METHOD OF ULTRASONIC FLAW DETECTION FOR HOLLOW CONCRETE COLUMN

摘要

PROBLEM TO BE SOLVED: To accurately detect the presence of a defect such as a crack initiated in a buried part of a hollow concrete column and to accurately specify the position of the defect. SOLUTION: In detecting the crack K initiated in the buried part Ca of the hollow concrete column CP constructed with the lower side buried in the ground M, an ultrasonic transmitter 1a and an ultrasonic receiver 1b are arranged on the surface of the ground part Cb of the concrete column CP, in this order from the buried part Ca side in the axial direction of the concrete column CP so as to have a specified clearance L, and the ultrasonic transmitter 1a and ultrasonic receiver 1b are arranged by oblique jigs 2 so that the ultrasonic emission-incidence directions point to the buried part Ca.