CIVL439/W00D476 Use of Damage Model Spiral Grain problems dto be cabae nodel Juvenile Wood Compression Wood Material erties of () Strength property rallel to grain《) ression paralel to grain (f) 18 perpendicular to grain (fe) ng (e) 30 aralldl to grain（ 17CIVL439/WOOD476 17 Use of Damage Model • The damage model needs to be calibrated against DOL test data • The model parameters may be – Testing mode dependent – Spec es depe de t ies dependent – Size dependent – Etc • The calibrated model can be used n simulation study to evaluate the DOL behaviour of members subject to different random load histories Spiral Grain problems Juvenile Wood Compression Wood Material properties of wood … imagine a bundle of straws held together with el ti b d lastic bands • tension parallel to grain • compression parallel to grain • tension perpendicular to grain • compression perpendicular to grain • shear lignin cellulose fibres Design properties (approximate values, D (approximate values, D-fir No.1/2) fir No.1/2) Strength property Clear wood (MPa) Structural timber (MPa) Tension parallel to grain ( ft ) 20 6 Compression parallel to grain ( fc ) 18 14 Tension perpendicular to grain ( ftp ) 11 Compression perpendicular to grain ( fcp )88 Bending ( fb ) 30 10 Shear parallel to grain ( fv ) 11