Using computed tomography data for finite element models of wood boards

Abstract

A procedure is presented to generate 3D FE models of timber boards based on CT scans. The boards were tested in four-point bending tests until failure and the local displacement in the pure bending zone was recorded. The CT scans were treated as 3D images and image processing methods were used to reconstruct the board, the knots and the pith. A new procedure to reconstruct the fibre deviations around knots by accounting for image gradient information was used. A quadratic tetrahedral mesh was generated for the region of the board which was under pure bending in the tests. The fibre directions and the stiffness tensor, scaled by the local density, were transferred into each integration point of the mesh and the bending test was replicated. Preliminary results show that the procedure is able to realistically predict the observed local stiffness of the boards. Further development of the procedure is required to account for dead knots and to extend the procedure for indicating strength and predicting failure.