CN112627892A - Closed wall construction method based on reinforcing mesh and high-water-content material - Google Patents
Closed wall construction method based on reinforcing mesh and high-water-content material Download PDFInfo
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- CN112627892A CN112627892A CN202011516335.0A CN202011516335A CN112627892A CN 112627892 A CN112627892 A CN 112627892A CN 202011516335 A CN202011516335 A CN 202011516335A CN 112627892 A CN112627892 A CN 112627892A
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- wall
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- mixing barrel
- pipeline
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/103—Dams, e.g. for ventilation
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21F15/02—Supporting means, e.g. shuttering, for filling-up materials
- E21F15/04—Stowing mats; Goaf wire netting; Partition walls
Abstract
The invention provides a construction method of a closed wall based on a reinforcing mesh-high-water material, which comprises the following steps that main construction equipment comprises a material mixing barrel, a stirrer, a grouting pump, a stirrer and the like, and the equipment is connected into a pumping system through a slurry conveying pipeline; the invention mainly comprises the following steps: determining the proportion of the high-water material slurry and the width of the sealing wall, forming a space of the sealing wall, preparing the high-water material slurry, constructing a solid body of the sealing wall by grouting, constructing a counter-pull anchor rod to improve the bearing capacity of the wall body and the like. Compared with the existing means, the novel airtight wall construction technology provided by the invention has the advantages of high construction speed, good sealing effect, high wall strength and the like.
Description
Technical Field
The invention belongs to the technical field of mineral engineering, and particularly relates to a method for constructing a closed wall based on a reinforcing mesh-high-water material.
Background
The construction of the sealing wall is usually carried out at the positions of a working face double-lane tunneling connection lane, a goaf and stoping lane intersection, a gob-side entry retaining roadside filling body and the like under a coal mine, and the sealing wall mainly aims to prevent harmful gas leakage, air return lane cross ventilation, goaf communication air spontaneous combustion and the like and also has the functions of supporting an upper top plate and relieving the pressure of a coal wall.
The traditional airtight wall construction usually adopts a brick-laying form, generally a 'two-four wall' (the width of a wall body is equal to 1 time of the length of a brick block and is 24 cm) or a 'pseudo-ginseng wall' (the width of a wall body is equal to 1.5 times of the length of the brick block and is added with a small part of concrete and is 37 cm), the construction speed is slow, the period is long, construction materials such as bricks, concrete and the like need to be frequently carried, the labor resources are seriously wasted, and the production efficiency is restricted. In recent years, some mines try to adopt a method for constructing a sealing wall by adopting a high-water material, wherein the material is divided into a material A and a material B, slurry formed by mixing the material A and the material B with water respectively is not solidified within 24 hours, but the two slurries are preliminarily solidified within 30 minutes after being mixed by equal mass. The high-water material has the advantages of short condensation time, strong deformation resistance, long conveying distance and the like, and can play a better sealing role when the deformation of a construction area is serious. However, high water materials also have some disadvantages. Taking a high-water material with a water-cement ratio of 1.5:1 as an example, the initial setting strength of the material is 4-6 MPa, and the stable strength of the material is 9-11 MPa, which is lower than the strength (20 MPa) of mining C20 concrete and the strength (15 MPa) of common hard coal blocks. Therefore, in a strong mine pressure working face with large vertical stress and burial depth, the problems of instability, collapse and the like of the sealing wall can occur by directly adopting a high-water material, and a sealing wall construction technology with higher adaptability needs to be explored.
