TY - JOUR
T1 - Acoustoelastic effect of wood III
T2 - Effect of applied stresses on the velocity of ultrasonic waves propagating normal to the direction of the applied stress
AU - Hasegawa, Masumi
AU - Sasaki, Yasutoshi
AU - Iwata, Toshihiro
PY - 2000
Y1 - 2000
N2 - Changes in the velocity of ultrasonic waves propagating in wood normal to the direction of applied stresses are discussed. The ultrasonic modes considered here are longitudinal waves and shear waves with particle motion along the direction of the applied stress. The ultrasonic velocities in wood were measured by the sing-around method. From the results of the acoustoelastic experiments in wood, changes in the ultrasonic velocities were expressed as a function of the applied stress. For the shear waves, the ultrasonic velocities decreased with an increase in compressive stress from the initial stress level. On the other hand, the ultrasonic velocities under tensile stress increased with an increase in stress at low stress levels and then gradually decreased with further a increase in the stress. In contrast, the longitudinal wave velocities increased with an increase in compressive stress at low stress levels and then decreased with additional increase in the stress. The wave velocities under a tensile stress decreased with an increase in the stress. The proportional relations between velocities and stresses at low stress levels are confirmed, and acoustoelastic constants were obtained from these relations. Their absolute values were smaller than those reported in previous studies but larger than those of metals. The acoustoelastic effect seemed to be almost equivalent on the sensitivity for stress measurement as the strain-gauge method.
AB - Changes in the velocity of ultrasonic waves propagating in wood normal to the direction of applied stresses are discussed. The ultrasonic modes considered here are longitudinal waves and shear waves with particle motion along the direction of the applied stress. The ultrasonic velocities in wood were measured by the sing-around method. From the results of the acoustoelastic experiments in wood, changes in the ultrasonic velocities were expressed as a function of the applied stress. For the shear waves, the ultrasonic velocities decreased with an increase in compressive stress from the initial stress level. On the other hand, the ultrasonic velocities under tensile stress increased with an increase in stress at low stress levels and then gradually decreased with further a increase in the stress. In contrast, the longitudinal wave velocities increased with an increase in compressive stress at low stress levels and then decreased with additional increase in the stress. The wave velocities under a tensile stress decreased with an increase in the stress. The proportional relations between velocities and stresses at low stress levels are confirmed, and acoustoelastic constants were obtained from these relations. Their absolute values were smaller than those reported in previous studies but larger than those of metals. The acoustoelastic effect seemed to be almost equivalent on the sensitivity for stress measurement as the strain-gauge method.
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U2 - 10.1007/BF00777355
DO - 10.1007/BF00777355
M3 - Article
AN - SCOPUS:0034043016
SN - 1435-0211
VL - 46
SP - 102
EP - 108
JO - Journal of Wood Science
JF - Journal of Wood Science
IS - 2
ER -