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2025 Vol.41, Issue 2 Preview Page
Evaluation of Anchor Performance of Floating Offshore Wind Turbines in Sandy Soils

사질토 지반에서 부유식 해상풍력의 앵커성능 평가

Junho Lee1
,
Jo-Hyun Weon2
,
Tae-Min Oh3*
,
Charles P. Aubeny4
,
Song Qin5
이 준호1
,
원 조현2
,
오 태민3*
,
Charles P. Aubeny4
,
Song Qin5
1Member, CEO, Deep Anchor Solutions Inc.
2Graduate Student, Dept. of Civil and Environmental Engineering, Pusan National Univ.
3Member, Associate Prof., Dept. of Civil and Environmental Engineering, Pusan National Univ.
4Prof., Zachry Dept. of Civil and Environmental Engineering, Texas A&M Univ.
5Ph.D. Candidate, Zachry Dept. of Civil and Environmental Engineering, Texas A&M Univ.
1정회원, ㈜딥 앵커 솔루션즈 대표
2비회원, 부산대학교 사회환경시스템공학과 석사과정
3정회원, 부산대학교 사회환경시스템공학과 부교수
4비회원, 텍사스 A&M 대학교 토목환경공학과 교수
5비회원, 텍사스 A&M 대학교 토목환경공학과 박사과정
*Corresponding Author
30 April 2025. pp. 15-26
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Abstract

Offshore wind energy is essential for achieving carbon neutrality and responding to rapid climate change. It plays a crucial role in transitioning to sustainable energy. The movement of offshore wind projects into deeper waters has necessitated floating anchoring systems to overcome the limitations of fixed-bottom foundations. The foundations of floating offshore wind systems are installed in heterogeneous seabed conditions ranging from clay to sand. By selecting and applying anchors appropriate to the geotechnical conditions, we can substantially reduce the overall project cost and construction duration. This study tests three anchor designs—a deeply embedded ring anchor, suction caisson, and gravity anchor—on the sandy seabed of the offshore site of Ulsan, South Korea. The anchor efficiencies were assessed by analyzing the comparison of internal friction angle and embedment depth and the optimal design of anchors was suggested. Furthermore, the anchor installation and transport efficiency were evaluated under the assumed on-site conditions. The obtained data are expected to assist the estimations of the physical characteristics necessary for achieving the required bearing capacity of offshore foundations.

Keywords
Anchor design
Floating structure
Marine anchor
Offshore foundation
Ring anchor
Sandy soil

급격한 기후변화에 대응하고 탄소중립 목표를 달성하기 위해 해상풍력은 지속 가능한 에너지 전환에 필수적이다. 해상풍력 설치 부지의 수심이 증가함에 따라 기존의 고정식 기초 방식에서 부유식 앵커로의 전환이 요구된다. 부유식 해상풍력 기초는 점토에서 모래에 이르는 불균질한 지반에 시공된다. 이에 따라 지반 특성에 적합한 앵커의 선정 및 적용은 프로젝트의 비용 및 시공 기간에 영향을 미친다. 본 연구에서는 울산 해상 풍력 부지를 대상으로 사질토 지반에 적용 가능한 링 앵커(DERA), 석션 케이슨, 중력식 앵커로 나누어 설계를 수행하였다. 지반의 내부마찰각 및 관입깊이에 따라 해양기초의 효율성을 비교 분석하고 최적 설계값을 제시하였다. 또한 현장상황을 가정하여 앵커설치 및 운반효율성을 추가로 고찰하고자 하였다. 본 연구 결과는 해양기초에 필요 지지력 확보를 위해 요구되는 물리적 특성 추정을 위한 기초 자료로 활용될 수 있을 것으로 기대된다.

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 41
  • No :2
  • Pages :15-26
  • Received Date : 2025-03-07
  • Revised Date : 2025-04-22
  • Accepted Date : 2025-04-22
  • DOI :https://doi.org/10.7843/kgs.2025.41.2.15
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