附设间隙阻尼减震装置的高位隔震连体结构振动台试验研究

Shaking table test of high-level isolation connected structure with gap damper device

针对高位隔震连体结构,提出附设间隙阻尼装置控制罕遇地震下连廊隔震支座位移。通过设计高宽比为6的双塔连体结构试验模型,对连廊与塔楼顶部仅采用隔震连接以及隔震与间隙阻尼装置连接的两类结构体系进行模拟地震振动台试验研究。选取远场El Centro波和速度脉冲效应明显的近场Chi-Chi波、Kobe波作为地震激励。通过测量隔震支座水平位移、间隙阻尼装置力与位移响应、连廊结构加速度响应以及塔楼结构加速度和位移响应,分析罕遇地震与极罕遇地震作用下间隙阻尼装置对隔震支座位移的控制效果,以及对连廊结构和下部塔楼结构抗震性能的影响。结果表明:间隙阻尼装置可以有效地控制罕遇和极罕遇地震作用下隔震支座位移,8度罕遇地震作用下,隔震支座最大位移减小59.61%;间隙阻尼装置传导轴与限位环产生剧烈冲击,引起高频振动能量进入连廊结构,导致连廊水平向加速度响应有所放大,而竖向加速度响应显著;远场地震作用下,间隙阻尼装置的启动对塔楼结构楼层加速度和层间位移角有所放大,但未造成不利影响;在速度脉冲周期与整体结构基本自振周期接近的近场地震作用下,当地震波峰值加速度为0.40g时,附设间隙阻尼装置使塔楼结构楼层峰值加速度和峰值层间位移角分别减小24.09%和31.7%,对塔楼结构具有一定减震控制作用。

A gap damper device was proposed to control the displacement of isolation bearing of the corridor when a high-level isolation connected structure was subjected to rare earthquakes.A twin tower connected model structure with an aspect ratio of 6 was firstly designed.The corridor and tower were connected by the isolation only and by the combination of the isolation and gap damper device,respectively.The two structural systems were tested by a series of shaking table tests.The far-field El Centro wave and pulse-like near-field Chi-Chi and Kobe waves were selected as seismic excitations.The horizontal displacement of the isolation bearing,the force and displacement responses of the gap damper device,the acceleration response of the corridor,and the acceleration and displacement responses of the tower structure were measured.The control effect of the gap damper device on the displacement of isolation bearing under rare and extremely rare earthquakes,as well as the influence of the gap damper device on the corridor and tower structure were analyzed.The results show that the gap damper device can effectively control the isolation bearing displacement under rare and extremely rare earthquakes.Under the rare earthquakes with intensity 8,the maximum displacement of the isolation bearing can be reduced by up to 59.61%.The gap damping device generates a severe impact between the transmission shaft and limit ring,inducing high-frequency vibration energy into the corridor structure.The horizontal acceleration responses of the corridor are amplified,and the vertical acceleration responses are more serious.Under the far-field earthquakes,the activation of the gap damping device increases the floor acceleration response and inter-story drift of the tower structures to some extent,but it do not cause adverse effects on the tower structures.Under the near-field earthquakes,where the velocity pulse period is close to the fundamental natural period of the overall structure,the gap damping device provides some seismic control effects on the tower structures.When the peak ground acceleration of the ground motion is 0.40g,the peak acceleration and peak inter-story drift of the tower structure are reduced by 24.09% and 31.7%,respectively.