大墩高差多跨简支钢箱梁桥顺桥向抗震性能研究和抗震韧性提升策略

Study on Seismic Performance along Bridge and Seismic Resilience Upgrading Strategy of Large-pier Height-difference Multi-span Simple-supported Steel Box Girder Bridge

摘要:

以既有工程项目为依托，为提高简支钢箱梁桥在高烈度山区桥梁中应用的安全性，研究桥墩高差对简支钢结构桥梁的纵向地震响应影响规律。首先明确研究案例，选择10跨标准跨径为36 m左右的简支钢箱梁为研究对象；然后通过调整模型中墩高参数、支座参数，对比墩高差对普通约束体系桥梁和采用减隔震约束体系的桥梁在纵向地震作用下的结构响应影响规律；得到桥梁动力特性和纵向地震响应随墩高差的变化规律。同时还提出多跨简支钢梁桥的抗震韧性提升策略，为今后同类桥梁抗震设计提供一定的借鉴作用。

Abstract:

Based on the existing engineering projects, in order to improve the safety in the application of simple-supported steel box girder bridges in high-seismic mountainous areas, the influence of pier height difference on the longitudinal seismic response of simple-supported steel structure bridge is studied. The study case is clarified by selecting a 10-span simple-support steel box girder with the standard span of about 36m as the research object, and then by adjusting the pier height parameter and the support parameter in the model, the effect of pier height difference on the structural response of bridges with ordinary constraint system and bridges with vibration isolation constraint system under longitudinal seismic action is compared. Finally, the change law of the dynamic characteristics and longitudinal seismic response of the bridges with the pier height difference is obtained. In addition, the strategies for upgrading the seismic toughness of multi-span simple-supported steel girder bridges are proposed, which provides some reference for future design of similar bridges.