Disclosure of Invention
The invention provides a method for constructing a sealing wall based on a reinforcing mesh-high water material based on a high water material as a foundation and combined with concrete construction requirements under a coal mine, and compared with the prior art, the method has the advantages of high construction speed, good sealing effect, high wall strength and the like.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a method for constructing a closed wall based on a reinforcing mesh and a high-water material comprises the following steps:
firstly, preparing equipment such as a material A mixing barrel, a material B mixing barrel, a grouting pump, a stirrer and the like, and connecting the equipment through a material A pipeline, a material B pipeline, a high-water material mixed liquid pipeline and a pipeline interface; additionally, a stirrer and a pneumatic anchor cable drilling machine are respectively arranged near the first material mixing barrel and the space constructed by the sealing wall;
secondly, determining the water-cement ratio of the high-water material slurry to be 1.2: 1-2.5: 1 and the width of the wall body to be 0.5-1.5 m according to the buried depth and the vertical ground stress of the mine;
thirdly, using an anchor cable drilling machine to construct and drill a hole on a top plate of a sealing wall area expected to be constructed in the connection roadway and installing an anchor rod, fixing a reinforcing mesh at the tail end of the anchor rod of the top plate through an iron wire, fixing coal pillars in the length direction of the reinforcing mesh by adopting the same method, and hanging filling bags on two sides of the reinforcing mesh to form a space for constructing the sealing wall;
step four, respectively pouring the high-quality water materials A, B and water with different water-cement ratios determined in the step two into a material A mixing barrel and a material B mixing barrel, fully and uniformly mixing by using a stirrer, and then placing for later use;
step five, using a grouting pump to convey the material slurry into a mixing barrel of a mixer through a material A pipeline and a material B pipeline, uniformly mixing, conveying the material slurry into a filling bag through a high-water material mixed liquid pipeline until the filling space is filled with liquid and the material slurry is contacted with a top plate, and closing the grouting pump to finish the construction of the sealing wall of the connection roadway;
step six, under the condition that the deep mine or the ground stress is more than 15MPa, additionally punching opposite pull anchor rods on the closed wall to apply transverse restraint, forming a double reinforcing bearing effect of a reinforcing mesh and the opposite pull anchor rods, and increasing the deformation resistance of the closed wall;
and seventhly, repeating the third step to the sixth step in the next connecting lane, and continuing to perform the sealing wall construction of the next-stage connecting lane.
Further, in the second step, the vertical ground stress of the mine is in direct proportion to the buried depth of the coal seam, and the larger the buried depth is, the larger the vertical ground stress is.
Furthermore, in the fourth step, the material mixing barrel for the material A is separated from the material mixing barrel for the material B, so that the slurry is prevented from contacting to form solids.
Further, in the fourth step, after the stirrer stirs the slurry in one mixing barrel, the stirrer is cleaned, and then the stirring of the next mixing barrel is performed.
Furthermore, in the fifth step, after the construction of the sealing wall is completed in stages or completely, the stirrer, the high-water material mixed liquid pipeline, parts and interfaces thereof need to be completely cleaned, so that the high-water material slurry is prevented from solidifying and blocking the pipeline.
Compared with the prior art, the invention has the beneficial effects that:
1. the mechanized construction is realized, the equipment does not need to be moved after being installed once, the mechanized filling efficiency of the airtight wall is far higher than that of a traditional brick laying mode, less manpower resources are used, and the construction speed is higher.
2. The filling bag and the high-water material filling body can play a role in sealing and isolating harmful gas in the goaf, and coal pillars at two ends of the sealing wall can deform to present an irregular surface in actual mining.
3. The steel bar mesh and the opposite pull anchor rods are constructed in the space of the closed wall, so that the transverse opposite pull anchor rods and the longitudinal steel bar mesh of the high-water-material closed wall are strengthened in bearing, the defect of low strength of high-water materials is overcome, and the strength of the closed wall is improved.
Drawings
FIG. 1 is a schematic diagram of a high water material pumping system according to the present invention;
FIG. 2 is a schematic view of the arrangement orientation of the sealing wall of the working face connecting roadway according to the invention;
FIG. 3 is a schematic view of the construction of the connecting roadway closing wall according to the present invention;
FIG. 4 is a schematic cross-sectional view of the enclosure wall A-A;
FIG. 5 is a cross-section B-B of the enclosure wall;
FIG. 6 is a schematic view of a reinforcing support for a counter-pull anchor rod;
in the figure, 1.1-first material mixing barrel, 1.2-second material mixing barrel, 1.3-stirrer, 1.4-grouting pump, 1.5-stirrer (containing mixing barrel), 1.6-sealing wall construction space, 1.7-first material pipeline, 1.8-second material pipeline, 1.9-high water material mixed liquid pipeline, 1.10-pipeline interface, 2.1-working face, 2.2-goaf, 2.3-main transportation roadway, 2.4-abandonment section main transportation roadway, 2.5-auxiliary transportation roadway, 2.6-communication roadway, 2.7-sealing wall entity, 2.8-expected constructed sealing wall, 2.9-coal pillar, 2.10-filling bag and 2.11-reinforcing mesh.
