Research on Detection Method of Effective Diameter of Defective Steel Bars in Concrete Structures

Reinforced concrete(RC) structures have become an indispensable building material in modern society, in which steel bars can significantly enhance the tensile and compressive properties of reinforced concrete integral components. When the steel bar diameter is reduced due to factors such as corrosion or manufacturing factors, the quality and service life of concrete members will be severely affected. Therefore, it is of great significance to accurately evaluate the effective diameter of reinforcing bars inside concrete members for the operation and maintenance of concrete members. Based on the magnetization principle of ferromagnetic materials, this paper innovatively proposes a detection method for judging the effective diameter of steel bars in concrete by using the magnetic induction value. The magnetic field distribution characteristics of steel bars with different diameters under a fixed magnetic field excitation source are studied, and the position of the diameter reduction interval is judged by the sudden change of the slope of the magnetic induction intensity curve. Curve fitting and integration were performed on the magnetic induction intensity values collected in the diameterreduced interval, and the ratio of the value to the curve integration under the normal diameter was used as the diameter criterion. Finally, by building an experimental platform, the validity of the criterion formed by the magnetic induction intensity curve for judging the diameter of steel bars in concrete is verified.