CN115163084A - Mechanical construction method for ultra-large section tunnel by double-side-wall pit guiding method - Google Patents
Mechanical construction method for ultra-large section tunnel by double-side-wall pit guiding method Download PDFInfo
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- CN115163084A CN115163084A CN202210869017.5A CN202210869017A CN115163084A CN 115163084 A CN115163084 A CN 115163084A CN 202210869017 A CN202210869017 A CN 202210869017A CN 115163084 A CN115163084 A CN 115163084A
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21D11/003—Linings or provisions thereon, specially adapted for traffic tunnels, e.g. with built-in cleaning devices
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21D11/006—Lining anchored in the rock
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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 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
- E21D11/107—Reinforcing elements therefor; Holders for the reinforcing elements
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21D11/20—Special cross- sections, e.g. corrugated
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- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21D9/006—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries by making use of blasting methods
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH 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
- E21D9/10—Making by using boring or cutting machines
Abstract
The invention discloses a mechanized construction method of a double-side-wall pit guiding method of an oversized cross-section tunnel, which comprises the following steps: s1, excavating rock masses of pilot tunnels on the left side and the right side; s2, adopting an advanced middle pipe shed support and an advanced small pipe support inside the tunnel body; s3, excavating rock masses of the left and right middle pilot tunnels; s4, excavating a rock mass of the middle pilot tunnel in the middle position; s5, excavating a rock mass located in a lower guide pit; s6, forming an upper layer structure, a middle layer structure and a lower layer structure in the tunnel, simultaneously drilling holes in the upper step, the middle step and the lower step by adopting a three-arm drill jumbo, firstly blasting the upper step during blasting, deslagging to support sprayed concrete, then blasting the middle step and the lower step, and deslagging to support the sprayed concrete. Based on two vertical temporary supports, cancel interim stull, the tunnel divide into the three-layer excavation, disposes two three-arm drill jumbo drilling, under the prerequisite of guaranteeing tunnel country rock safety and stability, very big improvement tunnel excavation work efficiency, and can furthest's performance mechanized efficiency of construction, effectively shortened construction period.
Description
Technical Field
The invention relates to the technical field of tunnel construction, in particular to a mechanized construction method of a double-side-wall pit guiding method for a tunnel with an ultra-large section.
Background
The existing bidirectional eight-lane highway tunnel is usually designed to have an ultra-large section, and in the process of constructing the ultra-large section tunnel, the supporting structure is more complicated in stress and the construction method is more diversified; the existing excavation support method mainly adopts a double-side-wall pit guiding method, but is limited by the size of a plurality of temporary supporting structures, and the excavation height of a single tunnel face of a tunnel is limited; the construction of large-scale machinery can not be adopted, the working procedures are crossed more, the construction progress is slow, the number of temporary supports is large, the deformation of surrounding rocks is large when the temporary supports are removed, the safety risk is high, the mechanical construction efficiency is limited, the working efficiency of tunnel excavation can not be improved, and the purpose of ensuring safe and rapid tunnel communication can not be achieved.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a mechanized construction method of a double-side-wall pit guiding method for a tunnel with an oversized section, which can effectively improve the tunnel excavation work efficiency and shorten the construction period.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the mechanized construction method of the double-side-wall pit guiding method for the tunnel with the oversized section comprises the following steps:
s1, excavating rock masses of upper pilot tunnels on the left side and the right side;
s2, adopting an advanced middle pipe shed support and an advanced small pipe support inside the tunnel body;
s3, excavating rock masses of the left and right middle pilot tunnels;
s4, excavating a rock mass of the middle pilot tunnel in the middle position;
s5, excavating a rock mass located in a lower guide pit;
s6, forming an upper layer structure, a middle layer structure and a lower layer structure in the tunnel, simultaneously drilling holes in the upper step, the middle step and the lower step by adopting a three-arm drill jumbo, firstly blasting the upper step during blasting, deslagging to support sprayed concrete, then blasting the middle step and the lower step, and deslagging to support the sprayed concrete.
Wherein the content of the first and second substances,
two vertical temporary supports are arranged in the tunnel to form two side pilot holes and a middle pilot hole.
And before the step S1, advanced geological prediction is carried out.
The advanced middle pipe shed support is made of hot rolled seamless steel pipes, the circumferential distance is 40cm, the lap joint length is not less than 2m, the external insertion angle is 1-3 degrees, and the support is arranged in the vault range.
And in the step S2, the radial anchor rod for supporting adopts a self-advancing anchor rod, and the primary support adopts a steel frame and steel fiber sprayed concrete.
