CN115788498B - Mechanical tunneling and supporting method in filling body - Google Patents
Mechanical tunneling and supporting method in filling body Download PDFInfo
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- CN115788498B CN115788498B CN202310048500.1A CN202310048500A CN115788498B CN 115788498 B CN115788498 B CN 115788498B CN 202310048500 A CN202310048500 A CN 202310048500A CN 115788498 B CN115788498 B CN 115788498B
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Abstract
The invention provides a mechanical tunneling and supporting method in a filling body, which relates to the technical field of mining and comprises the following steps: tunneling the filling body by mechanical rock breaking tunneling equipment to form a tunnel; shotcrete support is carried out on the roadway; anchoring and supporting the roadway after the concrete is sprayed; through anchor support, make the support more stable, reduce the risk that the later stage is unstable, can avoid constructor to construct for a long time after spraying concrete and exist the risk, reduce the potential safety hazard, alleviate the work progress danger that exists among the prior art and later stage appear falling easily, have the technical problem of potential safety hazard, reached the risk that reduces the work progress, avoid the technological effect that later stage collapses simultaneously.
Description
Technical Field
The invention relates to the technical field of mining, in particular to a mechanical tunneling and supporting method in a filling body.
Background
At present, the underground is usually provided with a plurality of ore veins, in order to facilitate ore transportation in mining, a vein penetrating connecting channel for communicating an upper disc with a lower disc is generally arranged in a specific area, and the connecting channel can be arranged in a safe ore pillar or a mined goaf. If the connecting channel is arranged in the safe ore pillar, the ore pillar cannot be mined in order to ensure the stability and the safety. In order to facilitate recovery of ore resources, a method of arranging a drift channel in a goaf after mining of an ore body is common. If the blasting method is adopted for mining, the blasting shock waves generated during the mining of the pulse-penetrating roadway by the blasting method not only damage the surface of the filling body, but also damage the inside of the filling body, and the blasting shock waves seriously damage the integrity of the filling body, so that the difficulty is brought to the selection of the subsequent supporting mode and the supporting safety.
In the prior art, a connecting channel is generally constructed in advance by utilizing a steel structure and concrete in a goaf, constructors are required to enter the goaf for construction, steel structure frameworks are abutted in the connecting channel and concrete is poured, and filling is performed after concrete curing is completed.
However, the construction of the pre-constructed road is threatened by the rocks which can fall off from the top and the side walls of the goaf, construction personnel are dangerous for long-term construction, in addition, the pre-constructed roadway is threatened by the rocks which can fall off from the top and the side walls of the goaf, and the pre-constructed roadway is required to bear the impact stress and the self-weight stress of the filling body on the roadway, so that potential safety hazards exist.
Disclosure of Invention
The invention aims to provide a mechanical tunneling and supporting method in a filling body, which is used for relieving the technical problems that the danger of the construction process and the falling off easily occur in the later period in the prior art and potential safety hazards exist.
The invention provides a mechanical tunneling and supporting method in a filling body, which comprises the following steps:
tunneling the filling body by mechanical rock breaking tunneling equipment to form a tunnel;
shotcrete support is carried out on the roadway;
and (5) carrying out anchoring and supporting on the roadway after the concrete is sprayed.
In an alternative embodiment, the step of anchoring the support comprises:
and anchoring the sprayed roadway by adopting an anchor rod.
In an alternative embodiment, the anchor rod comprises a tube seam anchor rod, the step of tube seam anchor rod comprising:
the pipe seam anchor rod is driven into a roadway section and is divided into a primary anchoring section and a secondary anchoring section;
after the pipe seam anchor rod is compressed, the preliminary anchoring section is driven into a roadway;
and (3) releasing the compression of the pipe seam anchor rod, and then driving the remaining secondary anchoring section into the roadway.
In an alternative embodiment, the primary anchor section is four fifths of the driven roadway section and the secondary anchor section is one fifth of the driven roadway section.
In an alternative embodiment, the step of shotcrete supporting the roadway includes:
and spraying fiber concrete with the thickness of at least 30mm on the roadway, wherein the strength of the fiber concrete is at least C20, and curing after spraying.
In an alternative embodiment, the method further comprises the steps of:
and (5) secondarily spraying concrete to the tunnel after the anchoring support.
In an alternative embodiment, the step of anchoring the anchor rod further comprises:
the anchor rod comprises an expansion pipe anchor rod, the expansion pipe anchor rod is adopted to anchor in the roadway after the injection, and the expansion pipe anchor rod expands after extending into the roadway.
