CN112727474B - A feather-shaped directional soft rock tunnel advance grouting pre-reinforcement structure and method - Google Patents
A feather-shaped directional soft rock tunnel advance grouting pre-reinforcement structure and method Download PDFInfo
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- CN112727474B CN112727474B CN202110186622.8A CN202110186622A CN112727474B CN 112727474 B CN112727474 B CN 112727474B CN 202110186622 A CN202110186622 A CN 202110186622A CN 112727474 B CN112727474 B CN 112727474B
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- grouting
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- drill bit
- drilling
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- 239000011435 rock Substances 0.000 title claims abstract description 31
- 230000002787 reinforcement Effects 0.000 title claims abstract description 25
- 238000000034 method Methods 0.000 title claims abstract description 22
- 238000005553 drilling Methods 0.000 claims abstract description 87
- 238000010276 construction Methods 0.000 claims abstract description 16
- 230000004323 axial length Effects 0.000 claims abstract description 6
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 3
- 239000010959 steel Substances 0.000 claims abstract description 3
- 239000002002 slurry Substances 0.000 claims description 5
- 238000009412 basement excavation Methods 0.000 claims description 4
- 239000004568 cement Substances 0.000 claims description 4
- 210000003746 feather Anatomy 0.000 claims description 2
- 239000011440 grout Substances 0.000 claims 2
- 230000015572 biosynthetic process Effects 0.000 claims 1
- 230000001681 protective effect Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 5
- 238000005192 partition Methods 0.000 description 4
- 230000003014 reinforcing effect Effects 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 239000004927 clay Substances 0.000 description 1
- 230000009189 diving Effects 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/001—Improving soil or rock, e.g. by freezing; Injections
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/20—Flexible or articulated drilling pipes, e.g. flexible or articulated rods, pipes or cables
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/20—Flexible or articulated drilling pipes, e.g. flexible or articulated rods, pipes or cables
- E21B17/206—Flexible or articulated drilling pipes, e.g. flexible or articulated rods, pipes or cables with conductors, e.g. electrical, optical
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/04—Driving tunnels or galleries through loose materials; Apparatus therefor not otherwise provided for
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- Soil Sciences (AREA)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
一种羽状定向软岩隧道超前注浆预加固结构和方法，属于地下工程与岩土工程施工领域。加固结构，包括羽状定向注浆钻孔(1)、柔性钻具(2)、定向钻头(3)、钻头导向控制器(4)；其中，羽状定向注浆钻孔(1)包括中心钻孔和向四周分散的多个分支钻孔，中心钻孔为钻机预打与隧道轴长方向一致的长钻孔，在长钻孔内下入保护井壁的钢护筒，分支钻孔为从中心钻孔向四周延伸出多个弯曲的指向隧道(6)内壁的钻孔，分支钻孔在中心钻孔的周向为2‑6个，且分支钻孔沿中心钻孔的轴长方向均匀分布，中心钻孔和分支钻孔整体结构呈羽毛状结构；向分支钻孔内注浆形成加固结构。
A feather-shaped directional soft rock tunnel advance grouting pre-reinforcement structure and method, belonging to the field of underground engineering and geotechnical engineering construction. The reinforcement structure comprises a feather-shaped directional grouting borehole (1), a flexible drilling tool (2), a directional drill bit (3), and a drill bit guide controller (4); wherein the feather-shaped directional grouting borehole (1) comprises a central borehole and a plurality of branch boreholes dispersed in all directions, the central borehole is a long borehole pre-drilled by a drilling rig in the same direction as the axial length of the tunnel, a steel casing for protecting the well wall is inserted into the long borehole, and the branch boreholes are a plurality of curved boreholes extending from the central borehole to the surroundings and pointing to the inner wall of the tunnel (6), the number of branch boreholes in the circumferential direction of the central borehole is 2-6, and the branch boreholes are evenly distributed along the axial length direction of the central borehole, and the overall structure of the central borehole and the branch boreholes is a feather-shaped structure; grouting is injected into the branch boreholes to form the reinforcement structure.
Description
Technical Field
The invention relates to a pinnate directional soft rock tunnel advanced grouting pre-reinforcement method, and belongs to the field of underground engineering and geotechnical engineering construction methods.
