Changes In Shrinkage And Tangential Compression Strength Of Sugar Maple Below And Above The Fiber Saturation Point


  • Roger E. Hernández
  • Michal Bizoň


Moisture sorption, desorption, fiber saturation point, wood strength, compliance coefficient, shrinkage, sugar maple


Two experimental techniques were used to conduct moisture sorption tests in sugar maple sapwood. The first used saturated salt solutions (from 58% to 90% relative humidity) and the second used the pressure membrane method (above 96% relative humidity). These sorption tests were combined with dimensional measurements and perpendicular-to-the-grain tangential compression tests. Results indicated that at the equilibrium moisture content, radial, tangential, and volumetric shrinkage, as well as changes in transverse strength, occur above the nominal fiber saturation point. These results can be described by the effect of hysteresis at saturation on wood properties. This hysteresis implies that loss of bound water takes place in the presence of free water. The initial equilibrium moisture content at which bound water is removed from sugar maple wood was found to be 42.5%.


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