CN114542109A - Reserved filling air return false tunnel structure and construction method thereof - Google Patents
Reserved filling air return false tunnel structure and construction method thereof Download PDFInfo
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- CN114542109A CN114542109A CN202210252711.2A CN202210252711A CN114542109A CN 114542109 A CN114542109 A CN 114542109A CN 202210252711 A CN202210252711 A CN 202210252711A CN 114542109 A CN114542109 A CN 114542109A
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- 238000010276 construction Methods 0.000 title claims abstract description 12
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 113
- 239000010959 steel Substances 0.000 claims abstract description 113
- 239000002184 metal Substances 0.000 claims abstract description 15
- 239000011083 cement mortar Substances 0.000 claims abstract description 4
- 239000004744 fabric Substances 0.000 claims abstract description 4
- 230000007246 mechanism Effects 0.000 claims description 10
- 239000002023 wood Substances 0.000 claims description 8
- 238000005553 drilling Methods 0.000 claims description 4
- 238000005065 mining Methods 0.000 abstract description 11
- 238000005336 cracking Methods 0.000 abstract description 3
- 238000004901 spalling Methods 0.000 abstract description 3
- 238000009434 installation Methods 0.000 abstract description 2
- 208000007101 Muscle Cramp Diseases 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 229910001294 Reinforcing steel Inorganic materials 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 238000009423 ventilation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 210000003462 vein Anatomy 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
- E21D11/14—Lining predominantly with metal
- E21D11/15—Plate linings; Laggings, i.e. linings designed for holding back formation material or for transmitting the load to main supporting members
- E21D11/155—Laggings made of strips, slats, slabs or sheet piles
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
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- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
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- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Devices Affording Protection Of Roads Or Walls For Sound Insulation (AREA)
Abstract
The invention discloses a reserved filling return air false tunnel structure and a construction method thereof, belongs to the field of mining, and solves the problem that a false tunnel is prone to bottom bulging, rib spalling and top plate cracking and collapsing. The invention is characterized in that a steel cylinder and a plurality of supporting shed frames are arranged in a false tunnel, the supporting shed frames are arranged along the length direction of the false tunnel, the steel cylinder is positioned on the supporting shed frames, round timbers are respectively arranged on two sides of the bottom of the steel cylinder, the round timbers are supported between the steel cylinder and the supporting shed frames, outer support rods are respectively arranged on two sides and the top of the steel cylinder, and the outer support rods are supported between the steel cylinder and the inner wall of the false tunnel. The construction method comprises the following steps: laying a metal net on the bottom plate of the false tunnel; arranging a supporting shed frame and installing a steel cylinder; the inside and the outside of the joint of the steel cylinder are both plastered by cement mortar, and plastic cloth and woven bags are wrapped outside the joint; two sides and the top of the steel cylinder are fixed by outer support rods, and the interior of the steel cylinder is fixed by an inner support rod through inner support; round logs are placed on two sides of the bottom of the steel cylinder and fixed; hanging a hanging rib, wherein the lower end of the hanging rib is connected with the metal net. The invention has simple structure, can realize modular installation and has simple construction.
Description
Technical Field
The invention belongs to the field of mining, and particularly relates to a reserved filling return air false tunnel structure in a downward cemented filling mining method and a construction method thereof.
Background
At present, due to complex mining conditions, research on mining methods with high ore body grade and poor stability of ore bodies and surrounding rocks is less, in order to improve ore recovery rate and reduce dilution rate in recent years, the downward drift cemented filling mining method is used as a safe and effective mining technology and is more and more widely applied.
When the downward horizontal cut-and-fill mining method is adopted for mining, in order to facilitate air return and filling operation, a series of roadways are excavated at certain heights along the inclination of ore bodies to serve as the middle section of a filling air return pair. The main engineering of the auxiliary middle section comprises a pulse-through return air duct, a return air shaft, a horizontal return air shaft connecting duct, a filling connecting duct, a pulse-along return air duct, a reserved filling return air duct in a pulse, a drilling chamber, a substation, a filling pulse-along duct and other engineering. An auxiliary middle section is generally responsible for the stoping operation of a middle section, and when the middle section mine volume served by the auxiliary middle section is mined, the auxiliary middle section is also filled completely. However, the air return duct of the auxiliary middle section still needs to be reserved, the air return duct is reserved in a reserved mode, and a reserved roadway channel is called a false tunnel. The false tunnel under the mine is arranged in the direction of the ore body and along the direction of the ore body in a multi-vertical mode and communicated with each other, and the false tunnel, the ventilation shaft and the filling shaft jointly form a filling air return channel of the mine.
