We have studied the stability of shape and dimensions of spruce wood and beech wood when exposed to various humidity factors: changing climatic conditions with relative humidity ranging between 33 % and 87 %, gradual drying from fresh to completely dry state and different equilibrium parameters. The dimensional changes of wood were evaluated by means of differential swelling and swelling coefficient in radial and tangential direction, and with transverse shrinkage anisotropy. After several repeated wetting and drying procedures it was established that the differences in equilibrium moisture content were reduced, resulting also in smaller dimensional terations and transverse shrinkage anisotropy. We confirmed the assumption that changing climatic conditions somewhat increase the stability of wood in terms of shape and dimensions.
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