湿度变化对黄土路堤边坡稳定性影响分析

Influence of Humidity on Slope Stability of Loess Embankment

通过三轴压缩试验,分析不同含水率状态下压实黄土填料的强度变化特征,并计算评价了不同湿度、路堤高度、加筋条件下黄土边坡稳定性。结果表明:压实黄土填料强度随着含水率增加而下降,其中黏聚力与含水率呈负指数递减关系,内摩擦角与含水率呈线性递减关系,含水率对压实黄土的黏聚力影响更明显;随着路堤填料湿度上升,边坡稳定系数显著降低,当含水率从施工状态wopt上升5%时,路堤高度10-40m的边坡稳定性系数下降24.3%~37.9%;加筋层中使用的土工格栅抗拉强度越高,土工格栅层间距越小,路堤边坡稳定补强效果越明显。

The strength variation features of compacted loess filling in different cases of moisture content were analyzed through tri axial compression test;and the stability of loess slope in different cases of humidity, embankment height and reinforcement conditions were calculated and evaluated. The result shows that the strength of compacted loess filling decreases with the increment of moisture content, where in the cohesion relates to the moisture content with negative exponential decrease, the internal frictional angle relates to the moisture content with linear decrease, and the moisture content has more obvious impact;as the humidity of embankment filling increases, the coefficient of slope stability decreases greatly, i. e. when the moisture content increases by 5 % from wopt in construction status, the stability coefficient of the embankment in 10 .40 m high decreases by 24. 3 %.37. 9 %;the higher the tensile strength of the geogrid used in the reinforcement layer and the smaller the geogrid interval, the more obvious the reinforcement effect for the embankment slope stability.