近断层地震作用下高阻尼橡胶隔震结构的响应分析

Response analysis of high damping rubber isolated structure under near-fault earthquake

近断层地震动因其具有短持时、大幅值和长周期速度脉冲等特点,对建筑结构的破坏作用更加显著。高阻尼橡胶隔震支座作为一种新型的隔震支座,添加了大量高阻尼材料,可以耗散更多的地震能量,在隔震工程中的应用越来越广泛。本文研究高阻尼橡胶隔震结构在近断层地震作用下的响应分析,有着较大的理论和工程应用价值。文章首先探讨了高阻尼橡胶隔震支座的力学性能。然后以实际工程为背景,用SAP2000软件模拟双折线力学模型,建立高阻尼橡胶隔震结构有限元分析模型。通过非线性时程分析,对比近断层与远场地震作用下的基底剪力、楼层位移、楼层加速度等结构响应。结果表明高阻尼橡胶隔震结构在近断层地震作用下的响应比远场地震作用要大。

Owing to the fact that near-fault ground motion is featured with short duration,large amplitude and long-period velocity pulse,it imposes serious damage to buildings. As a new type of isolation bearing,high damping rubber bearing( HDRB) is added with large amount of high damping material,dissipating more seismic energy,so it is widely used in base-isolation engineering. Therefore,it has great theoretical and engineering value to study the dynamic response of HDR isolated structure under the near-fault earthquake.Firstly,the mechanical properties of high damping rubber bearing are discussed. Then,based on the practical engineering,with SAP2000 to simulate the bilinear hysteretic model,the study HDR isolated structure is developed. By the nonlinear time-history analysis method,the structural responses such as base shear,story displacement and story acceleration under near-fault and far-field earthquake are compared. The results show that the seismic response of HDR isolated structure under near-fault earthquake is much larger than that of far-field earthquake.