Study On Losing Stability Mechanics Of Counter-tilt Layered Rock Slopes

Bedded slope is common in the rock slope, the main rock types of sedimentary rocks and metamorphic rocks, such as limestone, SLATE, schist and phyllite, etc. Bedded slope including tended to shun and the slope. Conventional wisdom suggests countertendency slope is stable, however qinba mountains mainly palaeozoic group metamorphic rocks outcropped strata, in ankang, god river, mountain outcropped strata are mainly quartz schist, calcareous SLATE, sandy phyllite, the rock mass strength is low, the structure is broken, thus countertendency slope failure occurs frequently in the region. At present, this kind of slope failure mode, failure mechanism research is relatively weak. Engineering practice shows that the tendency of slope in the event of failure, will have serious engineering disasters.Generally will be the destruction of the layered rock slope is the tendency to type divided into sliding and dumping of two basic modes, and according to field investigation and geological exploration, most of the tendency of rock slope failure mode cannot distinguish for sliding failure or dumping of destruction, and the slope destruction form is complicated. Therefore, this article in view of the stratified countertendency slope instability problem research, numerical model and the means of combining theoretical analysis, analyze the failure mode, and its failure mechanism.In this paper, based on the finite element model of joint strength subtraction, the model takes into account the surface properties and structure of the rocks, also considering the yield shear stress and tensile stress yield; Finite element calculation with Phase2 finite element software as the platform, with typical phyllite countertendency slope as the research object, on the rock mass idealized hypothesis, which holds that by layered rock slope rock mass and the structural plane of rock mass structure surface evenly divided, rock is a homogeneous isotropic continuous ideal elastic-plastic body; To simulate the slope Angle, strata dip Angle, slope height elements such as change of countertendency slope failure characteristics. Established by studying the tension failure and flexural failure criteria and sliding failure criteria and titling failure mode. The layered rock slope is the tendency to failure mode is divided into five types: sliding failure mode, the slope slip- dumping in failure mode of the slope, the lower sliding- upper dump failure mode, the dumping of failure mode, slope sliding inside- outside dump slope failure mode, and put forward prevention and control of a guideline based on the failure mode.