压电陶瓷片用于检测混凝土的波速和动弹模  

Using Piezoceramic Patches to Measure the Velocity of Waves and Dynamic Mechanical Constants of Concrete

作　　者：孙明清[1] STASZEWSKIW 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6期1-4,共4页Journal of Wuhan University of Technology

基　　金：国家留学基金和国家自然科学基金 (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 ,从接收的时域信号中能清晰分辨沿混凝土梁表面传播的纵波和 Rayleigh波 ,并以此确定 Rayleigh波和纵波在混凝土表面的传播时间和波速 ,再由 Rayleigh波和纵波波速计算混凝土的动弹性模量和动泊松比。PZT片产生的沿表面传播的纵波和 Rayleigh波用于混凝土内结构缺陷监测时 ,合适的频率范围分别为 12 0～ 2 0 0 k Hz和 5 0～ 110 k Hz,并且 Rayleigh波波速在 5 0～ 80 k Hz的频率范围内呈现出明显的频散特性 ,即波速随频率而变化。Two PZT patches are bonded on the surface of the concrete beam to launch and to receive the ultrasonic wave.P waves and Rayleigh waves propagating along the surface of concrete can be identified on the waveform,and the time of flight of P waves and Rayleigh waves can be measured.The dynamic modulus of elasticity and Poisson′s ratio can be calculated after obtaining the velocity of P waves and Rayleigh waves.Results show that it is a simple process to measure the velocity of P waves and Rayleigh waves and dynamic mechanical constants.When this PZT ultrasonic system is used to detect the internal defects in concrete,the most suitable frequency scopes are 120～200 kHz and 50～110 kHz for P waves and Rayleigh waves respectively.Dispersion of Rayleigh waves is observed in the range of 50～80 kHz,which is,the velocity of Rayleigh waves depending on the frequency.

关 键 词：压电陶瓷 混凝土 超声波波速 频散 结构健康检测 

分 类 号：TU528.01[建筑科学—建筑技术科学]