RU2726823C1 - Temporary protective rock web - Google Patents

Abstract

FIELD: protection methods.

SUBSTANCE: invention relates to a method of protection and is intended for attenuation of shock air waves (SAW) of large and super-rated power in mine openings in order to preserve underground structures and communications. TPBL (1) consists of rock-cut rock lying in passage (2) with cuts (3) and completely closing it. TPBL (1) is formed by preliminary driving of fans of paired risers (4), by filling borehole charges therein. In rock before TPBL (1) there are two adjacent side dead-end tunnel (5) at acute angle to direction of SAW (7) and transverse area equal to area of section of main passage (2), length 5…15 sizes of passage width (2). Two adjacent side dead-end tunnels (5) are additionally made "downward" - inclined downward from main passage (2) at acute angle 15…50° to SAW (7) direction.

EFFECT: reduction of power and time costs for release of passage of mine working from collapsed temporary protective bridging lintel (TPBL), and namely to facilitate filling of broken rock from pass of mine working to dead-end tunnels.

1 cl, 4 dwg

Description

The invention relates to protection methods and is intended to attenuate air blast waves (AEC) in mine workings in order to preserve underground structures and communications, and preferably to protect the protected (main) volume from possible emergencies (during the explosion and propagation of high-power air-blast). It can be used in blasting operations with over-rated air-blast parameters, as well as to protect the passage to the main protected volume from high and over-rated air-blast power when the latter propagates along a connecting mine.

Known "Heat-extinguishing device for extinguishing air-blast of repeated action" according to the patent of the Russian Federation: RU 2249113 C1 dated 03/27/2005, IPC E21F 17/103, E21F 5/00 - [1], consisting of a mine channel with sections of wells made in it, while each well of the section is equipped with a conoidal hole at the entrance to the rock, and at the end of the well - chambers of destroyed rock, remote from each other and from the longitudinal axis of the channel, characterized in that each section of the channel wells is made with a sawtooth surface, the protrusions of which are directed against the intended directions of air blast waves (air blast), in the depressions of the ledges there are conoidal holes, from which the wells are located at an angle of ± (10 ... 70 °) to the assumed air blast direction. In this device, the air-blast is extinguished due to its flow into the conoidal expansions in the surface of the passage at the entrance to the rock and further along the wells into the chambers of the destroyed rock. The invention has a low efficiency of air-blast extinguishing, especially in the longitudinal direction.

It is known "Device for protection against air blast in mine passages" according to patent RU 2167304 C1 dated 20.05.2001, IPC E21F 5/00 - [2], containing hollow elements fixed on the mine passage with a step equal to 2 ... 4 of the mine diameter barrel, made in the form of thin-walled shells with sealed evacuated cavities, with some of the thin-walled shells made in the form of columns. In this device, the air-blast is extinguished due to crushing of thin-walled shells (consumption of air-blast crushing energy), and due to expansion of the air-blast in the crumpled cavities of thin-walled shells. The device has a low efficiency of air-blast extinguishing, especially in the longitudinal direction. In addition, air-blast extinguishing occurs with a significant amount and distribution of thin-walled shells along the mine passage. Also, the implementation of the device requires high costs of high-quality metal (to maintain vacuum) for thin-walled shells, which increases the cost of its use.

Known temporary protective rock bulkhead (book: Gurin A.A., Maly P.S., Savenko S.K. Air shock waves in mine workings. 2nd edition, revised and added. M., Nedra, 1983, p. 163, Fig. 8.14.) - [3], containing pre-collapsed rock in the passage, completely covering its volume, and in front of the bulkhead has a rising compensation chamber inclined at an acute angle in the direction of air-blast - a dead-end tunnel.

