GREEN-GLUED LAMINATED BEAMS - HIGH PERFORMANCE AND ADDED VALUE

摘要

The work presented in this paper deals with the use of green gluing (also known as wet gluing) as a mean to overcome the difficulties in making use of side boards for structural applications. By manufacturing laminated beams from unseasoned side boards several advantages are obtained. Beams were manufactured from side boards of approximately 25 mm thickness. The board width was 120 mm. The boards were glued together with a 1-component polyurethane adhesive to form a beam cross-section of approximately 120×315 mm~2 . After curing, the beams were split into two halves, each approximately 55 mm wide. These 55×315 mm~2 beams were then dried in a conventional kiln dryer. Finally, the beams were planed to target size, 50×300 mm~2. Tests performed included beam bending tests for strength and stiffness, tests of the shape stability of the beams, tests of the integrity of the adhesive bond lines (delamination) and tests on the strength and fracture energy of the adhesive bond lines. The main results obtained show that there is a potential for the production of green-glued laminated beams with good technical performance.