[Procedures] Article 231 The arrangement and mining operations of mine ground pressure in mines shall comply with the following provisions:

When the (a) layer of coal mining impact pressure, can not be disposed in the stress concentration area of two simultaneously working face mining operations. When the distance between the two working faces is less than 150m, when the distance between the coal mining face and the heading face is less than 350m, when one of the two coal working faces is less than 500m, one of the working faces must be stopped. Mining interactions should be avoided between adjacent mines and adjacent mining areas.

(2) The open roadway shall not be placed in the coal seam with severe impact pressure, and the permanent chamber shall not be placed in the coal seam under impact pressure. The coal seam roadway and diverticulum layout should not be reserved for bottom coal. If the bottom coal is left, the floor preload relief measures must be taken.

(3) The roadway in the thick coal seam with severe impact pressure shall be arranged outside the stress concentration zone. When two lanes are driven, two parallel lanes should avoid mutual influence in time and space.

(4) Coal seams with impact pressure shall be mined in strict accordance with the order, and no island coal pillars shall be left. Coal pillars shall not be left in the goaf. If it is necessary to retain coal pillars in the goaf, it shall be demonstrated and reported to the technical person in charge of the enterprise for approval, and the position, size and influence range of the coal pillar shall be marked on the plan of the mining project. on. For the mining of silo coal pillars, the anti-shock safety mining demonstration shall be carried out; the island coal pillars shall not be mined in the severe impact ground pressure mine.

(5) to rockburst, a top substrate should be appropriate to increase the aisle width Driving of slate. The coal pillar-free roadway protection technology should be preferred, and the stress concentration zone should be avoided when using large coal pillars to protect the roadway. It is strictly forbidden to leave large coal pillars to affect adjacent layer mining. Rigid support is strictly prohibited in the roadway.

(6) When the roof is managed by the slump method, the bracket (column) shall have sufficient supporting strength, and all the pillars in the goaf shall be returned to the net.

(7) Special measures must be formulated when the impact mining face is close to large geological structures, goafs and other stress concentration areas.

(8) The anti-shock measures during the initial pressure, periodic pressure, and the “seeing” of the goaf shall be clearly specified in the operating procedures.

(9) When mining and recovering coal pillars in areas surrounded by goafs on three or four sides of non-impacted coal seams, special anti-shock measures must be formulated.

[Execution Description] (1) Stress is a necessary condition for the occurrence of impact ground pressure, and the mining activity will cause the stress distribution of the coal (rock) body to change and the degree of stress concentration to increase.

(2) Within the scope of the concentrated stress, if the two working faces are arranged at the same time, the supporting pressure of the two working faces will be superimposed, and the value will increase exponentially, which will easily induce the impact ground pressure. Therefore, in order to avoid the interference of the mining and excavation working face of the coal seam in time and space, there should be enough mining error between the working faces.

The distance between the two tunneling faces of the same roadway shall not be less than 150m (Fig. 9a), and the slant distance between the two tunneling faces of adjacent tunnels shall not be less than 150m (Fig. 9b). The distance between the adjacent tunneling face and the coal mining face shall not be less than 350m (Fig. 10a), and the slant distance between the adjacent tunneling face and the coal face shall not be less than 350m (Fig. 10b), adjacent to the tunneling The sloping distance between the working face and the coal mining face in the same direction shall not be less than 350m (Fig. 10c). The distance between the upper and lower coal seam working faces in the same mining (disc) area shall not be less than 500m (Fig. 11a), and the distance between the two wing working faces shall not be less than 500m (Fig. 11b).

(3) In the simultaneous excavation of double lanes, in order to avoid the mutual interference effects of the two parallel lanes in time and space, the front and rear offset between the double lanes should be greater than 150m (Fig. 12).

(4) The boundary on both sides of the working surface and above and above is the goaf, which is called the island working face. Affected by the superposition of pressure in multiple directions, the mining face has a higher stress level, the roof movement is severe, and the impact pressure is higher. The arrangement of the island working face (coal pillar) is shown in Figure 13.

(5) After the working face is recovered, the length of the goaf is approximately equal to the length of the working face (see Figure 14a), which is the “seeing” of the goaf. When the goaf is “see square”, the overburden rock is broken by positive “OX” (see Figure 14b). The stress concentration is high and the mine pressure is obvious. It is the key prevention and control stage of impact ground pressure.

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