The invention provides a mechanical tunneling and supporting method in a filling body, which comprises the following steps: tunneling the filling body by mechanical rock breaking tunneling equipment to form a tunnel; shotcrete support is carried out on the roadway; anchoring and supporting the roadway after the concrete is sprayed; through anchor support, make the support more stable, reduce the risk that later stage drops, can avoid constructor to construct the risk that exists for a long time after the shotcrete, reduce the potential safety hazard, alleviate the work progress danger that exists among the prior art and later stage appear falling easily, have the technical problem of potential safety hazard, reached the risk that reduces the work progress, avoid the technical effect that later stage collapses simultaneously.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
FIG. 1 is a cross-sectional view of a method for mechanical tunneling and support in a body of a filler provided by an embodiment of the present invention;
FIG. 2 is a top view of a method of mechanical tunneling and supporting in a body of a filler according to an embodiment of the present invention;
FIG. 3 is a schematic view of a structure of an anchor rod for a mechanical tunneling and supporting method in a packer according to an embodiment of the present invention;
FIG. 4 is a schematic view of an expansion assembly of a mechanical tunneling and supporting method in a filling body according to an embodiment of the present invention;
fig. 5 is a schematic structural view of an anchor rod and expansion assembly for a method of mechanical driving and supporting in a packing according to an embodiment of the present invention.
Icon: 1-roadway; 2-anchor rod; 3-concrete; 4-mechanical rock breaking tunneling equipment; a 5-expansion assembly; 6-an outer tube; 7-inner core.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the present invention, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present invention and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal," "vertical," "overhang," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Some embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other without conflict.
As shown in fig. 1 to 5, the method for mechanical tunneling and supporting in a filling body provided by the embodiment of the invention comprises the following steps: the mechanical rock breaking tunneling equipment 4 tunnels the filling body to form a tunnel 1; shotcrete 3 supporting is carried out on the roadway 1; and (5) carrying out anchoring and supporting on the roadway 1 after the concrete 3 is sprayed.
In this embodiment, the mechanical rock breaking tunneling device 4 may adopt a tunneling machine, a channel formed after the mechanical rock breaking tunneling device 4 is tunneling 1, the tunneling 1 is arranged in an extending manner along a horizontal direction, or is arranged in an inclined manner, in a supporting process, the inner wall of the tunneling 1 is sprayed with concrete 3, wherein the thickness of the sprayed concrete 3 is not less than 30mm, the strength of the concrete 3 is not less than C20, the spraying position can be the top, the side wall and the bottom of the tunneling 1, after the concrete 3 is sprayed for the first time, the inner wall of the tunneling 1 is anchored and supported, so that the tunnel 1 is prevented from collapsing, the risk in the construction process is reduced, and meanwhile, the later tunnel is prevented from being collapsed.
The mechanical tunneling and supporting method in the filling body provided by the embodiment of the invention comprises the following steps: the mechanical rock breaking tunneling equipment 4 tunnels the filling body to form a tunnel 1; shotcrete 3 supporting is carried out on the roadway 1; anchoring and supporting the roadway 1 after the concrete 3 is sprayed; through the anchor support, make the support more stable, reduce the risk of collapsing, can avoid constructor's risk of constructing for a long time after spraying concrete 3, reduce the potential safety hazard, alleviate the construction process danger that exists among the prior art and later stage appear droing easily, have the technical problem of potential safety hazard, reached the risk that reduces the construction process, avoid the technical effect that later stage collapses simultaneously.
In an alternative embodiment, the step of anchoring the support comprises: after the concrete 3 is sprayed, the anchoring is performed in the roadway 1 by the anchor rods 2.
In this embodiment, the anchor rod 2 is elongated, after the concrete 3 is sprayed, the mesh is covered on the concrete 3, the anchor rod 2 is driven in, the tail of the driven anchor rod 2 is connected with the anchoring mesh, the anchor rod 2 is fixed through the roadway 1, the roadway 1 is fixed through the anchor rod 2 and the mesh, and meanwhile, the concrete 3 is fixed without falling off.
Optionally, the anchor rods 2 are provided in a plurality, and the vertical plane along the tunneling direction of the mechanical rock breaking tunneling equipment 4 is used as a group, each group is provided with a plurality of anchor rods 2, the plurality of anchor rods 2 are uniformly arranged at intervals along the inner wall of the roadway 1, every two adjacent anchor rods 2 are not more than 3m, the plurality of groups of anchor rods 2 are arranged at intervals along the tunneling direction of the mechanical rock breaking tunneling equipment 4, and the distance between every two adjacent anchor rods 2 is not more than 4m.
In an alternative embodiment, the step of anchoring the anchor rod 2 includes: the sprayed roadway 1 is anchored by a pipe seam anchor rod 2, and the pipe seam anchor rod 2 is higher than the sprayed concrete 3 after the anchoring.
In this embodiment, after the concrete 3 is injected into the roadway 1, the pipe joint anchor rod 2 is driven into the roadway 1, the height of the end face of the pipe joint anchor rod 2 after the driving is higher than that of the injected concrete 3, and the pipe joint anchor rod 2 is connected with the net sheet through the end face of the pipe joint anchor rod 2, wherein the length of the pipe joint anchor rod 2 is at least 1m.
