Structural Safely Analysis of a Modified 1-2W Type Greenhouse Enhanced for Culturing Paprika

착색단고추 재배용 1-2W형 개조온실 구조의 안정성 검토

  • Suh, Won-Myung (Dept. of Agricultural Eng., Gyeongsang National Univ.(Institute of Agriculture and Life Science, GNU)) ;
  • Choi, Man-Kwon (Graduate school, Gyeongsang National Univ.) ;
  • Bae, Yong-Han (Graduate school, Gyeongsang National Univ.) ;
  • Lee, Jong-Won (Dept. of Agricultural civil Eng., Kyungpook National Univ.) ;
  • Yoon, Yong-Cheol (Dept. of Agricultural Eng., Gyeongsang National Univ.(Institute of Agriculture and Life Science, GNU))
  • 서원명 (경상대학교 지역환경기반공학과(농업생명과학연구원)) ;
  • 최만권 (경상대학학교 대학원) ;
  • 배용한 (경상대학학교 대학원) ;
  • 이종원 (경북대학교 농업토목공학과) ;
  • 윤용철 (경상대학교 지역환경기반공학과(농업생명과학연구원))
  • Published : 2008.09.30

Abstract

This study was performed to check the structural safety of modified 1-2W Greenhouses to be utilized fur growing Paprika. This type of greenhouse was derived from being remodeled by enhancing the column height of conventional 1-2W type greenhouses. According to the results of structural analysis performed by SAP-2000, there was not significant change in critical snow depth in spite of increasing the column height of 1.2 m by welding. But the critical wind velocities were shown to be $26.0\sim4l.0m/s$, which were $3\sim18%$ lower wind velocities compared with those critical velocities estimated for typical type of 1-2W greenhouse. Under the wind loads, those maximum section forces such as shear force, axial force, and bending moment, together with the deformed frame shape of strained greenhouse, were almost similar in both typical type and modified type. Maximum bending moment of column was found at eave's height of column on windward side. Under the snow loads, those maximum section forces such as shear farce, axial force, and bending moment, together with the deformed frame shape of strained greenhouse, were almost similar in both typical type and modified type. Maximum section forces except axial force was found at eave's height of column. Maximum axial force was found at inner column. Soil bearing capacity together with the total foundation resistance against wind upheaval was found to be consistently safe enough to resist to both wind load and snow load.

본 연구는 1-2W형 온실의 구조를 개조하여 착색단 고추 재배온실로 이용하고 있는 온실의 구조의 안정성을 검토하였다. SAP-2000에 의한 구조해석 결과 1-2W기본형 온실의 기둥을 1.2m높였을 경우, 구조물이 견딜 수 있는 한계적설심은 변화는 거의 없으나 한계풍속은 약 $26.0\sim41.0m/s$정도로서 기본형에 비하여 약 $3\sim18%$ 정도 감소하는 것으로 나타났다. 풍하중 작용시 변형도를 비롯하여 축방향력, 전단력, 휨모멘트 등의 최대단면력은 기본형이나 개조형에 관계없이 거의 유사한 경향으로 나타났으며, 최대단면력은 풍상측의 처마높이 부위에서 발생하는 것으로 나타났다. 설하중 작용시 변형도를 비롯하여 축방향력, 전단력, 휨모멘트 등의 최대단면력은 기본형이나 개조형에 관계없이 거의 유사한 경향으로 나타났으며, 축방향력을 제외한 최대단면력은 처마높이 부위에서 발생하였으며, 최대축방향력은 내측기둥에서 발생하였다. 한계적설심에 대한 내측기둥의 좌굴은 모두 안전한 것으로 나타났으며 세장비 또한 제한값 범위내에 들어 기본형 및 개조형 모두 만족하였다. 기초의 인발저항력과 지내력은 기본형과 개조형에 관계없이 모두 안전한 것으로 나타났다.

Keywords

References

  1. Kim, M. K. and S. W. Nam. 1995. Experimental studies on the structural safety of pipe-houses. J. Bio Env. 4(1):17-24(in Korean)
  2. Kim, K. W. 2007. Development of technology to reduce meteorological damage in agricultural structures. Symposium on measure to reduce meteorological damage in agricultural structures. Rural Development Administration. p. 148-150(in Korean)
  3. Korea Society of Steel Construction. 2003. Design basis of steel structure by allowable design method. I- 21-34(in Korean)
  4. Lee, S. G., 1995. Structural design of plastic greenhouses for prevention of meteorological disaster. Kyungpook National University:1-33(in Korean)
  5. Lee, S. K., J. W. Lee and H. W. Lee. 2004. Analysis of wind speed and snow depth of single-span plastic greenhouse by growing corp, Proceedings of the 2004 Annual Conference. KSAE:40(in Korean)
  6. Lee, S. G., H. W. Lee, J. W. Lee and C. S. Gwak. 2006. A study method for structural safety improvement of greenhouse by structural analysis, Proceedings of the 2006 Annual Conference. KSAE:21(in Korean)
  7. Park, C. W., S. G. Lee, J. W. Lee and H. W. Lee. 2005. Optimum design of greenhouse structures using continuous and discrete optimum algorithms. Proceedings of the 2005 Annual Conference. KSAE:33(in Korean)
  8. Ministry of Agriculture and Forestry. 2006. Production results of vegetable crop in 2005. 52-64(in Korean)
  9. Ministry of Agriculture and Forestry. 2006. Cultural state of floricultural crop in 2005. 3-13(in Korean)