CN112796769B - Construction method of water-rich weak surrounding rock stratum tunnel - Google Patents
Construction method of water-rich weak surrounding rock stratum tunnel Download PDFInfo
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- CN112796769B CN112796769B CN202011556267.0A CN202011556267A CN112796769B CN 112796769 B CN112796769 B CN 112796769B CN 202011556267 A CN202011556267 A CN 202011556267A CN 112796769 B CN112796769 B CN 112796769B
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 50
- 238000010276 construction Methods 0.000 title claims abstract description 37
- 239000011435 rock Substances 0.000 title claims abstract description 24
- 238000005553 drilling Methods 0.000 claims description 52
- 238000000034 method Methods 0.000 claims description 40
- 238000009412 basement excavation Methods 0.000 claims description 22
- 229910000831 Steel Inorganic materials 0.000 claims description 10
- 239000010959 steel Substances 0.000 claims description 10
- 239000004570 mortar (masonry) Substances 0.000 claims description 6
- 230000003014 reinforcing effect Effects 0.000 claims description 3
- 239000011378 shotcrete Substances 0.000 claims description 3
- 238000005192 partition Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005755 formation reaction Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000012876 topography Methods 0.000 description 1
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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
- E21D9/04—Driving tunnels or galleries through loose materials; Apparatus therefor not otherwise provided for
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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
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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
- E21D11/14—Lining predominantly with metal
- E21D11/18—Arch members ; Network made of arch members ; Ring elements; Polygon elements; Polygon elements inside arches
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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
- E21D11/14—Lining predominantly with metal
- E21D11/18—Arch members ; Network made of arch members ; Ring elements; Polygon elements; Polygon elements inside arches
- E21D11/183—Supporting means for arch members, not provided for in E21D11/22
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F16/00—Drainage
- E21F16/02—Drainage of tunnels
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Architecture (AREA)
- Structural Engineering (AREA)
- Civil Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Lining And Supports For Tunnels (AREA)
Abstract
The invention discloses a construction method of a water-rich weak surrounding rock stratum tunnel, which comprises the following steps: firstly, primary digging; step two, excavating an upper step; step three, arranging a small upper-step guide pipe; step four, finishing upper support; step five, excavating a lower step; step six, arranging a small lower step catheter; step seven, finishing lower support; and step eight, excavating an inverted arch part. The invention combines drainage and reinforced tunnel support into a whole, has simple drainage operation, improves the construction efficiency and shortens the construction progress.
Description
Technical Field
The invention relates to the technical field of tunnel engineering, in particular to a construction method of a water-rich weak surrounding rock stratum tunnel.
Background
In recent years, with the deep advancement of tunnel construction, it is still normal to construct tunnels in complex areas. However, the system is limited by a plurality of factors such as planning design and use requirements, topography and geological conditions and the like, so that higher requirements are put on the safe construction of tunnels.
In the process of constructing a tunnel, the construction methods such as a full-section face excavation method, a step method, a middle partition wall method, a cross middle partition wall method and the like are mainly adopted at present. In the construction of tunnels in western mountainous areas, water-rich weak formations are common. At present, a construction method such as a step method is often adopted in a water-rich weak stratum, but drainage operation combined with the construction method is complex, construction progress is seriously dragged and slowed down, construction efficiency is reduced, and a construction method which is suitable for a water-rich weak surrounding rock stratum tunnel and combines drainage and reinforced tunnel support into a whole is not available.
Disclosure of Invention
The invention aims to provide a construction method of a water-rich weak surrounding rock stratum tunnel, which combines drainage and reinforced tunnel support into a whole, reduces construction cost, ensures construction safety, has simple drainage operation, improves construction efficiency and shortens construction progress.