In an alternative embodiment, the step of anchoring the seam anchor 2 comprises: driving a pipe seam anchor rod 2 into a roadway 1 section to divide a primary anchoring section and a secondary anchoring section; after the pipe seam anchor rod 2 is compressed, the preliminary anchoring section is driven into the roadway 1; the compression of the seam anchor 2 is released and the remaining secondary anchoring section is then driven into the roadway 1.
In this embodiment, the pipe seam anchor 2 is driven into the roadway 1 except for the leaked portion, the primary anchoring section is arranged at one end of the first entering roadway 1, the secondary anchoring section is arranged adjacent to the primary anchoring section, in the actual use process, the pipe seam anchor 2 is provided with a pipe seam penetrating along the length direction of the pipe seam anchor 2, so that the diameter of the pipe seam anchor 2 can be compressed by external force to change, a limiting ring is arranged at the conical end before driving, the inner diameter of the limiting ring is smaller than the outer diameter of the pipe seam anchor 2 in a release state, the limiting ring can enable the pipe seam anchor 2 to be compressed, at the moment, the pipe seam anchor 2 is driven into the roadway 1 until the primary anchoring is completed, so that the pipe seam anchor 2 can be driven into the roadway 1 more easily, the primary positioning effect is achieved, then the limiting ring is removed, the pipe seam anchor 2 is expanded, and the remaining secondary anchoring section is driven into the roadway through the anchoring of the pipe seam anchor 2 with two different diameters, so that the pipe seam anchor 2 is connected with the roadway 1 more tightly.
In an alternative embodiment, the primary anchor segment is less than four fifths of the segment driven into roadway 1 and the secondary anchor segment is greater than one fifth of the segment driven into roadway 1.
In this embodiment, the primary anchoring section occupies four fifths of the section driven into the roadway 1, so that the driving process is smoother, and the secondary anchoring section occupies one fifth of the section driven into the roadway 1, so that the anchor rod 2 is more stable after secondary anchoring.
In an alternative embodiment, the step of shotcrete 3 supporting the roadway 1 comprises: the roadway 1 is sprayed with fiber concrete 3 with the thickness of at least 30mm, the strength of the fiber concrete 3 is at least C20, the maintenance is carried out after spraying, and meanwhile, the roadway 1 after the anchoring of the anchor rod 2 can be subjected to secondary spraying of the fiber concrete 3.
In this embodiment, the primary sprayed concrete 3 and the secondary sprayed concrete 3 may be concrete 3 with strength of at least C20, the spraying thickness of both times may be at least 30mm, the tunneling method in the filling body may be implemented by tunneling and supporting circulation until the tunnel 1 is constructed, or by synchronizing tunneling and supporting to the tunnel 1.
In an alternative embodiment, the step of anchoring the mesh by the anchor rod 2 further comprises: the injected roadway 1 is anchored by adopting the expansion anchor rod 2, the expansion anchor rod 2 stretches into the roadway 1 to expand, and the expansion anchor rod 2 is higher than the injected concrete 3 after anchoring.
In this embodiment, the expansion pipe end of the expansion pipe anchor rod 2 is firstly contacted with the roadway 1 and is driven into the roadway 1, the end face of the pipe joint anchor rod 2 is higher than the first sprayed concrete 3 after being driven into the roadway 1, then the end face of the pipe joint anchor rod 2 can be connected with the net sheet, and the expansion pipe anchor rod 2 is expanded after being driven into the roadway 1, so that the connection between the expansion pipe anchor rod 2 and the roadway 1 is more compact.
In an alternative embodiment, the step of anchoring the expanded tubular section 2 comprises: punching holes on the inner wall of the sprayed concrete 3 according to the length of the expanded pipe anchor rod 2; arranging a tip of at least 0.2m at the front end of the expanded pipe anchor rod 2, and extending the expanded pipe anchor rod 2 into the punching hole; the expansion assembly 5 stretches into the expansion anchor rod 2 to expand and push the tip end of the front end of the expansion anchor rod 2 to move in the direction away from the axis of the expansion anchor rod 2.
In this embodiment, the front end of the expanded anchor rod 2 is set to at least two triangular tips and is uniformly set along the axis of the expanded anchor rod 2, in the anchoring process of the expanded anchor rod 2, a hole is punched at a preset position, the length of the hole is 1cm shorter than that of the expanded anchor rod 2, then the expanded anchor rod 2 is extended from the hole, after the triangle at the front end of the expanded anchor rod 2 bottoms out, the expansion assembly 5 is extended into the triangular tips from the expanded anchor rod 2, then the expansion assembly 5 is started to expand and is abutted against the inner wall of the tips, so that the expansion assembly 5 pushes the tips to expand to complete the expansion and anchoring processes, and the anchor rod 2 is anchored in a pipe expanding manner.
