Numerical Analysis Of The Stability Of Jointed Rock Slopes Based On DEM

In civil engineering, jointed rock slope stability analysis is a very important problem. The field include in highway, railway, hydraulic engineering, mining, et. Because of the complexity of its stress and geological condition, the failure course and influencing factor of jointed rock slope is hard to confirm by theoretical method accurately. At present, there is no perfect way to analyse the stability of complex jointed rock slope, the traditional limit equilibrium method searches through the circular slip surface is not suitable. Although other numerical methods can calculate slope of the stress, displacement, plastic zone, etc., but are based on the ideological continuum,the reliability of the results depends on the approach extent of real condition.As a complex geological, jointed rock slope is a discontinuous media. The mechanical property, stress condition and displacement rule vary in different place. PFC2D, based on the discrete element method, was introduced to simulate the deformation of jointed rock slopes, without considering constitutive relation of material and assuming slip shape, directly defining contact relation between particles microscopic view. The calculation of the program is natural adjustment progress of inner material to get stabilization in rock slope, without satisfying displacement continuum and deformation compatibility condition. It can describe visibly the slipping of slope, the development of the crack, and the geometric shape and position of slip plane.The complete rock and jointed rock mass model was established using PFC2D, then, using plane strain test model to calibration macroscopic mechanical parameters, by adjusting the microscopic parameters of jointed rock mass model,match the real material mechanics parameters. A general study on the rock slope containing two coplanar through joints and several discontinuous joints was carried out,the joints distribution forms that influence the slope stability and failure mode was analyse qualitatively. The stability safety factor calculation method based on DEM was proposed tentatively,and the result was compared with the finite element numerical example. Using the monitoring mechanism in PFC2D to record the stress changes in different position of slope,then find the relationship between stress variation and the jointed rock slope failure mechanism.