在移动荷载作用下基于小波包变换的桥梁损伤识别

Bridge Damage Identification Based on Wavelet Packet Transform under Moving Loads

提出了一种在移动荷载作用下基于小波包能量的桥梁结构损伤识别方法.运用Ansys软件进行不同损伤工况数值模拟,得到不同工况下的不同测点的加速度时程曲线,利用Matlab对不同测点处的加速度时程曲线进行小波包分量能量分析,然后通过损伤指数(DI)识别损伤发生的位置.本文主要研究了不同损伤程度、不同荷载移动速度、不同小波函数、不同的分解层次对损伤识别结果的影响.数值模拟结果表明:该方法对局部损伤具有较强的敏感性,损伤指标具有鲁棒性,可以准确获得损伤的位置.

A damage identification method for bridge structures based on wavelet packet energy under moving loads is proposed in this paper.The Ansys software is used to numerically simulate the different damage conditions,and the acceleration time history curves of different measuring points under different working conditions are obtained.The wavelet packet component energy analysis is performed on the acceleration time history curve at different measuring points by Matlab,and then the damage occurrence position is identified by the damage index(DI).This paper mainly studies the effects of different damage degrees,different moving load speeds,different wavelet functions,and different decomposition levels on damage identification results.The numerical simulation results show that the method has strong sensitivity to local damage,the damage index is robust,and the location of the damage can be accurately obtained.