论文部分内容阅读
结构的模态参数,特别是结构的振型,是结构损伤识别与健康监测的重要前提。本文利用自然环境激励而引起的振动来识别结构的模态参数,根据各测点的振动时域曲线,分析获得该测点的功率谱密度曲线,由曲线的峰值确定各阶固有频率、各测点振型值,以参考基准点为振型单位值作归一处理,由测点相对于参考基准点的相位,计算出各阶模态振型。并通过有限元计算分析,与实测模态振型对比。结果表明:实测方法与有限元结果基本吻合,大桥动力性能可靠。
The modal parameters of the structure, especially the mode shapes of the structures, are important prerequisites for structure damage identification and health monitoring. In this paper, the vibration caused by natural environment excitation is used to identify the modal parameters of the structure. According to the vibration time-domain curve of each measuring point, the power spectral density curve of the measuring point is obtained. The natural frequency of each step is determined by the peak of the curve. The point vibration type value is referenced to the reference point for the unit value of modalities for normalization. The phase mode of the measurement point relative to the reference point is used to calculate the modal shapes of each step. And through finite element analysis, compared with the measured mode shape. The results show that the measured results agree well with the finite element results and the dynamic performance of the bridge is reliable.