A Study on Comparison of Finite Element Analysis with Model Test of Shallow Footing Failure for Cohesionless Soil with Non-associated Plasticity and Some Smooth Footing

사질토지반의 지지력분석을 위한 얕은기초의 파괴거동에 대한 모형실험과 유한요소해석 비교 검토

  • 김영민 (전주대학교 토목환경공학과) ;
  • 강성귀 (전주대학교 토목환경공학과)
  • Received : 2009.12.12
  • Accepted : 2009.12.21
  • Published : 2010.03.30

Abstract

This paper describes the procedure to predict the entire load-displacement curve and the failure mechanism of shallow strip footing for real soil. The presented results show that it is possible to analyze the post peak behavior of shallow strip footing and to give a progressive failure mechanism clearly. Finite element computation of the bearing capacity factor $N_{\gamma}$ have been made for shallow strip footings with friction angles and dilation angle. It is shown that commonly used values of $N_{\gamma}$ which have generally been based on associated plasticity calculations are unconservative for real soil with non-associated plasticity and some smooth footing.

본 연구에서는 얕은기초의 파괴거동과 전체적인 하중-변위 관계를 묘사하는 방법에 대하여 기술하였다. 제안한 방법에 의하여 얕은기초의 최고점 이후의 거동과 점진적인 파괴과정을 비교적 명확히 기술하는 것이 가능함을 보여주었다. 유한요소 수치해석법으로 얕은 기초지반에 대하여 마찰각과 체적팽창각을 달리하여 지지력계수 $N_{\gamma}$을 계산하였다. 일반적으로 적용하는 관련 흐름법칙과 거친 기초조건에 의한 지지력계수 $N_{\gamma}$값은 실제 흙거동인 비관련 흐름법칙과 약간 미끈한 기초조건에 대해서는 불안전한 설계가 되는 것을 보여주었다.

Keywords

References

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