The Gradual Destruction Mechanical Model And Time-dependent Deformation Analysis Of Landslide With Double Sliding Planes & Rock-layer Reverse

The landslides we study are those with double sliding plane and reverse rock-layer. The interaction of the two sliding planes and the anti-sliding function of the reverse foreside make them have special deformation and failure mechanism. Little work has been done to study the deformation and failure mechanism of these landslides. Study on this kind of landslide has important value of theoretical research and realistic significance of engineering instruction. It has also important reference values for the landslide of double (multi-) sliding planes, the landslide of rock-layer reverse, the landslide of slumping and curving collapse yield, the falling landslide, etc. So, it is in urgent need of developing some correlative researches on this kind of landslide.This paper takes the example of HanJiaYa landslide in Xiangshi Expressway, which has the representative characteristics of the landslide with double sliding planes & rock-layer reverse. Based on the study of the basic characters, formation conditions, hazard mechanism and structure features of the landslide, this thesis deeply analyzes the gradual deformation and failure mechanism of"double plane creeping slide-reverse rock-layer deformation-bending break-slope sliding"of the landslide. According to the qualitative analysis of gradual destruction process of the landslide, this thesis sets up the mechanics models-congruence beams and multi-layer thin plates, puts forward the relative stability evaluation principle and gives critical shear strength of the sliding plane when the whole landslide starts in motion. Comparing the deducted results of mechanical model with those of laboratory model test, we can draw the conclusion that the above mentioned mechanical models can qualitatively estimate the embedding depth in the process of landslide expansion and the critical shear strength of the sliding plane when the whole landslide starts in motion and at the same time, the models can qualitatively analyze the gradual destruction process of the landslide. Through the deep exploration of bending creep mechanism of reverse rock-layer and the relative influencing factors and through the combination with deformation equation of congruence beams and multi-layer thin plates, this thesis puts forward the time-dependent deformation equations concerning the bending creep of rock layer and suggests a clue to forecast the slope sliding according to the deformation rate of bending creep of reverse rock-layers. The thesis establishes creep buckling equation of reverse rock layers under the condition of plane strain and analyzes creep buckling instability mechanism and detention destruction characteristic under different load levels.Combined with the method of strength reduction, the software of FLAC3D is used to analyze the deformation destruction course of the landslide and the comparison is made with the analysis of mechanics model. This thesis explores the existing criterion of...