Tunnel consolidation grouting structure and construction method

Abstract

This invention relates to the field of water conservancy and hydropower engineering technology, and discloses a tunnel consolidation grouting structure and construction method. Multiple sets of circumferential consolidation grouting holes are provided within the concrete lining of the sidewalls and bottom slab of the horizontal tunnel section. These multiple sets of circumferential consolidation grouting holes are arranged radiating outwards from the horizontal tunnel section as the center. Multiple sets of horizontal consolidation grouting holes are provided within the surrounding rock of the lower section of the shaft. These multiple sets of horizontal consolidation grouting holes are evenly distributed in multiple horizontal planes spaced apart along the height direction, and the horizontal consolidation grouting holes in each horizontal plane are arranged radiating outwards from the lower section of the shaft as the center. Vertical consolidation grouting holes are provided within the concrete lining of the slope around the upper section of the shaft, and these vertical consolidation grouting holes are evenly arranged on multiple circles of different radii centered on the upper section of the shaft. By combining the above-mentioned specific structures and construction methods, grouting zones belonging to different locations and directions are organically integrated, ensuring the integrity and airtightness of the grouting system and significantly improving the overall stability and impermeability of the surrounding rock in complex tunnel structures, especially at key locations where vertical shafts and horizontal tunnels intersect.

Description

Technical Field

[0001] This invention relates to the field of water conservancy and hydropower engineering technology, specifically to a tunnel consolidation grouting structure and construction method. Background Technology

[0002] In water conservancy and hydropower projects, tunnels are classified into vertical shafts, horizontal tunnels, and inclined tunnels according to their orientation. Hydraulic tunnels, such as gate shafts, typically contain both vertical shafts and horizontal tunnels. To improve the integrity and stability of the surrounding rock mass, consolidation grouting is used to inject cement grout into the fissures of the rock mass to fill them.

[0003] Currently, the grouting method used for vertical shafts is typically horizontal grouting with a cover, which involves grouting along the horizontal direction of the tunnel after the concrete lining. Its advantages include increased grouting pressure and guaranteed grouting effect, but its disadvantages include the need for a relatively large construction space and high construction difficulty. For hydraulic tunnels such as gate shafts, the space after the concrete lining is extremely narrow, generally only allowing for the size of a gate. Therefore, consolidation grouting after the concrete lining is very difficult.

[0004] Therefore, it is necessary to provide a tunnel consolidation grouting structure and construction method that is flexible, convenient, safe and reliable to solve the problems existing in the prior art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a flexible, convenient and safe and reliable tunnel consolidation grouting structure and construction method.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A tunnel consolidation grouting structure is provided. The tunnel includes a horizontal tunnel section, a lower vertical shaft section, an upper vertical shaft section, and a gate shaft top. The sidewalls and bottom slabs of the horizontal tunnel section are lined with concrete. Multiple sets of circumferential consolidation grouting holes are provided in the concrete lining of the sidewalls and bottom slabs of the horizontal tunnel section. The multiple sets of circumferential consolidation grouting holes are arranged radiating outward from the horizontal tunnel section as the center. Multiple sets of horizontal consolidation grouting holes are provided in the surrounding rock of the lower section of the shaft. The multiple sets of horizontal consolidation grouting holes are evenly distributed in multiple horizontal planes spaced apart along the height direction, and the horizontal consolidation grouting holes in each horizontal plane are arranged in a circle radiating outward from the lower section of the shaft as the center. The upper section of the shaft is surrounded by a slope concrete lining. Vertical consolidation grouting holes are provided in the slope concrete lining along the vertical direction. The vertical consolidation grouting holes are evenly arranged on a circle with different radii centered on the upper section of the shaft.

[0008] As a further improvement to the above technical solution: The inner walls of both the lower and upper sections of the shaft are lined with concrete.

[0009] As a further improvement to the above technical solution: Positioning pipes for consolidation grouting are pre-embedded in the concrete lining of the horizontal tunnel section, the lower section of the vertical shaft, and the upper section of the vertical shaft. Positioning pipes for consolidation grouting are also pre-embedded in the initial support of the horizontal tunnel section, the lower section of the vertical shaft, and the upper section of the vertical shaft.

[0010] As a further improvement to the above technical solution: The vertical consolidation grouting holes are arranged in at least two circles with different radii, centered on the upper section of the shaft.

[0011] As a further improvement to the above technical solution: At least 18 sets of vertical consolidation grouting holes are set in each ring.

[0012] As a further improvement to the above technical solution: The horizontal consolidation grouting holes are arranged in at least 16 groups evenly in each horizontal plane.

[0013] As a further improvement to the above technical solution: The surrounding rock geological conditions of the lower section of the shaft are weakly weathered to fresh rock.

