Analys av sprickdetektion vid automatisk avsyning av granvirke : med avseende på sprickors bredd, längd och djup

by Andreasson, Robert; Jansson, Pontus

Abstract (Summary)
This degree project aims to examine any connections between superficial cracks in timber, in terms of dimensions and characteristics, a matter insufficiently addressed by today's visual grading systems. The projects emphasis lies within the practical studies of cracks, characteristics and dimensions, within the acquired samples. In essence, the survey set out to determine superficial dimensions, depth, type and position of cracks by using a visual grading system (WoodEye), and by comparing the results by manually measuring a number of crosscutted cracks. The material used in the experiments and which formed the basis for subsequent analysis has been of such a nature that it could be equated with structural timber normally defined under the European Standard EN 14081-1.The project has encompassed the analysis of 568 examples of cracks consisting of 8 various types of cracks. By obtained results it has established that the greatest and smallest width is shown in resin pockets, respective side cracks, the greatest and least average height shown in sapwood cracks, respective resin pockets, and that the greatest average depth shown in cracks occurred from felling or hurricanes. From analysis of the cracks breadth and height in relation to depth no clear connection can be established.
Bibliographical Information:


School:Växjö universitet

School Location:Sweden

Source Type:Master's Thesis

Keywords:cracks sawn timber scanning sorting spruce structural visual grading woodeye crack


Date of Publication:08/13/2008

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