高层隔震结构提离摇摆耦合动力理论模型及地震响应分析

针对地震作用下高层隔震结构摇摆倾覆问题，提出考虑隔震层刚心变动的摇摆提离耦合动力理论模型，给出了地震响应提离摇摆的3个界限(即临界提离受拉界限、摇摆界限和倾覆界限)公式。通过大高宽比隔震结构振动台试验，进行不同峰值加速度地震波作用下试验结果分析，得到在地震动峰值加速度0.4g输入工况中，结构在El Centro波下进入提离受拉状态，在Taft波作用下，结构响应较大，提前进入摇摆状态；而在峰值加速度0.6g输入工况中，两条波作用下结构均进入了摇摆界限，尚未进入倾覆状态，隔震层位移未超出GB 50011—2010《建筑抗震设计规范》限值，但此时支座的拉伸应变均已超过10%的安全界限，属于危险状态。对比分析摇摆模型与试验得到加速度及滞回曲线，可知理论模型与试验结果具有较好一致性。最后，采用数值分析方法，研究了提离摇摆耦合动力模型对不同高宽比高层隔震结构地震响应的影响，得到不同地震动峰值对不同高宽比结构的3个临界状态的影响规律，即摇摆提离模型的扭转角与结构高宽比和输入地震动峰值加速度有较大关系，其中地震动峰值加速度的变化影响更为显著。

Seismic response analysis and dynamic theoretical model for high-rise isolated structures considering uplifting and rocking effects

Based on the rocking effect of high-rise isolated structures, this paper proposed a new dynamic theoretical model which considered the variation of stiffness center and the coupling properties of rubber bearings. Besides, three critical states were proposed which were the tension state, the rocking state and the overturning state, respectively. After conducting shaking table tests on an isolation structure with a large aspect ratio, the test results under different peak ground accelerations (PGAs) were analyzed. The results show that the structure reaches the tension state under the El Centro wave when the PGA is 0.4g. The structure reaches the rocking state under the Taft wave when the PGA is 0.4g due to the relatively large response under the Taft wave. When the PGA is 0.6g, the structure reaches the rocking state under both the El Centro and Taft waves. The displacement of the isolation layer does not exceed the specification limit, but at this time the tensile strain of the bearing has exceeded the safety limit of 10%, which was considered risky. The analysis results of the proposed model in this paper and the experiment results are compared which show a great consistency between them. At last, numerical analysis methods are adopted to explore the impact effects caused by different aspect ratios and different PGAs. The results show that the influence of the PGA is more significant. The influence of different PGAs on the three limit states is studied so as to provide estimation of dimensions to high-rise isolated structures.