear seismic energy responses of the single degree of freedom models were analyzed. The relationship between the yield ratio of isolated bearing and the energy dissipation ratio was studied. The optimal yield ratios of isolated bearing under different seismic levels were determined. The analysis results show that the yield ratio of seismically isolated bearing is increased with the increasing of the seismic levels, and the increasing trend is gradually smooth. The fitting formula of yield ratios was calculated from the energy response analysis under El Centro earthquake wave, which was well suitable for different types of earthquake waves. The optimal yield ratio of seismically isolated bearing based on the maximum energy dissipation ratio can be used in the two stage bridge seismic isolation design. Then the isolated bearing keeps elastic under the normal working conditions, and the energy dissipation efficiency of the bearing can be displayed effectively under intensive seismic motions.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2010年第2期34-39,共6页
China Railway Science
基金
铁道部科技研究开发计划项目(2008G010-A
2008G028-C)
关键词
桥梁
铅芯橡胶支座
隔震
屈服比
参数优化
地震能量反应
Bridge
Lead rubber bearing
Seismic isolation
Yield ratio
Parameter optimization
Seismic energy response