In order to achieve the above purpose, the construction method of the water-rich weak surrounding rock stratum tunnel provided by the invention comprises the following steps:
firstly, excavating to a water-rich weak surrounding rock section by adopting a step method;
step two, excavating an upper step, quickly applying sprayed concrete, and performing advanced drilling on arch feet designed on two sides of an excavated surface by utilizing a drilling machine;
step three, arranging small guide pipes with upper steps, conveying the small guide pipes into the drill holes in the step two, grouting the small guide pipes, condensing mortar and surrounding rock of each small guide pipe to form a stable structure, and forming first large arch feet on two sides of an excavation surface;
step four, completing upper support, namely erecting a steel frame and a first foot locking anchor pipe by utilizing the first large arch foot formed in the step three to form a complete upper support system;
fifthly, excavating a lower step, and performing advanced drilling on arch springing positions designed on two sides of the lower step by using a drilling machine to perform advanced geological forecast;
step six, arranging lower-step small guide pipes, conveying the small guide pipes into the drill holes in the step five, grouting the small guide pipes, condensing mortar and surrounding rock of each small guide pipe to form a stable structure, and forming second large arch feet on two sides of the lower step;
step seven, completing the lower support, and using the second large arch leg formed in the step six to select and erect a steel frame, a second lock leg anchor pipe and a reinforcing mesh for construction to form a complete lower support system;
and step eight, excavating an inverted arch part, and applying inverted arch support and backfilling the inverted arch by utilizing the second large arch foot formed in the step six.
Preferably, the advanced drilling in the second step has the following three cases:
A. if the two ends meet underground water in the advanced drilling process, firstly performing drainage operation through drilling, draining the front underground water, and then excavating;
B. if the two ends of the advanced drilling process do not meet underground water, normal excavation operation is carried out;
C. if one side meets underground water in the advanced drilling process, the side firstly drains the front underground water through drilling, then excavates, and the other side performs advanced excavation operation.
Preferably, the advanced drilling in the fifth step has the following three cases:
A. if the two ends meet underground water in the advanced drilling process, firstly performing drainage operation through drilling, draining the front underground water, and then excavating;
B. if the two ends of the advanced drilling process do not meet underground water, normal excavation operation is carried out;
C. if one side meets underground water in the advanced drilling process, the side firstly drains the front underground water through drilling, then excavates, and the other side performs advanced excavation operation.
Preferably, the step method in the first step is a two-step method.
Preferably, the step method in the first step is a three-step seven-step excavation method.
Preferably, the diameter of the bore is greater than the diameter of the small conduit.
Preferably, the difference between the diameter of the drilled hole and the diameter of the small conduit is 0-50mm.
Preferably, the first large arch leg and the second large arch leg comprise supporting components and backing plates, one end of each supporting component is connected with each backing plate, and the other end of each supporting component is connected with the side wall of the tunnel.
Further, the support component is I-steel.
Compared with the prior art, the invention has the following technical effects:
1. the invention combines drainage and reinforced tunnel support into a whole;
2. the invention can reduce construction cost and ensure construction safety;
3. the drainage method is simple in drainage operation, improves construction efficiency and shortens construction progress.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered limiting the scope, and that other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic view of the overall structure of a face according to an embodiment;
FIG. 2 is a schematic diagram of a position of advanced drilling in an embodiment;
icon: 1-design rail surface, 2-drilling, 3-first big arch springing, 4-second big arch springing, 5-first locking anchor pipe, 6-second locking anchor pipe, 7-inverted arch, 8-supporting component and 9-backing plate.
Detailed Description
For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, which are 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 present application, as provided in the accompanying drawings, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.
It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other.
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 embodiments of the present application, it should be noted that, the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is conventionally put when the product of the application is used, or the orientation or positional relationship that is conventionally understood by those skilled in the art, or the orientation or positional relationship that is conventionally put when the product of the application is used, which is merely for convenience of describing the application and simplifying the description, and is not indicative or implying that the device or element to be referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the application. 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.
In the description of the embodiments of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be directly connected or indirectly connected through an intermediate medium. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.
