Differences in acoustic velocity by resonance and transit-time methods in an anisotropic laminated wood medium
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Shakti Singh Chauhan
, Kenneth M. Entwistle und John C.F. Walker
Abstract
The influence of inhomogeneity on acoustic velocity measured by a resonance-based WoodSpec acoustic tool and a transit-time-based Fakopp-2D tool was investigated. Four laminated panels with different degrees of inhomogeneity were prepared and acoustic velocities were measured using both tools. Velocities measured by the Fakopp-2D tool were always higher than those measured by the WoodSpec tool in all panels. The difference in the two velocities was found to vary depending on the magnitude of inhomogeneity. It was demonstrated that the velocity measured by the resonance frequency obeys the law of mixtures and is controlled by the volume-weighted average stiffness of the material. In contrast, the velocity measured by the Fakopp-2D tool was the velocity of the pulse that first reached the detector travelling at the dilatational speed.
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- Hydrophobisation and densification of wood by different chemical treatments
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- Characterization of physiological functions of sapwood IV: Formation and accumulation of lignans in sapwood of Cryptomeria japonica (L.f.) D. Don after felling
- X-ray scattering studies of thermally modified Scots pine (Pinus sylvestris L.)
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- Parallel-plate rheology of latex films bonded to wood
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