A tunnel retreat deep hole grouting reinforcement structure

Abstract

The present application relates to the field of tunnel construction reinforcement, and in particular to a tunnel retreat deep hole grouting reinforcement structure, characterized in that it includes a grouting wall arranged in the tunnel and a plurality of coagulation blocks arranged on the outer periphery of the tunnel, the plurality of coagulation blocks are arranged along the tunnel excavation direction, the plurality of coagulation blocks are arranged at an angle, and there is an overlapping portion between adjacent coagulation blocks, the plurality of coagulation blocks are formed by inserting a grouting pipe into the same grouting hole position for grouting multiple times, and the grouting pipe is inserted for grouting multiple times at different angles, and the angles between the plurality of coagulation blocks along the tunnel excavation direction and the tunnel excavation direction are successively reduced. The present application can improve the grouting reinforcement effect on the water-rich sand layer.

Description

Technical Field

[0001] The present application relates to the field of tunnel construction reinforcement, and in particular to a tunnel retreat type deep hole grouting reinforcement structure. Background Art

[0002] When excavating a tunnel in a weak soil layer with a high water content, such as a water-rich sand layer, in order to prevent the face (the working face that continuously advances when excavating the tunnel) from collapsing sand layers and other safety accidents, the face and the soil in front of it must be pre-reinforced. The existing pre-reinforcement method usually uses the full-section deep hole grouting method to reinforce the stratum before tunnel excavation.

[0003] Full-section deep hole grouting means that before tunnel excavation, multiple grouting holes are drilled in the entire range of the tunnel face, and grouting is then carried out in the grouting holes. After the slurry solidifies, it can approximately form a columnar structure extending along the length of the tunnel, which can play a role in reinforcing the soil.

[0004] With respect to the above-mentioned related technologies, the inventors believe that the existing full-section deep hole grouting generally adopts one-time hole drilling, and the drill rod grouting range is fixed. If the grouting area needs to be increased, the equipment requirements are high and the soil reinforcement effect is difficult to guarantee. Utility Model Content

[0005] In order to improve the grouting reinforcement effect on the water-rich sand layer, the present application provides a tunnel retreat deep hole grouting reinforcement structure.

[0006] The present application provides a tunnel retreat deep hole grouting reinforcement structure, which adopts the following technical solution:

[0007] A tunnel retreat deep hole grouting reinforcement structure comprises a grouting wall arranged in the tunnel and a plurality of coagulation blocks arranged on the outer periphery of the tunnel. The plurality of coagulation blocks are arranged along the tunnel excavation direction, the plurality of coagulation blocks are arranged at an angle, and there are overlapping parts between adjacent coagulation blocks.

[0008] By adopting the above technical solution, multiple coagulants are formed by grouting. The multiple coagulants are arranged at angles and have overlapping parts. Compared with the coagulants formed by traditional deep hole grouting methods, the coagulants in this application are fuller, more solid, and have higher structural strength, and can effectively reinforce the water-rich sand layer.

[0009] Optionally, a plurality of the coagulation blocks are formed by inserting a grouting pipe into the same grouting hole for multiple times for grouting, and the grouting pipe is inserted for grouting at different angles for multiple times.

[0010] Optionally, the angles between the plurality of coagulation blocks along the tunnel excavation direction and the tunnel excavation direction decrease successively.

[0011] Optionally, the coagulated block is a block formed by coagulating water glass and cement-water glass double slurry.

[0012] By adopting the above technical solution, water glass is injected first to achieve a water-stopping effect, and then cement-water glass double liquid slurry is injected. In the water-rich sand layer, the two slurries can be better condensed into agglomerated blocks, which are not easy to crack and have a better reinforcement effect.

[0013] Optionally, a steel anchor rod is provided in the slurry stopping wall, and the steel anchor rod is anchored into the unexcavated soil layer.

[0014] Optionally, connecting steel bars are provided outside the tunnel excavation contour line, and the connecting steel bars are anchored into the plurality of the coagulation blocks.

[0015] By adopting the above technical solution, the integrity of the multiple coagulation blocks is improved, and the reinforcement effect of the coagulation blocks is further improved.

[0016] In summary, the present application includes at least one of the following beneficial technical effects:

[0017] 1. By drilling holes at angles multiple times at the same hole position and performing grouting multiple times, the injected slurry is made fuller and more abundant, so that the agglomerates formed by grouting have a better reinforcement effect on the soil layer, ensuring the grouting reinforcement effect on the water-rich sand layer;

[0018] 2. First inject water glass to stop water, then inject cement water glass double liquid slurry, in the water-rich sand layer, the two slurries can be better condensed into agglomerates, not easy to crack, and play a better reinforcement effect;

[0019] 3. The connecting steel bars improve the integrity of multiple agglomerates and further enhance the reinforcement effect of the agglomerates. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the cross-sectional structure in an embodiment of the present application.

[0021] Explanation of the accompanying reference numerals: 1. Agglomerate; 11. Overlapping portion; 2. Stop wall; 21. Steel bar anchor rod; 3. Grouting hole position; 4. Connecting steel bar; 5. Excavation contour line. DETAILED DESCRIPTION

[0022] The following is combined with Figure 1 This application is described in further detail.

