摘要
为解决Lamb波用于检测板类焊接结构疲劳损伤时受到多模态特性限制的问题,对Lamb波在无损和带损伤钢桥面板中的传播过程进行数值仿真分析。利用MATLAB软件计算Lamb波频散方程,得到对称模态和反对称模态下的群速度和相速度的频散曲线,并采用Hanning窗函数对Lamb波信号进行处理;以U肋-顶板节点疲劳损伤为例,基于Abaqus软件模拟Lamb波在无损和带损伤钢桥面板的传播过程,得到相应的幅值曲线,并通过小波分析确定钢桥面板的时频信号分布状态。结果表明:使用同一频率Lamb波检测时,有损信号的幅值增大;采用不同频率Lamb波检测带损伤钢桥面板,Lamb波的激励频率越高,信号幅值越大。200 kHz Lamb波相比150 kHz Lamb波的时频分布差异明显,且能量分布愈加集中,更利于实现损伤的精确定位,推荐采用200 kHz Lamb波检测钢桥面板的疲劳损伤。
To address the issue of multimodal characteristics limiting the use of Lamb waves for detecting fatigue damage in plate-like welded structures,numerical simulation analysis is conducted on the propagation process of Lamb waves in steel bridge decks with and without damages.Utilizing MATLAB software to calculate the Lamb wave dispersion equation,the dispersion curves of group velocities and phase velocities for both symmetric and antisymmetric modes are obtained.Additionally,a Hanning window function is employed to process the Lamb wave signals.Taking the U-Rib-Deck joint as an example,the propagation processes of Lamb waves in steel bridge decks with and without damages are simulated using Abaqus software.Corresponding amplitude curves are obtained,and the time-frequency signal distribution status of the steel bridge deck is determined through wavelet analysis.The results indicate that when detecting with Lamb waves of the same frequency,the amplitude of the damaged signal increases.Using Lamb waves of different frequencies to detect steel bridge decks with damage,the higher the excitation frequency of the Lamb waves,the greater the signal amplitude.Compared to 150 kHz Lamb waves,200 kHz Lamb waves in time-frequency distribution show a distinct difference,and energy distribution becoming more concentrated,which is more conducive to the precise detection of damages.It is recommended to use 200 kHz Lamb waves for detecting fatigue damages in steel bridge decks.
作者
田亮
王宇宁
赵健
徐正
孟俊良
TIAN Liang;WANG Yuning;ZHAO Jian;XU Zheng;MENG Junliang(Tianjin Key Laboratory of Civil Structure Protection and Reinforcement,Tianjin Chengjian University,Tianjin 300384,China;School of Civil Engineering,Tsinghua University,Beijing 100084,China;China Railway Construction Bridge Engineering Bureau Group Co.,Ltd.,Tianjin 300300,China)
出处
《世界桥梁》
北大核心
2024年第4期114-121,共8页
World Bridges
基金
国家自然科学基金项目(51708346)
中国铁建股份有限公司科技重大专项(2020-A01)
天津市企业科技特派员项目(22YDTPJC00210)。
关键词
桥梁工程
钢桥面板
疲劳损伤
LAMB波
频散曲线
超声无损检测
数值仿真
bridge engineering
steel bridge deck
fatigue damage
Lamb wave
dispersion curve
ultrasonic non-destructive testing
numerical simulation
