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2019 Vol.35, Issue 12 Preview Page

Research Article

Evaluation of the Moment Bearing Capacity of Offshore Bucket Platforms in Sand

사질토 지반에 설치된 해상 버켓작업대의 모멘트 지지력 산정

Vicent Ssenyondo1
,
Kyo-Young Gu2
,
Sung-Ryul Kim3*
Ssenyondo Vicent1
,
구 교영2
,
김 성렬3*
1Ph.D. Student, Dept. of Civil Engrg., Dong-A Univ.
2Member, Ph.D. Student, Dept. of Civil and Environmental Eng., Seoul National Univ.
3Member, Associate Prof., Dept. of Civil and Environmental Eng., Seoul National Univ.
1비회원, 동아대학교 토목공학과 박사과정
2정회원, 서울대학교 건설환경공학부 박사과정
3정회원, 서울대학교 건설환경공학부 부교수
* Corresponding Author
31 December 2019. pp. 101-109
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Abstract

버켓작업대는 새롭게 개발되는 해상 구조물로서 교량기초 등의 시공을 위한 장비 및 인력의 임시 작업공간을 제공하는데 이용된다. 버켓작업대는 작업하중의 편심, 파도 및 바람의 수평하중 등에 의해 모멘트 하중이 작용한다. 그러므로, 본 연구에서는 3차원 유한요소 수치해석을 수행하여 버켓작업대의 모멘트 지지력을 산정하였다. 우선, 버켓에 대한 현장실험 결과와 비교하여 수치모델링의 적용성을 분석하였다. 그리고, 흙의 밀도, 버켓의 직경과 지중 근입깊이 등 다양한 조건에 대한 변수연구를 수행하였다. 지반조건은 균질한 사질토 조건을 적용하였으며 모멘트 하중은 지지대 상판의 중앙지점 회전각을 증가시켜면서 재하하였다. 모멘트-회전 해석결과로부터 모멘트 지지력을 산정한 결과 지지력이 버켓의 직경과 근입깊이에 영향을 받는 것으로 나타났다. 최종적으로 해석결과를 종합하여 버켓작업대의 예비설계를 위한 모멘트 지지력 예측식을 제안하였다.

The bucket platform is a new structure suitable for construction of offshore bridge foundations and providing the temporary support for equipments and labour. The platform can be subjected to moment loading due to the eccentric loading or the horizontal load by wave and wind. Therefore, a three dimensional finite element analysis was performed to evaluate the moment bearing capacity of the bucket platform, varying soil density, the diameter and embedment depth of the bucket. The numerical modeling was verified and compared with the moment-rotation curve from a field loading test. The uniform sandy ground was assumed and the moment load was applied at the top plate of the platform, increasing bucket rotation. The moment-rotation relations were analyzed to determine the moment capacity, which was influenced by the embedment depth and diameter of the bucket. Finally, a preliminary design equation was suggested to estimate the moment bearing capacity.

Keywords
Bearing capacity
Bucket platform
Cut-off wall
Numerical simulation
Sand

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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 : 35
  • No :12
  • Pages :101-109
  • Received Date : 2019-11-08
  • Revised Date : 2019-11-14
  • Accepted Date : 2019-11-18
  • DOI :https://doi.org/10.7843/kgs.2019.35.12.101
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