Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
권호 표지
DOI QR코드

DOI QR Code

Evaluation of Structural Safety of Polyethylene Boats by Drop Test Method

낙하시험에 의한 폴리에틸렌 보트의 구조 안전성 평가

  • Lee, Sung-Riong (Dept. of Materials and Metallurgical Engineering, Kangwon Nat'l Univ.) ;
  • Kang, Gyung-Ju (Dept. of Mechanical Design Engineering, Kangwon Nat'l Univ.) ;
  • Cho, Seok-Swoo (Dept. of Mechanical Design Engineering, Kangwon Nat'l Univ.)
  • 이성룡 (강원대학교 금속재료공학과) ;
  • 강경주 (강원대학교 기계설계공학과) ;
  • 조석수 (강원대학교 기계설계공학과)
  • Received : 2017.03.08
  • Accepted : 2017.05.12
  • Published : 2017.05.31
Download PDF
⟨ Previous Next ⟩

Abstract

The structural safety of small craft, such as steel ships and FRP ships, can be estimated using the measurement test of the hull plate thickness or the longitudinal bending strength test. A polyethylene boat is made using inexpensive HDPE and can be mass produced. The structural safety of a polyethylene boat cannot be guaranteed because a polyethylene boat hull is notspecified in the KR technical rules. The inspection procedure of sailing yachts and pleasure boats and drop test method of ISO standard 12215-5 propose the structural strength required for small crafts as the drop test height. Therefore, in this study, the drop test of a polyethylene boat hull was carried out based on the inspection procedure of a sailing yacht and pleasure boat and the drop test method of ISO standard 12215-5. The drop load was acquired by the drop acceleration ofa boat hull. Structural analysis and safety of a polyethylene boat were performed by the drop load and allowable stress criteria. The calculation results of the hull plate thickness by structural design specification of ISO standard 12215-5 showed that polyethylene boat hull was more than two times thicker than a steel ship hull and the boat hull determined by the inspection procedure of sailing yacht and pleasure boat and drop test method of ISO standard 12215-5 was more than 1.2 times thicker than the boat hull determined by structural design specification of ISO standard 12215-5. Therefore, inspection procedure of sailing yachts and pleasure boats and drop test method of ISO standard 12215-5 was much more conservative than the structural design specification of ISO standard 12215-5 and could be used as the structural design method of a polyethylene boat.

강선이나 강화플라스틱선 등의 선박 재료는 선박안전법에 규정된 규격재료를 사용하는 경우로서 판두께 측정시험이나 종굽힘강도시험을 통하여 제작 선체의 구조 안전성을 쉽게 확인할 수 있다. 한편, 염가의 폴리에틸렌 등과 같은 비규격재료를 선체 전장이 짧은 플레저 보트의 선체로 사용하는 경우 역학적 특성을 파악하기 쉬워 선체 설계를 수행하기에 매우 유리하고, 대량 생산 시스템을 갖추는 경우 제작 비용이 낮아 해당 제품의 가격 경쟁력을 가질 수 있다. 그러나 폴리에틸렌 선체의 경우 비규격재료를 사용함에 따라 기존의 소형선체에 대한 종굽힘강도시험을 이용하여 선체의 구조 안전성을 평가할 수 없다. 이러한 문제점을 해결하기 위하여 본 연구에서는 플레저 보트의 낙하시험 표준절차인 플레저 보트 검사 기준과 ISO 12215-5를 기초로 폴리에틸렌 선체에 대한 낙하시험을 수행한 후 이것을 기초로 정적구조해석을 수행하여 비규격재료로 개발된 선체의 구조 안전성을 확인함으로서 플레저 보트 검사 기준과 ISO 12215-5의 낙하시험방법이 선체 구조설계에 이용될 수 있음을 보였다.

