KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Effect of Rainfall-Patterns on Slope Stability in Unsaturated Weathered Soils

강우사상의 영향을 고려한 불포화 풍화사면의 안정성

  • 김병수 (일본 고베대학교 토목공학과) ;
  • 박성완 (단국대학교 토목환경공학과)
  • Received : 2012.10.07
  • Accepted : 2013.04.01
  • Published : 2013.05.30
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Abstract

In this study, two rainfall patterns are utilized for practical consideration of rainfall phenomena in unsaturated soil slope design. One is the I.D.F (Intensity-Duration-Frequency) method which is an existing design rainfall method and ignores the effect of the variation of the rainfall according to the time. The other is the Huff method which considers this effect oppositely. First, the safety of factor of the slope according to the variation of an initial suction which means the precedent rainfall effect was examined by means of the application of the I.D.F method. Through the application of two rainfall patterns, it was discussed how the rainfall pattern affects the factor of safety of the slope. As a result, it is found that the Huff method is more practical on the evaluation of the slope stability than the I.D.F method.

사면안정 해석 시, 사면파괴의 주원인인 강우사상의 현실적 접목을 위하여 본 연구에서는 다음 두 가지 방법을 채택하였다. 하나는 시간에 따른 강우량 변화의 영향을 무시한 기존의 설계강우 방식인 I.D.F(Intensity-Duration-Frequency)곡선을 이용하는 방법이며, 다른 하나는 시간의 영향을 고려하여 강우사상을 표현한 Huff 방법이다. 먼저 I.D.F 방법의 강우사상을 적용하여 선행강우효과를 나타내는 초기흡수력의 변화에 따른 사면의 안전율의 변화를 알아보았다. 또한, 두 강우사상의 방식을 적용하여 강우사상이 사면의 안전율 변화에 미치는 영향을 규명하고자 하였다. 그 결과, Huff 방법의 강우사상이 I.D.F 방법보다 더 현실적으로 사면의 안전성 평가가 이루어 질 수 있음을 확인할 수 있었다.

Keywords

References

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