近断层激励下子结构组合隔震的巨-子结构试验

为解决受限于隔震支座的抗拉能力和结构高宽比限值、隔震技术很少应用在超高层建筑的问题，在新型巨-子结构体系的子结构底部设置由铅芯橡胶隔震支座和弹性滑移支座组成的组合隔震层，设计制作了一个有3个巨型结构层的巨-子结构模型，对其进行了近断层地震动及远场地震动作用下的振动台试验，研究了组合隔震层对主结构和子结构振动的减震效果和近场地震对其影响.研究结果表明,子结构底部设置组合隔震层，对主结构来说相当于调谐质量阻尼器，其对主结构的地震响应具有较好的调谐减震作用；对子结构来说相当于基底隔震，其对子结构的地震响应具有显著的隔震效果.由于脉冲效应，近断层地震动作用下主结构和子结构的地震响应都要大于相同场地的远场地震动.
To solve the problem of seldom use of isolation technology in super high-rise buildings as well as the restriction on the tensile capacity of isolation bearing and structural height-width ratio limitation，in this paper，the combined isolation layers consisting of lead rubber bearings and elastic sliding bearings were set at the bottom of the sub-structures in the new mega-sub structure system. An experimental model of mega-sub structure was designed and manufactured，which included three mega floors. Shaking table tests of the uncontrolled and controlled mega-sub structure under near-fault and far-fault ground motions were carried out. Vibration control effects of combined isolation layers on the seismic vibrations of main-structure and sub-structures and the influences of near-fault ground motions were studied. The results show that the combined isolation layer at the bottom of sub-structure is equivalent to a tuned mass damper for the main-structure，and it has obvious damping effect of TMD on the seismic reactions of main structure，while it is equal to a base isolation structure for the sub-structure itself，and it has significant isolation effect on the seismic responses of sub-structure. Seismic reactions of the main-structure and the sub-structures under near-fault ground motions are larger than that under far-fault ground motions due to the pulse effect.