Non-destructive testing method of fiber content in steel fiber reinforced concrete based on magnetization loss

•The feasibility of detecting steel fiber content by eddy current method was explored.•The electromagnetic field numerical model of steel fiber reinforced concrete was established.•The relationship between the electrical parameters of the excitation coil and the fiber content was established. Steel fiber reinforced concrete (SFRC) has been widely used in construction engineering due to its superior crack resistance and flexural capacity. Its mechanical properties mainly depend on the distribution of fibers, and the uneven distribution will reduce the structural performance. Therefore, this paper proposed a fast non-destructive testing method for steel fiber content evaluation based on magnetization loss. This method could solve the problem that the traditional methods were difficult to detect in situ. It is found that the higher the steel fiber content, the greater the magnetic loss and electrical loss of the fiber under sinusoidal excitation, resulting in the changes of the excitation coil impedance. Based on this phenomenon, the impedance difference modulus and quality factor evaluation index of the excitation coil are proposed, which can be used to accurately estimate the internal fiber content of concrete in-situ detection. The feasibility of the method is verified by experiments, which is of great significance to the quality control in the manufacturing process of SFRC.