A procedure to determine water absorption distribution in wood composite panels

Abstract

A procedure is presented to determine the water absorption distribution of composite panels. The procedure is based on the direct measurement of the vertical density distribution before water soak, the vertical density distribution after the water-soaked specimens have been reconditioned to pre-soak weights, and the construction of the vertical density distribution for the specimens immediately after water soak. The separation of wood mass and water was achieved through the application of radiation absorption principles involving the two elements. The procedure was used to examine the water absorption distributions of medium density fiberboard, oriented strandboard, and particle-board. A good agreement was obtained between the estimated average water absorptions and measured water absorptions. Water absorption distribution in relation to the layer density and layer thickness swell was discussed.