Background
For soft rock tunnels, due to low surrounding rock strength and poor self-stabilization capability, construction risks such as collapse, large deformation and the like are easy to generate, and construction quality problems, a grouting reinforcement method is usually adopted to perform full-section grouting pre-reinforcement treatment on surrounding rock in front of a tunnel face before tunnel excavation, grouting holes are arranged in a quincuncial shape on the tunnel face, and cement slurry is injected into the holes to reinforce the surrounding rock in front. However, because the tunnel face space is limited, construction equipment is difficult to position, great difficulty is brought to construction, a large number of grouting holes are required to be constructed, engineering quantity waste and material waste are caused, and economic benefit is poor.
The invention relates to an advanced grouting pre-reinforcing method for a pinnate directional soft rock tunnel, which is used for constructing a small amount of drilling holes, carrying out pinnate directional pore-forming and directional grouting, carrying out full-section grouting pre-reinforcing on surrounding rocks in front of a tunnel face, effectively controlling construction risk and improving engineering quality.
Disclosure of Invention
The invention discloses an advanced grouting pre-reinforcement method of a pinnate directional soft rock tunnel, which is a full-section grouting reinforcement structure of the soft rock tunnel, and comprises pinnate directional grouting drilling holes (1), flexible drilling tools (2), directional drilling bits (3) and a drill bit guiding controller (4), wherein the pinnate directional grouting drilling holes (1) comprise central drilling holes and a plurality of branch drilling holes which are dispersed to the periphery, the central drilling holes are long drilling holes which are consistent with the axial length direction of the tunnel, a steel casing for protecting a well wall is arranged in the long drilling holes in a descending manner, the branch drilling holes are drilling holes which extend from the central drilling holes to the periphery and are bent and are directed to the inner wall of the tunnel (6), the number of the branch drilling holes is 2-6 in the circumferential direction of the central drilling holes, the branch drilling holes are uniformly distributed along the axial length direction of the central drilling holes, and the overall structure of the central drilling holes and the branch drilling holes is in a feather structure;
The flexible drilling tool (2) comprises a connecting screw thread (2.1), a connecting body (2.2), lugs (2.3), pins/holes (2.4) and an outer wall rubber high-pressure protection structure (2.5), wherein one end of the connecting body (2.2) is the connecting screw thread (2.1), the other end of the connecting body is the lugs (2.3), the lugs (2.3) are provided with the pins/holes (2.4), the connecting parts are connected with the connecting screw thread (2.1) and the lugs (2.3) in an end-to-end mode, the pins/holes (2.4) are used for fixing, a flexible long connecting body is formed, the periphery of the flexible long connecting body is the outer wall rubber high-pressure protection structure (2.5), one end of the flexible long connecting body extends into a drill hole and is used for grouting, the other end of the flexible long connecting body is positioned outside the drill hole and is used for being connected with a grouting pump, and one end part extending into the drill hole is a directional drill bit (3);
The connecting body (2.2) is arranged in the flexible drilling tool and is a main body part of the drilling tool and plays a role in transmitting pressure and torque;
The pin/hole (2.4) is arranged in the flexible drilling tool and is a main body part of the drilling tool, and is connected with and fixedly connected with the connecting body (2.2);
The outer wall rubber high-pressure protection structure (2.5) is characterized in that the drilling tool connector is limited, circulating slurry and cement slurry are injected, and the pressure-resistant grade is higher than the grouting pressure;
The directional drill (3) comprises a drill body and a drill guiding controller (4), wherein the drill guiding controller (4) is fixed on the drill body, the ground control system controls the guide (4), and the position of the drill is measured and the drilling direction of the drill is controlled;
The diameter of the drilling hole is larger than the outer diameter of the drilling hole casing;
The outer diameter of the casing is larger than that of the pilot bit (3);
The method is suitable for pre-reinforcing surrounding rock (8) in front of the tunnel face (7) in the soft rock (8) tunnel (6).
