Numerical Analysis and Comparison of the Influence of Safety Factor Variations in Slope Stability During Rainy Season

Pyung-Hyun Song; Yong Baek; Byung-Ok You; Young-Cheol Hwang

doi:10.7843/kgs.2014.30.10.45

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2014 Vol.30, Issue 10 Preview Page Next Page

Numerical Analysis and Comparison of the Influence of Safety Factor Variations in Slope Stability During Rainy Season 우기시 비탈면 안전율 변화 인자의 영향에 대한 수치해석적 비교연구

31 October 2014. pp. 45-54

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Abstract

Many studies have been made on investigation, design, explanation and treatments etc. to minimize slope failure. However, the problem is that failures of cutting slope and natural slope due to Typhoon and localized heavy rainfall are still not reduced. It is difficult to treat the problem by only strengthening the design standard. And it is very necessary to carry out design and safety analysis under the most suitable conditions considering foundation and rainfall characteristics. In this study, variations of safety factor were discussed from different aspects to investigate the influence of different parameters of rainfall and analysis conditions. Rainfall and foundation conditions are supposed to be the most sensitive parameters to slope stability, and numerical analysis were performed by changing parameters of the two conditions. Rainfall behavior is based on the domestic statistical rainfall and foundation condition is selected as unsaturated soils. Study results show that, application of rainfall characteristics in different area and parameters of unsaturated soils are responding sensitively to variations of slope safety. Therefore, the input parameters should be fully examined when performing the practical design.

Keywords

Seepage analysis

Rainfall intensity

Rainfall duration,

unsaturated soil

Parameter of stability

비탈면 붕괴를 최소화 하기 위하여 조사, 설계, 해석, 대책방안 등의 연구가 많이 수행되고 있다. 그러나, 최근 태풍 및 집중호우로 인하여 비탈면 및 자연 사면의 산사태 발생빈도는 줄지 않고 있다. 단순한 설계 기준의 강화만으로는 적절한 대책을 마련하기 어려운 실정이다. 따라서, 지반과 강우를 고려한 최적의 조건에서 설계 및 안정해석을 실시하여야 한다. 본 연구는 비탈면 해석시 강우 및 해석조건에 대하여 각 변수의 영향을 살펴보고자 안전율의 변화를 다각도로 검토한 것이다. 연구방법으로는 비탈면 안정에 가장 민감하게 반응한다고 판단되는 강우조건과 지반조건을 선정하였고, 각각의 조건변수를 변화시켜가면서 수치해석적 검토를 수행하였다. 강우특성으로는 국내의 확률강우특성을 기반으로 해석을 수행하였으며 지반조건으로는 불포화토를 대상으로 검토를 실시하였다. 연구결과, 지역별 강우특성과 불포화토의 매개변수 적용이 비탈면 안전율 변화에 민감하게 반응하는 것으로 나타났다. 따라서, 설계시 입력변수에 대한 충분한 검토가 선행되어야 할 것이다.

References

1.Ministry of Land Infrastructure and Transport (2011), Construction of slope design criteria.

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11.Geo-Slope International Ltd “SLOPE/W User’s Guide”.

Information

Publisher :The Korean Geotechnical Society
Publisher(Ko) :한국지반공학회
Journal Title :Journal of the Korean Geotechnical Society
Journal Title(Ko) :한국지반공학회 논문집
Volume : 30
No :10
Pages :45-54
Received Date : 2014-07-23
Revised Date : 2014-08-11
Accepted Date : 2014-10-23
DOI :https://doi.org/10.7843/kgs.2014.30.10.45

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

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