A Simulation and Experimental Study Investigating 2D Magnetic Flux Leakage (MFL) for Defects in Reinforcing Steel

Abstract

The study examines magnetic flux leakage signals (B_x, B_y) within D₁₉ sized rebars in two dimensions. An economically designed test setup incorporating permanent magnets was used to collect magnetic flux leakage at the defect location. The numerical simulation was performed using COMSOL Multiphysics on a 2D finite element model. This study also attempts to enhance defect analysis by using the MFL signals (B_x, B_y). As defect width increases, the x-component of the signal (B_x) increases, and with depth, the y-component (B_y) increases. Even though depth and width interact in signal appearance, the overall amplitude variation was sufficient to predict the defect area. R²=0.9079 indicates a higher coefficient of regression for x-component (B_x) amplitudes in defect areas. A positive correlation between defect position, geometry, and shape was found.