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Structural Design Optimization of Lightweight Offshore Helidecks Using a Genetic Algorithm and AISC Standard Sections

유전 알고리듬 및 AISC 표준 단면을 사용한 경량화 헬리데크 구조 최적설계

  • Sim, Kichan (Department of Ocean Engineering, Korea Maritime and Ocean University) ;
  • Kim, Byungmo (Department of Convergence Study on the Ocean Science and Technology, Korea Maritime and Ocean University) ;
  • Kim, Chanyeong (Department of Ocean Engineering, Korea Maritime and Ocean University) ;
  • Ha, Seung-Hyun (Department of Ocean Engineering, Korea Maritime and Ocean University)
  • 심기찬 (한국해양대학교 해양공학과) ;
  • 김병모 (한국해양대학교 해양과학기술융합학과) ;
  • 김찬영 (한국해양대학교 해양공학과) ;
  • 하승현 (한국해양대학교 해양공학과)
  • Received : 2019.09.20
  • Accepted : 2019.09.28
  • Published : 2019.12.31

Abstract

A helideck is one of the essential structures in offshore platforms for the transportation of goods and operating personnel between land and offshore sites. As such, it should be carefully designed and installed for the safety of the offshore platform. In this study, a structural design optimization method for a lightweight offshore helideck is developed based on a genetic algorithm and an attainable design set concept. A helideck consists of several types of structural members such as plates, girders, stiffeners, trusses, and support elements, and the dimensions of these members are typically pre-defined by manufacturers. Therefore, design sets are defined by collecting the standard section data for these members from the American Institute of Steel Construction (AISC), and integer section labels are assigned as design variables in the genetic algorithm. The objective is to minimize the total weight of the offshore helideck while satisfying the maximum allowable stress criterion under various loading conditions including self-weight, wind direction, landing position, and landing condition. In addition, the unity check process is also utilized for additional verification of structural safety against buckling failure of the helideck.

Acknowledgement

Supported by : 한국연구재단

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