The false tunnel is a key project reserved in the middle section of the mine auxiliary, the tunnel is seriously deformed and the temperature of a stope is increased along with the increase of the mining depth, and the false tunnel is used as an underground filling, air returning and safe escape passage, so that the stability and the reliability of the false tunnel are particularly important. During the production process, surrounding rocks at the position where the air return duct is filled are broken, joints are developed, and when the ground stress is increased, the false tunnel generates bottom bulging, rib spalling and top plate cracking and collapse, so that the normal production of mines is seriously influenced.
Disclosure of Invention
The invention aims to provide a reserved and filled return air false tunnel structure to solve the problem that a false tunnel is prone to bottom bulging, rib spalling and top plate cracking and collapsing.
The invention also aims to provide a construction method for reserving and filling the return air false tunnel.
The technical scheme of the invention is as follows: the utility model provides a reserve and fill false gallery structure of return air, is equipped with steel cylinder and a plurality of support rack in false gallery, and a plurality of support racks are arranged along false gallery length direction, and the steel cylinder is located the support rack, and steel cylinder bottom both sides are equipped with the log respectively, and the log supports between steel cylinder and support rack, and steel cylinder both sides and top are equipped with outer vaulting pole respectively, and outer vaulting pole supports between steel cylinder and false gallery inner wall.
As a further improvement of the invention, a plurality of groups of internal supporting mechanisms are arranged in the steel cylinder, the plurality of groups of internal supporting mechanisms are arranged along the axial direction of the steel cylinder, and the internal supporting mechanisms are supported on the inner wall of the steel cylinder.
As a further improvement of the invention, each group of internal stay mechanisms consists of two internal stay bars which are perpendicular to each other, and the internal stay bars are arranged along the radial direction of the steel cylinder.
As a further improvement of the invention, a plurality of supporting shed frames are connected into a whole through wood plates.
As a further improvement of the invention, a first cramp is arranged between the log and the support shed frame.
As a further improvement of the invention, the included angle between the upper plane and the side surface of the supporting shed frame is 90-95 degrees, and a second cramp is arranged between the upper plane and the side surface.
As a further improvement of the invention, a metal net is laid on the bottom plate of the false tunnel, a plurality of hanging ribs are arranged in the false tunnel, the upper ends of the hanging ribs are connected with the top plate of the false tunnel, and the lower ends of the hanging ribs are connected with the metal net.
As a further improvement of the invention, the steel cylinder is formed by connecting a plurality of steel cylinder units end to end.
As a further improvement of the invention, the steel cylinder unit is formed by mutually enclosing and connecting four arc steel plates.
A construction method for reserving and filling a return air false tunnel comprises the following steps:
A. leveling a bottom plate of the false tunnel, paving a metal net on the bottom plate, and drilling an anchor rod hole on a top plate of the false tunnel;
B. arranging a plurality of supporting shed frames along the length direction of the false tunnel;
C. placing a plurality of steel cylinder units on a support shed frame and connecting the steel cylinder units end to form steel cylinders;
D. the inside and the outside of the joint of the steel cylinder are both tightly plastered and smoothed by cement mortar, and plastic cloth and woven bags are wrapped outside the joint;
E. the two sides and the top of the steel cylinder are fixed by external support rods, so that the steel cylinder is prevented from deviating; the interior of the steel cylinder is fixed by an inner brace rod through an inner support, so that the steel cylinder is prevented from collapsing;
F. round timbers are placed on two sides of the bottom of the steel cylinder, the round timbers are fixed on the supporting shed frames by first cramping nails, and the supporting shed frames are connected into a whole by wood plates;
G. and hanging a hanging rib, wherein the upper end of the hanging rib is connected with the top plate of the false tunnel, and the lower end of the hanging rib is connected with the metal net.
The invention has the beneficial effects that: the method is characterized in that a steel cylinder is arranged in the false tunnel, after the middle section mine amount served by the auxiliary middle section is mined, the false tunnel is filled outside the steel cylinder, a hollow channel is formed inside the steel cylinder and is reserved as an air return channel, and the steel cylinder is not detached after filling and is directly used as a permanent support of the reserved roadway channel. The steel cylinder unit is enclosed by prefabricated circular arc steel sheet and closes to form, and the steel cylinder unit connects into the steel cylinder head and the tail again, simple to operate, and inside and outside all have fine support, and stability is good for the steel cylinder. The invention has simple structure, can realize modular installation, and has simple construction, small engineering quantity, small wind resistance coefficient, low cost and strong practicability.
Drawings
FIG. 1 is a schematic structural diagram of a reserved-filling air-return false tunnel structure according to the present invention;
FIG. 2 is a view A-A of FIG. 1;
FIG. 3 is a schematic structural view of a steel cylinder unit according to the present invention;
FIG. 4 is a schematic side view of the steel cylinder of the present invention.
