基于提升小波变换和互相关函数的梁式桥损伤检测

On the Beam Bridge Damage Detection Based on Lifting Wavelet Transform and Cross Correlation Function

为了有效地提取梁式桥的损伤特征,提出了一种将提升小波变换与互相关函数幅值向量相结合的损伤识别的方法。首先利用提升小波变换将车载作用下梁桥结构的加速度响应分解到单阶模态上,再对提升重构后得到的第一阶响应进行互相关处理,利用提出的损伤指标来进行损伤定位。通过数值仿真和模拟实验,验证了方法的有效性,讨论了噪声及测点稀疏对识别结果的影响,结果表明该方法具有良好的噪声鲁棒性。另外,在综合考虑经济性和识别结果准确性的情况下,给出了合理的测点布置方式。

In order to effectively extract the damage features of beam bridge, a damage identification method is proposed in this paper, based on the combination of lifting wavelet transform and cross correlation function amplitude vector. Firstly, the acceleration response of beam bridge under vehicle Loading was decomposed to single mode by lifting wavelet transform; secondly, the first order response of lifted reconstruction was processed by cross-correlation to obtain damage index, which was used to damage localization. Through numerical simulation and simulation experiments, the effectiveness of this method was verified, and the influence of noise and sparse measurement points on identification results is discussed. Results show that this method has good noise robustness. In addition, reasonable arrangement of measuring points is provided in this paper, under conditions of comprehensively considering the cost and accuracy of identification results.