【作者】 张震；

【导师】 胡卫华；

【作者基本信息】 哈尔滨工业大学 ， 土木工程， 2023， 硕士

【摘要】 本文主要研究了高层结构动力特性自动跟踪技术和结构动力特性变化规律,采用理论推导、结构健康监测实测数据分析和有限元模型数值模拟分析等方式,以实验室5层框架结构和深圳市某大厦为研究对象,从基于数据预处理的结构模态响应数据获取、基于聚类算法的结构动力特性自动跟踪、高层结构动力特性变化规律研究三个方面展开研究,提出了高层结构动力特性自动跟踪技术,并在此基础上探究高层结构动力特性的变化规律。在基于数据预处理的结构模态响应数据获取方面,本文根据信号检测理论,对比结构健康监测系统中正常监测设备和异常检测设备采集信号,设计了能够有效实现异常监测设备智能识别与及时告警的预处理方案;结合理论推导,通过有限元模型模拟实验,论证了非白噪声环境激励能够在状态空间方程中产生虚假模态,提出了基于MVMD(Multivariate Variational Mode Decomposition)的采样信号自动归约方法,成功去除了非白噪声环境激励产生的虚假模态,实现了响应数据自动归约,为后续的数据分析提供有效的结构模态响应数据。在基于聚类算法的结构动力特性自动跟踪方面,本文结合理论推导、实验室5层框架结构以及其有限元模型模态试验、深圳市某大厦结构健康监测工程,提出和验证了基于Single-Pass聚类算法和OPTICS(Ordering Points to Identify the Clustering Structure)聚类算法的结构动力特性自动跟踪方法,成功识别出深圳市某大厦的3 Hz以下模态,并且利用模态识别结果建立并修正了该大厦顶部桅杆拆除后的有限元模型,成功实现了该大厦结构固有频率的自动跟踪。在高层结构动力特性变化规律研究方面,本文通过研究发现结构顶部桅杆拆除对超高层建筑主体结构主导的模态频率影响较小,振型基本一致,但是会导致由顶部桅杆参与主导的模态消失;温度影响下超高层结构固有频率与温度呈负相关,温度对频率影响不大,超高层结构顶部桅杆的存在对结构固有频率的温度影响有一定的削弱作用;台风影响下超高层结构固有频率有明显的下降趋势,风速越大结构固有频率越小,各阶模态固有频率变化率总体上差异不大,高阶模态固有频率随风速的变化量总体上要大于低阶模态。更多还原

【Abstract】 This paper mainly studies the automatic tracking technology of dynamic properties of high-rise structures and the variety rule of structural dynamic properties.By means of theoretical derivation,analysis of measured data of Structural health monitoring and numerical simulation analysis of finite element model,taking the 5-story frame structure of the laboratory and a building in Shenzhen as the research object,the automatic tracking of structural dynamic properties b ased on data preprocessing,structural modal response data acquisition based on clustering algorithm The research on the dynamic properties of high-rise structures has been conducted from three aspects,and an automatic tracking technology for the dynamic properties of high-rise structures has been proposed.Based on this,the variety rule in the dynamic properties of high-rise structures have been explored.In the aspect of data acquisition of structural modal response based on data preprocessing,according to the signal detection theory,this paper compares the signals collected by normal monitoring equipment and abnormal detection equipment in the Structural health monitoring system,and designs a preprocessing scheme that can effectively realize the intelligent identification of abnormal monitoring equipment and timely warning;Combined with theoretical derivation and finite element model simulation experiments,it is demonstrated that non-white noise environmental excitation can generate false modes in the state space equation,and an automatic reduction method of sampled signals based on multivariate variational mode decomposition(MVMD)is proposed,which successfully eliminates the false modes generated by non-white noise environmental excitation and realizes automatic reduction of response data,Provide effective structural modal response data for subsequent data analysis.In the aspect of automatic tracking of structural dynamic properties based on clustering algorithm,this paper proposes and verifies an automatic tracking method of structural dynamic properties based on Single-Pass clustering algorithm and ordering points to identify the clustering structure(OPTICS)algorithm,combining theoretical derivation,laboratory 5-story frame structure and its finite element model modal test,and a building Structural health monitoring project in Shenzhen,Successfully identified the mode below 3 Hz of a certain building in Shenzhen,and used the modal identification results to establish and correct the fini te element model of the building after the removal of the top mast,successfully achieving automatic tracking of the natural frequency of the building structure.In the aspect of studying variety rule in the dynamic properties of high-rise structures,this article found that the removal of the top mast of the structure has a relatively small impact on the dominant modal frequency of the main structure of super high-rise buildings,and the vibration modes are basically the same.However,it will lead to the disappearance of the dominant mode participated by the top mast;Under the influence of temperature,the natural frequency of super high-rise structures is negatively correlated with temperature,and temperature has little effect on frequency.The presence of the top mast of the super high-rise structure has a certain weakening effect on the temperature influence of the natural frequency of the structure.The presence of the top mast of the super high-rise structure has a certain weakening effect on the temperature influence of the natural frequency of the structure;Under the influence of typhoons,the natural frequency of super high-rise structures shows a significant downward trend.The higher the wind speed,the smaller the natural frequency of the structure.The overall difference in the variety rate of natural frequencies among different modes is not significant.The variety in natural frequencies of high-order modes with wind speed is generally greater than that of low-order modes.更多还原