In the figure: 1-arc steel plate; 2-end angle steel; 3-side angle steel; 4-connecting holes; 5-a steel cylinder; 51-a steel cylinder unit; 6-false tunnel; 7-reinforcing steel bars; 8-supporting the shed frame; 81-upper plane; 82-side; 9-log; 10-outer stay bar; 11-inner brace rod; 12-a metal mesh; 13-hanging the ribs; 14-wood board; 15-a first staple; 16-second staple.
Detailed Description
The present invention will be described in further detail with reference to the following drawings and examples.
Examples 1,
The utility model provides a reserve and fill false gallery structure of return air, be equipped with steel cylinder 5 and a plurality of support rack 8 in false gallery 6, a plurality of support rack 8 are arranged along 6 length direction in false gallery, steel cylinder 5 is located and supports rack 8, 5 bottom both sides of steel cylinder are equipped with log 9 respectively, log 9 supports between steel cylinder 5 and support rack 8, 5 both sides of steel cylinder and top are equipped with outer vaulting pole 10 respectively, outer vaulting pole 10 supports between steel cylinder 5 and the 6 inner walls in false gallery.
A plurality of groups of internal supporting mechanisms are arranged in the steel cylinder 5 and are arranged along the axial direction of the steel cylinder 5, and the internal supporting mechanisms are supported on the inner wall of the steel cylinder 5.
Each group of internal stay mechanisms consists of two internal stay bars 11 which are vertical to each other, and the internal stay bars 11 are arranged along the radial direction of the steel cylinder 5.
The plurality of supporting shelves 8 are connected into a whole through wood plates 14.
A first cramp 15 is arranged between the round log 9 and the supporting shed frame 8.
An included angle alpha between an upper plane 81 and a side surface 82 of the supporting shed frame 8 is 90-95 degrees, and a second cramp 16 is arranged between the upper plane 81 and the side surface 82.
A metal net 12 is laid on the bottom plate of the false tunnel 6, a plurality of hanging ribs 13 are arranged in the false tunnel 6, the upper ends of the hanging ribs 13 are connected with the top plate of the false tunnel 6, and the lower ends of the hanging ribs 13 are connected with the metal net 12.
The steel cylinder 5 is formed by connecting a plurality of steel cylinder units 51 end to end.
The steel cylinder unit 51 is formed by mutually enclosing and connecting four arc steel plates 1. And a reinforcing steel bar 7 is arranged between the two ends of the arc steel plate 1 to enhance the shaping of the arc steel plate 1.
A construction method for reserving and filling a return air false tunnel comprises the following steps:
A. leveling the bottom plate of the false tunnel 6, laying a metal net 12 on the bottom plate, and drilling an anchor rod hole on the top plate of the false tunnel 6;
B. a plurality of supporting shed frames 8 are arranged along the length direction of the false tunnel 6, and the supporting shed frames 8 are made of wood;
C. a plurality of steel cylinder units 51 are arranged on the support shed frame 8 and connected end to end into steel cylinders 5 through screw nuts;
D. the inside and the outside of the joint of the steel cylinder 5 are plastered tightly and flattened by cement mortar, and plastic cloth and woven bags are wrapped outside to prevent ash leakage;
E. the two sides and the top of the steel cylinder 5 are fixed by outer support rods 10 (made of square timber) to prevent the steel cylinder 5 from deviating; the interior of the steel cylinder 5 is fixed by an inner brace 11 (adopting square timber) to prevent the steel cylinder 5 from collapsing;
F. round timbers 9 are placed on two sides of the bottom of the steel cylinder 5, the round timbers 9 are fixed on the supporting shed frames 8 by first cramps 15, and the supporting shed frames 8 are connected into a whole by wood plates 14;
G. and hanging a hanging rib 13, wherein the upper end of the hanging rib 13 is connected with the top plate of the false tunnel 6, and the lower end of the hanging rib 13 is connected with the metal net 12.
The wall thickness of the arc steel plate 1 is 6mm, side angle steel 3 is welded on two side edges of the arc steel plate 1, connecting holes 4 are formed in the side angle steel 3, and the 4 arc steel plates 1 are connected with screw nuts through the connecting holes 4 in the side angle steel 3 to form a steel cylinder unit 51. The two ends of the arc steel plate 1 are welded with end part angle steels 2, connecting holes 4 are formed in the end part angle steels 2, the interval angles of the connecting holes 4 in the end part angle steels 2 are 30 degrees, and a plurality of steel cylinder units 51 are connected end to end and then connected into steel cylinders 5 through the connecting holes 4 in the end part angle steels 2 and screw nuts.
The construction of the false tunnel 6 is generally to ensure the filling and ventilation requirements of the subsequent mining of the mine, and can be built in or out of the vein.
