Grading by non-destructive techniques and assessment of the mechanical properties of large cross section coniferous sawn timber for structural use

摘要

This paper is the result of a research project based on large cross section sawn timber. The sample studied consisted of 395 structural pieces of three different coniferous species with a Spanish source.Based on the authors' findings, the paper concludes that for gross cross-section coniferous sawn timber strong relationships exist between the dynamic modulus of elasticity obtained by longitudinal vibration frequency and penetration depth, and mechanical properties. Furthermore, there are statistically significant differences for the variables studied according to species; the qualitative factor "species" is therefore used as a predictor to perform multiple regression analyses. NDT such as vibration analysis and penetration depth evaluation have become widely acceptable. This is because they are accurate, portable, cheap and easy to apply.