Study On Deep Engineering Geology And Mining Stability Technology Of Jinchuan Second Mining Area

After the Jinchuan No.2 mining area enters deep mining,it faces complex engineering geological conditions.The obvious difference between deep underground engineering and shallow engineering lies in the special environment("three highs and one disturbance")in which deep rocks are located,that is,high ground stress,high ground temperature,and high ground temperature.Osmotic pressure and mining disturbances.The deformation of the roadway rock mass is manifested as structural large deformation,discontinuous and uncoordinated deformation,etc.The further development of the deformation leads to the destruction of the rock mass,and engineering disasters such as spalling,roof falling and large area collapse and instability,which threaten the underground The life safety of operators.In order to ensure safe production,reduce mining costs,and provide technical guidance for the optimization of mining design,it is necessary to carry out engineering geology and stability research in the deep mining process of Jinchuan.This time,a combination of on-site investigation,physical mechanics experiment,on-site monitoring,numerical simulation,and mechanical analysis was used to systematically study the deep engineering geology and mining stability of the second mining area.The main research results are as follows:(1)The deep engineering geological conditions of the second mining area were ascertained,the rock physical and mechanical parameters were obtained through testing,and the rock mass quality classification evaluation was carried out.The RMR classification result is Grade III,and the Q system classification result is Grade IV.The integrity of the rock mass is poor,the horizontal stress is greater than the self-weight stress,and the weak structural plane is the main factor affecting the stability of the rock mass and engineering in the mining area.(2)Monitored and analyzed the range and change law of the loose circle of surrounding rock under deep mining conditions,the convergence and deformation law of the roadway support structure,the deformation mode and the deformation mechanism,based on the test roadway surrounding rock rock mechanics test,engineering geological survey and monitoring results,Judge the type of instability of the roadway rock mass structure,evaluate the mechanical strength of the surrounding rock mass of the roadway,the matching of the rock mass structure with the support design method and support strength..(3)The FLAC3D software was used to establish a numerical calculation model for the interaction between the surrounding rock and the support of the roadway,analyze the law of the interaction between the surrounding rock and the support of the roadway,evaluate the rationality of the existing roadway support design,and propose different types of roadways instability The most optimized support plan.(4)Establish a mechanical model and a physical model under the condition of pillar support in the stope.Study the strength damage law of the stope pillar under the action of the disturbed stress field,establish the mechanical type and the instability criterion of the single pillar instability,and propose the precursor indicators of the critical instability of the pillar and the reinforcement measures of the potential instability pillar.