The objective of this study was to determine the effect of wood density, adhesive type and gluing pressure on the shear strength of glued joints of fourteen commercial wood species. Wood pieces were classified in three density classes (Class 1: less than 0.55 g cm-3; Class 2: from 0.55 to 0.75 g cm-3; and Class 3: greater than 0.75 g cm-3) and joints bonded with two adhesives: polyvinyl acetate (PVA) and urea-formaldehyde (UF), under two different pressures: 6 and 12 kgf cm-2. Glued joints bonded with PVA adhesive presented higher shear strength than those bonded with UF adhesive. For percentage of wood failure, the PVA adhesive had the best performance, however, only Classes 1 and 2 reached the values required by ASTM 3110 standard. Glued joints from Class 3, bonded with UF adhesive, did not reach the values of solid wood. The gluing pressure of 12 kgf cm-2 was more efficient for Class 3, for both shear strength and percentage of wood failure.
Wood density; polyvinyl acetate; gluing pressure; shear strength; urea-formaldehyde
