双通道冲击回波无损检测响应特性研究

Study on Impact Echo Response Characteristics of Dual Channel Nondestructive Testing

传统冲击回波法多采用单通道检测,但土木工程结构往往尺寸较大,采用单通道检测效率较低。为了提高检测效率,本文提出了双通道冲击回波采集的方法,并采用ABAQUS有限元软件建模分析了不同通道距离工况下冲击回波的响应特性,为多通道冲击回波方法的进一步应用奠定了基础。研究结果表明:对于无缺陷结构,两个通道间的距离对冲击回波峰值频率位置几乎没有影响;对于有缺陷模型结构,当两通道均布置在缺陷上方时,频率峰值位置受两通道距离影响较小,当有一个通道位于缺陷上方时,该通道峰值频率表现为两个冲击回波峰值频率的叠加。

The traditional impact echo method to detect flaws often use a single excitation source signal and a single sensor to receive the transmission signal.When testing large components,the efficiency of single channel detection is greatly reduced.In order to improve the detection efficiency,dual channels impact echo method was proposed in this paper,and the impact echo response was analyzed using ABAQUS finite element software.It was found that the channel distance has limited influence on intact structures,while on structure with flaws and dual peak frequencies were observed.