考虑桩土作用的储罐模拟地震振动台试验

Shaking Table Test of a Liquid Storage TankConsidering Pile—Soil Interactions

摘要:

为研究考虑桩土相互作用的储液罐的动力响应及长周期地震波对储液晃动、储罐提离的影响，根据量纲分析法设计了桩-土-储罐模型进行了振动台试验。试验中采用4条基岩波、4条地表波进行振动台试验。试验显示基岩波与地表波输入时，体系变化规律基本一致，其结果表明：土体地表加速度被放大，且输入加速度峰值增加，地表加速度放大倍数减小；一般地震波时，随着输入加速度峰值的增加，储液晃动波高大致呈线性增加。长周期地震波下则为非线性增加，且晃动波较大。此外，液体产生的晃动波高与储罐类型相关。细高型储罐产生的波高稍大；储罐提离高度随着输入加速度峰值的增加呈非线性增长。长周期地震波激励下，储罐提离高度小于一般地震波时的提离高度。细高型储罐在长短周期地震波激励下，提离高度较为接近，而一般储罐在两种地震波激励下，提离高度相差较大。细高型储罐提离高度大于一般储罐的提离高度。建议在储罐设计时考虑长周期地震波的影响。

Abstract:

To study the dynamic response of a liquid storage tank considering pile-soil interactions and the effect of long-period seismic waves on the liquid sloshing and tank uplift, a pile-soil-storage tank model was designed to perform a shaking table test based on dimensional analysis. In the experiment, four bedrock waves and four surface waves were used. The system change laws obtained when bedrock waves and surface waves were used as input were the same. The surface acceleration was amplified, and the magnification factor of surface acceleration decreased with increasing PGA as input. Under the action of general ground motion, increases in PGA input result in approximately linear increases in the shaking wave height of the stored liquid; by comparison, under the action of long-term ground motion, a nonlinear increase is observed, and the shaking wave height of the liquid is large. In addition, the wave height generated by the liquid is related to the tank type. The uplift height of the storage tank increases nonlinearly with increasing PGA input and is less than that under general ground motions under the excitation of long-period ground motions. The influence of long-period seismic waves should be considered in the design of storage tanks.