西南山区高速公路填方工程中常见斜坡软弱路基失稳变形。由于斜坡软弱路基的特殊地层结构,在其上部填筑较厚的路基填料时常常引起路堤坡体下部软弱土层剪应变过大而导致路堤变形和破坏。本文采用地质分析、刚体极限平衡计算、有限差分数值分析等方法,对填方荷载作用下斜坡软弱路基变形特性进行了分析,并根据分析结果提出了加固措施。本文的研究成果对类似工程可提供参考。 Common Instability of Soft Slope on Slope in Southwest Mountainous Expressway Filling Project. Due to the special stratigraphic structure of the weak slope roadbed, filling of the thick embankment in the upper part often causes the shear strain of the soft soil layer in the lower part of the embankment slope to be too large, resulting in the deformation and destruction of the embankment. In this paper, the deformation characteristics of soft subgrade under slope loading are analyzed by means of geological analysis, rigid body limit equilibrium calculation and finite difference numerical analysis. According to the analysis results, the reinforcement measures are proposed. The research results of this paper can provide reference for similar projects.