During filling, the false tunnel 6 is filled outside the steel cylinder 5, and a hollow channel is formed inside the steel cylinder 5 and reserved as an air return channel. After filling, the steel cylinder 5 is directly used as a permanent support of a reserved roadway channel without being dismantled, the inner support rod 11 can be recycled after the false tunnel 6 is exposed, and the outer support rod 10 is not recycled.
Claims (10)
1. The utility model provides a reserve and fill pseudo gallery structure of return air which characterized in that: be equipped with steel cylinder (5) and a plurality of support rack (8) in false gallery (6), a plurality of support racks (8) are arranged along false gallery (6) length direction, steel cylinder (5) are located and are supported rack (8), steel cylinder (5) bottom both sides are equipped with log (9) respectively, log (9) support between steel cylinder (5) and support rack (8), steel cylinder (5) both sides and top are equipped with outer vaulting pole (10) respectively, outer vaulting pole (10) support between steel cylinder (5) and false gallery (6) inner wall.
2. A reserve air return pseudo-tunnel structure as claimed in claim 1, wherein: the steel cylinder (5) is internally provided with a plurality of groups of internal supporting mechanisms which are arranged along the axial direction of the steel cylinder (5), and the internal supporting mechanisms are supported on the inner wall of the steel cylinder (5).
3. A reserve air return pseudo-tunnel structure as claimed in claim 2, wherein: each group of internal stay mechanisms consists of two internal stay bars (11) which are vertical to each other, and the internal stay bars (11) are arranged along the radial direction of the steel cylinder (5).
4. A reserve air return pseudo-tunnel structure as claimed in claim 3, wherein: the plurality of supporting shed frames (8) are connected into a whole through wood plates (14).
5. The reserve-filled return air pseudo-tunnel structure according to claim 4, wherein: a first cramp (15) is arranged between the log (9) and the supporting shed frame (8).
6. The reserve-filled return air pseudo-tunnel structure according to claim 5, wherein: an included angle between the upper plane (81) and the side surface (82) of the supporting shed frame (8) is 90-95 degrees, and a second cramp (16) is arranged between the upper plane (81) and the side surface (82).
7. The reserve-filled return air pseudo-tunnel structure according to claim 6, wherein: a metal net (12) is laid on the bottom plate of the false tunnel (6), a plurality of hanging ribs (13) are arranged in the false tunnel (6), the upper ends of the hanging ribs (13) are connected with the top plate of the false tunnel (6), and the lower ends of the hanging ribs (13) are connected with the metal net (12).
8. A reserve-filled return air pseudo-tunnel structure according to any one of claims 1 to 7, wherein: the steel cylinder (5) is formed by connecting a plurality of steel cylinder units (51) end to end.
9. A reserve fill return air pseudo-tunnel structure as claimed in claim 8, wherein: the steel cylinder unit (51) is formed by mutually enclosing and connecting four arc steel plates (1).
10. A construction method for reserving and filling a return air false tunnel is characterized by comprising the following steps:
A. leveling a bottom plate of the false tunnel (6), paving a metal net (12) on the bottom plate, and drilling an anchor rod hole on a top plate of the false tunnel (6);
B. a plurality of supporting shed frames (8) are arranged along the length direction of the false tunnel (6);
C. a plurality of steel cylinder units (51) are arranged on a supporting shed frame (8) and connected end to form steel cylinders (5);
D. the inside and the outside of the joint of the steel cylinder (5) are plastered tightly and leveled by cement mortar, and plastic cloth and woven bags are wrapped outside;
E. the two sides and the top of the steel cylinder (5) are fixed by outer support rods (10) to prevent the steel cylinder (5) from deviating; the interior of the steel cylinder (5) is fixed by an inner brace (11) to prevent the steel cylinder (5) from collapsing;
F. round timbers (9) are placed on two sides of the bottom of the steel cylinder (5), the round timbers (9) are fixed on the supporting shed frames (8) through first cramping nails (15), and the supporting shed frames (8) are connected into a whole through wood plates (14);
G. and hanging a hanging rib (13), wherein the upper end of the hanging rib (13) is connected with the top plate of the false tunnel (6), and the lower end of the hanging rib (13) is connected with the metal net (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210252711.2A CN114542109A (en) | 2022-03-15 | 2022-03-15 | Reserved filling air return false tunnel structure and construction method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210252711.2A CN114542109A (en) | 2022-03-15 | 2022-03-15 | Reserved filling air return false tunnel structure and construction method thereof |
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| Publication Number | Publication Date |
|---|---|
| CN114542109A true CN114542109A (en) | 2022-05-27 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210252711.2A Pending CN114542109A (en) | 2022-03-15 | 2022-03-15 | Reserved filling air return false tunnel structure and construction method thereof |
Country Status (1)
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| CN (1) | CN114542109A (en) |
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2022
- 2022-03-15 CN CN202210252711.2A patent/CN114542109A/en active Pending
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