And S6, twice positioning and twice drilling are carried out on the trolley for going up and down steps, the trolley is located at the position of the lower step during the operation of going up and down step drilling, after the drilling for going up the step is completed, the position of the trolley is moved, and the length of the step is controlled within 8 m.
In the step S6, the trolley for going up and down steps is positioned twice for drilling, when the trolley for going up steps is drilled, the trolley is positioned on the going up steps, and when the trolley for going down steps is drilled, the trolley is positioned on the going down steps; the step length should be greater than 20m.
The front-back distance of the left and right side guide pits in the tunnel is not less than 15m, and the guide pits should advance 30 m-50 m when the guide pits and the middle soil body step are synchronously constructed.
Compared with the prior art, the invention has the following advantages:
the mechanized construction method of the double-side-wall pit guiding method of the tunnel with the ultra-large section is reasonable in structural design, temporary cross braces are omitted based on two vertical temporary supports, the tunnel is divided into three layers for excavation, the upper layer is arranged at first, the lower layer is arranged at last, two three-arm rock drilling jumbo are arranged for drilling, the tunnel excavation work efficiency is greatly improved on the premise that the safety and stability of surrounding rocks of the tunnel are guaranteed, the mechanized construction efficiency can be furthest exerted, and the construction period is effectively shortened.
Drawings
The contents of the description and the references in the drawings are briefly described as follows:
fig. 1 is a sequence diagram of the excavation by the double-side-wall pit guiding method of the invention.
Fig. 2 is a schematic diagram of the excavation by the double-side-wall pit guiding method.
Fig. 3 is a schematic cross-sectional view of a hole drilled by the three-armed jumbo of the present invention.
Figure 4 is a schematic longitudinal section of a three-armed drill jumbo drilling according to the invention.
FIG. 5 is a schematic view of the tapping operation of the present invention.
Detailed Description
The following description of the embodiments of the present invention will explain the present invention in further detail by referring to the accompanying drawings.
As shown in fig. 1 to 5, the mechanized construction method of the double-side-wall pit guiding method for the ultra-large cross-section tunnel comprises the following steps:
s1, excavating rock masses of upper pilot tunnels on the left side and the right side;
s2, adopting an advanced middle pipe shed support and an advanced small pipe support inside the tunnel body;
s3, excavating rock masses of the left and right middle pilot tunnels;
s4, excavating a rock mass of the middle pilot tunnel in the middle position;
s5, excavating a rock mass located in a lower guide pit;
s6, forming an upper layer structure, a middle layer structure and a lower layer structure in the tunnel, simultaneously drilling holes in the upper step, the middle step and the lower step by adopting a three-arm drill jumbo, firstly blasting the upper step during blasting, deslagging to support sprayed concrete, then blasting the middle step and the lower step, and deslagging to support the sprayed concrete.
Wherein, the first and the second end of the pipe are connected with each other,
two vertical temporary supports are arranged in the tunnel to form a pilot hole at two sides and a middle pilot hole; the tunnel face rock mass is reinforced through interim vertical braces, utilizes country rock intensity, cancels interim stull, adopts two three-arm drill jumbo drilling, and broken country rock is detonated in the powder charge, reaches the purpose of two-way eight lane super large section highway tunnel safe quick construction.
Performing advanced geological forecast before the step S1; before drilling holes on the upper step, drilling advanced detection holes at the arch crown and arch springing positions of the tunnel; the depth of the exploratory hole is more than 1m greater than the depth of the cut hole.
The bidirectional eight-lane ultra-large section highway tunnel is excavated and supported by a step method, and an advanced middle-tube shed support and an advanced small conduit support are adopted inside a tunnel body; preferably, the advanced middle pipe shed support is made of hot rolled seamless steel pipes, the circumferential distance is 40cm, the lap joint length is not less than 2m, the external insertion angle is 1-3 degrees, and the support is arranged in the arch crown range; the radial anchor rod adopts a phi 32 self-advancing anchor rod with the length of 8m, and the primary support adopts an H200X 200 steel frame and C30 steel fiber sprayed concrete.
Further: and S6, positioning the trolley for the upper step and the trolley for the lower step twice for drilling, wherein the trolleys are located at the position of the lower step during drilling operation for the upper step and the lower step, and after drilling of the upper step is completed, the position of the trolley is moved, and the length of the step is controlled within 8 m.
Or the trolley for going up and down the step is positioned twice for drilling, when the trolley for going up the step is drilled, the trolley is positioned on the upper step, when the trolley for going down the step is drilled, the trolley for going down the step is positioned on the lower step; the length of the step is more than 20m, so that the working length of the trolley is met.
