Experimental and numerical investigation on failure mechanism of expansive soil subgrade slope

Abstract

Shallow landslides of expensive soil slopes occur from time to time, and most engineering geological problems are directly or indirectly caused by soil structure cracks. The existence of tensile cracks can significantly affect the hydro-mechanical properties of soils. In this paper, the mechanism of expansive soil landslide formation is explored, and swelling pressures, and drying and wetting cycles are introduced into the discrete element method (DEM), and the landslide process of expansive soils is studied by the numerical simulation mothed. The relationship between the crack development and the instability of expansive soil slopes was investigated. The results show that under the condition of seasonal dry and wet alternation, the cracks of the expansive soil slope gradually develop, the rainwater infiltrates rapidly, the mechanical properties gradually deteriorate, and under the effect of such adverse cycle, the soil gradually softens and the stability decreases. Under the influence of human activities, vehicle loads and other factors, the slope body slides. These findings are helpful for the design and construction of expansive soil slopes and foundations.