Detecting the Diameter and the Depth of Steel Reinforcing Bar in Concrete Using Electromagnetic Method


  • Dongfeng He National Institute for Materials Science, Sengen 1-2-1, Tsukuba, 305-0047, Japan


steel reinforcing bar, electromagnetic method, concrete, nondestructive evaluation, corrosion


When corrosion happens with the steel reinforcing bar (rebar) in concrete, the diameter of the steel rebar is reduced. It is possible to judge the corrosion of the steel rebar by measuring the diameter of the steel rebar nondestructively. We developed an electromagnetic method to detect the diameter and depth of the steel rebar in concrete simultaneously. In this method, the eddy current testing method with two probes was developed. To avoid the interference between the two probes, two excitation frequencies of 3.8 kHz and 4.2 kHz are used. With this system, it was possible to evaluate the depth and the diameter of the steel rebar and the resolution of better than 1 mm was obtained. 


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How to Cite

He, D. (2022). Detecting the Diameter and the Depth of Steel Reinforcing Bar in Concrete Using Electromagnetic Method. International Journal of Applied Sciences: Current and Future Research Trends, 15(1), 120–128. Retrieved from