CN112112672A - Gob-side entry retaining roadside support body construction method based on gangue cement-based material - Google Patents

Gob-side entry retaining roadside support body construction method based on gangue cement-based material Download PDF

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Publication number
CN112112672A
CN112112672A CN202011002305.8A CN202011002305A CN112112672A CN 112112672 A CN112112672 A CN 112112672A CN 202011002305 A CN202011002305 A CN 202011002305A CN 112112672 A CN112112672 A CN 112112672A
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CN
China
Prior art keywords
filling
entry retaining
gob
support
cement
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202011002305.8A
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Chinese (zh)
Inventor
巨峰
张雅珍
肖猛
何泽全
周成
王栋
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China University of Mining and Technology CUMT
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China University of Mining and Technology CUMT
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Filing date
Publication date
Application filed by China University of Mining and Technology CUMT filed Critical China University of Mining and Technology CUMT
Priority to CN202011002305.8A priority Critical patent/CN112112672A/en
Publication of CN112112672A publication Critical patent/CN112112672A/en
Pending legal-status Critical Current

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Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D23/00Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
    • E21D23/04Structural features of the supporting construction, e.g. linking members between adjacent frames or sets of props; Means for counteracting lateral sliding on inclined floor
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21FSAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
    • E21F13/00Transport specially adapted to underground conditions
    • E21F13/06Transport of mined material at or adjacent to the working face
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21FSAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
    • E21F15/00Methods or devices for placing filling-up materials in underground workings
    • E21F15/005Methods or devices for placing filling-up materials in underground workings characterised by the kind or composition of the backfilling material
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21FSAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
    • E21F15/00Methods or devices for placing filling-up materials in underground workings
    • E21F15/02Supporting means, e.g. shuttering, for filling-up materials
    • E21F15/04Stowing mats; Goaf wire netting; Partition walls

Abstract

The invention discloses a construction method of a gob-side entry retaining roadside support body based on a gangue cement-based material, and relates to the technical field of underground gob-side entry retaining roadside support. Firstly, arranging a single support column in a gangue transport roadway, and arranging a baffle beside the single support column; then, starting filling equipment, and sequentially filling the waste rocks in the goaf from far to near; then, when the filling body is close to the gob at the entry retaining position, filling and tamping the cementing body; and finally, after the filled wall is fully solidified and stabilized, recovering a row of partial or all single pillars and hinged top beams in the middle of the entry retaining. The invention is suitable for a solid filling working surface, gob-side entry retaining is carried out by adopting a method of combining a single prop baffle and a rammed cement body for entry retaining, a single prop support hinged with a top beam or a steel beam can play a role of temporary support, and the stability of the lane is maintained; after the cementing material is tamped, the effect of increasing the supporting strength can be rapidly achieved, the time for waiting for final setting in cemented filling is shortened, the initial bearing capacity is strong, and the roadway retaining effect is good.