Detailed Description
In order to facilitate an understanding of the invention, the invention will now be described more fully hereinafter with reference to the accompanying drawings, in which several embodiments of the invention are shown, but which may be embodied in different forms and not limited to the embodiments described herein, but which are provided so as to provide a more thorough and complete disclosure of the invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, and the knowledge of the terms used herein in the specification of the present invention is for the purpose of describing particular embodiments and is not intended to limit the present invention, and the term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
In the embodiment, referring to fig. 1-6, the selected geological condition of the coal mine is a certain mine in Shanxi, the buried depth of the mine is 650m, and the vertical ground stress is 15.6 MPa; the mining height of the working face is equal to the thickness of the coal bed and is 3.5 m; the width of the connecting roadway is 5m, the length of the connecting roadway is equal to the width of the coal pillar, and the width of the connecting roadway is 20 m; and a main transport roadway and an auxiliary transport roadway of the working face are provided with one connecting roadway every 50 m. A method for constructing a closed wall based on a reinforcing mesh and a high-water material comprises the following steps: preparing various devices for constructing the sealing wall, determining the proportion of high-water material slurry and the width of the sealing wall, forming a space of the sealing wall, preparing the first material slurry and the second material slurry, constructing a solid body of the sealing wall by grouting, constructing opposite-pulling anchor rods to improve the strength of the sealing wall and continuously constructing the sealing wall, wherein the specific implementation mode is as follows:
1. preparing various devices for constructing the airtight wall: preparing equipment such as a material mixing barrel A1.1, a material mixing barrel B1.2, an injection pump 1.4, a stirrer 1.5 and the like, and connecting the equipment through a material mixing pipeline A1.7, a material mixing pipeline B1.8, a high-water material mixed liquid pipeline 1.9 and a pipeline connector 1.10; and additionally, a stirrer 1.3 and a pneumatic anchor cable drilling machine are respectively arranged near the first material mixing barrel 1.1 and the closed wall construction space 1.6.
2. Determining the high-water material slurry ratio and the width of the sealing wall: according to the buried depth and the vertical ground stress of the mine, the water-cement ratio of the high-water material slurry is 1.2: 1-2.5: 1, and the width of the wall body is 0.5-1.5 m.
It should be noted that the vertical ground stress of the mine is in direct proportion to the coal seam burial depth, and the larger the burial depth is, the larger the vertical ground stress is; the lower the water-cement ratio of the high-water material slurry and the larger the width of the sealing wall, the stronger the vertical ground stress of the mine can be resisted, and the specific requirements are shown in the following table 1:
| buried depth (vertical ground stress) | Water cement ratio | Width of |
| Less than 200m (less than 5 MPa) | 2.5:1 | 0.5m |
| 200m~400m（5MPa~10MPa） | 2.0:1 | 0.75 m |
| 400m~600m（10MPa~15MPa） | 1.8:1 | 1.0 m |
| Below 600m (greater than 15 MPa) | 1.5:1 | 1.5 m |
TABLE 1
3. Forming a closed wall space: the top plate of the area of the sealing wall 2.8 expected to be constructed in the communication roadway 2.2 is drilled and provided with anchor rods by using an anchor cable drilling machine, the reinforcing mesh 2.11 is fixed at the tail ends of the anchor rods of the top plate through iron wires, the coal pillars 2.9 in the length direction of the reinforcing mesh 2.11 are fixed by adopting the same method, and filling bags 2.10 are hung on two sides of the reinforcing mesh 2.11 to form a sealing wall construction space 1.6.
4. Preparing material slurry A and material slurry B: high-water materials A, B and water with different qualities and determined by the ratio are respectively poured into a material A mixing barrel 1.1 and a material B mixing barrel 1.2, and are fully and uniformly mixed by a stirrer 1.3 and then are placed for standby.
In the above steps, the material mixing barrel A1.1 and the material mixing barrel B1.2 are separated to prevent slurry from contacting and forming solid, and after the slurry in one material mixing barrel is stirred by the stirrer 1.3, the next material mixing barrel is stirred after the slurry is cleaned.
