Indoor model test of red clay slope under evaporation-rainfall

Abstract

Evaporation-rainfall is one of the main causes of red clay slope failure. In order to explore the evolution law and mechanism of red clay slope failure under evaporation-rainfall, this paper takes Guizhou red clay as the research object, establishes slope model in laboratory, and analyzes the failure characteristics, failure mode and failure mechanism of red clay slope under evaporation-rainfall. The test results show that the failure mode of red clay slope under evaporation-rainfall is: splash erosion and surface erosion stage → crack development stage → gully formation stage → gully development stage → local collapse stage → slope foot collapse stage. During the test, there is no obvious sliding surface on the slope. In the process of rainfall, the free water inside the slope converges to the foot of the slope under the action of gravity, which results in the maximum moisture content at the foot of the slope, and the strength of the soil decreases sharply. The local collapse occurs at the foot of the slope first. When several collapses are connected and the structure of the slope foot cannot support the weight of the upper shallow soil, the collapse occurs to the middle and upper part of the slope exhibition.