CN112539073A - Grouting reinforcement method for soft rock roadway - Google Patents
Grouting reinforcement method for soft rock roadway Download PDFInfo
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- CN112539073A CN112539073A CN202011577858.6A CN202011577858A CN112539073A CN 112539073 A CN112539073 A CN 112539073A CN 202011577858 A CN202011577858 A CN 202011577858A CN 112539073 A CN112539073 A CN 112539073A
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- grouting
- roadway
- holes
- soft rock
- reinforcement method
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- 238000000034 method Methods 0.000 title claims abstract description 35
- 239000011435 rock Substances 0.000 title claims abstract description 27
- 230000002787 reinforcement Effects 0.000 title claims abstract description 19
- 238000005553 drilling Methods 0.000 claims abstract description 20
- 238000007789 sealing Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 239000011440 grout Substances 0.000 claims description 6
- 239000002002 slurry Substances 0.000 claims description 6
- 229910000831 Steel Inorganic materials 0.000 claims description 5
- 239000010959 steel Substances 0.000 claims description 5
- 239000003245 coal Substances 0.000 claims description 4
- 238000009826 distribution Methods 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 4
- 239000011398 Portland cement Substances 0.000 claims description 3
- 239000004568 cement Substances 0.000 claims description 3
- 239000011083 cement mortar Substances 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000000843 powder Substances 0.000 claims description 3
- 238000007664 blowing Methods 0.000 claims description 2
- 230000003014 reinforcing effect Effects 0.000 abstract description 3
- 238000007569 slipcasting Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- 101100366060 Caenorhabditis elegans snap-29 gene Proteins 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000009510 drug design Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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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
- E21D11/04—Lining with building materials
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
-
- 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
- E21D11/04—Lining with building materials
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
- E21D11/105—Transport or application of concrete specially adapted for the lining of tunnels or galleries ; Backfilling the space between main building element and the surrounding rock, e.g. with concrete
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- Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Architecture (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Piles And Underground Anchors (AREA)
Abstract
The invention provides a soft rock roadway grouting reinforcement method, which comprises the following steps: in the extending direction of the roadway, setting a grouting hole drilling section at a set distance, and drilling a group of grouting holes in the circumferential direction of the grouting hole drilling section; and performing group-separated grouting on the grouting holes by taking the groups as units. According to the invention, the plurality of groups of grouting holes are arranged in the extending direction of the roadway, the function of improving the stability of the roadway is realized by grouting into the grouting holes, and the repairing and supporting cost of the roadway can be reduced. Meanwhile, in the process of grouting the grouting holes, the method of grouting at intervals is adopted, so that the grouting time of two adjacent groups of grouting holes has a certain interval, the grouting is favorably fully infiltrated, filled and solidified in soft rock hydrogeology of the roadway wall, and the reinforcing effect on the roadway is improved.
Description
Technical Field
The invention relates to the technical field of mining, in particular to a soft rock roadway grouting reinforcement method.
Background
The grouting process technology is mature at home and abroad at present, different grouting modes can be adopted according to different geological conditions and corresponding engineering requirements, but the core grouting process is the design of grouting holes, the selection of grouting materials and the design of grouting procedures. Under the condition of the hydrogeology of the Jurassic water-rich soft rock, the direct bottom of a coal bed mainly comprises sandy mudstone, carbonaceous mudstone and siltstone, the mud is cemented, part of the mud is sandy hard rock and contains water, the mud is a typical three-soft stratum, and is influenced by the stress of adjacent roadways, the bottom heave phenomenon is obvious after the roadway construction, frequent repair is needed, and the roadway support cost is increased.
Disclosure of Invention
Therefore, the invention aims to provide a soft rock roadway grouting reinforcement method which can reinforce a roadway under the hydrogeological condition of water-rich soft rock, increase the stability of the roadway and reduce the repair and support cost.
The invention provides a soft rock roadway grouting reinforcement method, which comprises the following steps:
step S1, setting a grouting hole drilling section at intervals of a set distance in the extending direction of the roadway, and drilling a group of grouting holes in the circumferential direction of the grouting hole drilling section;
and step S2, performing group-separated grouting on the grouting holes by taking the group as a unit.
