Determination of the elastic constants of Scots pine (Pinus sylvestris L.) wood by means of compression tests

• Exploratory study of elastic constants using strain gauges in compression tests.
• Tests on small clear specimens varying grain direction with respect to load applied.
• Deformations were measured by strain gauges bonded on specimen surfaces.
• Higher stiffness values obtained than are typical for softwood.

This presents an exploratory analysis of a method for the determination of elastic constants using strain gauges in compression tests. The elastic constants of Scots pine (Pinus sylvestris L.) wood from the “Valsaín” sawmill (Segovia, Spain) were obtained. Compression tests were performed on small clear specimens, varying grain direction with respect to the direction of the load applied. Deformations were measured by strain gauges bonded on specimen surfaces. The modulus of elasticity parallel to the grain was obtained for prismatic specimens measuring 20 × 20 × 60 mm. The modulus of elasticity perpendicular to the grain in both radial and tangential directions was obtained for 16 × 16 × 48 mm prismatic specimens and for 48 × 48 × 48 mm cubic specimens. The shear modulus in the LR, LT and TR (longitudinal (L), radial (R) and tangential (T)) planes was obtained for 16 × 16 × 48 mm prismatic specimens with the grain at 45°. Larger stiffness values than typical average values for softwood were obtained. It can be concluded that this method is suitable for determining the modulus of elasticity (longitudinal and transversal), and that the values obtained are greater than the average values for softwoods. On the other hand, the Poisson ratios obtained parallel to the grain were similar to values in the literature, though values for νRT and νTR were greater.