Description

Gob-side entry retaining roadside support body construction method based on gangue cement-based material
Technical Field
The invention relates to the technical field of underground gob-side entry retaining roadside support, in particular to a construction method of a gob-side entry retaining roadside support based on a gangue cement-based material.
Background
The gob-side entry retaining is that one lane is retained by adopting a reasonable in-lane supporting technology and a roadside supporting technology and is normally used as the next working face, and the gob-side entry retaining has the advantages of improving the resource recovery rate, relieving the shortage of excavation and replacement, providing space for gas control and the like.
However, large deformations of the roadway are usually produced as the gob-side entry needs to withstand multiple mining effects, in particular roof breakage, rotation and subsidence. Therefore, how to support the top plate by using the waste rock in the gob, and reduce the sinking and breakage of the top plate, thereby reducing the deformation of the roadway and effectively supporting the top plate in the roadway and the closed gob is always the problem to be solved by engineering technicians in the field.
In order to solve the problems, the invention patent of China with the publication number of 103850708A discloses a gob-side entry retaining method adopting a concrete filling body, so as to improve the support strength of an retained roadway. However, the method firstly needs a concrete preparation and conveying system, and secondly needs to erect the single prop in the goaf, so that the process is complex, and the single prop erected in the goaf is not in line with safety regulations and is difficult to recover.
The invention discloses a Chinese patent with publication number 107387083A, which discloses a method for constructing a roadside support body of a gob-side entry retaining of a medium-thickness coal seam supported by waste rock, and the method can reduce the sinking amount of a top plate, improve the supporting force of the waste rock on the top plate at the goaf side and improve the maintenance effect of a roadway; the filling material consumption is saved, and the entry retaining cost and the labor intensity of workers are reduced. However, the method adopts paste filling or high water filling to arrange a layer of filling belt, has complex process and cannot be used on a solid filling working surface; moreover, the paste and the high water filling and condensation both need time, the supporting force is difficult to form in the early period, and the control effect on the top plate is poor.
Therefore, in view of the above problems, there is a need to provide a method for constructing a roadside support body with simple process, strong initial bearing capacity and good roadway retaining effect, so as to meet the requirements of coal mine safety production.
Disclosure of Invention
The invention provides a method for constructing a gob-side entry retaining roadside support based on a gangue cement-based material, which comprises the following steps:
the method comprises the following steps: two rows of mechanical constant-resistance single pillars are arranged in the entry retaining along the advancing direction of the working face, and a hinged top beam is arranged above the two rows of single pillars to support the top plate.
Step two: and arranging baffles between the roadway wall close to the goaf side in the retained roadway and the single support along the advancing direction of the working face, and tightly nailing two adjacent baffles by iron nails.
Step three: and starting filling equipment, and sequentially filling waste rocks from far to near on one side far away from the single prop in the goaf to form a waste rock filling body.
Step four: and when the waste rock is filled to the goaf at the entry retaining position, starting the waste rock conveyor and the cement conveyor to mix the waste rock and the cement, and filling the mixed waste rock cement material into the goaf close to the entry retaining position.
Step five: and (3) after the gangue cement material is filled into the goaf and is solidified and cemented, moving the filling support backwards, repeating the step (3) to the step (4), and continuously filling the working surface until the whole working surface filling wall body is formed into a gangue filling body and a cemented body.
Step six: and after the filled wall is fully solidified and stabilized, recovering part or all of the single pillars in the row of single pillars close to the middle part in the entry and the corresponding hinged top beams.
Preferably, in the step one, one of the two rows of single struts is close to the filling wall, and the other row is 2400mm away from the outer side of the filling wall; the distance between two adjacent single support columns in the same row of single support columns is 800 mm.
Preferably, in the second step, after the baffle is installed, steel beams are additionally arranged between the single pillars and the baffle, anchor nets are laid, and wood pillars are additionally arranged to reinforce the lateral support of the roadside filling body.
Preferably, after the baffle is installed, a metal net is laid in the retained roadway at a position 7-8m away from the early-stage crushing starting position, and the width of the metal net is greater than or equal to 3.0 m.
Preferably, the top width of the filling wall is greater than or equal to 3000 mm.
Compared with the prior art, the construction method of the gob-side entry retaining roadside support body based on the gangue cement-based material has the advantages that:
(1) the invention is suitable for solid filling working faces, and adopts a method of combining a single prop baffle and a rammed cement body for entry retaining to carry out gob-side entry retaining under the consideration of the factors of the support strength of the entry retaining initial stage, the working strength of workers and the like. The single support column supports are hinged with the top beam or the steel beam, so that the temporary support effect can be realized, and the stability of the roadway can be maintained; after the cementing material is tamped, the effect of increasing the supporting strength can be rapidly achieved, the time for waiting for final setting in cemented filling is shortened, the initial bearing capacity is strong, and the roadway retaining effect is good.
(2) The invention avoids the operation procedure of building the gangue bag wall, shortens the construction period, reduces the labor intensity of workers and obviously improves the mechanization level of gob-side entry retaining operation of the filling coal face.
(3) The invention changes the filling material into cement-based material by using the transportation system of the solid filling hydraulic support, and can add water in the transportation process, thereby simplifying the process and equipment.
(4) According to the invention, no single prop is required to be erected in the goaf, the operation is simpler and safer, and the roadway retaining effect is better.
Drawings
For a clearer explanation of the embodiments or technical solutions of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for a person skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a top view of the construction method of the gob-side entry retaining roadside support body disclosed by the invention.
Fig. 2 is a left side view of the gob-side entry retaining roadside support body construction method disclosed by the invention.
The part names represented by the numbers or letters in the drawings are:
1-a monolithic pillar; 2-hinged top beam; 3-a baffle plate; 4-filling the stent; 5, a self-moving type gangue transfer machine; 6-a porous bottom discharge conveyor; 7-a gangue filling body; 8-tamping the cemented body; 9-metal mesh.
Detailed Description
The following provides a brief description of embodiments of the present invention with reference to the accompanying drawings. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without any inventive work belong to the protection scope of the present invention.
Fig. 1-2 show preferred embodiments of the invention, which are each parsed in detail from different perspectives.
As shown in fig. 1 and 2, the method for constructing the gob-side entry retaining roadside support based on the gangue cement-based material comprises the following steps:
the method comprises the following steps: two rows of mechanical constant-resistance single pillars 1 are arranged in the entry retaining along the advancing direction of the working face, and hinged top beams 2 or steel beams perpendicular to the advancing direction of the working face are horizontally arranged above the two rows of single pillars 1 to support the top plate. One of the two rows of single struts 1 is close to the filling wall body, and the other row is 2400mm away from the outer side of the filling wall body. The column distance between two adjacent single support columns 1 in the same row of single support columns 1 is 800 mm.
Step two: and arranging baffle plates 3 between the wall of the roadway close to the goaf side in the retained roadway and the single support 1 along the advancing direction of the working face, and tightly nailing the adjacent baffle plates 3 by iron nails. The baffle 3 is a waste rock protection plate and is used for maintaining the tamping space of the roadside filling body. After the baffle 3 is installed, in order to be matched with the baffle 3 for reasonable support, the single prop 1 is additionally arranged according to the field condition, and support of each baffle 3 is ensured. Meanwhile, steel beams, anchor nets or wood pillars are additionally arranged between the single pillars 1 and the baffles 3 in the entry retaining with large mine pressure, and the lateral support of the filling body beside the roadway is further enhanced. After the baffle 3 is installed, laying a metal net 9 at a position 7-8m away from the early-stage top crushing starting position in the retained roadway, wherein the width of the metal net 9 is more than or equal to 3.0 m.
Step three: and (3) starting filling equipment, and sequentially filling the gangue on one side, far away from the single prop 1, in the goaf from far to near to form a gangue filling body 7.
Step four: when the waste rock is filled to a goaf area at the entry retaining position, a porous bottom-dump conveyor 6, a self-moving waste rock transfer conveyor 5 and a spiral conveyor are used for respectively transporting the waste rock and cement, then the waste rock and the cement are mixed, and the mixed waste rock cement material is filled into the goaf area close to the entry retaining. Specifically, when gangue is filled to a goaf at the entry retaining position, the porous bottom-dump conveyor 6 and the self-moving gangue transfer conveyor 5 are started to transport the gangue, the screw conveyor is started to convey cement into the cement hopper, when the gangue is transported to the cement mixing device, the cement hopper and the water spraying device are opened, gangue and fly ash are uniformly mixed according to the ratio of 6.9:0.9:0.2:2, gangue cement materials after mixing are filled into a goaf close to the entry retaining position, and then the gangue cement materials are compacted by a compactor at the rear part of the filling support 4, so that the mixed materials are guaranteed to be compacted and fully abut against the top, and a compacted and cemented body 8 is formed. The width of the waste filling body 7 is 3.6 meters, and the width of the rammed cement body 8 is 3.0 meters.
Step five: and after the gangue cement material is filled into the goaf and is solidified and cemented, moving the filling support 4 backwards, repeating the steps 3-4, and continuously filling the working surface until the whole working surface filling wall body is formed into a gangue filling body 7 and a tamped cemented body 8, wherein the abutting width of the filling wall body is more than or equal to 3000 mm.
Step six: and after the filled wall is fully solidified and stabilized, recovering part or all of the single pillars 1 in the row of single pillars 1 close to the middle part in the entry and the corresponding hinged top beams 2.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (5)