According to the invention, the plurality of groups of grouting holes are arranged in the extending direction of the roadway, the function of improving the stability of the roadway is realized by grouting into the grouting holes, and the repairing and supporting cost of the roadway can be reduced. Meanwhile, in the process of grouting the grouting holes, the method of grouting at intervals is adopted, so that the grouting time of two adjacent groups of grouting holes has a certain interval, the grouting is favorably fully infiltrated, filled and solidified in soft rock hydrogeology of the roadway wall, and the reinforcing effect on the roadway is improved.
Further, the step 1 further comprises:
step S11, determining the distance between the drilling sections of two adjacent grouting holes as a, wherein the value range of a is 2000-4000 mm;
and step S12, determining the number b of a group of grouting holes, and determining the position distribution of each grouting hole, wherein the value range of b is 5-10.
Further, the step S12 is specifically: determining the number of a group of grouting holes to be 5, wherein 2 grouting holes are positioned at bottom corners on two sides of a roadway, 2 grouting holes are positioned at shoulders on two sides of the roadway, and 1 grouting hole is positioned at a vault of the roadway; wherein, the down-prick angle of the grouting holes at the bottom angles at the two sides is 30-45 degrees, and the included angle between the grouting holes at the shoulders and the arch top at the two sides and the profile surface of the roadway is not less than 75 degrees.
Further, the step S12 further includes: and (3) drilling grouting holes at the shoulders and the arch tops on two sides by using an anchor rope machine, drilling the grouting holes at the bottom corners on two sides by using an air drill, and completely blowing water and coal rock powder in the holes by using an eye cleaner.
Further, the step 2 further comprises:
step S21, installing a grouting pipe into the grouting hole;
step S22, sealing the grouting hole of the installed grouting pipe;
and step S23, after sealing for 24 hours, grouting the grouting holes through the grouting pipes.
Further, the step S21 further includes: the seamless steel pipe is selected to manufacture the grouting pipe, the caliber of the grouting pipe is matched with the caliber of the grouting hole, and the grouting pipe is provided with the grout outlets at intervals.
Further, the step S22 further includes: and (3) sealing the grouting hole by adopting cement mortar mixed with a quick-setting agent or sealing the grouting hole by adopting a quick-setting cement cartridge, wherein the sealing length is not less than 80mm, and the grouting pipe is exposed by 50-70 mm.
Further, the step S23 further includes: and (4) adopting an intermittent grouting method to perform grouting on the grouting holes in the sequence from bottom to top.
Furthermore, the intermittent time of the intermittent grouting method is controlled to be 10-20 minutes.
Further, the grouting material is ordinary portland cement single-liquid slurry, and the specific gravity of the slurry is 1.3-1.6 g/cm3The weight ratio of water to ash is 1: 1.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, 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 some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a flow chart of a soft rock roadway grouting reinforcement method.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. Furthermore, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The embodiment of the invention provides a soft rock roadway grouting reinforcement method, as shown in figure 1, comprising the following steps:
and step S1, setting a grouting hole drilling section at set intervals in the extending direction of the roadway, and drilling a group of grouting holes in the circumferential direction of the grouting hole drilling section.
And step S2, performing group-separated grouting on the grouting holes by taking the group as a unit.
According to the invention, the plurality of groups of grouting holes are arranged in the extending direction of the roadway, the function of improving the stability of the roadway is realized by grouting into the grouting holes, and the repairing and supporting cost of the roadway can be reduced. Meanwhile, in the process of grouting the grouting holes, the method of grouting at intervals is adopted, so that the grouting time of two adjacent groups of grouting holes has a certain interval, the grouting is favorably fully infiltrated, filled and solidified in soft rock hydrogeology of the roadway wall, and the reinforcing effect on the roadway is improved.
In an aspect of the embodiment of the present invention, the step 1 further includes:
and step S11, determining the distance between the drilling sections of two adjacent grouting holes as a, wherein the value range of a is 2000-4000 mm. Through the setting of the distance between the slip casting hole drilling section, the interblock interval in reasonable design slip casting hole when guaranteeing the reinforcement effect, cost is reduced as far as possible.
And step S12, determining the number b of a group of grouting holes, and determining the position distribution of each grouting hole, wherein the value range of b is 5-10. Through the quantity and the setting of position of a set of injected hole, the quantity and the distribution of rational design injected hole when guaranteeing to consolidate the effect, the cost is reduced as far as possible.
