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Effect of Rainfall on the Behavior of MSE Wall

강우시 뒷채움재의 투수특성에 따른 보강토옹벽의 거동

  • 김대현 (조선대학교 공과대학 토목공학과) ;
  • 이익효 (전남대학교 공학대학 해양토목공학과) ;
  • 김선학 (조선대학교 공과대학 토목공학과) ;
  • 서준형 (조선대학교 공과대학 토목공학과) ;
  • 이광기 (조선대학교 공과대학 토목공학과)
  • Received : 2011.11.30
  • Accepted : 2012.04.27
  • Published : 2012.06.30

Abstract

Since the collapse of MSE walls frequently occurs due to the rainfall, it is necessary to analyze the behavior of MSE wall depending on the characteristics of rainfall and the properties of permeability of backfill. In order to understand the behavior of MSE wall depending on the characteristics of rainfall and the properties of permeability of backfill, finite element analyses were performed on the typical MSE wall. With varying ratio of saturated permeability to rainfall intensity, porepressures, displacements and factor of safety were analyzed. As the ratio of the saturated permeability to rainfall intensity increases, the global factor of safety is found to increase. Based on the analyses, the use of permeability of backfill with $2.56{\times}10^{-5}m/sec$ is desirable considering the characteristics of rainfall in Korea.

강우시 보강토옹벽의 붕괴가 빈번하게 발생하고 있어 강우특성 및 뒷채움재 투수 특성에 따른 보강토 옹벽의 거동분석은 필수적이다. 이에 본 연구에서는 강우특성과 뒷채움 재 투수특성에 따른 보강토옹벽의 거동을 분석하고자 국내의 보강토옹벽 설계기준에 맞게 모델링 후 강우특성을 반영하여 침투해석 및 유한요소해석을 연계하여 실시하였다. 해석 결과, 강우재현기간 24시간, 48시간, 96시간 조건에서 강우발생기간 및 포화투수계수와 강우강도 비(ks/I)에 따라 보강토옹벽의 배면간극수압, 전면벽체의 최대발생변위, 옹벽전체 안전율의 변화하는 특성을 알 수 있었다. 또한, 포화투수계수와 강우강도 비(ks/I)의 조건에서 투수계수가 증가함에 따라 옹벽 전체안전율이 증가하는 것으로 나타났으며 국내강우특성을 고려할 때 보강토옹벽의 안정을 위해서는 뒷채움재의 투수계수가 최소 $2.56{\times}10^{-5}m/sec$ 보다 큰 것을 사용하는 것이 바람직할 것으로 나타났다.

Keywords

References

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