环境激励下房屋建筑的阻尼比识别  

STUDY ON IDENTIFICATION OF DAMPING RATIO FOR THE BUILDING UNDER AMBIENT EXCITATION

作　　者：谭高铭[1] 张之颖[1] 吕西林[2] 

机构地区：[1]西安交通大学人居环境与建筑工程学院,西安710049 [2]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《工业建筑》2008年第z1期182-184,158,共4页Industrial Construction

基　　金：土木工程防灾国家重点实验室重点基金项目(2005-A-02)

摘　　要：阻尼比的准确取值一直是结构动力分析的难点,由于阻尼机理非常复杂,对阻尼比的取值一般通过实测得到。传统的模态参数识别方法需要同时利用激励和响应信号,但对实际建筑结构,激励施加存在困难。探讨了基于环境激励下的模态识别方法,利用环境激励(如施工机械振动、风、车辆、行人、地脉动等)下的结构振动响应数据,采用随机子空间(Stochastic Subspace Identification)法,有效地识别实际建筑结构的模态参数的方法。工程实例的模态参数识别结果表明,该方法不仅能准确识别出结构的模态频率,还能相对准确地得到结构的模态阻尼比。Exactly measuring damping ratio is difficult for dynamic response analysis all the time,Because the mechanism of damping is very complex,the damping ratio is usually obtained by measuring.For the traditional mode parameter identification method,exciting signal and response signal are necessary.But to excite a real structure and then getting the response signal can't be realized.It is proposed a new mode parameter identification method based on environmental exiting.We measured the structure response excited by environmental factors such as constructional machine vibration,wind,vehicles,walkers,microtremors and so on.The structure response data is analyzed by SSI(stochastic subspace identification).The results show that this new method could not only exactly identity the structure vibration frequency,but also obtain the mode damping ratio.

关 键 词：阻尼比 环境激励 模态识别 随机子空间 

分 类 号：TU311.3[建筑科学—结构工程]