Grading of Domestic Softwood $2{\times}6$ Structural Lumber by Non-destructive Test

비파괴 시험에 의한 국산 침엽수 $2{\times}6"$ 구조부재의 등급구분

  • Shim, Kug-Bo (Div. of Wood Engineering, Dept. of Forest Products at Korea Forest Research Institute) ;
  • Park, Jung-Hwan (Div. of Wood Engineering, Dept. of Forest Products at Korea Forest Research Institute) ;
  • Kim, Kwang-Mo (Div. of Wood Engineering, Dept. of Forest Products at Korea Forest Research Institute)
  • 심국보 (국립산림과학원 임산공학부 재료성능과) ;
  • 박정환 (국립산림과학원 임산공학부 재료성능과) ;
  • 김광모 (국립산림과학원 임산공학부 재료성능과)
  • Published : 2006.12.30

Abstract

This study was carried out to provide basic data for using domestic structural softwood lumber efficiently and ensuring structural safety of timber structures. The ratios (k-factor) between static and dynamic MOE measured by ultrasonic device for $2{\times}6$ domestic softwood structural lumber are 1.0602 for Korean red pine, 1.0013 for Korean white pine and 1.2320 for Japanese larch. In machine grade using nondestructive method, 76% of Korean red pine was classified into higher than E9 grade, 85% of Korean white pine was sorted into higher than E7 grade and 68% of Japanese larch was classified into higher than E11 grade. Correlation between MOE and MOR by static bending with k-factor from nondestructive method provide a possibility to predict bending strength and allowable stress of domestic softwood structural lumber.