基于小波包能量累积变异的梁桥损伤识别试验

Experiment on Damage Detection of Girder Bridge Using Wavelet Packet Energy Accumulated Variation

基于小波包分析方法可以捕捉到结构状态改变导致的频带能量分布变化的特征,提出了小波包能量累积变异指标来识别结构损伤,并将该指标应用到室内两跨连续梁模型桥的损伤识别中。车辆激励、锤击激励和环境激励3种不同激励源的测点实测加速度时程响应分析研究结果表明,激励信号能量大小的不同会导致小波包能量累积变异值的差异,联合多个测点响应的小波包能量累积变异指标值可以判别结构的不同损伤状态。

Based on the ability of catching the change of energy distribution in frequency band for changing in the structure condition by the wavelet packet analysis method,the wavelet packet energy accumulated variation index was proposed to detect the structural damage.The damage index was applied to the damage recognitions in a continuous two-span girder bridge model in the lab.The results of measuring acceleration time history from three different kinds of excitation ways,including vehicle excitation,environment excitation and hammer excitation, indicate that the amount of input energy has the influence on the value of wavelet packet energy accumulated variation index.Uniting more than one damage identification index results is possible to distinguish the different structural damage conditions.