The Change of Ultrasonic Transmission Velocity by Wood Decay = The Change of Ultrasonic Transmission Velocity by Wood Decay

다국어 초록 (Multilingual Abstract)

The deterioration in wood by the brown-rot fungus (Fomitopsispalustris) and the white-rot fungus (Trametesversicolor) were measured using ultrasonic velocity. Those were used for the decay exposure and 4 wood species of wood as the test specimens, Pinusdensiflora, Larixkaempferi, Pinuskoraiensis and Pinusrigida, were chosen with both the brown- and white-rot culture petridish during 12 weeks. After 12 weeks, the decrease rate of ultrasonic velocity was measured at 10∼15%. In both brown-and white-rot exposure experiments, P. rigida showed significant decrease in ultrasonic velocity (20%), L. kaempferi on the other hand did not show decrease in ultrasonic velocity. After the fungal exposure experi-ment, the inside of specimens was investigated by computer tomography (C/T). After C/T investigation, bending tests were performed.