考虑补偿的多自由度实时耦联动力试验时滞稳定性分析  

DELAY-DEPENDENT STABILITY ANALYSIS OF MDOF REAL-TIME DYNAMIC HYBRID TESTING CONSIDERING COMPENSATION

作　　者：迟福东[1] 王进廷[1] 汪强[1] 金峰[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《工程力学》2011年第4期200-207,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(90510018;50779021;90715041);水沙科学与水利水电工程国家重点实验室自主研究课题项目(2008-TC-2);地震行业科研专项(200808008)

摘　　要：该文首先建立考虑振动台响应时滞和时滞补偿策略的多自由度实时耦联动力试验的数学模型。然后以二层和三层框架结构为例,采用基于Padé展开逼近时滞项的根轨迹方法研究其稳定性。最后利用试验验证了理论分析得出的稳定条件。结果表明:时滞要求物理子结构和数值子结构的质量比小于一定的临界值才能保证试验的稳定;该临界值随时滞和结构自振频率的增大而降低,随结构阻尼比的增大而增大;在中低频段,三阶多项式补偿有利于提高这一临界值。Firstly,the mathematical model of a real-time dynamic hybrid test of a MDOF structure considering the shaking table response delay and compensation strategy is established.Then,as demonstrating examples,the delay-dependent stability conditions of a 2-storey structure and a 3-storey structure are investigated using the root locus technique based on Padé decomposition approximating the delay term.Finally,some tests are performed to validate the obtained stability condition.The results show that because of the delay,a stable test can be guaranteed only if the mass ratio of the experimental substructure to the numerical substructure is smaller than a critical value;a third-order polynomial compensation improves this critical value for a low or middle frequency structure.

关 键 词：结构试验技术 实时耦联动力试验 多自由度 根轨迹方法 时滞 稳定性 

分 类 号：TU317[建筑科学—结构工程]