地震模拟振动台基础动力反应的比较研究

A Comparative Study on Dynamic Response of Seismic Shaking Table Foundation

针对某一拟建的6 m×8 m三向六自由度地震模拟振动台基础,应用《动力机器基础设计规范》方法、拉普拉斯变换法和动力阻抗法,分别计算其动力响应,经计算结果对比发现:由于各方法采用的基本参数的求取方法不同,计算得到的加速度响应在低频区和中频区存在一定的差异,但在高频区趋向一致。通过参数分析,建议振动台基础设计分析可根据规范确定地基刚度,参照Lysmer比拟法计算阻尼。

For a 6 m × 8 m three-way six-DOF seismic shaking table foundation, three methods such as the method carried in Code for Dynamic Machine Foundation Design, the Laplace-Transform method and dy- namic impedance method are applied respectively to calculate its dynamic response. A comparison of the re- suits shows that the acceleration responses obtained with different methods are coincident in higher frequency while divergent in lower and intermediate frequency ranges. It is suggested on the basis of parameter analysis that the groundsill stiffness be calculated according to the Code and the damping computed against the Lys- mer analogue method when the design of seismic shaking table foundation is analyzed.