In timber exposed to moisture variations, shape instability is a serious problem since it can make the wood products obtained unsuitable for construction purposes. Two characteristics of wood are that its behaviour is. strongly orthotropic and that it is very sensitive to variation in moisture. In addition, wood is characterized by variation in its properties from pith to bark. A further important property of wood which affects its behaviour is its spiral grain. In addition, in timber containing much compression wood, drying distortion is highly dependent upon where the compression wood is located in the board. The present study concerns an experimental investigation of density, grain angles, shrinkage parameters and longitudinal elastic modulus in a number of spruce boards containing compression wood. On the basis of the data obtained, numerical simulations were carried out to determine the deformations that developed in the boards during changes in moisture. The knowledge thus obtained can facilitate more effective use of the raw material through enabling boards with properties yielding poor shape stability to be sorted out.
|Title of host publication||Wood Drying Research & Technology for Sustainable Forestry Beyond 2000|
|Publication status||Published - 1999|
|Event||6th International IUFRO Wood Drying Conference - Stellenbosch, South Africa|
Duration: 25 Jan 1999 → 28 Jan 1999
Conference number: 6
|Conference||6th International IUFRO Wood Drying Conference|
|Period||25/01/1999 → 28/01/1999|