All Issue

2025 Vol.41, Issue 6 Preview Page
Analysis of Failure Susceptibility due to Rainfall Infiltration Considering Vegetation Conditions on Slopes

비탈면 식생 유무에 따른 강우침투에 의한 붕괴 민감도 분석

Jae-Hong Kim1
,
Hyung-Sik Yoo2
,
Yong-Joon Choi3
,
Tae-Wan Kim4*
김 재홍1
,
유 형식2
,
최 용준3
,
김 태완4*
1Member, Associate Prof., Dept. of Civil and Environmental Engineering, Dongshin Univ.
2Member, Managing Director, Yeongjin Engineering Co., Ltd.
3Member, Graduate Student, Dept. of Civil and Environmental Engineering, Dongshin Univ.
4Member, Graduate Student, Dept. of Civil and Environmental Engineering, Dongshin Univ
1정회원, 동신대학교 토목환경공학과 부교수
2정회원, (주) 영진엔지니어링 대표이사
3정회원, 동신대학교 토목환경공학과 박사과
4정회원, 동신대학교 토목환경공학과 박사과정
*Corresponding Author
31 December 2025. pp. 89-97
PDF XML Citation
Abstract

To identify the causes of slope failures associated with logging activities, soil moisture sensors were installed in both forested and deforested areas to monitor rainfall infiltration during the rainy season. This study examined a method for evaluating shallow slope failure using the volumetric water content gradient (VWCG) and the Effective cumulative rainfall (ECR) under different vegetation conditions. A real-time monitoring system based on a Wireless Sensor Network was established to measure soil moisture at multiple locations, from which VWCG values were calculated. The relationship between VWCG, ECR values, and observed slope failures was then analyzed. The results show that slope failures occurred primarily in areas where both indices reached high values simultaneously. Vegetated slopes were generally characterized by VWCG values below 0.1 and ECR values below 60 mm, whereas deforested slopes were concentrated in regions where VWCG exceeded 0.2 and ECR ranged from 40 to 70 mm. Failure probability increased with increasing values of both indices. In particular, slope failures were most frequently observed under conditions of VWCG ≥ 0.3 and ECR ≥ 80 mm, which are proposed as key threshold values for early warning of shallow slope failures.

Keywords
Deforested area
Effective cumulative rainfall
Forested area
Slope failure
Volumetric water content gradient

산비탈에 벌목으로 인한 비탈면 붕괴가 발생하는 원인을 확인하고자 수풀지역과 벌목지역이 혼재된 사면을 대상으로 함수비 센서를 설치하여 장마철 강우량 침투를 분석하였다. 본 연구에서는 식생 유무에 따른 체적함수비 증가 기울기(VWCG; Volumetric Water Content Gradient)와 유효누적강우량(ECR; Effective Cumulative Rainfall)을 활용하여 표층붕괴를 판단하는 방법을 고찰하였다. 분석 절차는 다음과 같다. 먼저, 무선센서네트워크(WSN; Wireless Sensor Network) 기반 실시간 계측시스템을 구축하여 구역별 토양 수분 함량을 측정하고 이를 토대로 체적함수비 증가 기울기(VWCG)를 산정하였다. 이후 산정된 VWCG와 ECR 값을 이용하여 표층붕괴와의 상관성을 검토하였다. 분석 결과, 체적함수비 증가 기울기(VWCG)와 유효누적강우량(ECR)이 동시에 높은 구간에서 실제 붕괴가 발생하였다. 수풀지역은 주로 VWCG 0.1 이하, ECR 60 mm 이하 범위에 분포하였으며, 벌목지역은 VWCG 0.2 이상, ECR 40~70 mm 범위에 집중적으로 나타났다. VWCG와 ECR이 높을수록 붕괴 발생 가능성이 증가하였으며, 이는 식생 분포가 임계값의 변동에 직접적인 영향을 미치는 것으로 확인되었다. 특히, VWCG ≥ 0.3 및 ECR ≥ 80 mm 조건에서 붕괴 발생이 집중적으로 관찰되어 본 연구에서는 이를 표층붕괴 조기경보를 위한 주요 임계값으로 제시하였다.

