Study On The Deformation Mechanism Of The Steep Inclined Transverse Rock Slope In The Yellow River Cihaxia Hydropower Station Dam Area

Large water conservancy and hydropower projects are faced with a more severe problem of reservoir bank stability,a detailed understanding of the deformation and deformation mechanism of the reservoir bank slope,it is conducive to the analysis of its stability and its deformation and evolution trend.This article on the Yellow River Ciha Gorge Hydropower Station Dam Area steep transverse rock slope development of unstable body(II # landslide,3# deformation body and outlet slope deformation body inclination)as the research object,clarifies the basic geological environmental conditions,a detailed study of the typical slope in the study area boundary condition,the deformation and failure characteristics,combined with the numerical simulation of the deformation mechanism of the system analysis.The following rules and conclusions are obtained:(1)In the study area slope surface is developed,which layer fracture and dislocation with the development.Secondly,Shunhe to dip slope outside surface of the structure and the steep and in slow tilt structure have different degrees of dominance development.(2)In the study area deformation body and the deformation and failure of the landslide boundary obviously,much to fault belt or preferred structural plane as the main control boundary control outside the boundaries of the slope body is broken,the disintegration and rock longitudinal wave speed is low,usually located below 1500 m / S;within,the rock mass integrity increased rapidly and maintained at a higher level,rock compressional velocity is higher,usually in more than 2500m/s.? # landslide boundary for airport exposed conditions at the bottom of the flat slope structural plane,trailing edge with steep dip structural plane slip or crack boundaries,both sides in order to shun layer by layer sandwich,extrusion or lithological contact surface control.3# deformation body and the outlet of the slope deformation body in gentle dip slope fault as the bottom boundary slip,due to the bottom of the fault is not with the surface connectivity,front lock solid rock;trailing edge with steep dip slope tension crack zone and the weak surface for the boundary control;two sides of the same to interlayer faults and bedding planes as both sides of the control boundary.(3)Study of the typical slope deformation failure features:(1)The slope surface rock along the steep dip structure of surface slope unloading tensile deformation;(2)Slope in the upper part of the deep deformation failure mainly as cracking,overhead and collapse;(3)Slope at the bottom of the deep deformation damage in addition to the overhead,the collapse of the outer,but also crushed crushing is obvious by squeezing deformation characteristics of sandstone is generally,slate is crumpled or deflection.(4)Study area steep inclination horizontal rock slope deformation damage factors mainly: topography,lithology and slope body structure,structural plane and the airport surface combination,water.Combined with boundary condition and the deformation and failure characteristics of II # landslide and 3# deformation deformation mechanism and genetic mechanism of the body,a drainage slope deformation body are analyzed,according to the three bottom interface slip whether with slope surface connected,the slope is mainly divided into two kinds of deformation mechanism,a typical sliding tension type II # landslide,a is to 3# deformation and drainage slope is a typical slip shearing type deformation.(5)By three-dimensional discrete element method(3DEC)numerical analysis method,deformation of the study area typical adverse geological body II # landslide and 3# body as the research object.II # slope by deformation accumulation to sliding failure simulated the whole process.The results show that the slope first along the gently dipping slope structure slip,and the rear of the slope body tension crack development and the consequent expansion,eventually trailing edge of tension cracks and bottom slip surface through landslide formation.The deformation process of 3# is simulated.The simulation results show that: under the condition of mechanical parameters,the 3# deformation body is in a stable state and will not be unstable.In order to understand the 3# possible failure process,also in order to simulate the lock fixed section of mechanical parameters of rock mass deterioration process.In the initial stability calculation,lock on the solid rock mechanical parameters are reduced,when the reduction factor is 0.7,lock solid rock mass deformation gradually accumulate,also slope in the upper tensile crack development a lot,but also maintained a intact rock mass structure in deformation.Finally,with lock solid rock shearing failure,slope slip instability.Displacement monitoring of the monitoring results show that the sliding tension type in the middle of the slope displacement is the biggest,and posterior margin of the rock mass is obvious characteristics of the crack,and leading edge of rock mass is extruded bed characteristics,slope sliding failure after disassembly.Slip shearing type,from the trailing edge to the front,displacement decreases gradually showed obvious extrusion goes on,front blocked characteristics,lock solid rock cut,displacement increased rapidly to a stable values.