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2026 Vol.42, Issue 2 Preview Page
Comparison of Depth-dependent Volumetric Water Content in Surface Layers under Rainfall Infiltration via Numerical Analysis

수치해석 및 현장 관측자료 기반 강우 침투에 따른 표층 깊이별 체적함수비 비

Jae-Hong Kim1
,
Tae-Wan Kim2*
김 재홍1
,
김 태완2*
1Member, Associate Prof. Dept. of Civil and Environmental Engineering, Dongshin Univ.
2Member, Graduate Student, Dept. of Civil and Environmental Engineering, Dongshin Univ.
1정회원, 동신대학교 토목환경공학과 부교수
2정회원, 동신대학교 토목환경공학과 박사과정
*Corresponding Author
30 April 2026. pp. 101-111
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Abstract

This study compared the subsurface volumetric water content (VWC) induced by rainfall infiltration with the infiltration behavior simulated through unsaturated seepage analysis across slopes with varying vegetation cover conditions. Under the same rainfall intensity, temporal variations in volumetric water content at different depths were analyzed using monitoring data and numerical simulation results. The results revealed that the numerical analysis more closely reproduced the trends of VWC observed in deforested areas than in forested areas. Notably, the rapid increase in water content during the early stages of rainfall was similarly captured in both field observations and numerical simulations. By contrast, discrepancies arose in the forested area between simulation results and field measurements due to the combined effects of vegetation cover, including rainfall interception and vegetation-induced changes in soil structure. These results suggest that unsaturated seepage analysis that does not consider vegetation cover has limitations in accurately reproducing variations in slope water content. Therefore, analytical approaches that account for changes in hydraulic properties associated with vegetation cover, as well as the influence of plant roots on the soil environment, are necessary.

Keywords
Deforested
Forested
Numerical analysis
Rainfall
Volumetric water content

본 연구는 산림 피복 조건이 다른 비탈면을 대상으로 강우 침투에 의한 지중 함수비 관측값과 수치해석으로 시뮬레이션한 불포화 침투 거동을 비교하였다. 동일 강우 조건에서 체적함수비(Volumetric Water Content, VWC) 모니터링 자료와 불포화 침투해석 결과를 비교하여, 매설 깊이별 함수비의 시간적 변화를 분석하였다. 그 결과, 수치해석은 수풀지역보다는 벌목지역에서 관측된 체적함수비 변화 경향을 비교적 유사하게 재현하였으며, 특히 강우 초기의 급격한 함수비 증가 특성이 현장 계측과 수치해석 결과가 유사하게 묘사되었다. 반면 수풀에 의한 강우 차단 효과와 수풀-토층 구조 변화 등 식생 피복의 복합적인 영향으로 수치해석 결과와 수풀지역의 실제 침투 거동 간에 차이가 발생하였다. 이러한 해석 결과는 식생 피복 조건을 고려하지 않은 불포화 침투해석이 실제 사면의 함수비 변화를 완전하게 재현하는 데에는 제한이 있음을 시사한다. 식생 피복에 따른 수리특성 변화와 식물 뿌리의 토양 환경 영향 등을 반영할 수 있는 해석 접근 방법이 필요할 것으로 판단된다.

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 42
  • No :2
  • Pages :101-111
  • Received Date : 2026-03-12
  • Revised Date : 2026-04-21
  • Accepted Date : 2026-04-22
  • DOI :https://doi.org/10.7843/kgs.2026.42.2.101
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