植物根系吸水对非饱和土边坡稳定性影响的分析

为了量化植物根系吸水对非饱和土边坡稳定性的影响及为植被护坡的植物种类选择提供参考,采用COMSOL Multiphysics建立二维边坡,模拟不同根系形态、根长及降雨条件下的根系吸水引起的非饱和土边坡孔隙水压力的分布变化,并采用极限平衡理论对边坡稳定系数进行定量计算.结果表明:指数形根系吸水产生的吸力最大,比裸坡增大4...

Analysis of the Influence of Root Water Absorption on the Stability of Unsaturated Soils Slope

To quantify the influence of root water absorption on unsaturated soils slope stability and provide reference for plant species selection of vegetation slope protection, a two-dimensional slope was established by COMSOL Multiphysics. The distribution of pore-water pressure in unsaturated soils slope caused by root water absorption under different root morphology, root length and rainfall conditions was simulated, and the slope stability factor was quantitatively calculated using the limit equilibrium method. Results demonstrated that the suction generated by the exponential root uptake water is the largest, which is 4.2 times larger than that of the bare slope, and the suction generated by the parabolic root uptake water is the smallest, which is still 2.7 times larger than that of the bare slope. The longer the root was, the greater the influential depth of water uptake was. The shorter the root was, the greater the suction generated, and the more remarkable the change of suction on the slope surface. After short-term rainfall, the suction of root soil slope was still 12~20 kPa higher than that of bare slope. The exponential root system contributed more to the stability improvement of unsaturated soils slope, which was 1.54 times higher than that of bare slope. While the parabolic root system was the smallest, but it was still 1.36 times higher than that of bare slope. The root water absorption has a positive effect on the stability of the unsaturated soils slope. For vegetation slope protection, priority will be give to the vegetation with the exponential root.