结构半主动变阻尼控制性能评估

研究了地震激励下结构半主动变阻尼控制的有效性。作为半主动控制系统的经典范例之一,变阻尼控制系统已经在结构控制领域得到了广泛的应用,但是近来的研究显示变阻尼控制对于抑制柔性结构的地震反应是适宜的,而对于刚性结构则是不适宜的。通过谐波分析研究了地震激励下结构振动控制的问题。计算结果显示,变阻尼控制成立的条件与结构频率并无必然联系,而是取决于结构频率与外部激励频率的比值,即就是变阻尼控制的可行性与地面运动的频谱特性是相关联的。此外,也将变阻尼控制的效果与对应的被动上限阻尼控制效果进行了对比。结果显示,在大多数情况下变阻尼控制并不能进一步提高控制效果。

PERFORMANCE EVALUATION OF SEMIACTIVE STRUCTURAL CONTROL USING VARIABLE DAMPERS

The authors study effectiveness of using a semiactive variable damper to control seismically excited structures. As one of classical examples of semiactive control system, variable dampers are widely used for structural control. However, recent studies show variable dampers are effective in reducing seismic responses of flexible structures while it can be used to control responses of rigid structures. Performance of variable dampers for vibration control of structures under seismic excitations is investigated using harmonic wave analysis. The results show that the performance of variable dampers in reducing seismic response of structures depends on the ratio of the disturbance frequencies to the natural frequencies of structures, rather than the natural frequencies of structures only. Therefore, the effectiveness of variable dampers is associated with the characteristics of the ground motion that excites structures. In addition, the control performance of a variable damper is compared with that of a passive damper. It is found that in most cases variable dampers are not more effective than passive dampers.