RESEARCH ON THE DISTRIBUTION OF MAGNETIC FIELD IN REINFORCED CONCRETE BEAMS AFTER DAMAGE BASED ON THE FORCE–MAGNETIC COUPLING MODEL, 130-137.

Yu-chao Xia and Zhen Li

Keywords

Damage mechanics, force–magnetic coupling, permeability

Abstract

In this paper, aiming at the problem of corrosion damage of steel bars in reinforced concrete beams, the research of damage detection of steel bars in bridges based on magnetic memory effect is carried out. Based on the theory of magnetic dipole model and COMSOL software programming, the magnetic field distribution of magnetic memory in reinforced concrete beams after steel corrosion is studied. The magnetic force is firstly loaded by COMSOL, and then the finite element electromagnetic (EM) analysis is carried out according to the magnetic–force coupling model. The results show that the normal component of the leakage magnetic field crosses the zero point, and the tangential component has a peak value, which indicates that the steel bar has plastic deformation and the internal magnetic domain structure has an irreversible rearrangement. Furthermore, it leads to the change of the permeability of the steel bar and finally leads to the change of the magnetic field of specimen. By comparing the other experimental results, it is verified that the proposed model could effectively describe the magnetization change trend of the specimens during the damage process. The simulation well explains the feasibility of magnetic memory detection of reinforcement damage, thus proving the applicability of the force–magnetic coupling model.

Important Links:



Go Back