库水位升降条件下不同渗透性的滑坡体稳定性变化规律

Stability variation of landslide with different permeability coefficient following reservoir water level fluctuation

库水位升降作用下不同材料滑坡体稳定性变化规律不同。选择代表三峡库区不同土体材料滑坡4个数量级的饱和渗透系数,采用Geostudio软件Seep/W和Slope/W模块,分析了三峡水库库水位升降作用下不同渗透系数滑坡体浸润线的分布规律及由此引起的滑坡稳定性变化规律,结果表明:库区涉水滑坡体稳定性的变化与滑坡体的渗透系数密切相关,在库水位上升阶段,随着滑坡体渗透系数逐渐变小,浮托力增大的速率变缓,指向坡内的渗压逐渐增强,滑坡稳定性系数有相对增大趋势。在库水位下降阶段,随着滑坡体渗透系数逐渐变小,浮托力减小的速率变缓,指向坡外的渗压逐渐增强,滑坡稳定性系数有相对减小趋势。

Stability variation for different landslide is different under the reservoir water level. According to the four orders of magnitude permeability coefficients which represent the different landslide material in Three Gorges Reservoir, using. Seep / W program and slope/W program of geostudio software, distribution rule of landslide saturation line for different permeability coefficients and stability variation rule of landslide were analyzed under reservoir water level fluctuation. The results show that： the landslide stability variation in the reservoir area is closely related to landslide permeability coefficients. In the rising phase of reservoir water level, with the gradual decrease of landslide permeability coefficient, the rate of uplift force increase is slowing down; the seepage pressure, which is pointing to the inner landslide, increases gradually, and the landslide stability coefficient increases relatively. In the descending phase of reservoir water level, with the gradual decrease of landslide permeability coefficient, the rate of uplift force decrease is slowing down; the seepage pressure, which is pointing to the outside landslide, increases gradually, and the landslide stability coefficient decreases relatively.