The invention discloses a pinnate directional soft rock tunnel advanced grouting pre-reinforcement method, which is a soft rock tunnel full-section grouting reinforcement method and comprises the following steps:
Firstly, on-site lofting to determine the position of a grouting hole, and installing horizontal drilling equipment;
secondly, constructing a horizontal drilling hole to the depth of a grouting area (A) by adopting a horizontal directional drilling machine, namely, driving a pile casing in the area A of the initial end area of the central drilling hole;
Thirdly, a flexible drilling tool (2) and a directional drilling bit (3) are put into a to-be-drilled hole, the drilling direction is controlled by a drill bit guiding controller (4) to be deflected along the track direction and the position of a grouting hole of a designed branch drilling hole, and a first branch drilling hole is prepared; the method comprises the steps of connecting a grouting pump at the other end part of a drilling tool flexibly, pumping cement slurry through the flexible drilling tool, performing high-pressure rotary jetting grouting on a first section (A-1) of the end part of the drilling head at the end part of a first branch drilling hole, stopping after the grouting time is reached under the designed grouting pressure, backing the drilling tool, stopping after the drilling head reaches a second grouting section (A-2), performing high-pressure rotary jetting grouting, stopping after the grouting time is reached under the designed grouting pressure, and so on to complete all inclined hole grouting work in the first branch drilling hole;
continuously constructing horizontal drilling holes to the depth of a first grouting area (B), namely, continuously driving a pile casing into the front area of a central drilling hole starting end area A, and sequentially preparing all branch drilling holes in the grouting area (B) and performing all inclined hole grouting according to the third step;
And step five, and so on, continuously constructing horizontal drilling holes to different areas in the front of the grouting area (B) according to the step four, continuously driving a pile casing, and respectively carrying out preparation and all inclined hole grouting work on all branch drilling holes in each area until all the branch drilling holes corresponding to the whole central drilling hole are completely grouted.
Step five, the analogy is carried out, horizontal drilling is continuously carried out to each area in front of the grouting area (B) according to the step four, the grouting area is generally divided into A, B, C, D and the grouting area from near to far, the size division of the areas and the grouting area is determined according to the design requirement, and the grouting sequence is carried out from near to far;
In the third step, each branch drilling hole is divided into sections A-1, A-2, A-3, and the like from far to near according to the distance from the center drilling hole, the size of the grouting section is determined according to the stratum property and the grouting equipment capacity, and the grouting sequence is carried out from far to near;
the first step, the central drilling hole is arranged in the middle of the tunnel face, the grouting position is fully distributed in a feathered mode according to the full section of tunnel excavation, and the track direction of the grouting hole is controlled by a ground control system to conduct deflecting construction by a guide controller (4);
the deflecting directions of grouting holes in the same grouting area can be crossed and sequentially performed in different directions;
The invention can also be used for vertical directional grouting;
The present invention includes, but is not limited to, the above.
The invention has the advantages that:
the pre-grouting pre-reinforcement method for the pinnate directional soft rock tunnel has the following advantages:
(1) Fully utilizing limited ground space, constructing the least grouting holes, and carrying out full-section grouting pre-reinforcement on surrounding rocks in front of tunnel face surfaces;
(2) According to the invention, the flexible drilling tool and the directional drilling bit are adopted, the direction and the position of the grouting hole can be controlled through the ground control system, and the tunnel surrounding rock can be precisely positioned and grouting at any position can be performed;
(3) The invention is suitable for directional grouting in any direction and directional grouting along a layer surface;
(4) The invention realizes positioning and directional grouting, can save a great amount of grouting materials and construction workload, effectively improves economic benefit and social benefit, and realizes green construction.
(5) The invention has theoretical value and application value, and has replicability and generalizability.
Drawings
FIG. 1 is a schematic diagram of pre-grouting and pre-reinforcing of a tunnel face feathered directional soft rock tunnel;
FIG. 2 is a schematic diagram of directional grouting partition and construction sequence of surrounding rock of a tunnel face;
FIG. 3 is a schematic diagram of directional grouting segments of surrounding rock of a tunnel face;
FIG. 4 is a tunnel face structure diagram;
FIG. 5 is a diagram of a flexible drilling tool and drill bit relationship;
Wherein:
1. feathered directional grouting drilling;
2. 2.1 connecting screw threads, 2.2 connecting bodies, 2.3 lugs and 2.4 pins/holes;
3. Directional drill bit
4. Drill bit guiding controller
5. Grouting partition
6. Tunnel
7. Face of hand
8. Surrounding rock.
Detailed Description
The present invention will be further described with reference to the following example of a subway tunnel in Beijing, but the present invention is not limited to the following example.
The underground of a certain Beijing subway tunnel is 0-15 m in the form of a powder clay and sand layer, the underground water is rich, the underground water type is in a diving-bearing water mixed mode, the section of the subway tunnel is about 100m 2, and the tunnel construction method is a CRD method. When the tunnel (6) is constructed to the face (7) in the soft rock stratum (8), grouting pre-reinforcement is carried out on surrounding rock in front of the face.
