PROPERTIES OF LAMINATED VENEER LUMBER MANUFACTURED FROM HEAT TREATED VENEER

The objective of this study was to determine and compare properties of laminated veneer lumber (LVL) panels manufactured from heat treated (212o C, 2h) and untreated pine veneer with melamine urea formaldehyde (MUF) adhesive. The results showed that, heat treatment considerably decreased all investigated physical properties of LVL. The reductions in density (D), moisture content (MC), and thickness swelling (TS) were 8.33%, 33.78% and 14.03%, respectively. The findings of this study demonstrated that heat treatment resulted in adverse effect on bending strength and hardness of LVL panels. Heat treatment caused a decrease in bending strength (MOR) by 31.85% and in hardness (HT) by 25.44%. However, modulus of elasticity (MOE) and compressive strength (CS) values of LVL panels were higher than those of untreated groups. Compressive strength and modulus of elasticity (MOE) of LVL panels made of heat treated veneer respectively were 11.17% and 7.46% higher than untreated LVLs