混凝土中的Lamb波传播  

Lamb Waves Propagation in Concrete

作　　者：孙明清[1] Staszewski W J Swamy R N 

机构地区：[1]武汉理工大学理学院,武汉430070 [2]谢菲尔德大学机械工程系

出　　处：《武汉理工大学学报》2004年第1期31-34,共4页Journal of Wuhan University of Technology

基　　金：国家留学基金;国家自然科学基金 (5 0 2 0 90 13)

摘　　要：将 PZT压电陶瓷片直接粘贴在混凝土梁表面来产生和接收超声波 ,由该系统发射不同频率的超声脉冲 ,依据接收的时域波形测量幅值最大波包在混凝土内的传播时间 ,由此得到波速随频率变化的频散关系。通过比较理论的与实测的频散曲线 ,表明 PZT系统能在混凝土内产生某些模态的 L amb波。在 5 0～ 10 0 k Hz的频率范围内 ,混凝土中的L amb波模态接近于 A3模态。而在 110～ 16 0 k Hz的频率范围内 ,L amb波模态接近 S4 模态。Lamb waves have been used for ultrasonic non-destructive testing of concrete due to their multi-mode characteristics and propagation over long distances. In this paper PZT patches are bonded on the surface of the concrete beam to launch and receive the ultrasonic wave. The proposed system transmits ultrasonic pulses with different frequencies. Then the relationship between the group velocity and frequency is obtained by measuring the time of flight of the wave package with the maximum peak-to-peak amplitude. Comparing calculated dispersion curves of Lamb waves with experimental results, it is found that Lamb waves can be generated in concrete with PZT patches, and Lamb modes are nearly to A_3 mode and S_4 mode in the range of 50~100 kHz and 110~160 kHz respectively.

关 键 词：LAMB波 压电陶瓷片 混凝土 频散关系 

分 类 号：TU317.8[建筑科学—结构工程]