WIDE BAND ULTRASONIC SEARCH METHOD FOR CONCRETE ELECTRIC POLE UNDERGROUND PART BASED ON MACROSCOPIC SEARCH THEORY

摘要

PROBLEM TO BE SOLVED: To provide a method for a person to easily search for and measure cracks in an underground part of an electric pole even if the person has not sufficient knowledge and experiences.;SOLUTION: The ultrasonic search method to search for cracks in an underground part of a concrete electric pole having a hollow part therein includes a step of finding a received wave G_j(t) by performing a multitude of times of reception at respective survey points, a step of preparing a crack calibration wave Gw(t), a step of correcting differences in the amplitude of G_j(t), a step of finding a narrow-band spectrum FA_j(f) to find corresponding GA_j(t) and calculating a t₁ value each time a distance 1 is inputted, a step of finding new GA_j(t) for analysis by using a CG(1) function, and a step of finding GB_j(t) by using a filter function. With GB_nA+1(t) maximally displayed, GB_j^nS(t) is comparatively displayed. When an evaluation segment crosses the wave of the GB_j^nS(t), it is determined at its measurement point j that cracks exist within the distance 1 or onward. Measurement is performed on whether the cracks exist and on a distance 1 to the cracks with a 1 value gradually increased.;COPYRIGHT: (C)2008,JPO&INPIT