The disadvantage of the known temporary protective rock bulkhead [3] is:

- the complexity of the construction and construction technology of the inclined compensation chamber;

- insufficient efficiency of air-blast extinguishing in one upward working (mountain pass);

Known temporary protective rock bulkhead (book: Gurin A.A., Maly P.S., Savenko S.K. Air shock waves in mine workings. 2nd edition, revised and added. M., Nedra, 1983, p. 162, Fig. 8.13.) - [4], containing collapsed rock, located in the passage with cuts and completely covering it, which is formed by preliminary driving of fans of paired rising ones, placing borehole charges in them and detonating the latter in order from the ends of the fan paired uprising towards its center.

The disadvantage of the analogue [4] is that when exposed to over-rated air-blast values, it (the bulkhead) may not withstand such a load and allow the over-design air-blast to break through into the protected volume. In addition, after the redemption of air-blast or air-blast series, significant material and time costs are required to eliminate the protective temporary bulkhead and ensure the need for passage into the main protected volume.

The known "Method of protection against an air shock wave with a temporary rock bridge" according to the RF patent: RU 2236598 C1 dated 20.09.2004, IPC E21F 5/00, E21F 17/103 - [5], as well as a device for its implementation, disclosed in graphic materials analogue. The device of a protective temporary rock bulkhead according to the method [5] consists of located in the mine workings (tunnel) in front of the protected volume of the fans of the paired rising with the blast-hole charges of the explosive embedded in them. After the fans of the paired ones rising towards the protected volume, the mine working contains a ledge reinforced with anchors located on the roof of the mine working (tunnel). In front of the fans of the paired uprising (the first "fan of the paired uprising") in the direction opposite to the protected volume, in the bottom of the mine working (tunnel) there is a pit closed by a slab with an explosive charge located under it along its perimeter, the volume is equal to or greater than the calculated volume the collapsed rock of the temporary bulkhead. A sensor is located at the entrance to the protected mine working (tunnel) in front of the protected volume and the location of the fans of the paired rising ones at a sufficient (calculated) distance to trigger the blast-hole charges and form a temporary rock bulkhead. A ledge reinforced with anchors is located at the weakest point of the rock bulkhead. The ledge reinforced with anchors is arranged in the weakest point of the rock bulkhead (after the rock burst), namely from above it strengthens the rock bulkhead and will not allow air-blast breakthrough into the protected volume. A pit closed by a slab can be arranged directly under the fans of the paired rising ones, while the slab is selected for the load of both the impact from the masses of the caving rock, and the load from the utilization of the energy of the oversized air-blast on the temporary rock bulkhead. The sensor responds only to the passage of the destructive air-blast oversized parameters. From the sensor, the signal is sent to the automatic control system for blasting blast-hole explosive charges, and when a low-power air-blast passes through, the volume is protected by known methods, for example, using doors, gates, removable temporary jumpers, etc. The sensor is located at a certain (calculated) distance from the protected volume and fan-shaped paired uplifts, which will allow, when the air-blast passes from the sensor to the rock bulkhead under construction, to detonate in advance (in the above sequence) the blast-hole charges and collapse the rock, thereby completely blocking the mine workings (tunnel ) leading to the volume to be protected. The sensor can be located, for example, on a temporary partition (doors), etc.

The disadvantage of the protective temporary rock bulkhead device according to the method [5] is also that when exposed to oversized air-blast values, it (the bulkhead) may not withstand such a load and allow the over-design air-blast to break through into the protected volume. In addition, when exposed to oversized air-blast values, there is a likelihood of triggering an explosive embedded under the slab covering the pit, which reduces the reliability of the technical solution as a whole.

The prototype of the claimed invention is "Temporary protective rock bulkhead" according to the RF patent: RU 2249114 C1 dated 03/27/2005, IPC E21F 17/103, E21F 5/00 - [6], containing collapsed rock located in the passage with cuttings and completely the closing one, which is formed by preliminary driving of the fans of the paired rising ones, the laying of borehole charges in them. In the rock in front of the temporary rock bulkhead, two conjugated lateral horizontal dead-end tunnels are made at acute angles of ± 40 ... 60 ° to the direction of the air blast wave (air blast) with a transverse area equal to the cross-sectional area of the main passage and 5 ... 5 dimensions of the passage width. From the side of the air-blast entrance, the corners of the mating surfaces of the protected passage and the dead-end tunnels are made rounded.

