The Disaster Mechanism And Risk Assessment Of Rock Slope With Steep Dip- Angle

With the continuous development of the highway in mountainous area, rock slope with steep dip-angle become more and more common, and its Disaster Mechanism is complex owing to its influence factors:topography, geological characteristics, rainfall and so on. In real construction project, Often because of not understanding the forming mechanism and lead to the failure of protective engineering. As a result, the further research in Disaster Mechanism of rock slope with steep dip-angle has important significance on risk assessment, prevention and landslide treatment engineering of rock slope with steep dip-angle.Based on the landslide engineering at Qi wan highway K24+800, this paper has a In-depth study in disaster mechanism and risk assessment of rock slope with steep dip-angle by means of theoretical analysis and numerical simulation method and the results obtained are as follows:①Combined with several common types of rock slope damage, the paper summarizes the factors influencing the stability of rock slope with steep dip-angle, analysis the basic failure mode, plane stress state, disaster mechanism of rock slope with steep dip-angle, and consider the slip-bending damage, or called the yield of destruction, and divide its disaster process into four stage:unloading rebound, crack, extrusion bending and sliding failure②Taking landslide engineering at Qi wan highway K24+800 as background, the paper has a systematic analysis of the hydrogeological conditions of the landslide zone, and describes the deformation characteristics and structure characteristics of the landslide, then analyzed the reason of deformation and failure.③Selecting the most typical section of landslide Ⅲ-Ⅲ, the paper simulate the process of its disaster by UDEC-a distinct element program. Through comprehensive analysis on pictures of the slope’s maximum unbalanced force, velocity vector, displacement vector, stress, plastic zone distribution under different Calculation cycle, and summed up that shear failure is the main reason for the destruction of rock slope with steep dip-angle:because the upper rock mass along the weak plane sliding failure led to the lower part of the bending extrusion (shear) failure of rock mass, and finally cause the whole slope instability.④Based on the theory of fuzzy mathematics, the paper select the appropriate evaluation index, and established two grade fuzzy comprehensive evaluation model of the rock slope, taking landslide engineering at Qi wan highway K24+800 as background, assess its risk and the final evaluation results for model is Ⅳ. The results fit well with actual project, which has a certain guiding significance.