Material parameters of European spruce for tensile-shear fracture modeling

In this work, we present the results from an experimental campaign on solid and glued laminated timber made of European spruce (Picea abies) with 10.5 mm or 45 mm thick lamellas. We conducted off-axis tension and compression tests, shear block test, and compact tension test. The main purpose of the study was to obtain a consistent set of material parameters suitable for the calibration of a material model capable of capturing complex timber behavior, i.e. both linear and non-linear response together with respective fracture pattern, under various combinations of tension, shear, and compression. Elastic parameters and strengths parallel and perpendicular to the grain were retrieved from off-axis tension and compression tests. The traction-separation relation and fracture energy for the crack parallel to the grain was obtained by inverse analysis of compact tension test. The results capture the complexity of timber fracture and provide data for numerical simulations.