摘要
通过研究双质点模型自由振动特性发现,当质量比与刚度比在某一特定范围内时,二阶振型的贡献度远小于一阶振型的。因此,隔震悬挂结构可由双质点模型等效简化为单质点模型进行计算分析。数值计算对比分析结果表明:由等效单质点模型计算的体系基本自振频率与双质点模型的一阶频率非常接近,最多相差0.3%左右;两种模型计算的被悬挂结构相对于支撑结构的地震反应位移和速度时程曲线吻合情况均较好,并显示出了一致的周期特征。虽然在个别峰值处存在微小偏差,但可满足工程需要。因此,单质点等效动力模型可以作为一种行之有效的方法完成隔震悬挂结构的动力简化计算。
The analysis of free vibration characteristics of double mass model shows that the contribution of the second mode is much less than the first one when both mass and stiffness ratio are in a certain range.For this reason,the computational analysis of isolated suspension structure can be carried out with equivalent single mass model as effective as double mass model.Numerical calculation and comparative analysis show that the fundamental frequency of equivalent single mass model is close to the first order natural frequency of double mass model,and the frequency deviation is around 0.3% at most.When the two models excited by the same seismic ground motion,the displacement time-history responses of suspended structure relative to supporting structure coincide closely.The relative velocity time-history responses and the eigenperiod also coinside closely.Although there are minimal deviations at a few peaks,the results could satisfy the demand of control.Consequently,the dynamic simplified calculation of isolated suspension structure can be carried out with equivalent single mass model.
出处
《地震工程与工程振动》
CSCD
北大核心
2011年第2期118-123,共6页
Earthquake Engineering and Engineering Dynamics
基金
安徽工业大学青年教师科研基金项目(QZ201007)
关键词
隔震悬挂结构
等效动力模型
等效原则
简化计算
地震反应
isolated suspension structure
equivalent dynamic model
principle of equivalence
simplified calculation
seismic response
