Magnetic shipboard damage evaluation method and damage evaluation device

摘要

The damage evaluation device 1 is installed and used on a concrete structure in which a tendon 10 to be evaluated for damage is installed and used, and a magnetizer 20 that generates a magnetic force, and a tendon that is magnetized by the generated magnetic force ( 10) detectors 41F and 41R that detect the amount of magnetic change generated from the damaged location. The magnetizer includes an excitation coil 24, an iron core 26 inserted through the center hole of the excitation coil, and a pair of column yokes 31F and 31R connected to both ends of the iron core and extending toward the concrete surface, respectively. Include. By allowing current to flow through the excitation coil, a magnetic circuit is formed by a yoke shaft, a pair of columnar yokes, and a tendon in a range located between the pair of columnar yokes. The current flowing through the excitation coil is controlled so that the magnetic flux density of the tendon becomes constant.