15×10~4m^3立式储罐隔震设计分析

Design and analysis of seismic isolation for 15×10~4 m^3 vertical storage tank

为了研究15×104m3立式储罐隔震设计影响因素,采用有限元数值仿真技术,分析了隔震刚度、浮顶质量、储液密度、罐壁厚度、罐壁的材料弹性模量、储液高度与罐半径比值对储罐的晃动频率和液固耦合频率的影响并与时程分析对照。结果表明:储罐液固耦合振动频率对隔震刚度敏感,隔震刚度较低时,液固耦合刚度的下降,使基底剪力变小;隔震刚度对储罐的液体晃动频率的影响不大,在一定的隔震周期范围内,波高无放大效应;隔震设计时,浮顶的影响可忽略;储液高度与储罐半径比对储罐的液固耦合频率和晃动频率影响较大,隔震设计时存在优化段;储液密度、罐壁厚度、材料弹性模量,隔震设计时可不考虑其影响,进行地震动台实验时,可考虑用其他材料代替钢材,不影响分析结果。

In order to study the factors of seismic isolation design for 15×104 m3 vertical storage tank,the finite element numerical simulation is used to analyze the effects of isolation stiffness,floating roof quality,reservoir fluid density,tank wall thickness,tank wall material elastic modulus,and liquid storage tank height to radius ratio of the tanks on sloshing frequency and liquid-solid coupling ffrequency.Comparison with the time-history analysis results show that： the liquid-solid coupling vibration frequency is sensitive to isolation stiffness.When the isolation stiffness is lower,the liquid-solid coupling stiffness declines and the base shear force becomes small.Isolation stiffness of the tanks hardly affects the frequency of liquid sloshing.In a certain range of the isolation period,the wave height has no amplification effect.In isolation design,the effects of the floating roof can be neglected.The ratio of the storage tank liquid height to the radius of the tank greatly affects the frequency of the liquid-solid coupling and the shaking frequency.The isolation has the design optimization segmentally.The effects of reservoir fluid density,tank wall thickness,material elastic modulus can be neglected.For shaking table test,other materials may be considered to replace the steel and the analysis results do not be affected.