Research On The Slope Stability Of The Tunnel Entrance

Tunnel engineering has intense relation with slope, the slippage of the tunnel entrance slope is one of the familiar geology disasters of tunnel under construction. As the safe stability of the tunnel entrance slope relate to how can enter the hole safety and carry on the construction smoothly, it has been come to be a important problem which the tunnel engineers pay much more attention to.The purpose of this paper is that study the successful experience of the former side slope stability analysis methods, through the data sorting analysis, get a summarization of the tunnel construction method, the slope constitution form and failure pattern;Imitates the slope failure pattern, compute the safe coefficient of slope stability with FEM, and put forward investigating opinion for the slope failure pattern and applicability of the Strength Reduction FEM in actual tunnel engineering .This thesis mainly is divided into five parts, the first part is mainly discuss the textual research present condition, the research purpose, method and contents;The second part is mainly summary the classification of tunnel entrance construction method and the establish type of entrance slope;The third part according to two kinds of different geology circumstance, considering the construction method, the tunnel structure and the type of tunnel entrance slope, research the slope stability influence factor and the falure mechanism mode;First the four-part carries on the simple introduction to the operation of a procedure ANSYS, then use FEM to imitate the slope failure mechanism mode and compute the safe coefficient of the side and on-head slope on tunnel entrance;The fifth part carries on a calculation to the left line of Ping-nian tunnel in Yunnan, contrast analysis result with actual engineering and put forward the related conclusion. Finally put forward this topic to gain the conclusion, and carry on the discussion to the concerning further work direction.