[0014] A construction method for a tunnel consolidation grouting structure as described above includes the following steps: Initial support and embedded parts construction: After the excavation of the horizontal tunnel section, the lower section of the vertical shaft and the upper section of the vertical shaft are completed, the initial support operation including shotcrete, wire mesh and anchor bolts is carried out on the tunnel wall; and positioning pipes for consolidation grouting are pre-embedded in the initial support. Horizontal consolidation grouting in the lower section of the shaft: Horizontal consolidation grouting is performed in the surrounding rock of the lower section of the shaft through the positioning pipe pre-embedded in the lower section of the shaft. Permanent concrete lining construction: Concrete lining construction is carried out on the horizontal tunnel section, the lower section of the vertical shaft, the upper section of the vertical shaft, and the slope connected to the upper section of the vertical shaft, and positioning pipes for consolidation grouting are pre-embedded in each concrete lining structure simultaneously. Circumferential consolidation grouting of the tunnel section: Circumferential consolidation grouting is carried out through the positioning pipe in the concrete lining of the tunnel section to the circumferential consolidation grouting holes in the sidewall and bottom plate of the tunnel section. Vertical consolidation grouting of the upper section of the shaft: Vertical consolidation grouting is carried out in the vertical consolidation grouting holes in the upper section of the shaft through the positioning pipes pre-embedded in the slope concrete lining. Construction of the top structure of the gate well: Construct the concrete structure of the top of the gate well.

[0015] As a further improvement to the above technical solution: When performing vertical consolidation grouting on the upper section of the shaft, the bottom depth of the vertical consolidation grouting hole is connected to the horizontal consolidation grouting hole in the first horizontal plane at the top of the upper section of the shaft.

[0016] Compared with the prior art, the advantages of the present invention are as follows: (1) A tunnel consolidation grouting structure and construction method of the present invention, the tunnel includes a horizontal tunnel section, a lower vertical shaft section, an upper vertical shaft section and a gate shaft top. The sidewalls and bottom plate of the horizontal tunnel section are provided with concrete lining. Multiple sets of circumferential consolidation grouting holes are provided in the concrete lining of the sidewalls and bottom plate of the horizontal tunnel section. The multiple sets of circumferential consolidation grouting holes are arranged outward from the horizontal tunnel section as the center. Multiple sets of horizontal consolidation grouting holes are provided in the surrounding rock of the lower vertical shaft section. The multiple sets of horizontal consolidation grouting holes are evenly distributed in multiple horizontal planes spaced apart along the height direction. The horizontal consolidation grouting holes in each horizontal plane are arranged outward from the lower vertical shaft section as the center. The upper vertical shaft section is filled with slope concrete lining. Vertical consolidation grouting holes are provided in the slope concrete lining along the vertical direction. The vertical consolidation grouting holes are evenly arranged on multiple circles of different radii with the upper vertical shaft section as the center. By innovatively combining the above-mentioned specific structural combinations and sequential construction methods, grouting zones belonging to different locations and directions are organically integrated, ensuring the integrity and airtightness of the grouting system, and significantly improving the overall stability and impermeability of the surrounding rock in complex tunnel structures, especially at key locations where vertical shafts and horizontal tunnels intersect.

[0017] (2) Through the above-mentioned settings, the present invention makes full use of the surrounding rock conditions. In places with strong bearing capacity, shotcrete is used as the foundation surface for consolidation grouting. In places with poor surrounding rock, a vertical grouting method with covered heavy concrete is used, which fully realizes the principle of adapting to local conditions, reducing construction costs, and improving project quality. In particular, it improves the level of grouting in surrounding rock with poor geological conditions. By making full use of the effective construction space, the construction difficulty is reduced and the safety space is greater. Attached Figure Description

[0018] Figure 1 This is a longitudinal cross-sectional schematic diagram of a tunnel consolidation grouting structure according to an embodiment of the present invention; Figure 2 for Figure 1 Sectional view at point AA; Figure 3 for Figure 1 Sectional view at point BB; Figure 4 for Figure 1 Sectional view at CC; Figure 5 for Figure 1 Sectional view at point DD; Figure 6This is a schematic diagram of the installation of the positioning pipe in the lower section of the vertical shaft in an embodiment of the present invention; Figure 7 This is a schematic diagram of the installation of the positioning pipe in the flat tunnel section in an embodiment of the present invention; Figure 8 This is a schematic diagram of the installation of the positioning pipe in the upper section of the vertical shaft in an embodiment of the present invention.