In a preferred embodiment, the number of a group of grouting holes is determined to be 5, wherein 2 are positioned at the bottom corners of two sides of the roadway, 2 are positioned at the shoulder parts of two sides of the roadway, and 1 is positioned at the top of the roadway; wherein, the down-prick angle of the grouting holes at the bottom angles at the two sides is 30-45 degrees, and the included angle between the grouting holes at the shoulders and the arch top at the two sides and the profile surface of the roadway is not less than 75 degrees. Preferably, the grouting holes at the shoulders and the arch tops on the two sides are drilled by an anchor cable machine, the grouting holes at the bottom corners on the two sides are drilled by an air drill, water and coal rock powder in the holes are completely blown out by an eye cleaner, and the aperture of the grouting holes is designed to be phi 28 mm. Specifically, the grouting holes at the bottom corners of the two sides are located 300mm above the roadway bottom plate, the depth of the grouting holes is set to 2000mm, and the group distance is set to 3000 mm.
In an aspect of the embodiment of the present invention, the step 2 further includes:
step S21, the grout pipe is installed into the grout hole. Preferably, a seamless steel pipe is selected to manufacture the grouting pipe, the caliber of the grouting pipe is matched with the caliber of the grouting hole, and the grouting pipe is provided with the grout outlets at intervals. In a specific embodiment, the grouting pipe is made of a seamless steel pipe with 22mm phi, the wall thickness of the steel pipe is 3mm, the length of the grouting pipe is 800mm, and slurry outlets with 6mm phi are spirally arranged on the body of the grouting pipe every 50 mm.
And step S22, sealing the grouting hole of the installed grouting pipe. Preferably, cement mortar is mixed with a quick-setting agent to seal a grouting hole, or a quick-setting cement roll is used to seal the grouting hole, the length of the seal is not less than 80mm, and the grouting pipe is exposed by 50-70 mm.
Step S23, sealing for 24 hoursAnd grouting the grouting holes through the grouting pipes. Preferably, an intermittent grouting method is adopted, grouting is carried out on the grouting holes in the sequence from bottom to top, and the intermittent time is controlled to be 10-20 minutes. In the embodiment of one group of 5 grouting holes, the grouting holes at the bottom feet of two sides are firstly grouted, then the grouting holes at the shoulder parts of two sides are grouted, and finally the grouting holes at the top plate are grouted, and meanwhile, the grouting holes are grouted in a group-separated grouting manner, for example, the grouting hole groups are numbered as 1, 2 and 3. Optionally, the grouting material is ordinary portland cement single-liquid slurry, and the specific gravity of the slurry is 1.3-1.6 g/cm3The weight ratio of water to ash is 1: 1.
The slip casting process is carried out to the slip casting pipe specifically and all adopts current slip casting equipment to go on, and concrete process is: before grouting, grouting equipment, a valve and a high-pressure grouting pipeline are connected and then grouting is started, when a pressure gauge reaches a design pressure value and the stabilization time reaches 15min, the grouting pump is closed, a stop ball valve at the position of a grouting pipe is closed, a pressure relief valve on the lower side of the pressure gauge is opened to relieve pressure, so that residual grout in the pipeline flows back into a liquid storage barrel, a U-shaped pin is detached, the grouting pipeline is taken down, and the grouting pipeline is mounted on the next grouting pipe to repeat the procedures to continue grouting.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. A soft rock roadway grouting reinforcement method is characterized by comprising the following steps:
step S1, setting a grouting hole drilling section at intervals of a set distance in the extending direction of the roadway, and drilling a group of grouting holes in the circumferential direction of the grouting hole drilling section;
and step S2, performing group-separated grouting on the grouting holes by taking the group as a unit.
2. The soft rock roadway grouting reinforcement method of claim 1, wherein the step 1 further comprises:
step S11, determining the distance between the drilling sections of two adjacent grouting holes as a, wherein the value range of a is 2000-4000 mm;
and step S12, determining the number b of a group of grouting holes, and determining the position distribution of each grouting hole, wherein the value range of b is 5-10.
3. The soft rock roadway grouting reinforcement method of claim 2, wherein the step S12 specifically comprises:
determining the number of a group of grouting holes to be 5, wherein 2 grouting holes are positioned at bottom corners on two sides of a roadway, 2 grouting holes are positioned at shoulders on two sides of the roadway, and 1 grouting hole is positioned at a vault of the roadway;
wherein, the down-prick angle of the grouting holes at the bottom angles at the two sides is 30-45 degrees, and the included angle between the grouting holes at the shoulders and the arch top at the two sides and the profile surface of the roadway is not less than 75 degrees.
