Zur Orthotropie der physikalisch-mechanischen Eigenschaften von Rotbuchenholz

The orthotropic behaviour of the physical-mechanical properties of European beech wood

Hardwood is tried to be increasingly established in building industry in order to realise a larger material output and to take at once into account the structural advantage of the improved mechanical properties of hardwood in comparison to softwood. For the partially required calculations therefore of stress and strain in boards and glued-laminated timbers (for example prognosis of potential delamination and aging of glued joints), it is essential to know the directional specific values of wood in the directions longitudinal, radial and tangential. This concerns the elastic specific values (YOUNG's modulus, shear modulus, POISSON's ratio), the specific values of strength (tension, compression, bending, shear) and also these of mass and heat flux (diffusion coefficient, thermal conductivity). Additionally, it is necessary to know the dependencies from moisture and duration for all specific values. Selected parameters for European beech wood will be presented concerning the dependencies of YOUNG's modulus, shear modulus, POISSON's ratio, thermal conductivity and diffusion coefficient from direction and moisture. The results summarize investigations on this topic realised at the Wood Physics Group of ETH Zurich.