SU735804A1 - Method of protecting preparatory mine working - Google Patents

Description

(54) METHOD FOR PROTECTING PREPARATORY

I

The invention relates to the mining industry and can be used in the underground mining of mineral deposits with the laying of the goaf.

There is a known method of protecting preparatory workings from rock pressure, which consists in erecting, on both sides of the protected, workings of rubble strips (backfill massif) of predetermined dimensions 1.

The disadvantage of this method is the large shrinkage of the production cross section, since the generation takes place in the zone of active displacement and subsidence of the subsurface rock formation.

A known method of guarding preparatory developments in deep mines on gently sloping seams consists in using the laying of the worked-out space by erecting the production of quarry strips with different compliance on both sides to form a discharge zone around the excavation 2.

The unloading around the mine is of a relative nature, since after the removal of purification works the load on double rubble strips increases dramatically, resulting in

That is why they are pressed and provoke swelling of weak soil rocks. Production dramatically reduces its cross-section or loses its stability altogether, as this affects the effect of the cleaning works. 5 The aim of the invention is to increase the sustainability of preparatory mine workings by creating a secondary local mining pressure zone. This is achieved by the fact that in the middle of the developed space of the lava in place

10 of the subsequent development or above the site of field development leaves an area of 25-30 m wide, which is not laid with a backfill material, and the development takes place after compaction of the collapsed rocks.

In FIG. 1 is a diagram of the location of preparatory workings and zones of primary and secondary local unloading (section across the rasters); in fig. 2 - layout for the subsequent passable

20 production (in the plane of the reservoir); in fig. 3 is a section A-A in FIG. 2; in fig. 4 is a diagram of the location of field-protected excavation (in the plane of the reservoir); in fig. 5 is a section BB in FIG. four.

The method is carried out as follows.

In the developed space, the discharge lava is laid down with waste rock 1 so that it is conducted in areas of the excavated space adjacent to the edges of the lava, and in its middle part 2, the roof is controlled by its complete collapse. The width of the unencumbered (middle) part 2 of the lava should be about {12 + 8- 12) 25- -30 m, where in is the width of the cross-section, section of preparatory production. The unlabeled part 2 of the excavated space forms the basis for the formation of the secondary zone of discharge of the 3 massif from the rock pressure, since its minimum width is caused by the localization of the inner zone. The length of the discharge lava is less than 120 m; the larger it is, the better from the point of view of the protection of the preparatory development.

The protection of the preparatory generation by the secondary unloading zone is that the impact of the development of the cleaning works adjacent to the discharge lava will affect only the external unloading zone 4. This effect does not extend to the internal zone 3. With preliminary creation of discharge zones, preparatory excavation 5 is located in the hull and compacted rocks (zone 3), and during the subsequent working-out period, the discharge lava is positioned so that the center of the unfilled part of the lava is above the field output 6 ..

Example 1. It is necessary to conduct preparatory generation 5 in the previously created discharge zone. To create this zone, a 200 m wide column is worked out. The width of the secondary (internal) discharge zone 3 is 25-30 m. Production is carried out in the center of the secondary discharge zone in the collapsed and compacted rocks, i.e. with a delay of no less than 0.6-1 lava length from the cleaning works.

Example 2 It is necessary to nabbotat field production 6, located in the soil of the reservoir at a distance of 10 m from it. For

of this center of the unencumbered pedigree part 2 of working lava is located above the mine. The length of the lava is 200 m, the widespread part of the developed space is 2.5-30 m.

The use of the proposed. of the way

Protection of preparatory workings ensures their stability both in the initial moment and in the development of cleaning works in the excavation field, which reduces the cost of maintaining preparatory workings.

Claims (2)

1. Nekrasovsky Ya. E. and others. Conducting drifts wide slaughter on flat seams. - M .: Nedra, 1969, p. 48-50. 2. Bazhin NP and others. Protection of preparatory workings without pillars. -M .: Nedra, 1975, p. 58-59 (prototype). 735804