Method and apparatus for measuring the degree of cable corrosion

摘要

A detecting coil device mounted on part of a cable to evaluate the degree of corrosion of the cable, which is used, for example, on suspension or skew bridges. The detecting coil device is provided with a detecting coil and Hall elements. A magnetizer having a magnetizing coil is mounted as to enclose the cable and the detecting coil device. When current flows through the magnetizing coil, it magnetizes the cable. The magnetic field strength is detected by the Hall element, and the amount of magnetic flux passing through the cable is detected using the detecting coil. The cross-sectional area of the cable is also calculated on the basis of the magnetic field strength and the amount of magnetic flux which are detected and the permeability of the cable. The degree at which the cross-sectional area of the cable is decreased (the corrosion degree) is evaluated by comparing the calculated cross-sectional area of the cable with the cross-sectional area of a reference cable.