In-situ Leaching Mine Internal Force Monitoring And Analysis And Calculation Of Critical Liquid Injection Area

This paper considers ion-absorbed rare earth mines with in-situ leaching process as the research object.In view of the potential problems of slope instability during the process of leaching,field monitoring and research are carried out,which is of great significance for the safe exploitation of the ion-absorbed rare earth.The boundary between the upper liquid injection mountain and the lower anti slide mountain is defined as the last row of the injection hole along the slope down to 1.5 m?2 m,and at the same time,'retailing wall' is defined as the plane of the boundary along the depth.A number of earth pressure sensors,moisture sensors,liquid level sensors and displacement sensors are arranged in the testing area to monitor the water level changes,stress and slope deformation during the leaching process.Obtaining the physical properties and strength parameters of the ore body from the test site,and then the distribution and variation rule of the slide force of the upper liquid injection mountain and the anti slip force of the lower uninjected mountain under the liquid injection area of about 40%and the single hole injection strength 0.9 m3/d are analyzed.On this basis,theoretical analysis and GeoStudio numerical simulation software are used to calculate the critical liquid injection area of the test mine.The main conclusions of this paper are as follows:(1)The recovery rate of the solution in the test mine is 70.15%.After 75 days,the seepage stability is basically achieved.The water level of the mine is greatly influenced by the topography and the intensity of liquid injection.After the seepage is stable,the water level is basically the same.(2)There is a semi logarithmic linear negative correlation between the cohesive force of c and volumetric water content theta,and the internal friction angle has little effect on the change of volume moisture content theta.(3)The upper liquid injection mountain has a linear distribution on the earth pressure intensity of the 'retaining wall' along the depth direction,and the hear strength of the potential sliding surface in the lower anti slide mountain is power function distribution:the shear strength decreases with distance increases.(4)The calculation shows that the slide force of the line 1 is 220.50 kN,and the maximum anti slip force is 765.13 kN.At the same time,the slide force of the line 2 is 270.17 kN,and the maximum anti slip force is 398.84 kN.The maximum anti slide force is more abundant than the slide force.(5)In the actual production of the process of in-situ leaching,the mine has a good stability in the whole.Under the condition of the single hole injection strength 0.91m3/d,the results of theoretical calculation show that the critical liquid injection area of the mine is 73.26%,and the critical liquid injection area of the test mine is 70%through the GeoStudio numerical simulation.The resultant error of the 2 methods is only 4.66%,which proves that the calculation results are reliable.