Triggering factor analysis of deposit slope under rainfall infiltration based on laboratory experiments

Abstract

The identification and analysis of the deposit slope stability is the focus of geological disaster prevention and control. Taking dense-fine grained slopes and loose gravel slopes as examples, a series of flume tests under rainfall infiltration were carried out. The effects of density, material composition, slope angle and vegetation coverage on slope stability and rainfall threshold were systematically analyzed. The results show that under rainfall infiltration, the dense-fine grained slope with uniform material composition and high density was more stable, resulting in a higher rainfall threshold and a lower catastrophability. The slope with non-uniformmaterial composition and loose gravel was more likely to fail than the slope with dense fine particles. The influence of the stone content on the stability of the slope is greater than that of the slope gradient. The critical rainfall of landslides increases first and then decreases with an increasing vegetation coverage; that is, when rainfall infiltration causes the slope soil to be supersaturated, the higher vegetation coverage will trigger the whole deformation of slope and vegetation due to the strong development of vegetation roots, which increases the catastrophability of the slope.The research results can provide a theoretical basis for the instability mechanism and stability evaluation of deposit slopes.

Keywords

• dense fine particle slope
• loose gravel slope
• volume water content
• pore water pressure
• vegetation coverage
• rainfall infiltration