Study On The Application Of Soil Nailing In Loess Slope

In this thesis, a field cutting loess slope was studied, which is located in the open cut segment of Han Guguan tunnel exit of Zheng-xi railway Line for passenger traffic. By the analysis systematically for the loess characteristics and the survey for the construction site slope failure examples, the engineering geologic condition of the field was illustrated, and the local unstable failure model was proposed. Based on the numerical analysis computation, the stability and its soil nailing investigation for the field cutting loess slope was carried out.Based on the domestic and foreign literature and data, the status and development of the investigation of the slope stability and soil nailing supporting were summarized, and the universal analysis methods of slope stability and the mechanism of soil nailing supporting at present were generalized, and to discuss in detail the physical mechanics properties of loess, especially for the joint properties of loess.On the basis of the engineering geologic condition of the field, the collapse feature and cause of the cutting slope were analyzed in detail, and the geologic failure model of the cutting slope was established.According to the geologic failure model of the cutting slope, and the design specifications referred to the codes of railway and highway for the loess cutting slope and its soil nailing supporting , the numerical analysis models were proposed. By the numerical simulation analysis method of Flac, the characteristics of the loess cutting slope and its soil nailing supporting, the displacement changing law of the cutting slope and the tensile stress distributing law of the soil nailing were analyzed, the cutting reasonable slope shape, ratio of the loess cutting slope, and the well parameters of the soil nailing supporting were determined.Based on the, to analyze the cutting slope displacement and deformation of soil nailing axial stress changes in the law , receive the slope excavation reasonable slope shape, slope excavation and reasonable than the soil nailing parameters, in the loess areas.In brief, the critical influence factor of the loess cutting slope stability were as follows: the physical mechanics properties of loess, slope shape, excavation depth, joint position, joint unloading depth, supporting ways and so on.