Stability Study On The Slope Of Gold Mine At Eritrea Koka1

Open pit slope is one of the elements of the open pit mining field and slope engineering plays an important role in the open pit mining. Sometimes the ultimate slope angle of 1 degrees, the state can be stripped of the rock to reduce the amount of 10 million t or more, save the investment of tens of millions of yuan. At the same time, the open pit slope is one of the most dangerous sources of open pit mines. It is often seen the slope instability and the collapse of the disaster accident.So in the initial stage of the design of open pit slope stability and its optimization analysis is very important. Koka gold mine is a large open-pit mine, the final slope mining will be 280 meters which belongs to the field of high steep slope,it is necessary to analysis the slope stability. In this paper, based on Koka gold mine has some geological data and preliminary design data analysis, the stability analysis of the slope rock mass is carried out by using the limit equilibrium method, the finite element strength reduction method and the interior friction simulation test. Results are as follows:(1) According to the geological and topographical map, partitioned with a surface profile and using AUTOCAD software to create the slope model, and lay the foundation for slope stability analysis and slope angle optimization.(2) In accordance with national standards and test specification, processing the rock samples collected on the spot, and conduct uniaxial compressive test, finally get the rock slope of the elastic modulus and Poisson rate.(3)Using the limit equilibrium method to analyze the stability of the slope. The minimum safety factor of the slope is 1.46, the slope is in stable state and the national standard is met. And at the same time from the theory of Koka gold open pit slope ultimate slope angle are analyzed. The final slope angle is 47.5 degrees and the angle of the slope is 66 degrees.(4)Using the numerical simulation method, using ABQUAS software to establish a three-dimensional slope model, study the change of the stress and strain of the slope rock mass during excavation process, and use the strength reduction method to evaluate the slope stability. The shear stress and displacement of the horizontal direction of the slope are mainly concentrated in the slope. According to the strength reduction method, the safety factor of the slope is 1.25, which meets the design requirements.(5)By using the bottom friction test, study the stability of the slope and the potential failure mode of the slope and the slope stability. The results showed that the slope in the excavation process in local will collapse, but the whole slope in steady state, and final slope of open-pit mine slope angle with optimization 1~2 degrees to be.