The front-back distance of the left and right side guide pits in the tunnel is not less than 15m, and the guide pits should advance 30 m-50 m when the guide pits and the middle soil body step are synchronously constructed.
The construction method is based on two vertical temporary supports, the temporary cross brace is cancelled, the tunnel is divided into three layers for excavation, two three-arm rock drilling jumbo drill holes are arranged on the upper layer and the lower layer firstly, on the premise that the safety and stability of surrounding rocks of the tunnel are guaranteed, the tunnel excavation work efficiency is greatly improved, the mechanical construction efficiency can be furthest exerted, and the construction period is effectively shortened.
Preferred specific examples are:
the invention relates to a mechanized construction method of a double-side-wall pit guiding method of a tunnel with an oversized section, which comprises the following operation steps:
1. advanced geological prediction: before drilling on the upper step, drilling advanced exploratory holes at the arch crown and arch springing positions of the tunnel; the depth of the probing hole is more than 1m greater than the depth of the cutting hole;
2. excavating rock masses of the upper pilot tunnels (1) and (2) on the left side and the right side, wherein the front distance and the rear distance are staggered by 15m;
3. the inside of the tunnel body is supported by an advanced middle pipe shed and an advanced small pipe shed, the advanced middle pipe shed is supported by hot rolled seamless steel pipes, the circumferential distance is 40cm, the lap joint length is not less than 2m, the external insertion angle is 1-3 degrees, and the support is arranged in the vault range; the radial anchor rod adopts a phi 32 self-advancing anchor rod with the length of 8m, and the primary support adopts an H200X 200 steel frame and C30 steel fiber sprayed concrete;
4. excavating rock masses of the middle pilot tunnels (3) and (4) on the left side and the right side, respectively staggering the front distance and the rear distance from the rock masses of the middle pilot tunnels (1) and (2) by 5m, and applying primary support;
5. excavating rock masses of the middle pilot tunnels (5) and (6) in the middle, respectively staggering the front distance and the rear distance with the rock masses of the middle pilot tunnels (2) and (4) by 30m, and performing primary support;
6. after the excavation of the soil body of the (6) th part is finished, the excavation of rock bodies of the left and right pilot pits (7) and the (8) lower part is started;
7. finally, excavating the rock mass of the lower part (9);
8. the front-rear distance of the left and right pilot holes is not less than 15m, and the pilot holes should lead 30 m-50 m when the pilot holes and the middle soil body steps are synchronously constructed.
9. The upper step, the middle step and the lower step are drilled by the three-arm drill jumbo simultaneously, the upper step is firstly blasted during blasting, the slag support is used for spraying concrete, the middle step and the lower step are blasted, the slag support is used for spraying concrete, and therefore the secondary approach drilling time of the three-arm drill jumbo is saved;
10. two-time positioning and two-time drilling of the trolley for going up and down steps (when the drilling operation for going up and down steps is carried out, the trolley is positioned at the position of the lower step, and after the drilling operation for going up the steps is completed, the position of the trolley is moved): the step length is controlled within 8 m; twice positioning and twice drilling are carried out on the trolley for going up and down steps (when the trolley is used for drilling the going up steps, the trolley is positioned on the going up steps, and when the trolley is used for drilling the going down steps, the trolley is positioned on the going down steps): the length of the step is more than 20m, so that the working length of the trolley is met. Advanced drilling can be performed in advance, and geological analysis can be automatically performed.
11. And a single excavation section is matched with an excavator to carry out slag skimming and loading, a small slag car is selected according to the difference of the large surface and the small surface of the section of the opening, 1 side dump loader is adopted in a temporary tunnel at the bottom layer, and 3-6 left and right dump trucks are adopted in a transport device to carry slag.
The invention has greater practicability and economy; taking a bidirectional eight-lane highway tunnel in a certain city as an example, the tunnel excavation supporting is carried out by adopting a mechanized construction method of a double-side-wall pit guiding method of the tunnel with the super-large section, the tunnel excavation work efficiency can be greatly improved, the mechanized construction efficiency can be furthest exerted, the tunnel excavation supporting engineering can be excellently completed with lower cost investment, and good economic benefit is obtained.
The above-mentioned technical features can be arbitrarily combined to form a plurality of embodiments of the present invention.
