Numerical and experimental investigation on the elastic stiffness of glued dovetail joints

Abstract

This study investigates the stiffness of dovetail joints by both numerical and experimental methods. Test specimens were made of Spruce (Picea abies L) and Beech (Fagus Silvatica L) wood, which were bonded with polyurethane (PUR) and polyvinyl acetate (PVAc) adhesives into dovetail joints. To determine the mechanical behavior, the joints were loaded according to grain direction under compressive and tensile load. The results of the experiment indicated that, under compression load, beech wood bonded with polyvinyl acetate (PVAc) adhesive had maximum elastic stiffness. Based on the experimental results, a numerical model using the finite element method (FEM) was developed by the Abaqus program to predict the stiffness of dovetail joints under compressive and tensile load. For numerical analysis, the assumption was made that arm deflection was caused by a displacement in the supports. The value of deflection corresponds to the limit of linear elasticity and the value of the force reduced stresses, which was determined on the basis of deflections. A cohesive zone was developed, which shows stress behavior under compressive and tensile load. A positive correlation was found between the numerical model and experimental study.