The disadvantage of the prototype [6] is that the elimination of such a protective rock bulkhead requires significant energy and time costs for the transportation of fractions of collapsed rock from the mine workings into horizontal dead-end tunnels.

The above drawback sets the task of minimizing the energy and time costs for freeing the mine passage from the temporary protective rock bulkhead (VZP), namely, to reduce the energy and time costs for transporting the collapsed rock from the mine working to the horizontal dead-end tunnels.

The specified task (essence of the invention) is achieved by the fact that the VZP, containing the collapsed rock, located in the passage with cuts and completely covering it, which is formed by preliminary driving of the fans of the paired rising ones, the laying of blast-hole charges in them, while in the rock in front of the VZP two of conjugated lateral dead-end tunnels at an acute angle to the air-blast direction, a transverse area equal to the cross-sectional area of the main passage and a length of 5 ... 15 dimensions of the passage width, while two conjugated lateral dead-end tunnels are additionally made inclined downward from the main passage at an angle of 15 ... 50 ° to the direction Air-blast. The angle of inclination is "minus" 15 ... 50 ° to the air-blast direction mainly depends on the calculated value of the crushed rock fractions, as well as on other design parameters.

The technical result is to reduce the energy and time costs for freeing the mine passage from the collapsed temporary protective rock bulkhead, namely, to facilitate the filling of the collapsed rock from the mine passage into the dead-end tunnels.

The technical result is achieved by the fact that when filling in additionally inclined downward ("descending") two dead-end tunnels located from the main passage at an angle of 15 ... 50 ° (downward) to the direction of air-blast, the rock from the passage of the mine working, the rock under the influence of gravity will crumble on their own and fill these two dead-end tunnels. At the same time, the claimed technical solution, as well as in the prototype, retains a high extinguishing efficiency in two dead-end tunnels of air-blast, including over-rated values, which is guaranteed to prevent the over-design air-blast from breaking into the protected volume.

In the claimed technical solution, as well as in the prototype, the formed VZPP is used from the rock, collapsed into the passage with cuts and completely closes it. The VZPP is formed by preliminary driving of the fans of the paired rising ones, placing the borehole charges in them and detonating the latter (from the sensor signal taken out in the direction of the arrival of the over-rated air-blast) in sequence from the ends of the fan of the coupled rising ones to its center. The oversized air-blast is additionally weakened in two conjugated lateral dead-end tunnels located in a horizontal projection (top view) at acute angles of ± 40 ... 60 ° to the air-blast direction (the conjugation angle depends on the type of rock). Two lateral dead-end tunnels are made with a transverse area equal to the cross-sectional area of the main passage and a length of 5 ... 15 dimensions of the passage width, while on the side of the air-blast approach, the corners of the passage mating surfaces (into the protected volume of the mine) and the dead-end tunnels are rounded. In contrast to the prototype, two adjoining lateral dead-end tunnels are additionally made inclined downward from the main passage at an angle of 15 ... 50 ° (for example, 45 °) to the direction of the air-blast. This allows you to significantly reduce the energy and time costs for clearing the mine passage from the collapsed runway. Since the collapsed rock from the mine passage in will be filled in part using the Earth's gravity, under the action of which the fractions of the collapsed rock of the VZPP will roll (crumble) to the lower ends of the two dead-end tunnels.

