In this study, the stress distribution and stress concentration factor (SCF) of a generic notched wood piece and ASTM D 143:14 notched shear block specimen were analysed. A 2D plane stress finite element model with linear elastic behaviour was assumed for the bulk material and a predefined potential crack path and cohesive behaviour of the crack surfaces were considered. Wood was considered an orthotropic material with transversal isotropy. In the notched wood pieces, the shear stress distribution along the shear plane and the SCF when varying the ratio l/t (length of the heel/depth of the notch) was obtained. The shear stress distribution is not uniform in any situation, approaching a slightly triangular shape. The shear stress concentration increases when l/t is greater and for l/t > 8 failure occurs due to crack progression. The SCF can be brought fairly close to the natural logarithm of l/t. In the ASTM D 143:14 notched shear block specimen, shear stress distribution only remains a constant value in the central part of the shear plane, while the SCF is greater than 2.
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