Stability analysis for jointed rock slope in an open iron ore mine

According to the structure characteristics of the joint rock mass of the east slope of Gongchangling open iron ore mine,using the 3 dimensional rock non-contact measurement system (3GSM),the investigation and statistical a-nalysis of surface structure are performed. Detailed statistics data including surface structure tendency,inclination,joint trace length,and joints pitch are obtained. Based on Monte-Carlo stochastic simulation method,the three-dimensional network model of jointed rock mass is obtained by the structural network simulation software FracSim3D. The rock quality index RQD is obtained by drilling samples on the three-dimensional network model. Then the RMR index is evaluated combined with on-site point load test. The shear strength parameters of jointed rock mass are obtained by Hoek-Brown method. Jointed rock slope is modeled through the FISH language programming,and the stability of the slope using the discrete element software UDEC is performed. The results show that the slope is in a stable state,but the local wedge failure of rock mass occur in the upper areas of slope,which is controlled by the joints along slope di-rection. The phenomenon of block out also appears in dispersion zone.