| 摘要 |
PROBLEM TO BE SOLVED: To obtain a judgment method in which the exfoliation of a wall tile from a building is judged by a low-cost apparatus, quickly, with high accuracy, quantitatively and easily by a method wherein the surface of the tile is vibrated mechanically and vibrating levels at a plurality of frequency bands are recorded so as to be discriminated by using a specific expression. SOLUTION: By using an exciter 1, a tile 5 is scanned by using an apparatus in which an oscillation exciting roller 2 and a receiving disk 3 connected to an accelerometer 4 are arranged in parallel. When the existence of an exfoliation is discrimineted, levels at respective vibration octave bands in a plurality of known sound places and exfoliated places are measured. For example, levels at seven octave bands from 64Hz to 4kHz are measured, vibration levels at seven frequency bands are designated respectively as x1 to x7 , and factors a1 to a7 are set by using the discriminating analysis of expression I. Then, the same measurement is executed to a wall surface to be investigated, obtained data is substituted for expression I, the value of Ya is compared with a threshold, and the existence of an exfoliation is estimated. Then, by using expression II, values of factors b1 to b7 are set, the value of Yb obtained by substituting data for expression II is compared with a threshold, and the position of an exfoliation face is estimated. |
