Strength Property of the Incised Larix (Larix kaempferi Carr.) Round Posts treated with CCA

인사이징 처리 낙엽송 CCA-방부원주목의 강도 성능 평가

  • Park, Jun-Chul (Department of Wood Science & Engineering, College of Forest & Environmental Sciences, Kangwon National University) ;
  • Kim, Sang-Woo (Department of Wood Science & Engineering, College of Forest & Environmental Sciences, Kangwon National University) ;
  • Ryu, Jae-Yun (Yeoju Wood Marketing Center, National Forestry Cooperatives Federation) ;
  • Hong, Soon-Il (Department of Wood Science & Engineering, College of Forest & Environmental Sciences, Kangwon National University)
  • 박준철 (강원대학교 산림환경과학대학 임산공학과) ;
  • 김상우 (강원대학교 산림환경과학대학 임산공학과) ;
  • 류재윤 (산림조합중앙회 여주목재유통센터) ;
  • 홍순일 (강원대학교 산림환경과학대학 임산공학과)
  • Received : 2007.10.10
  • Accepted : 2008.01.09
  • Published : 2008.05.25

Abstract

Strength of logs and round posts is compared and analyzed to estimate the strength of the incised Larix round posts treated with CCA in this paper. There is no significant difference in MOR of logs and round posts. However, in the incised Larix round posts treated with CCA MOE is decreased to about 9%, and there is 29% reduction in MOR as strength ratio is 0.71. When calculating the allowable bending stress of incised round type round posts, not in nominal 2-in timbers, an adjustment factor for MOE and bending strength is proposed as 0.91 and 0.71, respectively. Logs, round posts and the incised Larix round posts treated with CCA do not show significant difference in nail withdrawal load. There is almost no difference between incised Larix round posts treated with CCA and round posts in the shear strength of bolted joint. When calculating the allowable shear stress of bolted joint, it is conformed that considering the application of incising factor is not necessary.

본 연구에서는 인사이징 처리 낙엽송 방부 원주목의 강도 성능을 평가하기 위하여 원목, 원주목과 강도 성능을 비교 분석하였다. 원목과 원주목의 휨강도(MOR)는 큰 차이가 없었다. 인사이징 처리 방부 원주목은 휨탄성 계수(MOE)가 9% 감소하였고 휨강도는 원목에 대한 강도비 0.71로 약 29% 강도의 저하를 보였다. 일반적인 2인치 제재목이 아닌 원주 형태의 원주목을 이용한 휨허용응력 산정시 인사이징 방부처리 저감계수를 휨탄성계수는 0.91, 휨강도는 0.71로 적용해야 할 것으로 사료된다. 못뽑기 저항은 원목, 원주목, 방부 원주목 모두 큰 차이를 보이지 않았다. 볼트 접합부의 전단력은 인사이징 처리 방부 원주목과 원주목의 차이는 거의 나타나지 않았다. 볼트 접합부의 허용 전단 내력 산정에는 인사이징 저감 계수의 적용은 검토하지 않아도 됨을 확인할 수 있었다.

Keywords

References

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