Two conjugated lateral descending dead-end tunnels will significantly reduce the load from the air-blast on the runway and, thus, will guaranteed not to allow the over-rated air-blast to break through into the protected volume. Dead-end tunnels are technologically advanced to manufacture, and after extinguishing the air-blast, they are used to accommodate rock fractions from the VZPP in them. The location of two conjugate lateral horizontal dead-end tunnels, at acute angles of ± 40 ... 60 ° to the air-blast direction, leads to a significant removal of air-blast energy from the air-blast zone. The fillet angle (eg 50 °) depends on the type of rock. Implementation of conjugate horizontal dead-end tunnels with a transverse area equal to the cross-sectional area of the main passage will allow, without air-blast wave surges (compaction - rarefaction, which can have a harmful additional effect on a temporary protective rock bulkhead), redirect air-blast energy into the dead-end tunnels. Implementation of conjugated horizontal dead-end tunnels 5 ... 15 (for example, 12) long and equal in volume to or greater than the calculated volume of the caving rock of the temporary bulkhead, will optimally and efficiently extinguish the air-blast energy. In this case, it is necessary to proceed (find the optimal solution for the length of the tunnels) from the interface angle, the type of soil and the cost of tunneling these tunnels. After extinguishing the air-blast energy (or a series of air-blast impacts) at the air-blast zone and in the dead-end tunnels, the rock of the air-blast zone can be removed with minimal energy and time costs into the free volumes of the descending dead-end tunnels used for air-blast blanking, located in the immediate vicinity of the site of the air-blast construction, namely in front of her. That is, quickly ensure the passage through the protected volume.

In FIG. 1 shows a longitudinal section of V-V VZPP after its formation by an explosion in the passage of a mine, and in the place where the fans of the paired raising fans are driven, as well as in the place where two conjugated lateral descending dead-end tunnels are arranged at acute angles to the direction of the air-blast.

In FIG. 2 - longitudinal section В-В after the restoration of the passability of the mine passage with the removal of VZPP fractions into the descending dead-end tunnels.

In FIG. 3 is a top view of a longitudinal section D-D of a mine working after extinguishing the air-blast energy and removing rock fractions into descending dead-end tunnels, that is, after restoring the passability of the passage.

In FIG. 4 is a schematic view of the preliminary preparation for the construction of a VZPP in a mine working, namely:

- in Fig. 4 a) - cross section А-А of a mine working (protected passage with cuts) at the place of driving of the fans of the paired rising;

- in Fig. 4 b) - longitudinal section В-В of the mine workings (protected passage and descending dead-end tunnels);

- in Fig. 4 c) is a bottom-up view of a longitudinal section BB of a mine working;

- in Fig. 4 d) - cross section Г-Г of a mine with descending dead-end tunnels.

VZPP 1 contains collapsed rock, located in passage 2 with cuts 3 and completely covering it, which is formed by preliminary driving of fans of paired rising 4 (4.1, 4.2, 4.3, 4.4, 4.5 and 4.6), placing borehole charges in them and blasting the latter in sequence from the ends of the fan of paired uprising to its center. In the rock in front of the temporary rock bulkhead 1, two conjugated lateral descending dead-end tunnels 5 are made in a horizontal projection at acute angles of ± 40 ~ 60 ° to the direction of air-blast 7 with a transverse area equal to the cross-sectional area of the main passage, and a length of 5 ~ 15 dimensions of the passage width. In this case, two coupled lateral dead-end tunnels 5 are made inclined downward (descending) from the main passage at an angle of 15 ... 50 ° (for example, 45 °) to the direction of the air-blast. From the side of the air-blast 7 approach, the corners of the mating surfaces of the protected passage 2 and the descending dead-end tunnels 5 are made rounded. After protection from the destructive action of air-blast and ensuring the passability of the passage 2, the rock 6 of the bulkhead 1 is stored by pouring it into the descending dead-end tunnels 5.

The claimed technical solution works - the device is as follows:

