顺层岩质边坡变形演化成因分析及治理研究

Study on Deformation Mechanism and Control Method of Bedding Rock Slope

桂梧高速公路某段边坡,开挖至第三级边坡时,发生山体滑移。野外工程地质调查发现岩体中存在一组相互正交的共轭节理及多层顺坡糜棱状软弱夹层。通过对其结构面与坡面组合特征的细致研究,阐述了其变形破坏机制。研究结果表明,边坡为倾覆-滑移拉裂的渐进破坏模式,边坡的岩体结构及层间软弱夹层一起构成控制边坡变形的主要因素。基于以上的分析,边坡治理措施将重点放在控制软弱夹层与节理裂隙面的变形上。

The slope of Zhongshan to Majiang section along Guiwu Expressway have the slippage in the third-step slope. The field engineering geological conditions of a bedding rock slope are investigated and found in rock masses a set of mutually orthogonal conjugate joints and multilayer bedding weak layer. Then the types of rock mass structures and the combination between structural planes and slope surface and various excavation conditions are studied in detail so as to analyze the bedding slope deformation mechanism and the optimal supporting conditions. The result indicates that bedding weak layer and rock mass structure controls the types of slope deformation,and the present deformation is included in the beginning of the failure type of ＂overturning and creep-fracture＂. Slope reinforcement based on the analysis of deformation mechanism focuses on controlling the distortion of Joints and fissures structural plane and bedding weak layer and proper excavation conditions.