压实黄土路堤是主要的路基型式之一，由降雨引起的压实黄土含水率增大导致的高填方路堤边坡失稳时有发生。通过对山－平（山阴至平鲁）高速公路黄土路堤填料进行室内击实试验和三轴压缩试验，分析了填土含水率对填土密度、干密度及填土抗剪强度的影响。结果表明，含水率对黄土填料密度和干密度的影响都较大；随着含水率的变化，填土黏聚力和内摩擦角呈现一增一减的变化规律。根据试验结果，采用FLAC3D建立现场试验段加筋路堤数值模型，基于强度折减法分析4种加筋工况下含水率对黄土填土路堤稳定性的影响表明，随着填土含水率的增大，路堤安全系数不断减小，路堤稳定性降低；路堤安全系数随土工格栅铺设层数的增加而增大，在路堤中铺设土工格栅能够提高路堤整体性，很好地防止路堤失稳。

As one of the main types of subgrade, the slope instability of high-fill compacted loess embankment occurs frequently due to the increase of water content caused by rainfall. The effect of water content on density, dry density and shear strength of loess sampling from the embankment-fill of Shanyin-Pinglu expressway, is investigated by a series of laboratory soil tests mainly including compaction test and triaxial compression test. The results show that the water content has great influence on the density and dry density of loess fill. In addition, with the variation of water content, the cohesion increases while the internal friction angle decreases. According to the tests results, the numerical model is established using FLAC3D and the stability of reinforced and unreinforced embankment with different water contents based on strength reduction method is studied. The results show that the safety factor of embankment decreases with the increase of water content of compacted loess which can lead to the stability of embankment decreases. Moreover, the safety factor of embankment increases as the geogrid layers increase. The integrity of embankment is well enhanced with the inclusion of geogrid, thus the possibility of slope instability is reduced.