基于磁耦合谐振涡流的混凝土保护层厚度检测

Thickness detection of concrete cover based on magnetic coupling resonance eddy current

为准确测量混凝土保护层厚度,确保结构的耐久性和安全性,提出了一种基于磁耦合谐振涡流检测混凝土保护层厚度的方法。首先建立等效电路模型,分析磁耦合谐振增强检测信号的内在机理,通过有限元仿真和试验验证了磁耦合谐振对检测信号的增强作用。开展了基于磁耦合谐振涡流的混凝土保护层厚度检测试验,检测误差小于6%,表明该方法可对混凝土保护层厚度进行有效检测。相较于传统的涡流法,通过双线圈结构的传感器可将检测信号转换为易于测量、分析的电信号,通过调试频率形成磁耦合谐振,显著增强了检测信号,提高了探测距离及灵敏度,为混凝土保护层厚度的高精度检测提供了新思路。

In order to measure the thickness of concrete cover accurately and ensure the durability and safety of the structure,a magnetic coupling resonance eddy current testing method was proposed.Firstly,the equivalent circuit model was established,and the internal mechanism of the enhancement of the detection signal by magnetic coupling resonance was analyzed.The enhance-ment of the detection signal by magnetic coupling resonance was verified by finite element simulation analysis and experimental re-search.The test of concrete cover thickness detection based on magnetic coupling resonance eddy current was carried out,and the detection error was less than 6%,which indicated that the method can effectively detect the concrete cover thickness.Compared with the traditional eddy current method,the detection signal can be converted into the electrical signal which is easy to measure and analyze by the sensor with double coil structure.The magnetic coupling resonance is formed by adjusting the frequency,which significantly enhances the detection signal,improves the detection distance and sensitivity,and provides a new idea for the high-precision detection of concrete cover thickness.