Stability Analysis And Evaluation Of Soil Slope System With Shear Dilation Effect Considered

Soil body has dilatancy character more or less, but dilatancy has obvious effect on the force、deformation and stability of soil, so dilatancy should be used and evaluated reasonably in practical engineering. For simple or for conservative, we often set the value of dilation angle to zero (non-associated flow rule),which ignore the dilatancy of soil completely in slope stability analysis at present.It is generally accepted that it is conservative to set the value of dilation angle to zero. For example, the safety factor is usually the minimal if we set the value of dilation angle to zero in soil slope stability analysis. It is important but not comprehensive to evaluate slope stability from the perspective of safety factor, so the result is not necessarily reliable. In order to obtain a more comprehensive and reliable conclusion, the paper mainly focus on soil slope system and analyze its stability comprehensively from the perspectives of safety factor、 the deformation behavior under loading of soil, the force of anti-slide pile and retaining structure.The paper mainly study the following research work:(1) Effect of dilation angle on slope stability. Now about the effect of dilation angle on the safety factor of slope have two views. One is the slope safety factor increases with the increase of dilation angle. The other view is that with the increase of dilation angle, relationship between safety factor and dilation angle presents the discipline like parabola curve, first increases then decreases. We verified the two views first and explain why the other view is wrong. Meanwhile we pointed out the limitation of strength reduction method on slope stability analysis.(2)Then we use the finite element software ABAQUS to simulate the effect of dilation angle on the safety factor of different forms of slope without reinforcement.(3) We utilize ABAQUS to create a3-D slope model stabilized by anti-slide pile, a model stabilized by retaining wall, a3-D slope model stabilized by anti-slide pile and retaining wall respectively, which were used to analyze the effect of dilation angle on safety factor, the deformation of the pile, the working status of anti-slide pile and retaining wall. Analyze and summarise the rationality of setting non-zero dilation angle to zero in all cases.The following innovative points were presented in this paper:(1) The paper verified the two views about the effect of dilation angle on slope stability and pointed out that strength reduction method has limitation on slope stability.(2) The paper studied the effect of dilation angle on the force of anti-slide pile and retaining wall, besides safety factor. The paper comprehensively analyzed the effect of dilation angle on the stability of slope system.The purpose of the paper is to provide a reference for engineers in the numerical simulation of slope stability. In other words, they should pay attention to the effect of dilation angle on slope stability.