The first step of the invention is that a drilling machine is in place, construction lofting is carried out according to a tunnel design drawing, the position of a grouting hole is determined, and the drilling position is basically arranged at the center of a tunnel face of a tunnel;
secondly, grouting hole construction is carried out by adopting a horizontal drilling machine, and the grouting hole construction is firstly carried out to an A grouting area according to the designed grouting partition position;
thirdly, directionally controlling the drill bit in a ground control chamber, controlling the position and the direction of a drill bit guiding controller (4), directionally deflecting and drilling holes along the grouting direction of the designed branch drilling holes by using a flexible drilling tool and a directional drill bit, and flushing the drilling holes to the position of the section A-1 of the grouting area A of the tunnel face;
Fourthly, installing a flange plate at the orifice, connecting a grouting pump, and grouting the section A-1 of the grouting area of the tunnel face by using a flexible drilling tool and a drill bit at a high pressure, wherein the grouting pressure is about 0.5, and the stable grouting time is about 1 hour;
fifthly, backing the drilling tool by about 0.5 meter, carrying out high-pressure grouting on the section A-2 of the grouting area of the tunnel face, wherein the grouting pressure is about 0.5, and the stable grouting time is about 1 hour;
sequentially backing back the drilling tool, and carrying out high-pressure grouting on each grouting direction and each grouting section of the grouting area A by about 0.5 meter each time, wherein each grouting direction is crossed and sequentially carried out, so as to finish grouting reinforcement of the grouting area A of the tunnel face;
seventh, according to the grouting partition (5) of the tunnel, continuing to construct grouting holes to the grouting area B along the horizontal drilling holes, continuing to drive the pile casing (1), and repeating the third to sixth steps to finish grouting reinforcement of each grouting direction and each grouting section of the grouting area B;
Eighth, continuing to construct grouting holes to a grouting area C along the horizontal drilling, continuously driving a pile casing (1), and repeating the third step to the sixth step to sequentially finish grouting reinforcement of grouting directions and grouting sections of grouting areas C, D, E, F and the like;
and the grouting of all the designed sections is gradually constructed and completed, so that a surrounding rock reinforcement area in front of the tunnel face is formed, and then the excavation work of the tunnel face is carried out.
The pre-grouting pre-reinforcement method for the pinnate directional soft rock tunnel comprises the steps, is not limited to the steps, and is also suitable for related methods of directional grouting of vertical equal-drilling holes.
Claims (6)
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110186622.8A CN112727474B (en) | 2021-02-10 | 2021-02-10 | A feather-shaped directional soft rock tunnel advance grouting pre-reinforcement structure and method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110186622.8A CN112727474B (en) | 2021-02-10 | 2021-02-10 | A feather-shaped directional soft rock tunnel advance grouting pre-reinforcement structure and method |
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| Publication Number | Publication Date |
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| CN112727474A CN112727474A (en) | 2021-04-30 |
| CN112727474B true CN112727474B (en) | 2024-12-13 |
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| CN118223800B (en) * | 2024-05-24 | 2024-07-19 | 西安石油大学 | Bionic flexible drill rod with ultra-short radius |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101078335A (en) * | 2007-06-28 | 2007-11-28 | 北京万维亿通科技发展有限公司 | Ultra-short radius radial horizontal well drilling, completion tool and technique thereof |
| CN109899089A (en) * | 2019-03-07 | 2019-06-18 | 中煤科工集团西安研究院有限公司 | Goaf grouting method based on pinniform horizontal branch directional drilling technique |
| CN215718753U (en) * | 2021-02-10 | 2022-02-01 | 北京市政路桥股份有限公司 | An advanced grouting pre-reinforcement structure for a feather-shaped directional soft rock tunnel |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6923273B2 (en) * | 1997-10-27 | 2005-08-02 | Halliburton Energy Services, Inc. | Well system |
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- 2021-02-10 CN CN202110186622.8A patent/CN112727474B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101078335A (en) * | 2007-06-28 | 2007-11-28 | 北京万维亿通科技发展有限公司 | Ultra-short radius radial horizontal well drilling, completion tool and technique thereof |
| CN109899089A (en) * | 2019-03-07 | 2019-06-18 | 中煤科工集团西安研究院有限公司 | Goaf grouting method based on pinniform horizontal branch directional drilling technique |
| CN215718753U (en) * | 2021-02-10 | 2022-02-01 | 北京市政路桥股份有限公司 | An advanced grouting pre-reinforcement structure for a feather-shaped directional soft rock tunnel |
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