简支箱梁桥地震反应半主动控制分析

为提高某简支梁桥的抗震能力,采取适当的减震控制措施能够有效地减小桥梁的地震反应。建立了某简支箱梁桥的有限元模型,将板式橡胶支座与磁流变阻尼器组合使用,在桥梁的支座和伸缩缝处共设置8组磁流变阻尼器,分析了不同地震动输入下的简支箱梁桥主动控制、半主动控制和被动控制的减震效果。结果表明,半主动控制对简支梁桥的减震效果非常显著,并且能够很好地接近主动控制的减震效果。半主动控制对于桥梁整体地震反应的减震效果优于始终提供最大阻尼力的被动控制。这为半主动控制阻尼器在简支梁桥抗震中的实际应用提供了理论上的指导。

Analysis of Seismic Response Semi-active Control for Simply Supported Box Beam Bridge

Simply supported beam bridge is widely used in practical engineering and its seismic disaster is serious in recent earthquakes.To enhance the aseismatic ability of simply supported beam bridge is an important content of earthquake prevention and disaster reduction.Adopting proper seismic mitigation measure can effectively reduce the seismic responses of bridge.The finite element model of a three-span simply supported box beam bridge is established.Eight groups of magnetorheological dampers are set on the bearings and extension seams of bridge.With the combination application of plate rubber bearings and magnetorheological dampers,decreasing seismic effectiveness of active control,semi-active control and passive control for simply supported box beam bridge is analyzed under different ground motion inputs.The results indicate that decreasing seismic effectiveness of semi-active control is remarkable and close to decreasing seismic effectiveness of active control.Decreasing seismic effectiveness of semi-active control is better than that of passive control with most damping force all along for the integer bridge.It can be used as a reference for the application of semi-active control dampers in earthquake resistance of simply supported beam bridge theoretically.