Initially and in advance, in passage 2, in front of the protected rock bulkhead, fan paired rising 4 (4.1, 4.2, 4.3, 4.4, 4.5 and 4.6) are erected and blasthole charges are placed in them. Then, from the side of the planned approach of the air-blast 7, to the place of formation of the bulkhead, two conjugate lateral descending ones are performed, inclined downward at an angle of 15 ... 50 ° (for example, 45 °) to the direction of the air-blast 7, dead-end tunnels 5 at acute angles ± 40 ... 60 ° , also to the direction of approach of the air-blast 7 with a transverse area equal to the cross-sectional area of the main passage, and a length of 5 ... 15 dimensions of its width. If necessary, the construction of temporary rock bridges is undermined by blast-hole charges located in fan-shaped rising 4 in sequence from the ends of the fan of paired rising to its center. When blast-hole charges are detonated in fan paired rising 4, the rock collapses and completely blocks the passage 2, while the VZPP 1 is ready to extinguish the air-blast 7 of the calculated and over-rated power. When approaching, air-blast 7 is partially extinguished at the temporary rock bulkhead 1, and partially separated and supplied for further extinguishing into two descending dead-end tunnels 5 (to reduce the load on the runway 1). In two descending dead-end tunnels 5, the air-blast 7 is extinguished both due to the absorption of the wave by the walls of the tunnel 5, and due to periodic reflection (re-reflection).

After the end of the action of air-blast 7 at VZPP 1 and on two descending dead-end tunnels 5, (after elimination of possible destruction), the rock fractions 6 of the VZPP 1 are removed into the free volumes of two descending dead-end tunnels 5 and, thus, ensure the passability of the passage 2 of the mine working into the main protected volume. The cleaning of the rock of the temporary dam 1 is performed in a mechanized way.

The technical and economic advantage of the invention lies in the fact that the high efficiency of protection of the protected (protected) volume by the structure (by means of an explosion) of the VZPP 1, significantly reduced the energy and time costs of the subsequent restoration of the full passability of the mine passage during the pouring and storage of rock fractions 6 VZPP 1 in descending dead-end tunnels 5.

It is assumed that the proposed VZP 1 is designed to protect against air-blast 7 of high and extra high power of single action. At the same time, the parameters and characteristics of the declared VZPP 1 are not inferior to the protective properties of permanent bridges, for example, from concrete, but at the same time, the subsequent full passability of the mine passage 2 is ensured.

The creation of a VZP in conjunction with the limiting and distinctive features of the claims is new for generally known air-blast protection devices and, therefore, meets the "novelty" criterion.

The set of features of the claims is not known at this level of technical development and does not follow from well-known devices for protection against air-blast, which proves compliance with the criterion of "inventive step" (this is also evidenced by the conducted patent search and reference to information sources [1] - [6]) ...

The implementation of the proposed temporary protective rock bridge can be carried out by known and applied methods, technologies and equipment, from which follows the compliance with the criterion of "industrial applicability".

Sources of information:

1. RF patent: RU 2249113 C1 dated March 27, 2005, IPC E21F 17/103, E21F 5/00, "Reusable heat extinguishing device".

2. RF patent: RU 2167304 C1 from 20.05.2001, IPC E21F 5/00, "Device for protection against a shock wave in mine shafts."

3. Book: Gurin A.A., Maly PS, Savenko S.K. Air shockwaves in mine workings. Ed. 2nd, rev. and add. M., Nedra, 1983, p. 163, fig. 8.14.

4. Book: Gurin A.A., Maly PS, Savenko S.K. Air shockwaves in mine workings. Ed. 2nd, rev. and add. M., Nedra, 1983, p. 162, fig. 8.13.

5. RF patent: RU 2236598 C1 from 20.09.2004, IPC E21F 5/00, E21F 17/103, "Method of protection against an air shock wave by a temporary rock bridge".

6. RF patent: RU 2249114 C1 dated 27.03.2005, IPC E21F 17/103, E21F 5/00, "Temporary protective rock bridge" - prototype.

Claims (1)

Temporary protective rock bulkhead, containing collapsed rock, located in the passage with cuts and completely covering it, which is formed by preliminary driving of paired rising fans, placing borehole charges in them, while in the rock in front of the temporary protective rock bulkhead two conjugated lateral blind tunnels are made at an acute angle to the direction of air-blast with a transverse area equal to the cross-sectional area of the main passage, and a length of 5 ... 15 dimensions of the passage width, characterized in that two adjacent lateral dead-end tunnels are additionally made "descending", inclined downward from the main passage at an angle of 15 ... 50 ° towards the air-blast direction.

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