MODEL EXPERIMENT STUDY ON EROSION OF LOESS SLOPE DUE TO RAINFALL

Slope surface erosion due to rainfall is liable to cause soil erosion and landslide hazard, which is a difficult problem.This paper takes a loess slope as an example and puts forward a comprehensive protection method of ecological slope based on the concept of water reducing and drainage.In order to study on soil erosion law and evolution mechanism of slope under different factors, the simulation experiments were carried out with the self-developed slope rainfall simulator.It considers modifier content, lattice protective form, intensity, duration, aspect ratio on the effect of protection.Test results show that the loess slope surface erosion can be summarized as splash erosion, sheet erosion, gully erosion and landslides.With the increase of the modifier content, the corrosion resistance of the improved slope is enhanced, and the optimal dosage of the modifier is 3‰.Compared with the plain loess slope, rainfall intensity has little influence on improved slope with 3‰modifier.With the increase of rainfall duration, the improvement effect of the modifier is more obvious.Modifier and frame as well as their comprehensive utilization can effectively improve the slope resistance to rainfall erosion.When the slope gradient increases to a certain extent, the slope is prone to collapse suddenly due to the rainfall erosion, which needs to be emphasized.The modifier mainly makes the soil particles more compacted by flocculation, so as to improve the water holding capacity and corrosion resistance of loess.