Keywords

References

  1. Nian-Zhong Chena and C. Guedes Soares, "Longitudinal strength analysis of ship hulls of composite materials under sagging moments", Composite Structures, vol. 77, pp. 36-44, 2.007. DOI: https://doi.org/10.1016/j.compstruct.2005.06.002
  2. B. K. Hong, "A Study on the standard of ship hull construction for aluminium alloys fishing boats", The Korean Society for Fisheries and Marine Sciences Education, vol. 12, no. 1, pp. 22-88, 2000.
  3. N. Z. Chen, C. G. Soares, "Reliability assessment for ultimate longitudinal strength of ship hulls in composite materials", Probabilistic Engineering Mechanics, vol. 22, no. 4, pp. 330-342, 2007. DOI: https://doi.org/10.1016/j.probengmech.2007.05.001
  4. B. Y. Kang, Build Wooden canoe by Myself, Mannam Press, pp. 103-108, 2007.
  5. C. K. Park, M. G. Kim, S. S. Cho, "A study on manufacturing and structural design of leisure canoe", Proceedings of the KSME(The Korean Society of Mechanical Engineers) 2010 Spring annual meeting, pp. 403-404, 2010.
  6. A. D. Drozdov, J. C. Christiansen, "Modelling the viscoplastic response of polyethylene in uniaxial loading-unloading tests", Mechanics research communications, vol. 30, pp. 431-442, 2003. DOI: https://doi.org/10.1016/S0093-6413(03)00040-5
  7. X. Q. Wang, N. Brown, "The stress and strain fields in the neighbourhood of a notch in polyethylene", Polymer, vol. 30, pp. 456-1461, 1989. DOI: https://doi.org/10.1016/0032-3861(89)90215-2
  8. S. S. Cho "Structural design of polyethylene boat by longitudinal bending strength test method," The Korean Society of Mechanical Engineers, 2015 spring and fall annual meeting, pp. 141-142, 2015.
  9. Ministry of Oceans and Fisheries (Korean), Marine leisure ships guideline, Ministry of Oceans and Fisheries, pp. 36-38, 2013 (Korean).
  10. ISO 12215-5, Small craft-Hull construction and scantlings-Part 5 : Design pressures for monohulls, design stresses, scantlings determination, pp. 49-51, ISO, 2008.
  11. S. S. Cho, "A Study on Hull Form Development of Polyethylene Boat," Journal of the Korea Academia-Industrial cooperation Society. vol. 14, no. 10 pp. 4726-4732, 2013. DOI: http://dx.doi.org/10.5762/KAIS.2013.14.10.4726
  12. W. M. Kwak, A study on the Hull Product Design of Polyethylene Boat, pp. 45-48, Master thesis, Graduate School of Industry & Science, Kangwon National University, 2013.
  13. KS, Testing method for tensile creep of plastics, pp. 1-13, KS, 2012.
  14. KBC 2017, South Korean standard for steel building structures, MOLIT(Ministry of land, infrastructure and transport in South Korea), pp. 41-60, 2017.
  15. EN 1317, Road restraint systems, CEN (the European Committee for Standardization), pp. 23-45, 2010.
  16. Y. G. Bae, S. L. Lee, "Ship Collision Risk Assessment and Sensitivity Analysis for Sea-crossing Bridges", Journal of the Korean Society of Civil Engineers, vol. 33, no. 5, pp. 1753-1763, 2013. DOI: https://doi.org/10.12652/Ksce.2013.33.5.1753
  17. H. J. Lee, S. H. Yun, T. H. Park, "Ship Collision Damage Analysis of Bridge Structure," Proceedings of the KCI 2010 spring meeting, pp. 593-594, KCI (Korea concrete institute), 2010.
  18. ISO 12215-5, Small craft-Hull construction and scantlings-Part 5 : Design pressures for monohulls, design stresses, scantlings determination, pp. 28-31, ISO, 2008.
  19. ISO 12215-5, Small craft-Hull construction and scantlings-Part 5 : Design pressures for monohulls, design stresses, scantlings determination, pp. 52-79, ISO, 2008.
  20. W. M. Kwak, A study on hull product design of polyethylene boat, pp. 73-81, Master thesis, Graduate School of Industry & Science, Kangwon National University, 2013.
  21. S. S. Cho, "Study of Structural Design of Polyethylene Pleasure Boat," KSME(A), vol. 36, no. 12, pp. 1551-1561, 2012. DOI: https://doi.org/10.3795/ksme-a.2012.36.12.1551
  22. N. E. Dowling, Mechanical behavior of materials, pp. 112-114, Prentice-Hall Inc., 1999.