大跨飘浮体系斜拉桥减震控制研究

以一座大跨斜拉桥为实例,建立其有限元模型计算分析了主动控制、半主动控制和被动控制对飘浮体系斜拉桥的减震效果,并分析了地震行波效应对斜拉桥地震反应的影响。结果表明,不同频谱成分的地震动输入显著影响三种控制方法的减震效果;半主动控制对于该斜拉桥整体地震反应的控制效果优于始终提供最大阻尼力的被动控制;行波效应对该斜拉桥无控制和有控制地震反应的影响基本相同,并且行波效应对三种控制方法减震效果的不利影响很小。这为漂浮体系斜拉桥的减震控制提供了理论上的指导。

STUDY ON SEISMIC RESPONSE CONTROL FOR A LONG-SPAN FLOATING CABLE-STAYED BRIDGE

Vibration-suppressing effectiveness of active control, semi-active control and passive control for a long-span floating cable-stayed bridge is calculated and analyzed with its finite element model. Effect of seismic traveling wave on the seismic responses of the cable-stayed bridge is also analyzed. The results indicate that ground motion inputs with various frequency components evidently influence the vibration-suppressing effectiveness of the three control methods. Semi-active control is better than passive control always providing the max damping force for the control effectiveness of the whole seismic response. Influence of seismic traveling wave on the uncontrolled seismic response of the bridge is almost the same as that on the controlled seismic response. Traveling wave can make bad influence on the beam of the bridge, but it is beneficial to the bridge tower. Its bad influence on the three control methods is little. This study provides theoretic guide to vibration control for floating cable-stayed bridges.