Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Bearing Capacity Evaluation of Hybrid Suction Bucket Foundations on Clay Under Horizontal Loads Using a Centrifuge

원심모형실험을 활용한 점토지반에 설치된 하이브리드 석션 버켓기초의 수평방향 지지력 평가

  • Kim, Jae-Hyun (Dept. of Civil Engrg., The College of Art, Culture and Engrg., Kangwon National Univ.) ;
  • Lee, Cheol-Ju (Dept. of Civil Engrg., The College of Art, Culture and Engrg., Kangwon National University) ;
  • Shin, Hee Jeong (Dong Myeong Engrg. Consultants) ;
  • Kim, Seong Hwan (Research Department, Dong Myeong Engrg. Consultants) ;
  • Goo, Jeong Min (Research Department, Dong Myeong Engrg. Consultants) ;
  • Jung, Chung Yeol (Research Department, Dong Myeong Engrg. Consultants) ;
  • Jeon, Young-Jin (Institute of Industrial Technology, Kangwon National Univ.)
  • 김재현 (강원대학교 문화예술.공과대학 건축토목환경공학부 토목공학전공) ;
  • 이철주 (강원대학교 문화예술.공과대학 건축토목환경공학부 토목공학전공) ;
  • 신희정 (동명기술공단) ;
  • 김성환 (동명기술공단 부설연구소) ;
  • 구정민 (동명기술공단 부설연구소) ;
  • 정충열 (동명기술공단 부설연구소) ;
  • 전영진 (강원대학교 산업기술연구소)
  • Received : 2023.11.13
  • Accepted : 2023.11.23
  • Published : 2023.12.31
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Abstract

Suction buckets are feasible options for offshore foundations to support subsea structures in deep water, enabling suction-induced installation by pumps. Recently, hybrid suction bucket foundations that combine single or multiple suction buckets with a mat foundation have been considered. The foundations effectively increase the load capacity while reducing construction costs. However, there is still insufficient experimental validation of hybrid suction bucket foundations regarding their bearing capacity. Furthermore, research on the horizontal load capacity under low vertical and moment loads is inadequate. In this study, we investigate the feasibility of using a hybrid suction bucket foundation for subsea installations in clay. We considered two types of hybrid suction bucket foundations: a circular mat with a single suction bucket and a square mat with multiple buckets. Centrifuge tests were performed to understand the hybrid suction bucket foundation characteristics under horizontal loads and their corresponding bearing capacity. Particularly, we verified the effect of the mat foundation and bucket embedment depth on the horizontal bearing mechanism and capacities. Results confirmed that the hybrid suction bucket foundation outperforms the single suction bucket.

석션 버켓(suction bucket)은 해양 구조물 지지를 위해 사용되는 기초구조물 중 하나로 펌프를 이용해 빠르게 기초 시공이 가능한 장점이 있다. 최근 기초 지지력을 효과적으로 증가시키고 건설 비용을 절감하기 위해 단일 석션 버켓이나 다수의 석션 버켓이 매트기초와 결합된 하이브리드 석션 버켓기초(hybrid suction bucket foundation)가 제안되었다. 하지만 현재까지 수중구조물과 같이 작은 수직하중(자중)과 모멘트 하중 조건에서 수평하중에 대한 하이브리드 석션 버켓기초의 저항 메커니즘과 지지력에 관한 실험적 연구가 부족한 실정이다. 따라서, 본 연구에서는 점토지반에 설치된 하이브리드 석션 버켓기초의 수평방향 저항 메커니즘과 지지력을 평가하기 위해 하중재하시스템을 구축하고 원심모형실험을 수행하였다. 본 연구에서는 원형매트와 단일 버켓이 결합된 하이브리드 석션 버켓기초와 사각형 매트와 4개의 버켓기초가 결합된 하이브리드 그룹 석션 버켓기초를 대상으로 하였다. 본 연구를 통해 매트기초와 석션 버켓기초의 스커트(skirt) 길이가 수평방향 지지력 증진에 미치는 영향을 실험적으로 평가하였다. 그 결과, 작은 수직하중과 모멘트 하중조건에서 하이브리드 석션 버켓기초의 매트와 버켓기초 스커트가 기초의 수평방향 지지력 증진에 효과가 있음을 확인하였다.

Keywords

Acknowledgement

본 연구는 해양수산부 "해저공간 창출 및 활용 기술 개발(과제번호 20220364)" 사업의 연구비 지원으로 수행되었습니다.

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