First, the determination of the closed position:
The specific location is determined according to the actual situation on site.
Second, the closed construction requirements:
1. Sealing must be done with non-combustible materials. (red brick or stone)
2. The closed position must be selected in the roadway with small dynamic pressure, stable surrounding rock and regular roadway. The closed outer side should have a distance of 4-5 meters.
3. The sealing structure requires stable and strict wall structure. Permanently sealed with a minimum of 370mm wall. The firewall is closed with two 370mm wall walls, filled with 20m thick loess. The wall base and the wall of the wall must be tightly combined and integrated into one. The coal roadway must be closed, the depth of the sump is 0.5m after seeing the coal, the depth of the top groove is 0.3m after seeing the coal, the depth of the ground is 0.2m after the real coal, and the width of the gutter is greater than 0.3m. The gutters are not required to be sealed along the roadway, but the loose rock mass must be removed, see the hard rock mass.
4. During the masonry, the gap must be staggered, no heavy seams may occur, the mortar is required to be full, and the double stone wall is used for masonry. The wall is filled with loess or mixed soil and compacted.
5. After the wall is built, the wall surface must be treated with a surface. The thickness is required to be greater than 20mm, the wall surface is flat, the convex and concave in 1m is not more than 10mm, and the skirt around the wall is required to be no less than 0.1m. It is necessary to listen to no sound, to see no light, and to touch without feeling.
7. After the wall is built, set the construction instructions board and register the number.
8. It is forbidden to pile up sundries and other equipment and materials within 5 meters around the confined facilities.
Third, preparation before construction
1. Before the construction, prepare the masonry materials, stack them on both sides of the roadway at the construction site, and clean up the debris near the construction site and the retreat route to ensure the smooth route of the retreat.
2, pre-construction, ready to complete iron shovel, picks, sledgehammer, Qianzai, spatula, rope and other tools as well as the observation tube, pipe and other material measures.
3. Before construction, it is necessary to gradually check the top and the gang near the construction site from the outside to the inside, and find the problem in time for proper construction. Within 5 meters before sealing, it is necessary to ensure reliable support, no filming and roofing.
4. Before construction, all construction personnel must be organized to learn construction measures.
Fourth, construction safety technical measures
1. Before construction, the concentration of harmful gas such as gas and carbon dioxide at the construction site must be checked. The construction site must be well ventilated, and the concentration of harmful gases such as gas and carbon dioxide should not exceed the safety regulations of coal mines.
2, closed construction must be grooved, with a sledgehammer, brazing or pneumatic picking operation, first smash two troughs, then smash the bottom trough, and finally the top trough, the depth of the trough should not be less than 300mm, it is strictly prohibited to use the blasting method to cut the trough.
3. When constructing a double-layer stone wall, the thickness of the wall is not less than 2 meters, and the ratio of sand to sand of the mortar is 1:3.
4. During construction, it is necessary to remove the impetuous rafts at the top and at the same time, so as to prevent the loose meteorites from remaining around the airtightness and affecting the tightness of the airtightness.
5. When laying bricks, all the mortars should be filled with mortar to make the wall surface smooth, the vertical joints should be staggered, the horizontal joints should be horizontal, and the arrangement must be neat, to prevent cracks, heavy seams and empty seams.
6. When the closed wall is capped, it must be built from the sides to the middle. If there are floating rafts and live stones, it must be cleaned and then slabed to ensure tight closure.
V. Other safety precautions
1. During construction, it must be ensured that the construction location meets the construction design requirements.
2. Before construction, the rails, steel pipes and cables inside and outside the wall must be removed.
3. When transporting confined materials, the distance between the carts must be greater than 15 meters. When transporting the materials, the personnel must pay attention to safety. Only one piece is allowed to be held at a time to prevent accidents such as bumping hands and feet.
4. When the material stone masonry is sealed, the personnel who deliver the stone must wait for the construction personnel to hold the material stone before releasing the hand, so as to prevent the stone from falling and injuring people.
5. During construction, the shift squad leader must closely monitor the safety conditions such as roof and ventilation at the site. If special circumstances are encountered, it must report to the follow-up leader and dispatching room in time, and take measures to continue the operation.
6. Report the situation to the dispatching room before and after construction.
7. After the closed construction is completed, the technical person in charge shall check and accept the construction quality and site safety.
8. Strictly in accordance with the provisions of the “Safety Regulations for Coal Mines†that are not covered in this measure.
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