Development of Eco-Friendly Soil Improvement Agent for Enhanced Slope Stability and Erosion Control in Urban Areas

Abstract

Due to the impact of climate change, extreme rainfall events are becoming more frequent, resulting in shallow slope collapse and erosion that trigger debris flows. While traditional reinforcement methods like anchoring and nailing are effective, they can be costly and environmentally unfriendly. To address this issue, researchers have investigated using in situ soil reinforcement with vegetation, which is a more sustainable and economical option. In this study, a soil improvement agent was developed using leaf mold and herbal medicine to promote vegetation growth. Adding microcement and gypsum hemihydrate increased the shear strength of the soil, preventing surface erosion. A laboratory test confirmed that the combination of these ingredients effectively increased the soil’s resistance to erosion caused by rainfall. The soil improvement agent proposed in this study was applied to the case of the slope failure in the Gwangju area, South Korea, to confirm the slope stability for 10 days of rainfall. The results of numerical analysis confirmed that the reinforced slope cured by the pozzolanic reaction using the developed material improved the slope stability by 36% compared to the original soil slope during the rainy season.