Abstract
The drying stress in a longitudinally hollowed boxed-heart lumber was estimated using a linear finite element method (FEM). The drying stress due to the anisotropic shrinkage of wood was estimated with the aid of thermal stress analysis in orthotropic materials. The tensile drying stress due to the anisotropic shrinkage of wood concentrated at the middle of wider side surface of the hollowed lumber. In the case of the lumber whose pith was set off from the center of the cross section, higher tensile stress was found at the side surface nearer to the pith than at the other surface. This stress concentration was relieved by allocation of the hollow at the position of the pith.
