We studied selected physical properties of oak (Quercus sp.) timber after aging. We investigated wood of various ages, from recently felled to that felled more than 600 years ago. We obtained it from several locations in Slovenia. Oriented wood specimens of dimensions 40 x 40 x 5 mm from the inner part of the beams were dendrochronologically dated. We determined wood density, colour (visual assessment and CIELab standard), dimensional stability and sorption properties. We have visually assessed that the colour of the oak heartwood increased with age. This was confirmed by linear decrease of colour lightness L* with wood aging. Dimensional stability in tangential direction increased, while the shrinkage anisotropy and the sorption coefficient decreased with age. Changes of dimensional stability of aged oak wood in radial direction were not confirmed. The equilibrium moisture content of oak wood decreased with aging throughout the whole hygroscopic range, and the sorption hysteresis decreased. The density of oak wood did not change with age. Irrespective of wood age, the density increased with increasing growth ring width and proportion of latewood. The research also confirmed great influence of local conditions on dimensional stability and hygroscopicity of wood during its service time.
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