简支梁桥采用减隔震装置后抗震性能分析

介绍了桥梁隔震的概念。以3座不同柱高的城市高架桥工程为实例,分别采用板式橡胶支座和铅芯橡胶支座隔震装置。研究采用隔震装置的高架桥地震反应计算表明:随着立柱的高度增加,结构的柔性增大,桥梁的抗震性能也越好;采用铅芯橡胶支座后,桥梁地震响应明显降低,桥梁抗震性能显著增强。以上海软土地基为基准刚度,研究了基础弹性刚度对采用铅芯橡胶支座桥梁地震响应的影响。结果表明:当基础弹性刚度小于基准值的5倍时,应考虑基础的弹性影响;当刚度大于基准值的5倍时,其影响甚微。

On Anti-seismic Performance Analysis of Simple Supported Beam Bridge with Seismic Isolation Device

The concept of bridge seismic isolation is introduced in this paper.Taking three urban viaduct bridges projects with different column depth for example,the three bridges are adopting laminated rubber bearing and lead rubber bearing separately.The related earthquake response calculation of viaduct bridges with seismic isolation device can show that,1) with the column height increasing,the flexibility of structure is increased and anti-seismic performance of bridge is better;2) by adopting lead rubber bearing,bridge earthquake response is reduced and anti-seismic performance is strengthened obviously.With Shanghai soft soil foundation as a benchmark stiffness,the influence to bridge(with lead rubber bearing) earthquake response by foundation flexible stiffness is researched.The results can show that,1) when foundation flexible stiffness is less than 5 times of reference value,flexibility influence of foundation shall be considered;2) when the stiffness is more than 5 times of reference value,the influence can be ignored.