带抗拉装置高层隔震结构振动台试验研究

西昌（9度区）某高层基础隔震结构，其上部为框架-核心筒结构，总高度为58.3m（不计入隔震层），隔震层采用铅芯橡胶隔震支座。为研究该隔震结构的抗震性能及检验带抗拉装置隔震支座的有效性，进行了缩尺比为1/15模型的模拟地震振动台试验。结果表明，隔震层降低了上部结构的加速度反应，隔震层上加速度放大系数小于0.5，可满足抗震设防烈度降低一度的设计目标；隔震结构的位移集中在隔震层，上部结构的层间位移较小，层间位移角满足规范层间位移角限值要求；隔震层力-位移滞回曲线较为饱满，具有良好的耗能能力。罕遇地震作用下，支座出现拉应力，说明隔震结构在高烈度地震作用下存在倾覆的可能性。对角部隔震支座加装抗拉装置后，再次进行振动台试验，结果表明，抗拉装置不会对结构水平向动力特性及支座在正常受压状态下的竖向运动和水平向运动产生显著影响，通过对比证明了其在隔震支座受拉情况下提供的有效抗拉作用。

Shaking table test on high-rise isolated building with tension-resistant devices

A high-rise base isolated building in Xichang (seismic intensity of 9) is taken as prototype. The upper-structure employs frame-core tube form with a total height of 58.3m using lead rubber bearings as isolators. Shaking table test on a model structure with a similitude ratio of 1/15 was conducted to investigate the performance of the isolated structure under earthquake. Results illustrate that the isolation floor reduces acceleration response of upper-structure remarkably, and the amplification coefficient of the isolation layer is smaller than 0.5 which meets the requirement of decreasing one degree of seismic intensity for structural design. Horizontal displacement concentrates on isolation layer, thus story displacement is comparatively smaller and inter-story drift meets the limitation requirement in Chinese code. Besides, the full hysteretic loops of isolation layer indicate good ductility and energy dissipation property. However, under strong earthquake, tensile stress occurs in the bearings, which reveals the risk of overturning. After installation of tension-resistant device for bearings in the corner,the following experiment results reveal that this device would not pose significant effect on the horizontal mechanic properties of the structure and the regular vertical and horizontal motion of the bearing under compression state. And the tension resistant effect of the device when the bearing is under tensile state is proved by comparison results.