Mechanical properties of structural-Grade oriented strand board

From the viewpoint of the structural engineer, the mechanical properties of materials are the primary data required in design and grading Standards. In this regard, tests of oriented strand board (OSB) in Europe and America have enabled a review of its mechanical properties. The tests results show that the order of increasing characteristic strength and stiffness in the major axis is roughly as follows: planar shear, panel shear, tension, compression, bending. The ranges of the ratio of property in major axis to property in the minor axis are 1.4-3.0 for bending, 0.9-1.7 for tension and compression, and 0.8-1.2 for panel and planar shears. For a given grade of panel, the characteristic punching shear capacity per unit thickness (25-mm diameter load applicator) appears to be roughly constant. Unlike the other strength properties, a single value of compression strength perpendicular to the plane of OSB panels, normally the near-minimum value, is conservatively adopted as the characteristic bearing strength of OSB panels. The long-term property levels vary with design Standard. While extensive data are available for the bending, axial and to a lesser extent shear, bearing and creep properties, data for Poisson's ratios are scarce.