Slope Stability Analysis For A Ionic Rare Earth Mine In-situ Leaching In Gannan Area

As the main producing areas of south china ion-absorbed rare earth ore, rare earth of gannan accountes for 30% of the whole reserves. In the exploitation of ion-absorbed rare earth ore,in-situ leaching mining process is widely used.Affected by the engineering properties of rare earth and mining methods,it is easily lead to slope instability. Therefore, it is necessary to study the rare earth ore slope instability.In this paper, the research object is the slope of ganxian rare earth ore.The physical properties of rare earth soil was carried out under the indoor simulated immersion test.The influence factor of slope stability is analyzed by using the orthogonal test method; In situ leaching mining, numerical simulation method is used to anlyse the distribution of liquid injection and the slope stability under seepage; The measures of rare earth slope protection is instroduced. Draw the following conclusions:1.The soil physical properties in rare earth ore leaching before and after is changed. After insitu leaching reaction, the average particle diameter of the soil samples changed little, but the fine clay is reduced more. Before and after leaching, the density changes little. After leaching, the permeability factor increases ten times. With the increase of leaching time,cohesion is decreased and internal friction angle is increased,both all finally tend to a stable value.2.A slope calculation model is set up.In the natural state and after leaching,the slope is in stable or the basic steady state and does not produce damage, only the safety factor dropped slightly.3.The influencing sequence of slope stability factor of ion-absorbed rare earth ore is slope angel, cohesion, internal friction angle, slope height. Slope angel is greater than the other three factors on influence degree of slope.4.The safety factor of ion-absorbed rare earth ore increases with the injection time. On the whole it is stable and reduced after the twentieth day. Injection of first to fifteenth days, the safety factor does not change significantly and is greater than 1.1. It is stability.When the time of the liquid injection is continued until the 20 th day, the stability factor is decreased rapidly. On the twenty-third day, the safety factor of the slope has been less than 1.05.And the slope has been destroyed at this time.