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Research Paper

Evaluation of Structural Response of Cylindrical Structures Based on 2D Wave-Tank Test Due to Wave Impact

파랑충격력에 의한 원형실린더구조물의 구조응답평가

Kangsu Lee1*
Yoon-Jin Ha2
Bo Woo Nam3
Kyong-Hwan Kim4
Sa Young Hong5
이 강수1*
하 윤진2
남 보우3
김 경환4
홍 사영5
1Principal Researcher, Korea Research Institute of Ships & Ocean Engineering, Professor, University of Science & Technology
2Senior Researcher, Korea Research Institute of Ships & Ocean Engineering
3Assistant Professor, Department of Naval Architecture & Ocean Engineering, Seoul National University
4Principal Researcher, Korea Research Institute of Ships & Ocean Engineering, Professor, University of Science & Technology
5Principal Researcher, Korea Research Institute of Ships & Ocean Engineering, Professor, University of Science & Technology
1선박해양플랜트연구소 해양플랜트에너지연구본부 책임연구원, 과학기술연합대학원대학교(UST) 선박해양공학전공 교수
2선박해양플랜트연구소 해양플랜트에너지연구본부 선임연구원
3서울대학교 조선해양공학과 조교수
4선박해양플랜트연구소 해양플랜트에너지연구본부 책임연구원, 과학기술연합대학원대학교(UST) 선박해양공학전공 교수
5선박해양플랜트연구소 해양플랜트에너지연구본부 책임연구원, 과학기술연합대학원대학교(UST) 선박해양공학전공 교수
*Corresponding Author
October 2020. pp. 287-296
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Abstract

본 연구에서는 2D 조파수조를 통해 수행된 모형시험결과를 기반으로 원형실린더에 분포하는 파랑충격압력을 시간에 따라 계측하고 이를 CFD해석 결과와 비교하였다. 전산유체역학 해석을 통해 파랑충격력에 직접평가법에 관한 효용성을 확인할 수 있었고, 실험으로부터 구한 파랑충격 시계열 데이터를 그대로 원형단면을 갖는 실제 해양구조물의 부재에 적용하였다. 실린더에 분포하는 변위 및 응력의 특성과 특이점이 바뀌는 것을 확인하였고 실제 시계열을 적용하는 것이 해양구조물의 강도평가를 보다 정확하게 평가할 수 있음을 확인할 수 있었다. 또한, 선수부에 요구되는 외판의 최소선급규정에 따른 두께 경험식들을 분석하여 적용하고자 하였다. 동일한 재료 물성치를 갖는 강재에 관해 선수외판에 요구되는 구조물의 최소두께와 원형단면 부재에 요구되는 최소두께를 비교·분석하였고 이를 통해 NORSOK standard에 제시되어 있는 구조물의 손상기준을 활용하여 허용 두께치를 추정하고자 하였다. 특히 해양구조물의 갑판충격력(wave in deck)의 경우 이와 관련된 경험식이나 최소두께 요구사항들이 정립되어 있지 않기 때문에 본 연구를 통해 파랑충격력에 따라 요구되는 판재의 최소두께를 제안하고자 하였다.

키워드
파랑충격
2차원 수조시험
실린더구조물
구조응답
구조손상

The wave-impact load on offshore structures can be divided into green-water and wave-slamming impact loads. These wave impact loads are known to have strong nonlinear characteristics. Although the wave impact loads are dealt with in the current classification rules in the shipping industry, their strong nonlinear characteristics are not considered in detail. Therefore, to investigate these characteristics, wave- impact loads induced by a breaking wave on a circular cylinder were analyzed. A model test was carried out to measure the wave-impact loads due to breaking waves in a two-dimensional (2D) wave tank. To generate a breaking wave, the focusing wave method was applied. A series of 2D tank tests under a horizontal wave impact was carried out to investigate the structural responses of the cylindrical structure, which were obtained from the measured model test data. According to the results, we proposed a structural damage-estimation procedure of an offshore tubular member due to a wave impact load. Furthermore, a recommended wave-impact load is suggested that considers the minimum required thickness of each member. From the experimental results, we found that the required minimum thickness is dependent on the impact pressure located in a three-dimensional space on the surface of a tubular member.

Keywords
wave impact
2D wave tank test
cylindrical structure
structural response
structural damage
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Information
  • Publisher :Computational Structural Engineering Institute of Korea
  • Publisher(Ko) :한국전산구조공학회
  • Journal Title :Journal of the Computational Structural Engineering Institute of Korea
  • Journal Title(Ko) :한국전산구조공학회 논문집
  • Volume : 33
  • No :5
  • Pages :287-296
  • Received Date :2020. 04. 22
  • Revised Date :2020. 06. 09
  • Accepted Date : 2020. 06. 29
  • DOI :https://doi.org/10.7734/COSEIK.2020.33.5.287
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