【摘要】 为了减小纵飘桥梁在制动力和地震作用下产生的较大主梁纵向位移,以某大跨度自锚式悬索桥为工程背景,开展基于MR阻尼器的减振(震)控制研究。通过车辆制动力作用下的振动控制和3种地震波下的减震控制仿真分析,获得各自的期望控制;以加速度的变化率作为控制阀值,建立车辆制动力和地震荷载作用的减振(震)混合控制系统;最后将该系统应用于实桥的减振(震)仿真分析。结果表明:Passive-on控制和基于模糊理论的半主动控制分别为车辆制动力下和地震荷载下的期望控制;在车辆制动力、实桥地震波、EL-Centro波和Takochi-oki波等作用下,混合控制系统具有可靠有效的荷载识别能力,在合成的外干扰力作用下实现了期望控制,减振(震)效果显著。更多还原

【Abstract】 Since the longitudinal displacements of floating bridges subjected to dynamic loadings including vehicle braking forces or earthquake excitations maybe excessive, a hybrid control using MR dampers is investigated to mitigate the displacements. Firstly, the expected controls for vehicle braking forces and earthquake excitations are obtained, respectively. Then, a hybrid control system is established by the changing rate of accelerations. Finally, this system is applied in the longitudinal vibration responses reduction of a real bridge. The results show that the passive-on control and the semi-active fuzzy control are the expected controls for vehicle braking forces and earthquake excitations, respectively. The hybrid control has a good agreement with the expected controls for four dynamic loadings including the vehicle braking forces, the real bridge earthquake wave, the EL-Centro wave, and the Takochi-oki wave, so this system is reliable and effective. The hybrid control has the same performance as the expected controls for different loading combinations composed of vehicle braking forces and earthquake excitations.更多还原