Examples
A construction method of a water-rich weak surrounding rock stratum tunnel comprises the following steps:
firstly, excavating initially, constructing according to a design drawing, and excavating to a water-rich weak surrounding rock section by adopting a step method;
step two, excavating an upper step, quickly applying sprayed concrete, and performing advanced drilling on arch feet designed on two sides of an excavated surface by utilizing a drilling machine;
step three, arranging small guide pipes with upper steps, conveying the small guide pipes into the drill holes in the step two, grouting the small guide pipes, condensing mortar and surrounding rock of each small guide pipe to form a stable structure, and forming first large arch feet on two sides of an excavation surface;
step four, completing upper support, namely erecting a steel frame and a first foot locking anchor pipe by utilizing the first large arch foot formed in the step three to form a complete upper support system;
fifthly, excavating a lower step, and performing advanced drilling on arch springing positions designed on two sides of the lower step by using a drilling machine to perform advanced geological forecast;
step six, arranging lower-step small guide pipes, conveying the small guide pipes into the drill holes in the step five, grouting the small guide pipes, condensing mortar and surrounding rock of each small guide pipe to form a stable structure, and forming second large arch feet on two sides of the lower step;
step seven, completing the lower support, and using the second large arch leg formed in the step six to select and erect a steel frame, a second lock leg anchor pipe and a reinforcing mesh for construction to form a complete lower support system;
and step eight, excavating an inverted arch part, and applying inverted arch support and backfilling the inverted arch by utilizing the second large arch foot formed in the step six.
The advanced drilling in the second step has the following three conditions:
A. if the two ends meet underground water in the advanced drilling process, firstly performing drainage operation through drilling, draining the front underground water, and then excavating;
B. if the two ends of the advanced drilling process do not meet underground water, normal excavation operation is carried out;
C. if one side meets underground water in the advanced drilling process, the side firstly drains the front underground water through drilling, then excavates, and the other side performs advanced excavation operation.
The advanced drilling in the fifth step has the following three conditions:
A. if the two ends meet underground water in the advanced drilling process, firstly performing drainage operation through drilling, draining the front underground water, and then excavating;
B. if the two ends of the advanced drilling process do not meet underground water, normal excavation operation is carried out;
C. if one side meets underground water in the advanced drilling process, the side firstly drains the front underground water through drilling, then excavates, and the other side performs advanced excavation operation.
The drilling direction is parallel to the tunnel excavation direction.
The diameter of the borehole is larger than the diameter of the small conduit.
The difference between the diameter of the drilled hole and the diameter of the small guide pipe is 0-50mm.
The first large arch leg and the second large arch leg comprise supporting components and backing plates, one end of each supporting component is connected with each backing plate, and the other end of each supporting component is connected with the side wall of the tunnel.
The support assembly is I-steel, and the backing plate is made of metal material, usually steel material.
Example 1
The step method in the first step is a two-step method.
Example two
The step method in the first step is a three-step seven-step excavation method.
Of course, the present invention is capable of other various embodiments and its several details are capable of modification and variation in light of the present invention by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (7)
1. The construction method of the water-rich weak surrounding rock stratum tunnel is characterized by comprising the following steps of:
firstly, excavating to a water-rich weak surrounding rock section by adopting a step method;
step two, excavating an upper step, quickly applying sprayed concrete, and performing advanced drilling on arch feet designed on two sides of an excavated surface by utilizing a drilling machine, wherein the drilling direction is parallel to the tunnel excavation direction;
step three, arranging small guide pipes with upper steps, conveying the small guide pipes into the drill holes in the step two, grouting the small guide pipes, condensing mortar and surrounding rock of each small guide pipe to form a stable structure, and forming first large arch feet on two sides of an excavation surface;
step four, completing upper support, namely erecting a steel frame and a first foot locking anchor pipe by utilizing the first large arch foot formed in the step three to form a complete upper support system;
fifthly, excavating a lower step, and performing advanced drilling on arch springing positions designed on two sides of the lower step by using a drilling machine to perform advanced geological forecast;
step six, arranging lower-step small guide pipes, conveying the small guide pipes into the drill holes in the step five, grouting the small guide pipes, condensing mortar and surrounding rock of each small guide pipe to form a stable structure, and forming second large arch feet on two sides of the lower step;
step seven, completing the lower support, and using the second large arch leg formed in the step six to select and erect a steel frame, a second lock leg anchor pipe and a reinforcing mesh for construction to form a complete lower support system;
excavating an inverted arch part, and using the second large arch foot formed in the step six to apply inverted arch support and backfill the inverted arch;
the advanced drilling in the second step has the following three conditions:
A. if the two ends meet underground water in the advanced drilling process, firstly performing drainage operation through drilling, draining the front underground water, and then excavating;
B. if the two ends of the advanced drilling process do not meet underground water, normal excavation operation is carried out;
C. if one side meets underground water in the advanced drilling process, the side firstly performs drainage operation through drilling, drains the front underground water, performs excavation, and performs advanced excavation operation on the other side;
the advanced drilling in the fifth step has the following three conditions:
A. if the two ends meet underground water in the advanced drilling process, firstly performing drainage operation through drilling, draining the front underground water, and then excavating;
B. if the two ends of the advanced drilling process do not meet underground water, normal excavation operation is carried out;
C. if one side meets underground water in the advanced drilling process, the side firstly drains the front underground water through drilling, then excavates, and the other side performs advanced excavation operation.
