Study On Ground Movement And Deformation Of 90102 And 90103 Working Face Of AnTaiBao Coal Mine

With the quick development of our national economy,more and more resources are needed in developing economy, especially the coal resource. It is a highly serious problem of geotechnical engineering that underground mining arouse terrane movement and ground subsidence, which, at the same time, causes a great deal of ground fissure from coal mining. For the sake of mining safety, the rules of ground collapse and fissure distribution are really necessary to be researched.In this thesis, the rule of surface movement which is caused by the exploitation of faces of 90102 and 90103 of AnTaiBao coal mine is researched with FLAC3D. According to the actual exploitation process, the exploitation is simulated step by step. The numerical simulation result indicates that the maximum ground settling amount is 9.79m; the average radius of influence is 100.7m; the subsidence factor is 0.8; the tangent of major influence angle is 2.1; the mining influence spread angle is 87.3°; the horizontal movement coefficient is 0.24. Some results above are compared with the calculation results of probability integration method, which proves the reliability of calculation results of this thesis.In order to get the growth rule of ground fissure from coal mining, 10m as one step and 6mm/m horizontal deformation isopleth as the primary symbol, the growth rule of ground horizontal deformation in the area of 90102 mine face is simulated. The simulation results indicate that the closing cracks probably appear in the area between the 6mm/m horizontal deformation isopleth and working face during the process of exploitation and the width of closing cracks gradually decrease during the late stage of the exploitation of the 90102 mine face; the open fractures usually appear in the area between the 6mm/m horizontal deformation isopleth and the outer margin of 90102 mine face, at the end of exploitation, we can see the evolution of open fractures into transfixion. Besides, the open fractures appear after the closing cracks, most of the time of the exploitation, two kinds of cracks work on the ground surface at the same time, and both are affected by terrain.