A gob-side digging method for piers without blasting and top cutting

Abstract

The invention discloses a gob-side excavation method for pier columns without blasting, the method comprising the steps of: arranging a plurality of slit holes, the plurality of slit holes together form a pre-splitting slit, and drilling the slit holes ahead of the working surface by 60 ~100m; Excavate the coal pillar side at intervals of 5-10m to arrange concrete pier molds on the side of the coal pillar in the trough near the next working face; use single hydraulic props and Π-shaped steel as temporary supports in the trough Anchor construction in the trough close to the next working face; recovery of single hydraulic props at 2‑5m behind the working face; along the roof of the gob-side excavation roadway, the pre-split kerf collapses along the kerf hole, Eliminate the suspended roof, fill the goaf, and carry out roadway construction along the gob after the adjacent goaf is mined at intervals of 3-5m coal pillars. The invention adopts pier pillars without blasting to cut the top and relieve pressure, and the adjacent working face can carry out small coal pillar gob-side digging operations, which greatly relieves the tense situation of mine excavation and replacement, reduces the cost of reverse repair of gob-side digging roadways, and improves the coal recovery rate .

Description

technical field

[0001] The invention relates to a gob-side digging method for pier pillars without blasting and top-cutting, and belongs to the technical field of shallow geothermal energy. Background technique

[0002] The traditional gob-side entry generally starts construction more than 10 months after the mining of the adjacent working face. The coal pillars are small, and the roadway of gob-side entry is in the stable zone of rear bearing pressure, so the maintenance of the roadway is relatively easy. Mining of coal seam groups at close distances has high in-situ stress, great influence of mining, and tight excavation succession. Often the adjacent working faces are excavated before the goaf is completely mined, and the sideways hanging area of ​​the goaf next to the coal pillar is prone to appear. large and insufficient caving, the roadway is significantly affected by the movement of the overlying rock in the adjacent goaf, and the mine pressure is severe. Under the in...

Examples

Embodiment 1

[0020] Embodiment 1: as Figure 1-4 Shown, a kind of pier pillar non-blasting top cutting method for gob-side entry, the method includes the following steps:

[0021] 1. Construction slit hole 2

[0022] The location of the top-cutting and slotting hole beside the roadway should be selected on the 4th side of the coal pillar along the channel, and the drilling hole is about 0.5~0.8m away from the side of the small coal pillar. The radial direction of the slit hole 2 forms an angle α with the top plate, such as Figure 4 As shown, the depth H is determined according to the broken expansion coefficient of the roof strata; in order to make the goaf roof collapse smoothly after cutting and reduce the friction effect on the roadway roof during the collapse process, the roof cutting angle α needs to be determined according to the roof cutting layer , the reasonable cutting depth is 3~5 times of the mining height of the working face;

[0023] 2. Arrangement of piers 3

[0024] Ex...

technical field

[0001] The invention relates to a gob-side digging method for pier pillars without blasting and top-cutting, and belongs to the technical field of shallow geothermal energy. Background technique

[0002] The traditional gob-side entry generally starts construction more than 10 months after the mining of the adjacent working face. The coal pillars are small, and the roadway of gob-side entry is in the stable zone of rear bearing pressure, so the maintenance of the roadway is relatively easy. Mining of coal seam groups at close distances has high in-situ stress, great influence of mining, and tight excavation succession. Often the adjacent working faces are excavated before the goaf is completely mined, and the sideways hanging area of ​​the goaf next to the coal pillar is prone to appear. large and insufficient caving, the roadway is significantly affected by the movement of the overlying rock in the adjacent goaf, and the mine pressure is severe. Under the in...

Examples

Embodiment 1

[0020] Embodiment 1: as Figure 1-4 Shown, a kind of pier pillar non-blasting top cutting method for gob-side entry, the method includes the following steps:

[0021] 1. Construction slit hole 2

[0022] The location of the top-cutting and slotting hole beside the roadway should be selected on the 4th side of the coal pillar along the channel, and the drilling hole is about 0.5~0.8m away from the side of the small coal pillar. The radial direction of the slit hole 2 forms an angle α with the top plate, such as Figure 4 As shown, the depth H is determined according to the broken expansion coefficient of the roof strata; in order to make the goaf roof collapse smoothly after cutting and reduce the friction effect on the roadway roof during the collapse process, the roof cutting angle α needs to be determined according to the roof cutting layer , the reasonable cutting depth is 3~5 times of the mining height of the working face;

[0023] 2. Arrangement of piers 3

[0024] Ex...

Images