多尺度结构动力方程及其在损伤识别中的应用

以一个三层框架结构为研究对象，分析了结构发生损伤时其动力参数的变化特征.应用小波变换，推导了多尺度结构动力方程来分析结构动力系统中的损伤识别.面向结构损伤识别，描述了多尺度动力方程能获得更丰富的结构参数变化信息.根据时变动力系统的结构损伤识别数值计算的特点，应用状态空间法来对结构损伤动力过程进行数值模拟.通过不同激励荷载下的损伤数值模拟和损伤时域识别，研究了多尺度损伤识别的两个关键性问题：不同位置的传感器对损伤预警的敏感性；系统输入荷载频率成分对损伤信息分布的影响.所进行的研究对于在基于小波分析的结构健康监测中合理选择传感器位置、采样频率及确定信号分解的尺度数具有理论指导意义.

Multi-scale structural dynamic equation and application of it in damage identification

By studying a structure of 3-story frame,the properties of dynamic parameters were investigated when damage occurred in structure.Applying wavelet transform,differential equation of multi-scale structural dynamic was obtained and the parameter recognition of damage identification was analyzed in structural dynamic system.For structural damage identification,it was described that the multi-scale dynamic equation can support more information of structural parameter variety than normal single dynamic equation.According to the feature of calculation of time-variety dynamic system in damage identification,the state space method was introduced to simulate structural damage progress.Finishing numerical simulation and temporal location of structural damage under different excitation load,two key problems were studied to be as follow: the sensitivity of signal of sensors from different location to damage alarming and the affection of frequency component of the excitement loads to distributing of damage information.The study has important significance in theory for reasonably to select sensor location,signal sampling frequency and scale of signal decomposing in structural health monitoring based on wavelet analysis.