Analysis Of Geostress Measurement Results And Stress Distribution Status In Jinchuan No.3 Mining Area

Since the discovery of the Jinchuan mining area,the development of faults,joints,and fissures in the range has been very obvious,which indicates that the Jinchuan mining area has been affected by many tectonic movements in history.With the increase of mining depth in Jinchuan No.3 mining area,the existing underground safety engineering has entered a high geostress environment,and new deformation forms have appeared in the deformation of underground roadways,thus affecting the development of the mining area.Because the geostress is an important factor affecting the stability of underground safety engineering.Therefore,it is necessary to grasp the geostress characteristics and distribution rules of Jinchuan No.3 Mining Area in time,and propose reasonable suggestions for ensuring safe production for the mine.This paper relies on Jinchuan Group's key project “Deep Mining Technology Research in Jinchuan Mine—Deep geostress Testing Research”.Based on the collection and collation of the geological data of Jinchuan No.3 Mining Area and Jinchuan Integrated Mining Area,three horizontal sections of 1450 m,1330m and 1250 m were selected for the in-situ measurement of in-situ stress,the geostress of two horizontal sections of 1450 m and 1330 m was simulated.Through the above work,the following results were obtained:1.By analyzing the measured results of the in-situ stress of the Jinchuan No.3 mining area,the curve of the geostress with depth is obtained.It is concluded that the geostress characteristics of the Jinchuan No.3 mining area have a new form of change.The new geostress environment is the main factor causing damage to the underground safety engineering in the mining area.2.The results of simulation analysis show that the distribution of equivalent stress values in ore bodies is not uniform,which should be considered when carrying out underground safety engineering construction;obvious stress concentration is easy to occur at the junction of rock mass.3.The measurement results show that the maximum principal stress of the horizontal section from 1250 m to 1450 m in Jinchuan No.3 Mine is between 13.0MPa-18.6MPa,it belongs to medium stress level;the maximum principal stress direction is near north-south,northeast to near east and west.The difference of the three principal stresses is large(the main stress difference of each measuring point is between 3.7MPa-10.6MPa);the maximum principal stress of the horizontal section of 1250 m and the horizontal section of 1330 m is almost horizontal,showing horizontal stress as the dominant;the maximum principal stress inclination of the horizontal section of 1450 m is larger,this indicates that horizontal ground stress is not the dominant way of this horizontal segment.Through the analysis of the geostress measurement results and the stress distribution state of Jinchuan No.3 Mine,the influence of geostress on the deformation and failure of the roadway in the mining area is revealed,which can provide reference for the future underground safety engineering design and construction of Jinchuan No.3 Mine.