Study On Contact Surface Effect Of Geological Disasters Occurred In Loess Slopes Area

Loess slope is one of the most important landform, which pregnant with geological disasters in the loess ridge area, loess Yuan area and loess lapin area. The morphology, occurrence and mechanical properties of the contact surface in loess-rock slope determine the macro mechanical properties and stress distribution largely. These control the mechanism of slope evolution. To make a further study, we take Gansu loess slope as the main research object, summing up the specific classification of contact surface’s morphology, and occurrence. Then we take the loess-rock contact surface as a example, using the bottom friction model test to explore the corresponding characteristics of loess slope deformation and failure, finally applying numerical calculation method to discuss the interface effect of loess slope geological disasters. All of these research results provide theory basis for this kind of slope stability evaluation and engineering measures.The main research results of this article are as follows:(1) Adopted the method of indoor model test to explore the deformation and failure characteristics of loess-rock slope, which have the different contact surface forms and occurrences. Taking no account of the external cause’s interference, we found that three kinds of contact surface(dentate, under convex and concave type respectively) has a kind of regularity differentiation characteristics about the whole process of slope deformation and failure. With the occurrence by tilting gradually converted to pour in, the deformation and failure characteristics of slope with the same interface form also has regularity characteristic too.(2) In this paper, through a large number of numerical model test verified the accuracy of the physical model test. We outline the effect of the contact surface of the loess slope on the slope deformation and destruction forms. Discussed in this article on the contact form including convex, undercut and dentate. In the process of slope deformation, the different contact point in the same contact surface,the corresponding contact point with different contact slope and the stress distribution and concentration in different parts of the same slope are different.(3) In this paper, we outlined the application of numerical model test contact the occurrence of the slope deformation damage effect. The occurrence of contact surface including three kinds-insides, outside and level respectively, each major category also covered different change of dip angle.We found that The occurrence and form of the contact surface have combined actions. The relationship between the local hypotenuse of contact surface and the attitude of rock changed the slope damage characteristics in localization stage, thus affecting the entire form of slope deformation and destruction.