RECENTJ. (2019), 59:107-112 https://doi.org/10.31926/RECENT.2019.59.107 107 Properties of Resinous Wood Species Used in OSB Technology Bogdan IANCU Kronospan Brasov, Romania, iancu_bogdan28@yahoo.com Aurel LUNGULEASA Transilvania University of Brasov, Romania, lunga@unitbv.ro Elena MUŞAT Transilvania University of Brasov, Romania, david_elenabv@yahoo.com Cosmin SPIRCHEZ Transilvania University of Brasov, Romania, cosmin.spirchez@unitbv.ro Abstract The paper aims to discover the characteristics of softwood species used in the technology of oriented strand board. In this sense, the main physical-mechanical properties of three wood species (fir, spruce, and pine) were determined and obtained, based on the European standards. The physical properties of the solid wood will be compared with the characteristics of the oriented strand boards obtained from each resinous wood species, in a future work. From the analysis of wood properties, it was found that the softwood species are the best corresponding specie to this technology, because they have soft and light wood (due to their low density), and their higher mechanical strength will give very good mechanical strength of the boards. As a final conclusion of this work, it can be stated that the softwood species remain the basic species of the technology for the manufacture of oriented wood strand boards, due to their low density (thus good compressibility and compactness) and superior mechanical properties. Keywords OSB, wood specie, MOR, MOE, IB 1. Introduction The oriented strand boards (OSB) are composite boards obtained from a mixture of long chips (strand) with adhesive and hot pressed. These boards have taken a great advantage in the last period of time, due to the fact that it has replaced other expensive boards in its uses, especially in the constructions. At European level there is the ISO 16864: 2016 [1] standard, which explains the manufacturing requirements of OSB boards and divides these boards into four categories, depending on their properties. In the same sense, EN 300:2006 [2] divides the OSB boards into four categories, two for indoor boards and two for moisture resistant exterior boards. Within each category of OSB board, it is one category for small loads and another one for large loads (used in roof constructions and high strength beams). The OSB boards consist of three distinct layers, two for exterior and one for core. The faced chips are larger and are longitudinally oriented, and the core layer is made up of smaller chips, arranged perpendicular to the face layers. This makes the OSB have properties that are appropriate in both longitudinal and transverse directions, resembling plywood from this point of view. That is why the uses of OSB boards start from this property, resulting in applications in light constructions, overhangs, barracks, savannahs and wooden houses. Barnes 2000 [3] has developed a mathematical model with eight equations for predicting OSB properties according to the wood species used by eight factorial parameters, of which the most important were wood density, wood strength, resin content, dimension of strands and the angular deviation of strands. Beck et al. 2009 [4] compared two low density beach boards (aspen) and one medium density boards (birch), using strands with three lengths of 78, 105 and 142 mm and two thicknesses of 0.55 and 0.75 mm. The highest strengths (modulus of rupture-MOR, modulus of elasticity- MOE, compressive strength, stiffness and internal bond -IB) were obtained for birch, and long and thin strands. Bufalino (2015) [5] has investigated the mixing strands of three common species (Red cedar, Eucalyptus and pine), to obtain OSB boards. Research has shown that eucalyptus can replace pine wood, but Red cedar describes mechanical performance. Dixon et al 2017 [6] found a