Softwood is frequently used as a structural part in the wood construction industry. To use softwood as a structural material, it must be strength graded in a grading class, e.g., by applying the visual strength grading rules (NS-INSTA 142). The wood is often used once in a linear way, from tree to waste (cradle to grave). Since not much is generally known around the circular use of wooden materials, the CircWOOD project wants to change this linear way of using wood in the industrial sector to a circular green shift in Norway.
In this topic, an assessment and evaluation are made of the existing visual strength grading rules of softwood by investigating whether there is potential to re-grade solid structural softwood and whether this grading can be carried out using the visual strength grading rules.
Keywords: CircWOOD, softwood, visual strength grading, re-use, re-grading
Authors
Lander Anraed
HOGENT University of Applied Sciences and Arts, Belgium
Andreas Stenstad
Norsk Treteknisk Institutt, Norway