In an alternative embodiment, the step of expanding the expansion assembly 5 into the expanded tubular anchor 2 comprises: the expansion assembly 5 is contracted after expansion is completed and is withdrawn from the expanded bolt 2.
In this embodiment, the expansion assembly 5 may adopt an outer tube 6 and an inner core 7, the inner core 7 is disposed in the outer tube 6 and slides along the axial direction thereof with respect to the outer tube 6, a vertical push plate is disposed at the front end of the inner core 7, two cams are disposed on the outer tube 6 corresponding to the push plate, the push plate can push the two cams away from each other, in the expansion process, the expansion assembly 5 stretches into the expansion anchor rod 2, and when the two cams correspond to the tip, the inner core 7 is pushed to push the push plate and the two cams, at this time, the two cams squeeze the tip to expand, thereby achieving the purpose of expansion, and after the expansion is completed, the inner core 7 is pulled back, at this time, the push plate is retracted, and the outer tube 6 is pulled to bring the two cams close to each other, so that the expansion assembly 5 can withdraw from the expansion anchor rod 2, the expansion assembly 5 can be recycled, and the cost is saved.
In this embodiment, the mesh may be a reinforced bar band or a reinforced bar net, and when the small area in the roadway 1 is supported, the reinforced bar band may be used, and when the large area in the roadway 1 is required to be supported, the reinforced bar net may be used, so that the support is more flexible, and the working hours and materials are saved.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (5)
1. The mechanical tunneling and supporting method in the filling body is characterized by comprising the following steps:
tunneling the filling body by mechanical rock breaking tunneling equipment to form a tunnel;
shotcrete support is carried out on the roadway;
anchoring and supporting the roadway after the concrete is sprayed;
the anchoring support comprises the following steps:
anchoring the sprayed roadway by adopting an anchor rod;
the anchor rod comprises a pipe seam anchor rod, and the anchoring step of the pipe seam anchor rod comprises the following steps:
the pipe seam anchor rod is driven into a roadway section and is divided into a primary anchoring section and a secondary anchoring section;
after the pipe seam anchor rod is compressed, the preliminary anchoring section is driven into a roadway;
and (3) releasing the compression of the pipe seam anchor rod, and then driving the remaining secondary anchoring section into the roadway.
2. The method of mechanical driving and supporting in a filling body according to claim 1, wherein the primary anchoring section occupies less than four fifths of the driving section, and the secondary anchoring section occupies more than one fifth of the driving section.
3. A method of mechanical driving and supporting a roadway in a filling body according to any one of claims 1 to 2, wherein the step of shotcrete supporting the roadway comprises:
and spraying fiber concrete with the thickness of at least 30mm on the roadway, wherein the strength of the fiber concrete is at least C20, and curing after spraying.
4. The method of intra-filler mechanical tunneling and supporting according to claim 1, further comprising the steps of:
and (5) secondarily spraying concrete to the tunnel after the anchoring support.
5. A method of mechanical driving and supporting in a filling body according to claim 1, wherein the bolt further comprises a tube-expanded bolt, the step of anchoring the tube-expanded bolt comprising:
and anchoring the sprayed roadway by adopting an expansion pipe anchor rod, and expanding the expansion pipe anchor rod after the expansion pipe anchor rod stretches into the roadway.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310048500.1A CN115788498B (en) | 2023-01-31 | 2023-01-31 | Mechanical tunneling and supporting method in filling body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310048500.1A CN115788498B (en) | 2023-01-31 | 2023-01-31 | Mechanical tunneling and supporting method in filling body |
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| Publication Number | Publication Date |
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| CN115788498A CN115788498A (en) | 2023-03-14 |
| CN115788498B true CN115788498B (en) | 2023-05-16 |
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| CN202310048500.1A Active CN115788498B (en) | 2023-01-31 | 2023-01-31 | Mechanical tunneling and supporting method in filling body |
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Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101906977B (en) * | 2010-07-21 | 2012-05-23 | 中国矿业大学(北京) | Method for preventing and treating large deformation and collapse of softrock tunnel |
| CN103195441B (en) * | 2013-04-01 | 2016-08-31 | 平顶山天安煤业股份有限公司 | A kind of supporting and reinforcing structure of coal mine tunnel and construction technology thereof |
| CN211648216U (en) * | 2020-01-14 | 2020-10-09 | 山东嘉浩矿山机械有限公司 | Self-expansion type pipe seam anchor rod |
| CN212177190U (en) * | 2020-05-26 | 2020-12-18 | 宜昌百川矿山机械有限公司 | Pipe seam anchor rod convenient to disassemble and assemble |
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