The invention is described above with reference to the accompanying drawings, it is obvious that the specific implementation of the invention is not limited by the above-mentioned manner, and it is within the scope of the invention to adopt various insubstantial modifications of the inventive concept and solution, or to apply the inventive concept and solution directly to other applications without modification.
Claims (8)
1. A mechanized construction method of a double-side-wall pit guiding method for a tunnel with an oversized section is characterized by comprising the following steps: the construction method comprises the following steps:
s1, excavating rock masses of upper pilot tunnels on the left side and the right side;
s2, adopting an advanced middle pipe shed support and an advanced small pipe support inside the tunnel body;
s3, excavating rock masses of the left and right middle pilot tunnels;
s4, excavating a rock mass of the middle pilot tunnel in the middle position;
s5, excavating a rock mass located in a lower guide pit;
s6, forming an upper-layer structure, a middle-layer structure and a lower-layer structure in the tunnel, simultaneously drilling holes in the upper step, the middle step and the lower step by using a three-arm drill jumbo, blasting the upper step during blasting, deslagging the support to spray concrete, blasting the middle step and the lower step, and deslagging the support to spray concrete.
2. The double-side-wall pit-guiding mechanical construction method of the ultra-large section tunnel according to claim 1, characterized in that: two vertical temporary supports are arranged in the tunnel to form two-side pilot holes and a middle pilot hole.
3. The double-side-wall pit-guiding mechanical construction method of the ultra-large section tunnel according to claim 1, characterized in that: and before the step S1, advanced geological prediction is carried out.
4. The mechanized construction method of the double-side-wall pit-guiding method of the ultra-large section tunnel according to claim 1, characterized in that: the advanced middle pipe shed support is made of hot rolled seamless steel pipes, the circumferential distance is 40cm, the lap joint length is not less than 2m, the external insertion angle is 1-3 degrees, and the support is arranged in the vault range.
5. The mechanized construction method of the double-side-wall pit-guiding method of the ultra-large section tunnel according to claim 1, characterized in that: and in the step S2, the radial anchor rod for supporting adopts a self-advancing anchor rod, and the primary support adopts a steel frame and steel fiber sprayed concrete.
6. The mechanized construction method of the double-side-wall pit-guiding method of the ultra-large section tunnel according to claim 1, characterized in that: and S6, positioning the trolley for the upper step and the trolley for the lower step twice for drilling, wherein the trolleys are located at the positions of the lower step during drilling operation for the upper step and the lower step, and after drilling of the upper step is completed, the position of the trolley is moved, and the length of the step is controlled within 8 m.
7. The mechanized construction method of the double-side-wall pit-guiding method of the ultra-large section tunnel according to claim 1, characterized in that: in the step S6, the trolley for the upper step and the trolley for the lower step are positioned twice for drilling, when the upper step is drilled, the trolley is positioned on the upper step, and when the lower step is drilled, the trolley is positioned on the lower step; the step length should be greater than 20m.
8. The mechanized construction method of the double-side-wall pit-guiding method of the ultra-large section tunnel according to claim 1, characterized in that: the front-back distance of the left and right side guide pits in the tunnel is not less than 15m, and the guide pits should advance 30 m-50 m when the guide pits and the middle soil body step are synchronously constructed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210869017.5A CN115163084A (en) | 2022-07-22 | 2022-07-22 | Mechanical construction method for ultra-large section tunnel by double-side-wall pit guiding method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210869017.5A CN115163084A (en) | 2022-07-22 | 2022-07-22 | Mechanical construction method for ultra-large section tunnel by double-side-wall pit guiding method |
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| CN202210869017.5A Pending CN115163084A (en) | 2022-07-22 | 2022-07-22 | Mechanical construction method for ultra-large section tunnel by double-side-wall pit guiding method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114961743A (en) * | 2022-06-02 | 2022-08-30 | 中铁四局集团第三建设有限公司 | Large-section tunnel double-side-wall pit guiding method side-hole synchronous mileage construction method |
| CN115478870A (en) * | 2022-10-12 | 2022-12-16 | 中交（广州）建设有限公司 | Slag tapping structure and method for double-side-wall pit guiding method of underground excavation section of subway |
-
2022
- 2022-07-22 CN CN202210869017.5A patent/CN115163084A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114961743A (en) * | 2022-06-02 | 2022-08-30 | 中铁四局集团第三建设有限公司 | Large-section tunnel double-side-wall pit guiding method side-hole synchronous mileage construction method |
| CN115478870A (en) * | 2022-10-12 | 2022-12-16 | 中交（广州）建设有限公司 | Slag tapping structure and method for double-side-wall pit guiding method of underground excavation section of subway |
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