Structural Analysis Of Overburden And Its Movement Law In Deep Mining In Tengxian Coal Field

In this paper,the horizontal project "study on lithology analysis and movement law of overburden rock in deep area of Xin'an coal mine" is taken as the engineering background.Through theoretical analysis,numerical simulation and field measurement and other methods,the "mud-sand" composite overburden structure of Tengxian coalfield is analyzed,and the results are as follows:(1)Based on the study of strata association and key strata theory,and combined with the actual situation of the 3406 working face of Xin'an coal mine,this paper analyzes the"mud-sand" composite overburden structure of Tengxian coalfield,and divides the overburden into four different strata associations.Rock combinations ?,consistis of the 3 layer of fine sandstone and the 4 layer of mudstone above the roof of the working face;Rock combinations ?consists of layer 5 of fine sandstone,layer 6 of mudstone,layer 7 of fine sandstone and layer 8 of mudstone;Rock combinationsIII,consists of layer 9 of fine sandstone,layer 10 of mudstone,layer 11 of siltstone and layer 12 of mudstone;Rock combinations?,consists of layer 13 of fine sandstone,layer 14 of mudstone,layer 15 of fine sandstone and layer 16 of mudstone.And the motion parameters of the immediate roof and the main roof are preliminarily calculated.After calculation,the first collapse step of the immediate roof is 31.2m,the first weighting step of the main roof is 5 1.3m,and the periodic weighting step is 17.1m.(2)Through Xin'an coal mine 3 coal strata rock mechanics experiment,and according to the test of the rock mechanics parameters and Xin'an coal mine actual geological condition of experiment work face,the calculation model is established and simulation study after working face mining roof movement.It is concluded that the first collapse step of the immediate roof is between 20 and 30m,the first weighting step of the main roof is between 40 and 50m,and the periodic weighting step is 17m.(3)According to field measurement,the test working face period can be used to calculate the minimum periodic weighting step distance of 16.1m and the maximum periodic weighting step distance of 17.5m.In order to solve the problem of advanced support,a kind of "Hydraulic Support with Frame Advance Support" is invented.