On a six selected species of wood - spruce, ash, oak, beech, walnut and cherry- all test specimens were moistened and dried, we investigated changes in the following modules: fundamental frequency, sound damping and elasticity. The method used was resonance with elastic mechanical excitation. We came to conclusion, that modulus of elasticity in drying process changed two times faster than in the moistening process. With moisture increasing, the sound damping coefficient was decreasing, but changes have not been proved statistically important. Lowest sound damping was detected in spruce, cherry and ash. The change in modulus of elasticity was in linear dependency with average moisture content, while response of sound damping was faster. We concluded, that this is due to the moisture gradient.
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