HYGROSCOPIC DEFORMATION OF WOOD-BASED COMPOSITE PANELS

A theoretical mechanics-based procedure was developed to predict the f ree hygroscopic deformation of wood-based composite panels. The experi mental validation of the procedure is described in this paper. APA- ra ted 5-ply plywood and OSB panels were exposed to 95 percent relative h umidity so moisture absorption could occur only from one side of the p anels. The cylindrical deformations in both directions (i.e., length a nd width) were measured and compared to the predicted values. Good agr eement was found between predicted and measured deformation.