References
1

Bishop, D. M. and Stevens, M. E. (1964), “Landslides on Logged Areas in Southeast Alaska”, Northern Forest Experiment Station, Forest Service, U.S. Department of Agriculture, pp.18.

2

Chae, B. G. and Kim, M. I. (2012), “Suggestion of a Method for Landslide Early Warning Using the Change in the Volumetric Water Content Gradient due to Rainfall Infiltration”, Environmental Earth Sciences, Vol.66, No.7, pp.1973-1986, https://doi.org/10.1007/s12665-011-1423-z.

10.1007/s12665-011-1423-z
3

Endo, T. (1980), “Effect of Tree Roots Upon the Shearing Strength of Soil”, Japan Agricultural Research Quarterly, Vol.14, No.2, pp.112-115.

4

Glade, T. (2003), “Landslide Occurrence as a Response to Land Use Change: A Review of Evidence from New Zealand”, Catena, Vol.51, No.3-4, pp.297-314, https://doi.org/10.1016/S0341-8162(02)00170-4.

10.1016/S0341-8162(02)00170-4
5

Imaizumi, F. and Sidle, R. C. (2012), “Effect of Forest Harvesting on Hydrogeomorphic Processes in Steep Terrain of Central Japan”, Geomorphology, Vol.169, pp.109-122, https://doi.org/10.1016/j.geomorph.2012.04.017.

10.1016/j.geomorph.2012.04.017
6

Kim, J. H., Jeong, S. S., Park, S. W., and Sharma, J. (2004), “Influence of Rainfall-induced Wetting on the Stability of Slopes in Weathered Soils”, Engineering Geology, Vol.75, pp.251-262, https://doi.org/10.1016/j.enggeo.2004.06.017.

10.1016/j.enggeo.2004.06.017
7

Kim, J. H., Jeong, S. S., Kim, Y. M., and Lee, K. W. (2013), “Proposal of Design Method for Landslides Considering Antecedent Rainfall and In-situ Matric Suction”, Journal of the Korean Geotechnical Society, Vol.29, No.12, pp.11-24, http://dx.doi.org/10.7843/kgs.2013.29.12.11.

10.7843/kgs.2013.29.12.11
8

Kim, M. I., Chae, B. G., Cho, Y. C., and Seo, Y. S. (2008), “Study on Rainfall Infiltration Characteristics for Weather Soils: Analysis of Soil Volumetric Water Content and its Application”, The Journal of Engineering Geology, Vol.18, No.1, pp.83-92, https://scienceon.kisti.re.kr/srch/selectPORSrchArticle.do?cn=JAKO200818259603089.

9

Lee, S. C., Hong, M. H., and Jeong, S. S. (2023), “Landslide Analysis Using the Wetting-Drying Process-Based Soil-Water Characteristic Curve and Field Monitoring Data”, Journal of the Korean Geotechnical Society, Vol.39, No.5, pp.13-26, https://doi.org/10.7843/KGS.2023.39.5.13.

10.7843/KGS.2023.39.5.13
10

Lehmann, P., Ruette, J. V., and Or, D. (2019), “Deforestation Effects on Rainfall-Induced Shallow Landslides: Remote Sensing and Physically-Based Modelling”, Water Resource Research, Vol.55, No.11, pp.9962-9976, https://doi.org/10.1029/2019WR025233.

10.1029/2019WR025233
11

Megahan, W. F., Day, N. F., and Bliss, T. M. (1978), “Landslide Occurrence in the Western and Central Northern Rocky Mountain Physiographic Province in Idaho”, In 5th, North American Forest Soils Conference, pp.116-139.

12

Montgomery, D. R., Schmidt, K. M., Greenberg, H. M., and Dietrich, W. E. (2000), “Forest Clearing and Regional Landsliding”, Geology, Vol.28, No.4, pp.311-314, https://doi.org/10.1130/0091-7613(2000)028<0311:FCARL>2.3.CO;2.

