立式储罐滚动隔震地震模拟振动台试验研究

Earthquake simulated shaking table test of vertical tank with rolling isolation

为了降低强震作用下立式储罐的地震响应,根据机械动力学原理设计了滚动隔震装置,同时,根据相似比理论设计了原型为1 000 m3储罐的1∶4缩尺滚动隔震储罐模型。选取3条位移波作为地震动输入,对滚动隔震储罐模型进行地震模拟振动台试验。试验结果表明:滚动隔震后结构体系的基本周期被拉大,避开了地震动的卓越频率;滚动隔震后沿罐壁高度方向加速度峰值降低明显,减震率最高可达75%;罐壁环向应力在储罐的底部和中上部最大,轴向应力在储罐的底部最大,隔震后均有较大降低,隔震效果明显;不同地震动的隔震效果不同,El Centro波的隔震效果最好,同种地震动作用下随着地震能量的加大,隔震效果降低;滚动隔震不能有效降低晃动波高。建议实际工程应采取控制晃动波高的措施。

To reduce seismic response of the vertical tank under the action of strong earthquake, according to the principle of mechanical dynamics, the rolling isolation device was designed, at the same time, according to the similarity theory, the 1：4 scale rolling isolation tank model that prototype was 1 000 m3 tank was designed. The three displacement waves were selected as the ground motion input, conduct rolling isolation tank model shaking ta- ble test. The experimental results showed that the basic period of the structure system is lengthen after rolling earth- quake isolation; avoid the dominant frequency of the ground motion. The acceleration peak obviously decrease a- long the direction of tank wall height after rolling isolation, decreasing amplitude ratio is up to 75%. The hoop stress of tank wall is the biggest on the bottom and the upper, the axial stress is the biggest on the bottom of the tank, obviously decrease after isolation, isolation effect is obvious. The different ground vibrations have the differ- ent isolation effects, the isolation effect of El Centro wave is the best, with the seismic energy increasing, isolation effect is reduced. Rolling isolation cant effectively reduce the sloshing wave height. Suggest that the measures that control shaking wave height should be taken in the practical engineering.