Study On The Regularity Of Surface Movement Caused By Shallow Seam Mining

With the development of society, the demand for energy increasing, coal resources is themain source of energy.Due to the exploitation of underground minerals,coal seam mining notonly causes surface dehiscence,deformation, damages buildings and accelerates the process ofsoil erosion, but also induces landslide, collapse and many other geological disasters, greatlyaffected the people’s production and living,it has become one of the important research topicsof Geotechnical Engineering.Shallow coal seam mining induced ground movement is a complex time-spatialprocess,sure the deformation value of the different points on suface in the process of mining,and it is associated with the recovery rate and the relationship between miningmethod,predicting the distribution of the surface deformation, maximum deformation valueand when and where the maximum deformation of ground surface will appear which has thevery vital significance. Aiming at the deficiency of research on dynamic surfacemovement,put forward and deduced a function model on predicting the surface of threedimensional moving,we can call it"unit strip mining subsidence model".There have a contactbetween the time after the unit strip mining and the time of the working face advancing(orstaying),can better predict the sink and sinking speed at any point in any time of thesurface,comparison with the field data analysis shows that this model can better reflect thedynamic movement of the each point of the surface, which provides a theoretical method forthe parameter selection of probability integral.In order to study the steady state characteristics of surface subsidence,on the basis ofanalysis of the overlying soil and rock layer movement regularity,put forward a kind ofestimation method on calculating the surface movement parameters when the surfacemovement stability, this method can predict the boundary angle and the subsidence coefficientbefore mining, engineering examples show that its expected result is accordance with the test result.Based on a practical project of N1201working face mining in Ning tiaota coal mine asthe background,numerical simulation analysis is maded by FLAC3D,in order to consider theterrain effect on the ground surface movement, to establish a real3D geological model.Numerical results and the measured results are basically the same, it shows through thenumerical simulation of the surface movement in research of surface movement are expectedto be an effective means.