Research On Reasonable Retention Technology Of F14 Fault Waterproof Coal Pillar In 1012 Working Face Of Wugou Coal Mine

According to the relevant rules and regulations such as the Coal Mine Water Prevention and Control Regulations,in the process of coal mining,when a fault with a large drop is encountered,it is necessary to leave a fault protection pillar to ensure safe mining.If the width is too large,it will cause Loss of coal resources;if the width is too small,it will cause water and sand burst safety production accidents.The F14 fault has a drop of 10 m to 280 m,and the original design retains 80 m to 100 m,and presses more than400,000 tons of coal resources.The economic and technical rationality is questioned.Therefore,it is very necessary to carry out the research on the rational retention technology of F14 fault waterproof coal pillars.The thesis takes the 1012 working face near the F14 fault of Wugou Coal Mine as the research object.On the basis of consulting the domestic and foreign frontier technology of fault coal pillars,based on the ground three-dimensional seismic data,combined with the return air lane,-380 m south wing belt machine lane,-360 m horizontal south wing track laneway and other roadways,underground drilling Data such as exploration and surrounding borehole exposure systematically analyzed the F14 fault drop,water-rich features and swing patterns near the 1012 working face;rock samples of fault zones and coal roof and floor were taken for rock mechanics and hydraulic properties analysis tests On this basis,an engineering geological analysis model was constructed,and numerical simulation was performed using FLAC3 D.The following conclusions were obtained:(1)The 1012 working face is located under the F14 fault,and the main water damage factors are "four-containing" water and top and bottom sandstone fissure water 1.Floor limestone water and fault water,of which limestone water enters the working face through fault communication is the main safety hazard of safe mining in the 1012 working face;(2)For the F14 fault,4 drill fields were designed in 1012 wind lanes and 14 drills were constructed Holes,roadway exposure and downhole drilling results show that: F14 fault has a drop of 70 m in the west,100 m in the middle,and annihilation in the east;the water and water richness of the fault is poor and belongs to the Water-conducting and non-water-conducting faults;(3)10 coal roof overburden compressive strength is10-40 MPa,which is a medium-hard overburden type,with good barrier and water blocking capacity;(4)using FLAC3 D software The numerical simulation of 50 m and 30 m coal pillars was obtained,and the evolution characteristics of the corresponding stress and displacement fields were obtained.After theoretical calculation and comparison,the 30 mwidth F14 fault waterproof coal pillars were left,and the fault coal pillars were reduced by70 m,which Recovered 70,000 tons of coal,with obvious economic benefits;(5)Based on the mining technical conditions of the 1012 working face,practical countermeasures for the prevention and control of water damage in the 1012 working face were formulated,and the safety and economy of mining were carried out Analysis and evaluation.Figure [40] table [ 27] reference [60]...