Fast Goaf Forming Technology Of Deep Three Soft Coal Seams

With the increasing trend of coal consumption,the continuous exploitation of coal resources,and the declining coal resources in the shallow part,it is an inevitable trend for domestic mines to enter the state of deep coal mining.With the development of social economy,my country's coal mining technology and mechanical equipment have achieved rapid development,and the coal mining capacity of coal mining faces has also been improved.However,compared with the mining capacity,the speed of roadway formation is affected by the selection of construction equipment,construction organization and management,and construction technology,which obviously cannot meet the large demand for mining.Aiming at the problems of serious deformation of the surrounding rock along the gob in the three-soft coal seam of the deep mine,difficult support,and slow roadway formation speed,this paper takes the 1126(1)working face of Huainan Guqiao Mine as an engineering example.Through engineering geological survey,Related theoretical analysis,numerical simulation and similar simulation experiment methods are used to study the stress distribution and deformation and failure characteristics of the surrounding rock along the dynamic pressure roadway,and the failure mechanism is discussed,and the following conclusions are obtained:?The mechanical model of the key blocks of the overburden is established On the basis of the mechanical model of the coal pillar,the relevant structural parameters of the key rock strata B are calculated,and the stress distribution law of the coal pillar is analyzed.Finally,the reasonable retention of the narrow coal pillar along the track in the 1126(1)track of Guqiao Mine is initially obtained.Let the width be 8m.?Using the three-dimensional numerical simulation software FLAC3D to simulate the surrounding rock stress distribution and displacement when the narrow coal pillar is 4m,6m,8m,10m,12m,14m after mining at the previous stoping face,according to the design principle of the narrow coal pillar along the goaf roadway,According to the actual situation of the 1126(1)track along the track in Guqiao Mine,combined with theoretical calculations on the basis of numerical simulation,it is determined that the reasonable width of the 1126(1)narrow coal pillar is 8m.?It is proposed to optimize the support of 1126(1)track along the groove in the two aspects of reducing the length of the anchor cable and the distance of the anchor cable row,and analyze the feasibility of optimizing the support through numerical simulation.?Through similar simulation tests,it is found that the surrounding rock of the roadway has sunk as a whole,and the rock mass under the roadway is affected by horizontal squeezing and moved towards the mined-out area.The rotating movement of the cantilever beam above the goaf caused the overlying strata to shift to the right.The inner squeeze deformation of the two sides of the roadway,and the inner squeeze deformation of the right side is obviously greater than the inner squeeze deformation of the seat side,and asymmetric phenomenon occurs.Capacity,the roof of the goaf collapsed and compacted.?According to the 1126(1)track along the trough underground pressure observation,the roadway deformation is periodic,and the deformation time of the bottom heave and the two sides is basically the same.The deformation of the roof and floor of the roadway is dominated by the bottom heave,and the roof basically does not sink.The deformation of the left side of the two sides is larger than the solid coal side of the right side.The optimized support scheme still effectively suppresses the deformation of the roadway,ensures the safety and reliability of roadway driving along the goaf,and realizes rapid roadway completion.The research results of this paper reveal the temporal and spatial evolution law of surrounding rock stress,deformation and plastic zone of roadway driving along goaf,which provides theoretical and technical reference for the rapid roadway formation problem of this kind,and ensures the safe and efficient mining work of 1126(1)working face.Figure 66 Table 13 Reference 70...