[0019] The markings in the diagram are as follows: 1. Horizontal tunnel section; 2. Lower section of vertical shaft; 3. Upper section of vertical shaft; 4. Top of gate shaft; 5. Concrete lining; 6. Slope concrete lining; 7. Initial support; 8. Vertical consolidation grouting hole; 9. Horizontal consolidation grouting hole; 10. Circumferential consolidation grouting hole; 11. Side wall; 12. Bottom plate; 13. Positioning pipe; 14. Concrete structure at the top of gate shaft. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Please see Figure 1-8 A preferred embodiment of the present invention discloses a tunnel consolidation grouting structure. The tunnel includes a horizontal tunnel section 1, a lower shaft section 2, an upper shaft section 3, and a gate shaft top 4. The sidewalls 11 and bottom slab 12 of the horizontal tunnel section 1 are lined with concrete lining 5. Multiple sets of circumferential consolidation grouting holes 10 are provided within the concrete lining 5 of the sidewalls 11 and bottom slab 12 of the horizontal tunnel section 1. These multiple sets of circumferential consolidation grouting holes 10 are arranged radiating outwards from the horizontal tunnel section 1 as the center. Multiple sets of horizontal consolidation grouting holes 9 are provided within the surrounding rock of the lower shaft section 2. Multiple sets of horizontal consolidation grouting holes 9 are evenly distributed in multiple horizontal planes spaced apart along the height direction, and the horizontal consolidation grouting holes 9 in each horizontal plane are arranged radiating outwards from the lower section 2 of the shaft as the center; the upper section 3 of the shaft is filled with slope concrete lining 6, and vertical consolidation grouting holes 8 are provided in the slope concrete lining 6 along the vertical direction. The vertical consolidation grouting holes 8 are evenly arranged on multiple circles of different radii with the upper section 3 of the shaft as the center. These consolidation grouting holes form a closed grouting system.

[0022] The inner walls of both the lower section 2 and the upper section 3 of the shaft are lined with concrete lining 5.

[0023] Positioning pipes 13 for consolidation grouting are pre-embedded in the concrete lining 5 of the horizontal tunnel section 1, the lower section 2 of the vertical shaft and the upper section 3 of the vertical shaft. Positioning pipes 13 for consolidation grouting are also pre-embedded in the initial support 7 of the horizontal tunnel section 1, the lower section 2 of the vertical shaft and the upper section 3 of the vertical shaft.

[0024] The vertical consolidation grouting holes 8 are arranged in at least two circles with different radii centered on the upper section 3 of the shaft.

[0025] At least 18 sets of vertical consolidation grouting holes are set in each ring.

[0026] The horizontal consolidation grouting holes 9 are arranged in at least 16 groups evenly in each horizontal plane.

[0027] The surrounding rock geological conditions of the lower section of the shaft are weakly weathered to fresh rock.

[0028] A construction method for a tunnel consolidation grouting structure as described above includes the following steps: Initial support 7 and pre-embedded parts construction: After the excavation of the horizontal tunnel section 1, the lower section 2 and the upper section 3 of the shaft are completed, the initial support 7 operation including shotcrete, wire mesh and anchor bolts is carried out on the tunnel wall; and positioning pipes 13 for consolidation grouting are pre-embedded in the initial support 7. Horizontal consolidation grouting of the lower section 2 of the shaft: Horizontal consolidation grouting is carried out through the positioning pipe 13 pre-embedded in the lower section 2 of the shaft to the horizontal consolidation grouting hole 9 in the surrounding rock of the lower section 2 of the shaft. Construction of permanent concrete lining 5: Concrete lining 5 is constructed for the horizontal tunnel section 1, the lower section 2 of the vertical shaft, the upper section 3 of the vertical shaft, and the slope connected to the upper section 3 of the vertical shaft. Positioning pipes 13 for consolidation grouting are pre-embedded in each concrete lining 5 structure simultaneously. Circumferential consolidation grouting of horizontal tunnel section 1: Circumferential consolidation grouting is carried out on the side wall 11 and the circumferential consolidation grouting holes 10 in the bottom plate 12 of the horizontal tunnel section 1 through the positioning pipe 13 in the concrete lining 5 of the horizontal tunnel section 1. Vertical consolidation grouting of the upper section 3 of the shaft: Vertical consolidation grouting is performed on the vertical consolidation grouting holes 8 in the upper section 3 of the shaft through the positioning pipes 13 pre-embedded in the slope concrete lining 6. It should be noted that the bottom depth of this vertical consolidation grouting should be ensured to connect with the horizontal consolidation grouting hole 9 in the first horizontal plane at the top of the upper section 3 of the shaft. This step constitutes the upper vertical reinforcement zone of the closed grouting system, thus forming a complete and closed pressure-bearing and seepage-proof system together with the aforementioned lower horizontal reinforcement zone and middle circumferential reinforcement zone.

[0029] Construction of the top structure of the gate well: Construction of the concrete structure 14 at the top of the gate well.

