한국지반공학회논문집 (Journal of the Korean Geotechnical Society)

  • 제30권3호
  • /
  • Pages.29-46
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  • 2014
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  • 1229-2427(pISSN)
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  • 2288-646X(eISSN)
한국지반공학회 (Korean Geotechnical Society)
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모래지반에서 원형기초의 수직-수평 조합하중 지지력과 경사계수에 대한 수치해석 연구

Numerical Studies on Combined VH Loading and Inclination Factor of Circular Footings on Sand

  • 김동준 (현대건설(주) 연구개발본부) ;
  • 윤준웅 (현대건설(주) 연구개발본부) ;
  • 지성현 (현대건설(주) 연구개발본부) ;
  • 최재형 (현대건설(주) 연구개발본부) ;
  • 이진선 (원광대학교 토목환경공학과) ;
  • 추연욱 (국립공주대학교 건설환경공학부)
  • 투고 : 2013.11.27
  • 심사 : 2014.02.27
  • 발행 : 2014.03.31
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초록

모래지반의 지표면에 위치한 거친 바닥면을 가진 강체 원형기초에 대하여 삼차원 수치해석을 통하여 수직-수평 조합하중 조건에서의 지지력을 구하였다. 조합하중 상관도를 효율적으로 산출할 수 있는 swipe 재하방법과 실제 구조물의 하중 조건과 유사한 probe 재하방법을 모사할 수 있는 수치모델을 구현하였으며 요소망의 조밀도에 의한 오차를 소거할 수 있는 분석 절차를 개발하였다. Mohr-Coulomb 소성모델을 사용하고 관련흐름법칙을 적용하여 지반의 내부 마찰각에 따른 수직-수평 조합하중에 대한 지지력 상관도와 경사계수를 산출하였다. Swipe 재하방법의 결과는 probe 재하방법을 사용한 결과와 유사함을 확인하였으며, 거친 바닥면 조건에서 수직-수평 조합하중 지지력 상관도의 내부 마찰각에 따른 변화는 미미하고, 원형기초에 대해서 연속기초 및 사각형기초와 동일한 경사계수를 적용할 수 있는 것으로 나타났다. 하중의 경사가 큰 경우에는 수치모델링을 통해 산출된 원형기초에 대한 지지력 상관도와 경사계수는 기존의 연구 결과보다 작게 평가되었으며, 수치모델링 결과에 영향을 미치는 요인과 향후 연구 방향에 대하여 고찰하였다.

For circular rigid footings with a rough base on sand, combined vertical - horizontal loading capacity was studied by three-dimensional numerical modelling. A numerical model was implemented to simulate the swipe loading and the probe loading methods and an interpretation procedure was devised in order to eliminate the numerical error from the restricted mesh density. Using the Mohr-Coulomb plasticity model, the effect of friction angle was studied under the associated flow-rule condition. The swipe loading method, which is efficient in that the interaction diagram can be drawn with smaller number of analyses, was confirmed to give similar results with the probe loading method, which follows closely the load-paths applied to real structures. For circular footings with a rough base, the interaction diagram for combined vertical (V) - horizontal (H) loading and the inclination factor were barely affected by the friction angle. It was found that the inclination factors for strip and rectangular footings are applicable to circular footings. For high H/V ratios, the results by numerical modelling of this study were smaller than the results of previous studies. Discussions are made on the factors affecting the numerical results and the areas for further researches.

키워드

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피인용 문헌

  1. Behavior and Critical Failure Modes of Strip Foundations on Slopes under Seismic and Structural Loading vol.19, pp.6, 2014, https://doi.org/10.1061/(asce)gm.1943-5622.0001427