降雨入渗下根带土水力特性及边坡稳定性研究OA

In order to study the hydraulic characteristics of root zone soil and the influence of vegetation on slope stability under rainfall infiltration,this paper constructs a restoration model of shrub-grass synergistic vegetation community,conducts straight shear tests on root zone soils to quantify the effect of vegetation root reinforcement,and employs rainfall scouring tests to analyze the effect of vegetation slope protection.Furthermore,it uses fish language to perform the secondary development of FLAC3D software,enabling the study of the unsaturated slope stability under the coupling effects of rainfall and root system.The results show that:(1)The root system of vegetation under shrub and grass synergy can significantly enhance the shear strength of the soil,increasing soil cohesion by 85.20%.Additionally,vegetation can effectively inhibit slope erosion under rainfall washout;(2)Under rainfall conditions,the vegetation slope can slow down rainwater infiltration,delay the time required for soil saturation,and,combined with the mechanical reinforcement effect of roots,inhibit the upward shift of potential sliding surfaces.This results in a 37%reduction in the rate of safety factor decay compared to bare slopes;(3)The slope-protection effectiveness of vegetation varies significantly under different rainfall infiltration modes,rainfall intensities,and slope gradients.Under heavy rainfall and steep slope conditions,the slope safety factor decreases substantially;(4)The study reveals synergistic slope-protection mechanism combining the mechanical and hydraulic effects of vegetation.It is recommended that under the shrub-grass synergy model,the slope gradient of spoil-field slopes should be controlled within 45 degrees.This provides scientific guidance for the prevention and control of geological hazards in mountainous areas.