Research On Fault Technology On The Fully Mechanized Working Face In Steeply Dipping Seam

The coal seam with large dip angle is basically formed by the strong crustal movement of the horizontal or near horizontal coal seam of the original deposition.Fault structure(i.e.fault)is common in coal seam with large dip angle.Fault,dip angle and coal thickness are the three key factors for safe and efficient coal mining.The superposition of large dip angle,many faults and high mining height increases the mining difficulty of coal seam,with many potential safety hazards,low output and poor efficiency.This paper is devoted to the study of mining technology of large dip complex coal seam encountering faults,This paper studies the key technology of stable control of support in normal mining of long wall face with large dip and thick coal seam strike without fault.This paper mainly studies the safe mining technology through faults,aiming to provide reference for the safe and efficient mining of such coal seam.(1)The results show that the fault activation mechanism and influencing factors:when the working face moves from the footwall of the fault to the fault,the normal stress of the fault decreases,the shear stress of the fault increases,and the fault is easy to be "activated" under the influence of mining;the influence of the fault activation slip is mainly determined by the fault dip angle,the additional shear stress of the fault mining increases,the normal stress decreases,and the properties of the fault and surrounding rock;when the coal seam with large dip angle meets the fault,the fault The integrity of rock mass in the area of strata is destroyed,and the deformation,destruction and migration characteristics of the roof near the fracture zone are more active,especially in the contact fault fracture zone of the roof strata in the middle and upper part of the inclined working face.The contact and loading characteristics of the roof and support in this area are more complex,and the stability control of the support sytem is more difficult;(2)Combined with the results of similar simulation and numerical simulation,it can be seen that the distribution of stress,displacement and plastic area in the face when encountering a fault of 10-15m increases greatly.This position has reached the main influence area of the fault on the face.The safety production measures of the face should be enhanced within the range of about 10-15m encountering the fault.At the same time,after crossing the fault,the support effect and personnel management of the face should be strengthened The purpose of ensuring safe,efficient and stable production of working face.(3)This paper studies the causes of stable control failure of support in 6152 fully mechanized face of Huashan coal mine due to fault,including too large fault distance,too large mining height,too heavy support,roof falling in front of the support,no anti slip device installed,side protection inversion and failure,improper operation of the support.At the same time,taking 6143 fully mechanized coal face of Huashan coal mine as an example,this paper studies the determination of abnormal area by fixed-point method,the reinforcement of roof and rock wall near the fault by advance grouting,and the special technologies of coal(rock),support,anti-skid,anti flying stone and support control during the period of passing the fault.