5. Grouting to construct a solid of the sealing wall: and (3) conveying the material slurry to a material mixing barrel of a stirrer 1.5 through a material A pipeline 1.7 and a material B pipeline 1.8 by using a grouting pump 1.4, uniformly stirring, conveying the material slurry to a filling bag 2.10 through a high-water material mixed liquid pipeline 1.9 until the filling space is filled with the liquid and the liquid is contacted with a top plate, and closing the grouting pump 1.4 to finish the construction of the sealing wall of the connection roadway 2.2.
In the above steps, after the construction of the sealing wall is completed in stages or completely, the mixer 1.5, the high-water material mixed liquid pipeline 1.9, parts and interfaces thereof need to be cleaned completely, so as to prevent the high-water material slurry from solidifying and blocking the pipeline.
6. The construction is to drawing the stock and improving the airtight wall intensity: under the condition that the stress of a deep mine or the ground is more than 15MPa, the opposite-pulling anchor rods 2.12 are additionally arranged on the closed wall body to exert transverse restraint, so that the double strengthening bearing function of the reinforcing mesh 2.11-the opposite-pulling anchor rods 2.12 is formed, and the deformation resistance of the closed wall 2.7 is improved.
7. Continuously constructing a sealing wall: and (5) repeating the steps 3-6 in the next connecting lane, and continuing to carry out the sealing wall construction of the next-stage connecting lane.
It should be noted that only the third step and the seventh step need manual auxiliary operation, and the rest steps can realize mechanized construction, and the equipment does not need to be moved after being installed once, so that the mechanized filling efficiency of the airtight wall is much higher than that of the traditional brick laying mode, the amount of manpower resources is less, and the construction speed is faster; the filling bags and the high-water material filling bodies constructed in the third step and the fifth step can play a role in sealing and isolating harmful gas in the goaf, and coal pillars at two ends of the sealing wall can deform to present an irregular surface in actual mining; and step three and step six, respectively constructing a reinforcing mesh and a counter-pull anchor rod in the space of the closed wall to form transverse counter-pull anchor rod bearing reinforcement and longitudinal reinforcing mesh bearing reinforcement of the high-water-material closed wall, so that the defect of low strength of the high-water material is overcome, and the strength of the closed wall is improved.
The invention is described above by way of example with reference to the accompanying drawings, and it is obvious that the specific implementation of the invention is not limited by the above manner, and other supporting facilities such as a material a pipeline, a material b pipeline, a high-water material mixed liquid pipeline, a pipeline interface and the like, which are the same as the equipment requirements, meet the coal mine safety standards, the patent use requirements and the like, are within the protection scope of the invention.
Claims (5)
1. A method for constructing a closed wall based on a reinforcing mesh and a high-water material is characterized by comprising the following steps:
step one, preparing a material mixing barrel A (1.1), a material mixing barrel B (1.2), an injection pump (1.4) and a stirrer (1.5), and connecting the materials through a material mixing pipeline A (1.7), a material mixing pipeline B (1.8), a high-water material mixed liquid pipeline (1.9) and a pipeline interface (1.10); additionally, a stirrer (1.3) and a pneumatic anchor cable drilling machine are respectively arranged near the first material mixing barrel (1.1) and the closed wall construction space (1.6);
secondly, determining the water-cement ratio of the high-water material slurry to be 1.2: 1-2.5: 1 and the width of the wall body to be 0.5-1.5 m according to the buried depth and the vertical ground stress of the mine;
thirdly, constructing and drilling a hole on a top plate of a sealing wall (2.8) area expected to be constructed in the connection roadway (2.2) by using an anchor cable drilling machine, installing anchor rods, fixing a reinforcing mesh (2.11) at the tail ends of the anchor rods of the top plate through iron wires, fixing the reinforcing mesh (2.11) on coal pillars (2.9) in the length direction of the reinforcing mesh (2.11) by adopting the same method, and hanging filling bags (2.10) at two sides of the reinforcing mesh (2.11) to form a sealing wall construction space (1.6);
step four, respectively pouring the high-quality water materials A, B and water with different water-cement ratios determined in the step two into a material A mixing barrel (1.1) and a material B mixing barrel (1.2), and fully and uniformly mixing by using a stirrer (1.3) and then placing for later use;
step five, a grouting pump (1.4) is used for conveying material slurry into a material mixing barrel of a stirrer (1.5) through a material A pipeline (1.7) and a material B pipeline (1.8), the material slurry is uniformly stirred and then conveyed into a filling bag (2.10) through a high-water material mixed liquid pipeline (1.9), the grouting pump (1.4) is closed until liquid is filled in a filling space and contacts with a top plate, and the construction of the sealing wall of the connection roadway (2.2) is finished;
sixthly, under the condition that the stress of a deep mine or the ground is more than 15MPa, additionally punching a counter pull anchor rod (2.12) on the closed wall body to apply transverse restraint, forming a double reinforcing bearing function of a reinforcing mesh (2.11) -the counter pull anchor rod (2.12), and increasing the deformation resistance of the closed wall (2.7);
and seventhly, repeating the third step to the sixth step in the next connecting lane, and continuing to perform the sealing wall construction of the next-stage connecting lane.
