Study on the Influence of Initial State on Loess Erosion Characteristics and Microscopic Mechanism

Abstract

Because of its loose, porous, and vertical structure, loess easily absorbs water, and it contains a large amount of soluble material, making it susceptible to erosion by water flow from rainfall or irrigation, with potentially disastrous consequences. Damage can result especially from loess slope erosion. In this paper, physical tests and microscopic analysis are used to study loess erosion. The purpose is to explore the internal structure of the soil caused by the infiltration of the water body when it flows through the loess slope, and thus to learn more about the internal mechanisms of surface erosion caused by the migration and relocation of the soil particles on the surface of the slope. Erosion tests of samples with different dry density and water content were carried out. It was found that the amount of erosion decreases with an increase of dry density and increases with an increase of water content. Through physical simulation tests combined with field investigation and analysis, the entire erosion process is divided into four erosion characteristic stages: uniform surface erosion; micro drop pit erosion; micro drop pit bead erosion; and rill erosion. The erosion mechanism and micro mechanism of different erosion characteristics are analyzed and summarized. The influences of different dry density and water content on the erosion process are analyzed and summarized, and the internal mechanism of erosion is revealed from the perspective of microstructure, thereby providing a sound basis for engineering construction and erosion-related disaster management in the Loess Plateau.