大跨度拱桥基于降阶模型的半主动鲁棒控制  

H_∞Robust semi-active control for a long-span arch bridge based on a reduced order model

作　　者：李正英[1] 熊辉[1] 

机构地区：[1]重庆大学土木工程学院,重庆400045

出　　处：《振动与冲击》2010年第1期117-120,182,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金(50908245/E080805)

摘　　要：将磁流变阻尼器用于拱桥的减震控制,首先在模态分析的基础上对大跨度拱桥进行模型降阶,以用于控制系统设计。为解决大跨度拱桥降阶控制中模型简化而导致的未建模频域不确定性所引起的溢出问题,采用基于混合灵敏度的鲁棒控制策略来消除溢出不稳定。结合基于Sign函数的半主动控制算法,建立了拱桥磁流变阻尼器半主动鲁棒控制策略。最后,以西藏尼木大桥作为算例,对该拱桥采用上述半主动鲁棒控制和LQG半主动控制方法进行了减震控制分析比较。数值分析结果表明,该方法与通常的LQG控制方法相比,能有效的抑制溢出,保证系统具有更好的鲁棒性能。Here,a magnetorheological Fluid damper(MRFD) was used for seismic control of an arch bridge. Firstly,model reduction of a long-span arch bridge was implemented based on modal analysis in order to design a semi-active control system.In order to solve the problem of spillover due to uncertainties of the reduced order structural system in unmodeled frequency domain,which might lead to destabilization of the control system,a robust control strategy based on H_∞mixed sensitivity was proposed to eliminate spillover instability.And then,sign function-based H_∞semi-active control algorithm was applied to command the MRFD.The Nimu arch bridge was used as a simulation example to verify the proposed control scheme.Numerical simulation results demonstrated that,in contrast to the conventional LQG semi-active control method,this method can suppress spillover instability efficiently and has better robust performance.

关 键 词：拱桥 磁流变阻尼器 H∞鲁棒控制 溢出不稳定 

分 类 号：TU352.1[建筑科学—结构工程] U448.22[建筑科学—桥梁与隧道工程]