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2024 Vol.37, Issue 6 Preview Page

Research Paper

Quasi-Dynamic Analysis Model of Mooring Lines Using Response Surface Approximation Method

응답면 근사 기법을 적용한 계류선의 준동적 해석 모델

Wonsuk Park1*
박 원석1*
1Professor, Department of Civil Engineering, Mokpo National University, Muan, 58554, Korea
1국립목포대학교 토목공학과 교수
*Corresponding Author
31 December 2024. pp. 425-432
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Abstract

This paper proposes a quasi-dynamic mooring line analysis method that accounts for dynamic effects when calculating the tension on the mooring lines of floating structures. The quasi-dynamic approach calculates the static tension of the mooring line at each time step using the elastic catenary solution and then applies a quasi-dynamic tension coefficient to account for the drag and inertial forces due to velocity and acceleration. To improve the computational efficiency of determining the static elastic catenary solution, a response surface method was employed. Additionally, a new technique was introduced to determine the quasi-dynamic tension coefficient by combining the dynamic coefficients in the horizontal and vertical directions. The proposed model was validated through a motion analysis of a moored barge by comparing the results of the dynamic, quasi-static, and quasi-dynamic models under various wave conditions. The quasi-dynamic model demonstrated tension responses similar to the responses of the dynamic model, particularly in the frequency ranges where the dynamic effects on the mooring line are significant.

Keywords
floating structures
dynamic mooring analysis
quasi-dynamic analysis
response surface approximation

이 논문에서는 부유식 구조체의 계류선에 작용하는 장력을 계산함에 있어서 동적 효과를 고려할 수 있는 준동적 계류선 해석 방법을 제안하였다. 준동적 계류선 해석 방법은 매 시간 단계에서 계류선의 탄성 현수선 해석해에 기반한 정적 장력을 계산한 후, 준동적 장력 계수를 적용해 속도와 가속도에 따른 항력 및 관성력의 영향을 반영하는 방법이다. 제안하는 방법은 정적 탄성 현수선 해석해를 구할 때 계산 효율성을 높이기 위해 응답면 기법을 도입하고, 수평 및 수직 방향의 동적 계수를 결합하여 준동적 장력 계수를 결정하는 새로운 방법을 제안하였다. 제안된 모델은 계류된 바지선의 운동 해석을 통해 검증하였으며, 다양한 파 조건에서 동적, 준정적, 준동적 모델을 비교한 결과, 제안된 준동적 모델은 상대적으로 계류선의 동적 효과가 큰 주파수 대역에서 동적 모델과 유사한 장력 응답을 도출할 수 있음을 확인하였다.

키워드
부유식 구조체
계류선 동적 해석
준동적 해석
응답면 기법
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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 : 37
  • No :6
  • Pages :425-432
  • Received Date : 2024-11-20
  • Revised Date : 2024-12-05
  • Accepted Date : 2024-12-09
  • DOI :https://doi.org/10.7734/COSEIK.2024.37.6.425
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