부체형 중력식 기초의 개념설계

Concept Design of Floated Gravity Base Structures

  • 정민욱 (한국전력공사 전력연구원 에너지신산업연구소) ;
  • 강금석 (한국전력공사 전력연구원 에너지신산업연구소) ;
  • 조동호 (한국전력공사 전력연구원 에너지신산업연구소)
  • 투고 : 2018.05.18
  • 심사 : 2018.06.07
  • 발행 : 2018.06.30

초록

To reduce capital expenditures for offshore wind farms, new concepts of support structures have been suggested. Floated gravity base structures (GBSs), which use the buoyancy of the structure instead of using heavy lift vessels during the transport and installation process, are receiving much attention. The main difference between the floated GBS and conventional structures is a design based on floating stability. A floated GBS should maintain floating stability on its own until it is lowered onto the seabed. Therefore, the concept design of the floated GBS is derived to satisfy the minimum metacentric height of 0.75 m during the lowering operation in the installation. As floated GBSs are ballasted with sea water during installation, free surface effects and bulkheads are also taken into account. In regard to the model with a conical base, designs with minimum weights are presented by varying the batter angle of the base. In addition, the maximum load at the bottom of each design is analyzed to assess the bearing capacity of floated GBSs. Although the weight of the floated GBS is minimized at a batter angle of $0^{\circ}$, a batter angle larger than $30^{\circ}$ is recommended in consideration of the bearing capacity.

키워드

과제정보

연구 과제번호 : 해상풍력 터빈 일괄설치시스템 (MMB) 개발

연구 과제 주관 기관 : 한국전력공사

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