2. The method as claimed in claim 1, wherein in the second step, the vertical stress of the mine is proportional to the depth of the coal seam, and the vertical stress is increased as the depth of the coal seam is increased.
3. The method for constructing a steel bar net-high water material-based containment wall as claimed in claim 1, wherein in the fourth step, the first material mixing barrel (1.1) is separated from the second material mixing barrel (1.2) to prevent solids from being formed due to slurry contact.
4. The method for constructing a steel bar net-high water material-based sealing wall as claimed in claim 1, wherein in the fourth step, after the mixer (1.3) completes the mixing of the slurry in one mixing barrel, the mixer is cleaned and the mixing in the next mixing barrel is performed.
5. The method for constructing a steel bar net-high water material-based containment wall as claimed in claim 1, wherein in the fifth step, after the construction of the containment wall is completed in stages or completely, the mixer (1.5), the high water material mixed liquid pipeline (1.9) and parts and joints thereof need to be cleaned completely to prevent the high water material slurry from solidifying and blocking the pipeline.
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| CN202011516335.0A CN112627892A (en) | 2020-12-21 | 2020-12-21 | Closed wall construction method based on reinforcing mesh and high-water-content material |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2096619C1 (en) * | 1996-01-29 | 1997-11-20 | Российский Университет Дружбы Народов | Method for roof control at layer-by-layer extraction of thick flat-lying coal seam |
| CN103628911A (en) * | 2013-12-06 | 2014-03-12 | 中国矿业大学 | Fully-mechanized coal mining/ caving working face sectional type gob-side entry retaining method |
| CN106050303A (en) * | 2016-07-29 | 2016-10-26 | 安徽理工大学 | Underground roadway plugging method and device |
| CN207620844U (en) * | 2017-12-14 | 2018-07-17 | 淮南矿业(集团)有限责任公司 | A kind of mine high-water material filling unit |
| CN111485947A (en) * | 2020-03-31 | 2020-08-04 | 扬州中矿建筑新材料科技有限公司 | Method for quickly closing goaf by roof cutting, pressure relief and gob-side entry retaining |
-
2020
- 2020-12-21 CN CN202011516335.0A patent/CN112627892A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2096619C1 (en) * | 1996-01-29 | 1997-11-20 | Российский Университет Дружбы Народов | Method for roof control at layer-by-layer extraction of thick flat-lying coal seam |
| CN103628911A (en) * | 2013-12-06 | 2014-03-12 | 中国矿业大学 | Fully-mechanized coal mining/ caving working face sectional type gob-side entry retaining method |
| CN106050303A (en) * | 2016-07-29 | 2016-10-26 | 安徽理工大学 | Underground roadway plugging method and device |
| CN207620844U (en) * | 2017-12-14 | 2018-07-17 | 淮南矿业(集团)有限责任公司 | A kind of mine high-water material filling unit |
| CN111485947A (en) * | 2020-03-31 | 2020-08-04 | 扬州中矿建筑新材料科技有限公司 | Method for quickly closing goaf by roof cutting, pressure relief and gob-side entry retaining |
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