2. The construction method of the water-rich weak surrounding rock stratum tunnel according to claim 1, which is characterized by comprising the following steps: the step method in the first step is a two-step method.
3. The construction method of the water-rich weak surrounding rock stratum tunnel according to claim 1, which is characterized by comprising the following steps: the step method in the first step is a three-step seven-step excavation method.
4. The construction method of the water-rich weak surrounding rock stratum tunnel according to claim 1, which is characterized by comprising the following steps: the diameter of the bore is greater than the diameter of the small conduit.
5. The construction method of the water-rich weak surrounding rock stratum tunnel according to claim 4, which is characterized in that: the difference between the diameter of the drilled hole and the diameter of the small guide pipe is 0-50mm.
6. The construction method of the water-rich weak surrounding rock stratum tunnel according to claim 1, which is characterized by comprising the following steps: the first large arch leg and the second large arch leg comprise supporting components and backing plates, one end of each supporting component is connected with each backing plate, and the other end of each supporting component is connected with the side wall of the tunnel.
7. The construction method of the water-rich weak surrounding rock stratum tunnel according to claim 6, wherein the construction method comprises the following steps: the support component is I-steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202011556267.0A CN112796769B (en) | 2020-12-24 | 2020-12-24 | Construction method of water-rich weak surrounding rock stratum tunnel |
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| CN202011556267.0A CN112796769B (en) | 2020-12-24 | 2020-12-24 | Construction method of water-rich weak surrounding rock stratum tunnel |
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| CN112796769B true CN112796769B (en) | 2023-05-05 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101761346B (en) * | 2009-12-30 | 2012-10-03 | 中铁十二局集团第二工程有限公司 | Method for constructing metamorphic rock confined water tunnel |
| CN103334770B (en) * | 2013-06-09 | 2015-08-12 | 中铁隧道集团有限公司 | One is grown up reverse-slope tunnel ultra high water pressure rich water zone of fracture construction method |
| CN108278115A (en) * | 2017-10-31 | 2018-07-13 | 中南大学 | A kind of three step Rapid Construction of Tunnels method of big arch springing and structure based on pre-timbering with tubular prop |
| CN108798702B (en) * | 2018-06-05 | 2020-04-28 | 长安大学 | Supporting method for large-section soft rock large-deformation tunnel |
| CN110630285A (en) * | 2019-10-08 | 2019-12-31 | 甘肃恒路交通勘察设计院有限公司 | Anchor cable-steel frame support and construction method for large-section soft rock tunnel |
| CN111206933A (en) * | 2020-01-20 | 2020-05-29 | 西南交通大学 | A tunnel construction method for crossing karst water-rich section |
| CN111734450B (en) * | 2020-06-30 | 2022-03-08 | 高军 | Safe and rapid tunneling and supporting method for water-rich fault zone tunnel |
| CN111764932B (en) * | 2020-07-06 | 2021-11-02 | 高军 | Low-risk construction method for muddy water-rich broken shallow tunnel |
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