[0030] When performing vertical consolidation grouting of the upper section 3 of the shaft, the bottom depth of the vertical consolidation grouting hole 8 is connected to the horizontal consolidation grouting hole 9 in the first horizontal plane at the top of the upper section 3 of the shaft.

[0031] This embodiment innovatively combines grouting zones belonging to different locations and directions through the above-mentioned specific structural combination and sequential construction method, ensuring the integrity and airtightness of the grouting system, and significantly improving the overall stability and impermeability of the surrounding rock in complex tunnel structures, especially in key areas where vertical shafts and horizontal tunnels intersect.

[0032] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A tunnel consolidation grouting structure, the tunnel comprising a horizontal tunnel section, a lower vertical shaft section, an upper vertical shaft section, and a gate shaft top, characterized in that, The sidewalls and bottom slab of the tunnel section are lined with concrete. Multiple sets of circumferential consolidation grouting holes are provided in the concrete lining of the sidewalls and bottom slab of the tunnel section. The multiple sets of circumferential consolidation grouting holes are arranged radiating outward from the tunnel section as the center. Multiple sets of horizontal consolidation grouting holes are provided in the surrounding rock of the lower section of the shaft. The multiple sets of horizontal consolidation grouting holes are evenly distributed in multiple horizontal planes spaced apart along the height direction, and the horizontal consolidation grouting holes in each horizontal plane are arranged in a circle radiating outward from the lower section of the shaft as the center. The upper section of the shaft is surrounded by a slope concrete lining. Vertical consolidation grouting holes are provided in the slope concrete lining along the vertical direction. The vertical consolidation grouting holes are evenly arranged on a circle with different radii centered on the upper section of the shaft.

2. The tunnel consolidation grouting structure according to claim 1, characterized in that, The inner walls of both the lower and upper sections of the shaft are lined with concrete.

3. The tunnel consolidation grouting structure according to claim 2, characterized in that, Positioning pipes for consolidation grouting are pre-embedded in the concrete lining of the horizontal tunnel section, the lower section of the vertical shaft, and the upper section of the vertical shaft. Positioning pipes for consolidation grouting are also pre-embedded in the initial support of the horizontal tunnel section, the lower section of the vertical shaft, and the upper section of the vertical shaft.

4. The tunnel consolidation grouting structure according to claim 1, characterized in that, The vertical consolidation grouting holes are arranged in at least two circles with different radii, centered on the upper section of the shaft.

5. The tunnel consolidation grouting structure according to claim 4, characterized in that, At least 18 sets of vertical consolidation grouting holes are set in each ring.

6. The tunnel consolidation grouting structure according to claim 1, characterized in that, The horizontal consolidation grouting holes are arranged in at least 16 groups evenly in each horizontal plane.

7. The tunnel consolidation grouting structure according to claim 1, characterized in that, The surrounding rock geological conditions of the lower section of the shaft are weakly weathered to fresh rock.

8. A construction method for a tunnel consolidation grouting structure as described in any one of claims 1-7, characterized in that, Includes the following steps: Initial support and embedded parts construction: After the excavation of the horizontal tunnel section, the lower section of the vertical shaft and the upper section of the vertical shaft are completed, the initial support operation including shotcrete, wire mesh and anchor bolts is carried out on the tunnel wall; and positioning pipes for consolidation grouting are pre-embedded in the initial support. Horizontal consolidation grouting in the lower section of the shaft: Horizontal consolidation grouting is performed in the surrounding rock of the lower section of the shaft through the positioning pipe pre-embedded in the lower section of the shaft. Permanent concrete lining construction: Concrete lining construction is carried out on the horizontal tunnel section, the lower section of the vertical shaft, the upper section of the vertical shaft, and the slope connected to the upper section of the vertical shaft, and positioning pipes for consolidation grouting are pre-embedded in each concrete lining structure simultaneously. Circumferential consolidation grouting of the tunnel section: Circumferential consolidation grouting is carried out through the positioning pipe in the concrete lining of the tunnel section to the circumferential consolidation grouting holes in the sidewall and bottom plate of the tunnel section. Vertical consolidation grouting of the upper section of the shaft: Vertical consolidation grouting is carried out in the vertical consolidation grouting holes in the upper section of the shaft through the positioning pipes pre-embedded in the slope concrete lining. Construction of the top structure of the gate well: Construct the concrete structure of the top of the gate well.

9. The construction method of the tunnel consolidation grouting structure according to claim 8, characterized in that, When performing vertical consolidation grouting on the upper section of the shaft, the bottom depth of the vertical consolidation grouting hole is connected to the horizontal consolidation grouting hole in the first horizontal plane at the top of the upper section of the shaft.

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