Evaluation of the Degree of Corrosion of Parallel Reinforcement Bars from Their Magnetic Fields

Analytic expressions for the components of the magnetic field strength of double two-layer cylindrical inclusions in an isotropic medium are derived. It is shown that the contribution of corrosion of reinforcement bars of building structures to the resulting leakage magnetic field is commensurable with the change in the magnetic field due to the interaction between the bars and that change in the magnetic field of a corroding bar is transferred to neighboring bars due to the magnetic interaction.