Properties Evaluation by Thickness and Type of Oriented Strand Boards Manufactured in Continuous Press Line

Oriented strand boards (OSB) are widely used in construction to replace plywood. There are four types of boards (OSB/1, OSB/2, OSB/3, and OSB/4) that are used, depending on the conditions for use. This study aimed to evaluate the physical and mechanical performance of these types of boards having the following thicknesses: 10 mm, 11 mm, 18 mm, and 22 mm. The boards were industrially manufactured using a continuous press line. The results showed that the compression ratio increased with decreasing of the wood strands' densities, from 1.3 (OSB/1) to 1.1 (OSB/3). The thickness swelling values were lower for OSB/3 and OSB/2 with 35% and 14%, respectively, when compared to OSB/1. For these boards, a slight increase in adhesive content and a lower speed of pressing line was set, considering that they were designated for exterior use. An increase in density with 7.6% led to an increase of approximately 19% of the modulus of rupture (MOR), when comparing OSB 10 mm with OSB 22 mm. Improvements of 27% to 22% MOR and 13% to 10% modulus of elasticity (MOE) for OSB/3 and OSB/2 compared to OSB/1 were found. The internal bond (IB) values were approximately 32% higher for OSB/3 than those reached by OSB/1, and the thinner boards registered 25% higher IB values even after the boiling test, compared to the thicker ones.