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Outburst prevention measures for coal roadway near coal lining

Source: xe1x.com Author: admin Date: 2019-11-04 15:56 heat:
Due to the construction of coal chute in the head room of 11081 machine lane, in order to ensure the safety of construction, anti-outburst measures shall be taken on the coal roadway near the gangway, as follows:

1. Project scope: All 8 meters west of the center line of the coal chute eye to the end of the nose chamber, all anti-outburst measures are taken.
2. Anti-outburst measures hole design 2 rows, drilling diameter φ75mm, interval between 700 300mm (in the shed), the first row is 1.3m away from the coal seam roof, the measure hole depth is 8.5m (in the direction of the tunnel projection), perpendicular to the coal Wall layout, construction along the roof of the coal seam. 6 dense fan-shaped holes are arranged at the end to release the pressure of the blank strip.
3. The effective inspection hole starts from 7m west of the center line of the coal bunker, and an effective inspection hole is arranged every 3m; the end of the coal wall is arranged 1m from the upper and lower sides, and the effective inspection hole diameter is 42mm, 700mm away from the coal seam roof. 7.5m deep (in the direction of the tunneling projection), arranged perpendicular to the coal wall, and constructed along the roof of the coal seam.
4. The efficiency inspection index adopts drill cuttings gas desorption method. The critical value is 200Pa. When the desorption index is less than 200Pa, the prominent danger of coal and gas is eliminated, and the coal bunker is allowed to be constructed. When the desorption index is greater than or equal to 200Pa, the coal and gas are still in prominent danger. In addition, supplementary measures must be taken (a row of measure holes must be added between two rows of measure holes within 3m to the left and right of the index overrun limit).
5. In the process of construction, such as pinch drilling, spray holes, etc., should be added between the holes around the measure holes to discharge holes in order to fully relieve the pressure of the coal body.
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