Survey And Stability Analysis Of Goaf In Tongkeng Mine

With the continuous exploitation of mine resources,many underground mining mines in China have entered a deep mining stage,the continuous mining activities cause many mined out areas.Especially for historical reasons,unscientific mining and illegal mining in some mines have caused frequent mine accidents.Taking the underground goaf of Tongkeng mining industry with a mining history of more than 30 years as the research object,this thesis systematically combs the underground mining status and technical conditions of Tongkeng mining industry,analyzes the goaf generation and treatment results,and obtains the existing goaf objects to be detected,and adopts advanced hptem-18 high-precision transient electromagnetic system and CMS goaf detection equipment,Combined with three-dimensional numerical simulation,the underground goaf investigation and stability analysis of Tongkeng mining are carried out.（1）Using hptem-18 high-precision transient electromagnetic system,geophysical exploration and inversion of 18 survey points are carried out in different sections and regions.According to the detection data,there are mainly two abnormal phenomena in the unknown area at present,that is,the variation area from high resistivity to low resistivity.This phenomenon is mainly due to the conditions of high moisture content of loose body or ponding at the bottom of roadway.Compared with the mining status map and caving filling zoning map,there are roadway engineering or caving body in this area;Or the variation area from low resistance area to high resistance area,which is mainly caused by the non-compactness of local collapse loose body.（2）In this study,CMS is used to accurately detect the goaf of Tongkeng Mine,which not only accurately obtains the three-dimensional shape of the goaf and establishes the three-dimensional model of the goaf,but also accurately obtains the volume,roof area and The relevant information about the goaf,such as the actual boundary and goaf profile,provides the basis for the subsequent stability analysis and numerical simulation of the mine,and lays an important foundation for the safety management and control of goaf and resource mining.（3）The digital grid model of underground goaf（t6-1）in Tongkeng mining is established by using FLAC^3Dsoftware.The actual model of t6-1 goaf is established according to CMS goaf scanner,and three-dimensional numerical simulation calculation is carried out.The calculation results show that interval mining and timely filling can effectively control ground pressure and ensure mining safety.At the same time,in order to ensure the safety and stability of the lower stope,the thickness of the safety isolation roof should be more than 10m,and it is recommended to be about 12m.