Rainfall Infiltration Test and Numerical Simulation Analysis of a Large Unsaturated Soil Slope
Publication: Journal of Hydrologic Engineering
Volume 29, Issue 4
Abstract
Rainfall infiltration is the primary factor affecting slope stability, which may lead to geological hazards such as landslides, collapses, and debris flows. Thus, it is crucial to investigate the rainfall infiltration patterns of unsaturated soil slopes. During a natural rainstorm, the soil volumetric water content at various depths of a significant unsaturated soil slope model was monitored onsite. The soil-water characteristic curve parameters and saturated permeability coefficient of remolded soil were quantified, and the Van Genuchten (VG) model was utilized to forecast the unsaturated permeability coefficient. The numerical simulation method was used to simulate the field rainfall experiment. Based on the mutual verification of the field measurement and numerical simulation, rainfall simulation with different rainfall intensities was added, and its influence on rainfall infiltration depth, pore water pressure, and transient saturated zone was analyzed. The findings revealed that under the rainstorm intensity of the field rainfall test, the rainfall infiltration depth ranged from 0.2 to 0.4 m after a continuous 9-h rainfall period. As the rainfall intensity increased, the range of soil pore water pressure variations expanded, with a maximum value ranging from 9 to 140 kPa under the rainstorm rainfall intensity. By extending the duration of rainstorm rainfall intensity to 14 h, the depth of the transient saturated zone reached 0.2 m. With a duration of 20 h, it reached 0.4 m. The depth reached 0.6 m after 27 h and 1.5 m after 36 h. The research findings of this paper can provide scientific guidance for revealing the hydrological characteristics of slopes during rainfall and for the protection and reinforcement of slopes.
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Data Availability Statement
All data supporting the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
This work was supported by the National Natural Science Foundation of China (No. 51978249), the Joint Funds of the National Natural Science Foundation of China (No. U22A20232), and the Innovation Group Project of Hubei Science and Technology Department (No. 2020CFA046).
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Information & Authors
Information
Published In
Journal of Hydrologic Engineering
Volume 29 • Issue 4 • August 2024
Copyright
© 2024 American Society of Civil Engineers.
History
Received: Oct 20, 2023
Accepted: Feb 20, 2024
Published online: May 17, 2024
Published in print: Aug 1, 2024
Discussion open until: Oct 17, 2024
ASCE Technical Topics:
- Climates
- Continuum mechanics
- Dynamics (solid mechanics)
- Engineering fundamentals
- Engineering mechanics
- Environmental engineering
- Geomechanics
- Geotechnical engineering
- Hydrologic engineering
- Hydrology
- Infiltration
- Meteorology
- Models (by type)
- Numerical models
- Precipitation
- Pressure (type)
- Rain water
- Rainfall
- Rainfall intensity
- Soil mechanics
- Soil properties
- Soil water
- Soils (by type)
- Solid mechanics
- Unsaturated soils
- Water (by type)
- Water and water resources
- Water management
- Water pressure
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