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Evaluation of Pullout Capacity of Embedded Suction Anchors in Uniform Clay using Numerical Analysis with ALE(Arbitrary Lagrangian Eulerian) Technique

ALE 기법이 적용된 수치해석을 통한 점토지반에서 석션 매입 앵커의 인발 저항력 평가

  • Na, SeonHong (Coastal Development & Ocean Energy Research Division, Korea Institute of Ocean Science and Technology) ;
  • Jang, In-Sung (Coastal Development & Ocean Energy Research Division, Korea Institute of Ocean Science and Technology) ;
  • Kwon, OSoon (Coastal Development & Ocean Energy Research Division, Korea Institute of Ocean Science and Technology) ;
  • Lee, Seung-Hyung (Department of Civil Engineering, Sunmoon University)
  • 나선홍 (한국해양과학기술원 연안개발에너지연구부) ;
  • 장인성 (한국해양과학기술원 연안개발에너지연구부) ;
  • 권오순 (한국해양과학기술원 연안개발에너지연구부) ;
  • 이승현 (선문대학교 토목공학과)
  • Received : 2013.10.22
  • Accepted : 2014.04.10
  • Published : 2014.04.30

Abstract

Numerical analysis with ALE (Arbitrary Lagrangian Eulerian) Adaptive Meshing technique was performed to evaluate the pullout capacity of the embedded suction anchors (ESA) in uniform clay. The numerical method was verified by the previous study, analytical results based on limit-equilibrium theory and centrifuge tests. The pullout capacity of the ESA under horizontal, vertical, and inclined loading were evaluated, and the effect of initial rotation of the ESA on pullout capacity was also investigated. The analysis results showed that the maximum horizontal capacity was obtained at the mid-point, and the each vertical capacity gave the similar value regardless of the loading points. Furthermore, the inclined capacity was decreased as the load inclination angle increased at the mid-point of the anchor, and almost the same pullout capacity was obtained when the initial rotation angles were below 30 degrees.

해상에 활용되는 계류앵커형식 중 한 종류인 석션 매입 앵커(Embedded Suction Anchor; ESA)의 점토지반에서 인발 저항력을 평가하기 위해 ALE(Arbitrary Lagrangian Eulerian) Adaptive Meshing기법을 적용한 수치해석을 수행하였다. 기존에 수행된 원심모형 실험과 한계 평형법을 이용한 해석적 방법의 결과와 비교 분석을 통해 수치해석 기법을 검증하고, 이를 이용해 앵커의 수평, 연직, 그리고 경사 방향의 인발 저항력을 평가하였다. 더불어 경사 방향의 재하 이전에 앵커를 경사각만큼 회전시켜 앵커에 수직한 방향으로 인발이 가해지도록 하여 그 거동을 평가하였다. 그 결과, 수평 재하 시 중간 위치에서 가장 큰 저항이 발휘되었고, 연직 재하의 경우 재하 위치에 따른 저항력의 차이가 크게 나타나지 않았다. 앵커의 중간 위치에서 경사 재하 결과 경사각이 증가할수록 인발 저항력이 감소하였으며, 초기회전이 있는 앵커의 경우 초기회전각이 30도 이하일 때 인발저항력이 일정한 결과를 보였다.

Keywords

References

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