基于Wigner-Ville分布交叉项的独塔自锚式悬索桥损伤识别试验研究

Experimental study of single-tower self-anchored suspension bridge damage identification based on cross terms of Wigner-Ville distribution

为研究以Wigner-Ville分布的交叉项作为指标进行损伤识别效果,探究完整的提取交叉项方法,通过对二重余弦信号的Wigner-Ville分布推导,获得主项与交叉项的位置关系及交叉项震荡特性;据此设计相应的提取方法,将Wigner-Ville分布中各频率段正负能量分别沿时间轴积分,将正负能量之和绝对值作商,通过设定阈值进行筛选获得交叉项能量分布;以工程实例为研究对象,通过对比无、有损状态下对应测点交叉项能量差的突异点识别损伤位置与程度。试验结果表明,交叉项可作为损伤识别指标,且效果显著。

In order to investigate the effectiveness of using the cross terms of Wigner-Ville distribution to identify damage, a complete extraction of cross terms was explored. Through the derivation of Wigner-Ville distribution of a double cosine signal, the position relationship between main terms and cross terms, their concussion characteristics were negative energy was used to divide the positive one and a threshold was set for filtering and obtaining the energy distribution of the cross terms. An application was used to validate the method. The cross terms＇ energy difference of the observation point under non-damaged and damaged status were compared to determine the location and extent of damage. The result showed that the cross terms can be used as an effective damage identification index.