10.1130/0091-7613(2000)028<0311:FCARL>2.3.CO;2
13

Park, S. I., Yoo, H. S., Kim, J. H., and Kim, T. W. (2024), “Analysis of Rainfall Infiltration and Slope Stability in Deforested and Forested Areas Using Real-Time Water Content Monitoring”, Journal of the Korean Geotechnical Society, Vol.40, No.6, pp.45-55, https://doi.org/10.7843/KGS.2024.40.6.45.

10.7843/KGS.2024.40.6.45
14

Saito, H., Murakami, W., Daimaru, H., and Oguchi, T. (2017), “Effect of Forest Clear-cutting on Landslide Occurrences: Analysis of Rainfall Thresholds at Mt. Ichifusa, Japan”, Geomorphology, 276, pp.1-7, https://doi.org/10.1016/j.geomorph.2016.09.024.

10.1016/j.geomorph.2016.09.024
15

Seo, W. G., Choi, J. H., Chae, B.G., and Song, Y. S. (2017), “Characteristics of Landslide Occurrence and Change in the Matric Suction and Volumetric Water Content due to Rainfall Infiltration”, The Journal of Engineering Geology, Vol.27, No.4, pp.475-487, https://doi.org/10.9720/kseg.2017.4.475.

10.9720/kseg.2017.4.475
16

Sidle, R. C., Pearce, A. J., and O'Loughlin, C. L. (1985), “Hillslope Stability and Land Use”, American Geophysical Union, American Geophysical Union, Wasington, U.S.A, pp.140.

17

Sidle, R. C. (1992), “A Theoretical Model of the Effects of Timber Harvesting on Slope Stability”, WATER Resource Research, Vol.28, No.7, pp.1897-1910, https://doi.org/10.1029/92WR00804.

10.1029/92WR00804
18

Suk, J. W., Kang, H. S., Choi, S. G., Jeong, H. S., and Song, H. S. (2020), “Characterization of Increases in Volumetric Water Content in Soil Slopes to Predict the Risk of Shallow Failure”, The Journal of Engineering Geology, Vol.30, No.4, pp.485-496, https://doi.org/10.9720/kseg.2020.4.485.

10.9720/kseg.2020.4.485
19

Suk, J. W., Park, S. W., Na, G. H., and Kang, H. S. (2018), “A Study for Characterization on Shallow behavior of Soil Slope by Flume Experiments”, The Journal of Engineering Geology, Vol.28, No.3, pp.489-499, https://doi.org/10.9720/kseg.2018.3.489.

10.9720/kseg.2018.3.489
20

Suk, J. W., Song, H. S., Kang, H. S., and Kim, H. J. (2019), “A Study on Applicability of Volumetric Water Content to Predict Shallow Failure”, Journal of the Korea Academia-Industrial, Vol.20, No.12, pp.737-746, https://doi.org/10.5762/KAIS.2019.20.12.737.

10.5762/KAIS.2019.20.12.737
21

Wu, T. H., McKinnell III, W. P., and Swanston, D. N. (1979), “Strength of Tree Roots and Landslides on Prince of Wales Island, Alaska”, Canadian Geotechnical Journal, Vol.16, No.1, pp.19-33.

10.1139/t79-003
22

Yoo, H. S. (2025), “A Study on Shallow Failure Warning Criteria according to Soil Cover on Slopes based on Real-Time Monitoring”, Department of Civil Engineering Graduate School, Dongshin University, https://www.riss.kr/link?id=T17290222.

Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 41
  • No :6
  • Pages :89-97
  • Received Date : 2025-10-28
  • Revised Date : 2025-11-27
  • Accepted Date : 2025-11-28
  • DOI :https://doi.org/10.7843/kgs.2025.41.6.89
Journal Informaiton Journal of the Korean Geotechnical Society Journal of the Korean Geotechnical Society
Archives
: Vol.23~28 (2007~2012)
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close