Tensile strength and stiffness of low quality beech (Fagus sylvatica) sawn timber

This paper investigates the tensile strength and stiffness of low quality beech sawn timber. In addition, the influences of visual and physical characteristics of the beech boards on the mechanical performance were analysed. Visual characteristics like knots, pith or fibre deviation as well as density and dynamic modulus of elasticity were examined regarding their influence on the tensile strength and stiffness of the beech boards. The subsequent destructive testing was performed according to EN 408on 214 beech boards with two different cross sections. Correlation analyses regarding non-destructive and destructive parameters indicate possibilities and limits of strength grading in terms of beech sawn timber. This paper complements many investigations of the last years focusing mainly on the mechanical behaviour of middle and high quality beech sawn timber and glulam. As a large proportion of beech sawn timber is low quality material, a better understanding of its behaviour may lead to higher yield in combination with economic benefits as well as to more reliable strength grading and more efficient material use.