Effect of density and some of the production parameters on bending strength of laminated window profiles

Laminated lumber represents design alternatives for various applications including window profiles. The objective of this study is to investigate influence of species, density of wood, resin type, cross-section configuration, and member thickness on strength properties of window profiles manufactured from laminated lumber. Laminated profiles were manufactured from Scotch pine (Pinus sylvestris) and red pine (Pinus brutia) with different density levels and two cross section configurations using urea formaldehyde and polyvinyl acetate (PVAc) resins. It was found that Scotch pine with tangential–radial–tangential cross-section configuration using different layer thickness had the highest bending strength with an average of 99.22 N/mm2. The highest correlation coefficient values between MOR and density were 0.83 and 0.78 for the samples glued using PVAc of Scotch pine and red pine, respectively. Based on the statistical analyses it was also determined that cross-section configuration, and laminate thickness influenced overall bending strength of the specimens.