1. A gob-side entry retaining roadside support body construction method based on gangue cement-based materials is characterized by comprising the following steps:
the method comprises the following steps: two rows of mechanical constant-resistance single pillars (1) are arranged in the entry retaining along the advancing direction of the working face, and a hinged top beam (2) is arranged above the two rows of single pillars (1) to support a top plate;
step two: a baffle (3) is arranged between the wall of the roadway close to the goaf side in the retained roadway and the single support (1) along the advancing direction of the working face, and the two adjacent baffles (3) are tightly nailed by iron nails;
step three: starting filling equipment, and sequentially filling waste rocks from far to near on one side, far away from the single prop (1), in the goaf to form a waste rock filling body (7);
step four: when the waste rock is filled to the goaf at the entry retaining position, starting a waste rock conveyor and a cement conveyor to mix the waste rock and the cement, and filling the mixed waste rock cement material into the goaf at the position close to the entry retaining position;
step five: after the gangue cement material is filled into the goaf and is solidified and cemented, moving the filling support (4) backwards, repeating the steps 3-4, and continuously filling the working surface until the whole working surface filling wall body is formed into a gangue filling body (7) and a tamped cemented body (8);
step six: and after the filled wall is fully solidified and stabilized, recovering part or all of the single pillars (1) in the row of single pillars (1) close to the middle part in the entry and the corresponding hinged top beams (2).
2. The method for constructing the gob-side entry retaining roadside supporter based on gangue cement-based materials according to claim 1, wherein in the step one, one of two rows of single pillars (1) is close to the filling wall, and the other row is 2400mm away from the outside of the filling wall; the column distance between two adjacent single columns (1) in the same row of single columns (1) is 800 mm.
3. The method for constructing the gob-side entry retaining roadside support based on the gangue cement-based materials according to claim 1, wherein in the second step, after the baffles (3) are installed, steel beams are additionally arranged between the single pillars (1) and the baffles (3), anchor nets are laid, and wood pillars are additionally arranged to reinforce the lateral support of the roadside packing body.
4. The gob-side entry retaining roadside supporter construction method based on gangue cement-based materials according to claim 3, characterized in that after the installation of the baffle (3) is completed, a metal mesh (9) is laid in the entry at a position 7-8m from the early top crushing start position, and the width of the metal mesh (9) is greater than or equal to 3.0 m.
5. The method for constructing the gob-side entry retaining roadside supporter based on gangue cement-based materials as claimed in claim 1, wherein the top contact width of the filling wall is not less than 3000 mm.
CN202011002305.8A 2020-09-22 2020-09-22 Gob-side entry retaining roadside support body construction method based on gangue cement-based material Pending CN112112672A (en)

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