[0023] The present application embodiment discloses a tunnel retreat type deep hole grouting reinforcement structure. Figure 1 The tunnel retreat deep hole grouting reinforcement structure includes a plurality of coagulation blocks 1 and a grouting wall 2. The plurality of coagulation blocks 1 can effectively stop water and reinforce the soil layer.

[0024] The grout-stopping wall 2 is arranged within the excavation contour line 5. The grout-stopping wall 2 is cast with C20 concrete. The thickness of the grout-stopping wall 2 is set to 50 mm. A steel anchor rod 21 is arranged within the grout-stopping wall 2. The steel anchor rod 21 is arranged in a plum blossom shape and covers the entire grout-stopping wall 2. The steel anchor rod 21 is anchored into the unexcavated soil layer. The grout-stopping wall 2 is used to withstand the grouting pressure and prevent grout from leaking or running into the tunnel during grouting.

[0025] The coagulation block 1 is formed by condensing the slurry injected into the outer soil layer of the tunnel excavation contour line 5. Since the water content in the water-rich sand layer is too high, two slurries, water glass and cement-water glass double-liquid slurry, are used for grouting. Water glass is injected first, which mainly plays a water-stopping role, and then cement-water glass double-liquid slurry is injected. The two slurries are mixed and condensed to form the coagulation block 1. Compared with the traditional method of only using cement-water glass double-liquid slurry for grouting, the coagulation block 1 in this application has a better water-stopping effect and is more suitable for water-rich sand layers.

[0026] A plurality of coagulation blocks 1 are provided, and the plurality of coagulation blocks 1 are arranged along the tunnel excavation direction; the coagulation blocks 1 are formed by drilling and grouting through the same grouting hole position 3 for multiple times, and the grouting hole position 3 is arranged at a position close to the grouting wall 2, and each grouting pipe is inserted at an angle to the tunnel excavation direction, so that the coagulation blocks 1 formed by the grouting are arranged at an angle to the tunnel excavation direction, and the angles between the plurality of coagulation blocks 1 and the tunnel excavation direction decrease successively along the tunnel excavation direction.

[0027] In order to enhance the reinforcement effect, the angle between adjacent coagulation blocks 1 and the tunnel excavation direction is controlled between 4°-30°, so that there is an overlapping part 11 between two adjacent coagulation blocks 1 or three adjacent coagulation blocks 1, so that multiple coagulation blocks 1 form a whole, which can improve the reinforcement effect.

[0028] Connecting steel bars 4 are inserted into the soil layer outside the excavation contour line 5. The connecting steel bars 4 are also set at an angle to the direction of tunnel excavation, and the connecting steel bars 4 are inserted into multiple agglomerates 1, which further improves the integrity of the multiple agglomerates 1 and makes the reinforcement effect of the agglomerates 1 better.

[0029] The implementation principle of a tunnel retreat deep hole grouting reinforcement structure in an embodiment of the present application is as follows: by drilling holes at an angle multiple times at the same hole position and performing grouting multiple times, the injected slurry is made fuller and fuller, so that the agglomerate 1 formed by the grouting has a better reinforcement effect on the soil layer, thereby ensuring the grouting reinforcement effect on the water-rich sand layer. In addition, the agglomerate 1 in the present application is grouted twice with two slurries of water glass and cement water glass. The water glass slurry injected first can effectively stop water, and then injecting cement water glass can make the condensed agglomerate 1 denser and have higher structural strength, thereby improving the reinforcement effect on the water-rich sand layer.

[0030] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A tunnel retreat deep hole grouting reinforcement structure, characterized in that: The invention comprises a mortar stop wall (2) arranged in a tunnel and a plurality of coagulation blocks (1) arranged on the outer periphery of the tunnel, wherein the plurality of coagulation blocks (1) are arranged along the tunnel excavation direction, the plurality of coagulation blocks (1) are arranged at an angle, and adjacent coagulation blocks (1) have overlapping portions (11).

2. A tunnel retreat deep hole grouting reinforcement structure according to claim 1, characterized in that: The plurality of agglomerates (1) are formed by inserting a grouting pipe into the same grouting hole (3) for multiple times for grouting, and the grouting pipe is inserted for grouting at different angles for multiple times.

3. A tunnel retreat deep hole grouting reinforcement structure according to claim 2, characterized in that: The angles between the plurality of coagulation blocks (1) along the tunnel excavation direction and the tunnel excavation direction decrease successively.

4. The tunnel retreat deep hole grouting reinforcement structure according to claim 1, characterized in that: The coagulated block (1) is a block formed by coagulating water glass and cement-water glass double slurry.

5. The tunnel retreat deep hole grouting reinforcement structure according to claim 1, characterized in that: A steel anchor rod (21) is arranged in the mortar stop wall (2), and the steel anchor rod (21) is anchored in the unexcavated soil layer.

6. The tunnel retreat deep hole grouting reinforcement structure according to claim 1, characterized in that: A connecting steel bar (4) is provided outside the tunnel excavation contour line (5), and the connecting steel bar (4) is anchored into a plurality of the coagulation blocks (1).

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