4. The soft rock roadway grouting reinforcement method of claim 3, wherein the step S12 further comprises:
and (3) drilling grouting holes at the shoulders and the arch tops on two sides by using an anchor rope machine, drilling the grouting holes at the bottom corners on two sides by using an air drill, and completely blowing water and coal rock powder in the holes by using an eye cleaner.
5. The soft rock roadway grouting reinforcement method of claim 1, wherein the step 2 further comprises:
step S21, installing a grouting pipe into the grouting hole;
step S22, sealing the grouting hole of the installed grouting pipe;
and step S23, after sealing for 24 hours, grouting the grouting holes through the grouting pipes.
6. The soft rock roadway grouting reinforcement method of claim 5, wherein the step S21 further comprises:
the seamless steel pipe is selected to manufacture the grouting pipe, the caliber of the grouting pipe is matched with the caliber of the grouting hole, and the grouting pipe is provided with the grout outlets at intervals.
7. The soft rock roadway grouting reinforcement method of claim 5, wherein the step S22 further comprises:
and (3) sealing the grouting hole by adopting cement mortar mixed with a quick-setting agent or sealing the grouting hole by adopting a quick-setting cement cartridge, wherein the sealing length is not less than 80mm, and the grouting pipe is exposed by 50-70 mm.
8. The soft rock roadway grouting reinforcement method of claim 5, wherein the step S23 further comprises:
and (4) adopting an intermittent grouting method to perform grouting on the grouting holes in the sequence from bottom to top.
9. The soft rock roadway grouting reinforcement method of claim 8,
the intermittent time of the intermittent grouting method is controlled to be 10-20 minutes.
10. The soft rock roadway grouting reinforcement method of claim 9,
the grouting material is ordinary portland cement single-liquid slurry with the specific gravity of 1.3-1.6 g/cm3The weight ratio of water to ash is 1: 1.
Priority Applications (1)
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CN202011577858.6A CN112539073A (en) | 2020-12-28 | 2020-12-28 | Grouting reinforcement method for soft rock roadway |
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CN202011577858.6A CN112539073A (en) | 2020-12-28 | 2020-12-28 | Grouting reinforcement method for soft rock roadway |
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103089274A (en) * | 2013-01-15 | 2013-05-08 | 河南理工大学 | Method capable of repeated grouting and reinforcing surrounding rocks of roadway |
CN107083977A (en) * | 2017-06-23 | 2017-08-22 | 中国矿业大学 | A kind of grouting strengthening method of many granularities of argillaceous soft rock tunnel subregion |
CN206917672U (en) * | 2017-07-28 | 2018-01-23 | 河北钢铁集团矿业有限公司 | A kind of flood Mine Tunnel Construction Stage control water-bound |
CN109973120A (en) * | 2019-04-28 | 2019-07-05 | 中国矿业大学 | Two lane deformation control methods of drilling and joint slip casting are observed in a kind of reserved release |
CN110513129A (en) * | 2019-09-26 | 2019-11-29 | 黄祖军 | A kind of loose thick coal layer roadway workface fore-support supporting construction and method for protecting support |
-
2020
- 2020-12-28 CN CN202011577858.6A patent/CN112539073A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103089274A (en) * | 2013-01-15 | 2013-05-08 | 河南理工大学 | Method capable of repeated grouting and reinforcing surrounding rocks of roadway |
CN107083977A (en) * | 2017-06-23 | 2017-08-22 | 中国矿业大学 | A kind of grouting strengthening method of many granularities of argillaceous soft rock tunnel subregion |
CN206917672U (en) * | 2017-07-28 | 2018-01-23 | 河北钢铁集团矿业有限公司 | A kind of flood Mine Tunnel Construction Stage control water-bound |
CN109973120A (en) * | 2019-04-28 | 2019-07-05 | 中国矿业大学 | Two lane deformation control methods of drilling and joint slip casting are observed in a kind of reserved release |
CN110513129A (en) * | 2019-09-26 | 2019-11-29 | 黄祖军 | A kind of loose thick coal layer roadway workface fore-support supporting construction and method for protecting support |
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Application publication date: 20210323 |