Journal of the Korean Wood Science and Technology

The Korean Society of Wood Science & Technology (한국목재공학회)
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Feasibility of Non-Korean Standard Glulam Using a Lower Grade Lamina of Japanese cedar for Structural Use

  • Oh, Jung-Kwon (Department of Forest Sciences, Seoul National University) ;
  • Lee, Jun-Jae (Department of Forest Sciences, Seoul National University, Research Institute for Agriculture and Life Sciences)
  • Received : 2010.02.03
  • Accepted : 2010.03.02
  • Published : 2010.03.25
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Abstract

Japanese cedar has low density and poor mechanical performance. Manufacturing glue-laminated timber (glulam) is the best way to compensate for its poor mechanical performance. The Korean Standard (KS) confines outermost lamina of glulam to higher grade than E8, but the yield of higher than grade E8 from logs is only 6.5%. Therefore, the aim of this study is to investigate the possibility of non-Korean-Standard glulam in structural applications. Allowable stresses determined by both hand-calculation and Monte-Carlo simulation show a higher allowable stress than that of the KS-standard glulam of 6S-22B. In the Korean Standard (KS), knot characteristics are not taken into account. Japanese cedar has relatively small knots. We believe that the small knots in Japanese cedar contribute to a higher allowable stress than the KS-standard glulam would predict. The species classification of KS is required to be further subdivided into sub-species groups based on knot characteristics.

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References

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