목재의 음향신호전달에 미치는 함수율과 섬유방향의 영향

The Effect of Moisture Content and Grain Direction on the Propagation of Acoustic Signals in Wood

The estimation of the effect on the generation and propargation of acoustic signal need to evaluate the strength properties and/or detect the defect of wood, wood based-material and/or wood construction by the non-destructive testing method(acoustic emission, acousto-ultrasonic). This study was performed to clarify the effect of moisture content and grain direction on the characteristics of propagated AE wave signal using destruction of sharp pencil lead and two species of Pinus densiflora Siebold et Zuccarini and Castanea crenata Siebold et Zuccarini was used. These results indicated that, AE signal count was much more attenuate across the grain direction than along the grain direction in the both species. AE wave signal across the grain direction in a tangential section of Pinus densiflora was the most attenuate. The higher moisture content, the more effective to attenuation of AE signal, whereas the moisture content ,vas less effective across the grain direction. The charactfristics of AE wave signal count was very similar to its energy.