CT based modelling to predict the strength of timber before sawing
Current strength grading technologies used in sawmills only exploit a small fraction of the potential strength of sawn timber. The adoption of X-ray computed tomography (CT) scanners in some sawmills have made it possible to measure the inner structure of logs to optimise sawing. The abundant data generated during CT scanning provides a valuable resource on which numerical models could be based to analyse the timber.
The goal of this project is to develop a reliable method to generate 3D finite element (FE) models based on CT scans of timber to simulate its mechanical behaviour under load and predict stiffness and strength. The project also includes the reconstruction of the local fibre orientations and material stiffness in each point of the scanned volume, and most importantly around knots since it is a prerequisite for high-fidelity FE models of timber. Initially, the project focuses on CT scans of dried sawn timber. In the future, the method can be adapted for green sawn timber and ultimately for green logs, where “virtual” boards inside logs could be analysed for strength in a simulation already before sawing.
During the project, a reconstruction algorithm has been developed (see Figure) which was able to predict the mechanical properties of Norway spruce sawn timber with high accuracy [1].
[1] Huber, J. A. J., Ekevad, M., Broman, O., Oja, J., Hansson, L. (2021): A Method for Generating Finite Element Models of Wood Boards from X-Ray Computed Tomography Scans. Computers & Structures, 240, 106702. DOI: https://doi.org/10.1016/j.compstruc.2021.106702 External link.
Project information
Subject: CT-based FE-modelling
Time span project: December 2021 – November 2022
Contact
Johannes Huber
- Associate Senior Lecturer
- 0910-585337
- johannes.huber@ltu.se
- Johannes Huber
Updated: