Research On Open-pit Slope Stability Of Xinjiang Tiyier Gold Mine

The stability of the slope has a direct influence on the safety and economic benefit of open-pit mine.If there are problems in the stability of the slope,it will increase the difficulty of mine exploitation and safety management of slope.The object of this study-Xinjiang Tiyier gold mine-is in the construction period now.Based on the consideration of serving mine production and the future slope management work,it is necessary to study about the stability of the rock slope in this mine.This study use a method combined of field investigation,experiment and theoretical study.Firstly,the engineering geology,hydrogeological features and structural plane distribution of the slope rock are identified through field investigation and experiment,which reveals that two main factors influence the stability of final slope possibly.One is groundwater in slope rock mass and the other is the soft rock-schistose tuff-in the slope rock mass of zone C.According to these two factors,on the one hand,this paper obtain the groundwater pressure distribution through the groundwater seepage in the rock mass of slope,and get the factor of safety of the slope in the case of groundwater in every zones by limit equilibrium analysis.By comparing the factors of safety of the slope in water state and anhydrous state,the effect of groundwater factor and the slope stability is analyzed.On the other hand,for the soft rock in the zone C,this paper has established a numerical model by FLAC3D,and analyzed the development of displacement and shear strain during the process of slope excavation.Finally,through the above analysis,the engineering protection measures are put forward for the problems of slope stability.Through the limit equilibrium analysis,it can be said that the influence of groundwater on the slope stability of A,B,D and E is limited-after taking into account the groundwater,the slope safety factor is reduced by 0.034?0.41,which indicated that the groundwater was not decisive for the factor of slope in these zones.Due to the presence of soft rock-schistose tuff,the slope in zone C is affected by groundwater more largely,whose factor of safety reduces 0.155 to 1.074 and is less than the minimum safety factor requirements.Though FLAC3D numerical simulation of the zone C,and the factor safety of the slope of zone C calculated by the strength reduction method is 1.11,which was close to the results of the calculation of the limit equilibrium method(1.074).The change of maximum unbalance force of the mining process shows that the excavation of the following steps under the 564m disturb the rock mass of the slope stronger than the previous steps.The change of displacement and shear strain increment show that the displacement of the rock mass is gradually increasing and shear strain is gradually concentrating from the beginning of the 540m step mining,which would eventually form a circular sliding failure.After studying the stability of the slope,this paper put forward measures of cutting slope,waterproof drainage and controlling blasting,which has good directive significance for mine production and slope management.