All Issue

2017 Vol.27, Issue 2 Preview Page

Research Article

Slope Stability Assessment Induced by Variation in Mountain Topography and Rainfall Infiltration

산지지형 및 강우 침투양상 변화에 따른 산지사면 안정성 평가

Man-Il Kwon1*
,
Seung-woo Lee1
,
Byung-Sik Kim2
김 만일1*
,
이 승우1
,
김 병식2
1National Forestry Cooperative Federation
2Kangwon National University
1산림조합중앙회 산림공학연구소
2강원대학교 방재전문대학원
* 교신저자* Corresponding Author
June 2017. pp. 125-132
PDF XML Citation
Abstract

Approximately 64 percent of Korean territory is covered with mountains, and there is occurred a continuous mountain disaster such as landslide, debris flow and slope failure around mountain slopes due to heavy rainfall and typhoon in the summer season.Even in such a reality, the development of mountain areas is being carried out through the development and expansion of socialinfrastructures centered on mountain areas, but systematic management is insufficient. Constructions of a forest road facility formountain slopes can be a cause of mountain disasters intensively in the summer season due to artificially changing the mountainarea. In this unstable mountain environment, efforts to build a disaster-resistant environment are urgently needed. This research isto analyze the stability of mountain slopes according to soil depth (1~5m) and mountain slope (20~60o) considering the charac-teristics of rainfall infiltration under extreme rainfall conditions. As a result, the stability of the mountain slope was found to bedifferent according to the depth of soils and the saturation area of the soil layer. As well as the stability of the mountain area wasfound to be lower than that of the natural mountain area. Specially, rainfall infiltration occurs at the upper slope of the forest road.For this reason, the runoff phenomenon of rainfall infiltration water occurs clearly when the depth of soil layer is low.

Keywords
mountain slope
forest road
rainfall infiltration
landslide, stability

우리나라는 국토의 64% 가량이 산지로 되어 있어 하절기 집중호우 및 태풍으로 인해 지속적인 산지재해(사면붕괴, 산사태, 토석류 등)가 발생하고 있다. 이러한 산지를 중심으로 사회기반시설의 개발 및 확충을 통해 산지 개발이 이루어지고 있으나 체계적인 관리는 미흡한 실정이다. 산지사면을 대상으로 임도시설의 개설은 대상 산지를 인위적으로 변화시킴에 따라 하절기에 집중적으로 산지재해 발생의 원인으로도 작용한다. 이처럼 불안정한 상태의 산지환경에서 재해에 강한 환경을 건설하기 위한 노력이 절실히 요구되는 시점이다. 본 연구는 자연산지와 산지 내 임도 개설 여부를 기준으로 극한강우 조건하에서 강우의 침투특성을 고려하여 토층심도(1~5m) 및 산지경사(20~60o) 조건에 따른 산지사면의 안정성을 분석하였다. 그 결과, 산지사면의안정성은 토층심도와 토층의 포화면적에 따라 안전율의 차이를 갖는 것으로 나타났으며, 산지 내 임도 개설에 따른 산지의 안정성이 자연산지보다 낮은 것으로 분석되었다. 특히, 강우 침투양상의 경우에는 임도 상부측 사면부에서 강우 침투수의 유출이 발생하는데 이는 토층심도가 낮을수록 유출 현상이 뚜렷이 발생하는 것으로 나타났다.

키워드
산지사면, 임도
침투양상
산사태
안정성
References
1
Chae, B.-G. and Kim, M.-I., 2012, Suggestion of a method for landslide early warning using the change in the volumetricwater content gradient due to rainfall infiltration, Envi-ronmental Earth Sciences, 66, 1973-1986.
10.1007/s12665-011-1423-z
2
Fourie, A. B., Rowe, D. and Blight, G. E., 1999, The effect of infiltration on the stability of the slopes of a dry ash dump, Geotechnique, 49, 1-13.
10.1680/geot.1999.49.1.1
3
Fredlund. D. G.,Xing. A., 1994. Equations for the soil water characteristic curve, Geotech, 31, 512-532 (in Canada).
10.1139/t94-06110.1139/t94-120
4
Geo-Slope, User's Guide for SEEP/W v2007, Geo-slope international Ltd. 369-417.
5
Green, R. E., Corey, J. C., 1971, Calculation of hydraulic conductivity : a further evaluation of predictive methods, Soil Science Society of America, Proceedings, 35, 3-8.
6
Jeong, S. S. and Choi, J. Y., 2009, Stability analysis of unsaturated weathered soil slopes considering rainfall duration, Korean Society of Civil Engineers, 29(1), 1-9 (in Korean with English abstract)
7
Kim, J. H. and Kim, W. Y., 2013, Review of research trends on landslides hazards, Korean Journal of Engineering Geology, 23(3), 305-314 (in Korean with English abstract)
10.9720/kseg.2013.3.305
8
Kim, K. S., Song, Y. S., Chae, B. G., Cho, Y. C. and Lee, C. O., 2007, Geometric characteristics of landslides on natural terrain according to the geological condition, Korean Journal of Engineering Geology, 17(1), 75-87 (in Korean with English abstract)
9
Kim, M.-I., Chae, B.-G. and Han, B.-W., 2008, Evaluation of infiltration characteristics of rainfall in gneiss weathered soil by a filed monitoring, Korean Journal of Engineering Geology, 18(4), 567-575 (in Korean with English abstract)
10
Kim, W. Y. and Chae, B. G., 2009, Characteristics of rainfall, geology and failure geometry of the landslide areas on natural terrains, Korea, Korean Journal of Engineering Geology, 19(3), 331-344 (in Korean with English abstract)
11
Korea Forest Service, 2014, Technical textbook of erosion control, 432p.
12
Lee, G. H., Oh, S. R., Lee, D. U. and Jung, K. S., 2012, Analysis on Mt. Umyeon landslide using infinite slope stability model, Academic publication of Korea water resources association, 737-741.
13
Lee, G. H. and Park, J. P., 2012, Assessment of landslide susceptibility using a coupled infinite slope model and hydro-logic model in Jinbu area, Gangwon-Do, Economic and Environmental Geology, 45(6), 697-707.
10.9719/EEG.2012.45.6.697
14
Ministry of Construction and Transportation, 2011, Road drainage design and maintenance instructions, Appendix. (inKorean)
15
Oh, S. B., Mun, J. H., Kim, T. K. and Kim, Y. K., 2008, A case study of rainfall-induced slope failures on the effect of unsaturated soil characteristics, 28(3), Korean Society of Civil Engineers, 28(3), 167-178 (in Korean with English abstract)
16
Trandafir, A. C., Sidle, R. C., Gomi, T. and Kamai, T., 2008, Monitored and simulated variations in matric suction during rainfall in a residual soil slope, Environmental Earth Sciences, 55, 951-961.
10.1007/s00254-007-1045-7
17
Tsai, T.-L., 2010, Influence of soil water characteristic curve on rainfall-induced shallow landslides, Environmental Earth Sciences, DOI 10.1007/s12665-101-0868-9.
Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 27
  • No :2
  • Pages :125-132
  • Received Date : 2017-04-05
  • Revised Date : 2017-04-18
  • Accepted Date : 2017-04-21
  • DOI :https://doi.org/10.9720/kseg.2017.2.125
Journal Informaiton The Journal of Engineering Geology The Journal of Engineering Geology
Online Submission
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close