Research On Detection Method Of Steel Location And The Depth Of Coverage In Reinforced Concrete Structure

The pulsed eddy current testing technology is a new emerging nondestructive testingtechnology. Its excitation is a pulse signal with wide frequency band. The detected signal hasrich frequency information, so this detection technology has a wide application prospect. Thispaper applies it to detect the steel location and the depth of coverage in reinforced concretestructure, and good results have been achieved.In this paper, the working principle of PEC transducer is elaborated on the basis of thefunction principle and theory foundation of PEC. Eddy current testing system is divided into twoparts which includes hardware and software design. With high precision of the A/D C8051F350MCU as the control center, the hardware includes the coil driving circuit, signal conditioningcircuit, data acquisition circuit and alarming circuit. The software includes the main program,interrupt program of data acquisition. The paper simulates the electromagnetic properties of eddycurrent sensor using the magnet finite element analysis software, which provides a basis for theprobe design. According to the characteristics signal, the quantitative measurement of steellocation and concrete cover thickness is accomplished. By the experiment, we find the closerelationship between the inductive voltage signal and detection distance. The test proves thefeasibility of PEC testing technology in testing the steel location and concrete cover thickness.