Slope Stability Analysis of Unsaturated Soil Slopes Based on the Site-Specific Characteristics: A Case Study of Hwangryeong Mountain, Busan, Korea

Abstract

Shallow slope failures occur almost every year during the rainy season. Continuous observation of the meteorological parameters and hydrological characteristics is required to more clearly understand the triggering mechanisms of shallow slope failure. In addition, influential factors, such as type of relative permeability models, air flow, and variation of hydraulic conductivity associated with stress–strain behavior of soil, have significant effects on the actual mechanism of rainfall infiltration. Real-time data including hourly rainfall and pore water pressure in response to rainfall was recorded by devices; then, the change in pore pressure from the devices was compared to the results from the infiltration analysis with applications of three relative permeability models, air flow, and the coupled hydro-mechanical analysis to examine an appropriate site-specific approach to a rainfall infiltration analysis. The infiltration and stability analyses based on the site-specific hydrologic characteristics were utilized to create maps of safety factors that depend on the cumulative rainfall. In regions vulnerable to landslides, rainfall forecast information and safety factor maps built by applying various rainfall scenarios can be useful in preparing countermeasures against disasters during the rainy season.

Stability Analysis of a High-Steep Dump Slope under Different Rainfall Conditions

“…Pore water pressure is one of the important indexes used to evaluate the slope stability [4]. Pore water pressure increases with time in soils with high water content.…”

“…The waste dump formed by loose residue is one of the regions in the mining area with fragile geotechnical and ecological characteristics. This type of accumulation satisfies the stress balance at the initial stage and gradually forms a high-steep slope after being dumped, which is prone to accumulate and swell at the foot of the slope, causing a failure trend along the slope, resulting in safety hazards [4,5]. These geotechnical issues pose a substantial risk to both people and property.…”

The Characteristics and Seepage Stability Analysis of Toppling-Sliding Failure under Rainfall

“…Rainfall is an important factor in triggering landslides [19][20][21][22][23]. It often leads to a rise in groundwater level or the development of the perched water zone, both of which may result in the reduction in soil matric suction (an increase in pore-water pressure).…”

The Use of Soil Moisture and Pore-Water Pressure Sensors for the Interpretation of Landslide Behavior in Small-Scale Physical Models

“…Various approaches have been successfully applied to investigate the hydraulic and mechanical response of slopes exposed to different rainfall conditions and the mechanisms leading to the initiation of rainfall-induced landslides. For example, numerical modelling has been successfully used to investigate how different factors affect the stability of both shallow (e.g., [ 1 , 7 , 8 , 10 , 16 , 17 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ]) and deep-seated landslides under different rainfall conditions (e.g., [ 19 , 43 , 44 , 45 , 46 , 47 , 48 ]). Field monitoring has been successfully used to observe the hydraulic and mechanical performance of slopes in different geological and climatic contexts (e.g., [ 7 , 17 , 21 , 22 , 31 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ...…”