Characterisation of Irish-grown Scots pine timber for structural applications

Abstract

There is very little knowledge on the timber quality of the native Scots pine grown in Ireland, and its potential to produce timber for structural applications. This paper studied the mechanical performance in tension and bending of 100 specimens with 100mm x 44mm cross-section. Pairs of specimens were established based on the dynamic modulus of elasticity and density, with one specimen destructively tested in tension, and the other in bending. Grade determining wood properties of modulus of elasticity, strength and density were determined in accordance with EN408, with adjustment to reference moisture content and depth according to EN384. The two sets were graded to the tension and bending strength classes defined in EN338. Results showed that Irish-grown Scots pine can produce timber yields above 96% of C20 class. In tension, yields above 90% can be obtained for T11 and T12 classes. These values are slightly higher than those for Sitka spruce in Ireland and therefore show the potential of Irish grown Scots pine for timber production. The study showed that the model given in the European standards to estimate tension strength values from bending strength values underpredicts the values obtained for the Irish Scots pine here studied. A new model describing the relationship between the tension and bending strength properties was developed using the Irish dataset.