Water spraying prevention method for large diameter bidirectional V-shaped through hole roadway roof

Abstract

The present invention provides a method for preventing and controlling water spraying on the roof of a tunnel with a large diameter, bidirectional V-shaped through hole, which belongs to the technical field of underground mine water prevention and control. This method changes the arrangement of the grouting holes, changes the grouting holes in the axial center of the tunnel into a V-shaped arrangement, and the connecting end of the axial large diameter V-shaped through hole is connected; at the same time, the diameter of the axial large diameter V-shaped through hole is increased, and single-hole grouting can be achieved during grouting. The V-shaped grouting curtain formed by the single-hole grouting method can effectively solve the problem that the curtain cannot be effectively overlapped and a water spraying channel is left during multi-hole grouting. In addition, this method increases the aperture of the V-shaped grouting through hole, and the high-pressure grouting method can ensure that the slurry diffuses farther, and the formed V-shaped grouting curtain has a larger range, which greatly reduces the number of grouting holes in the axial section of the tunnel, optimizes the grouting process, and improves the grouting effect.

Description

Technical Field

[0001] The present invention relates to the technical field of underground mine water prevention and control, and in particular to a method for preventing and controlling water from being sprayed on the roof of a tunnel with a large diameter, bidirectional V-shaped through hole. Background Art

[0002] Tunnel roof water management is a challenging issue in mine water prevention and control. During actual production, subsequent blasting and mining disturbances can create new microcracks in grouting tunnels, or pre-existing high-angle microcracks in the rock mass that cannot be effectively filled by the grouting material during the previous grouting. These newly created or remaining microcracks continue to serve as channels for water flow, resulting in varying degrees of water flow in the completed tunnel roof. Tunnel water flow often manifests as seepage, dripping, and linear flow. Continuous dripping and linear flow can corrode mechanical equipment and permanent support structures, seriously impacting the service life of the tunnel.

[0003] In existing roof water control methods, grouting holes are often arranged perpendicular to the roadway contour or grouting is performed simultaneously with the anchor bolting process. The arrangement of grouting holes determines the final shape of the curtain formed by subsequent grouting operations. When grouting holes are arranged perpendicular to the roadway contour, the slurry diffuses along the axial direction of the grouting hole, solidifying to form a "0"-shaped grouting curtain. To achieve ideal water control, adjacent "0"-shaped curtains must overlap to form a closed slurry curtain area. This places strict demands on the slurry diffusion radius and hole spacing. However, in actual grouting, due to construction technology and cost constraints, an overly dense grouting hole arrangement often outweighs the benefits. The "0"-shaped curtains of adjacent grouting holes often fail to effectively overlap, especially between grouting holes in different rows. Under the influence of gravity, water continues to form linear flows along the gaps left between the "0"-shaped curtains, making water control ineffective.

[0004] In view of this, it is necessary to design a large-diameter bidirectional V-shaped through-hole tunnel roof water spraying prevention method to solve the above problems. Summary of the Invention

[0005] The present invention aims to provide a method for preventing and controlling water dripping from tunnel roofs caused by large-diameter, bidirectional V-shaped through-holes. This method constructs large-diameter V-shaped through-holes in both the axial and radial directions of the water dripping tunnel. These holes form a V-shaped grouting curtain, resolving the problem of conventional grouting processes with curtains that cannot be effectively overlapped, effectively controlling water dripping from tunnel roofs.

[0006] To achieve the above-mentioned object, the present invention provides a method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through-hole roadway, comprising the following steps:

[0007] S1, calibrate the tunnel watering area and determine the scope of the watering treatment area;

[0008] S2, retreating a predetermined distance L from the water treatment area, and arranging long-distance pressure relief holes perpendicular to the water treatment area on the sides and arch of the roadway; wherein 15m≤L≤20m;

[0009] In practical applications, the number of the long-distance pressure relief holes can be appropriately adjusted according to the actual situation of hydrophobic pressure reduction to meet the grouting requirements under different hydrostatic pressures. The number of holes is proportional to the grouting pressure.

[0010] During the construction of long-distance pressure relief holes, the grouting casing is consolidated, and the consolidation strength must meet the requirements of the pressure test. After the long-distance pressure relief holes are completed, the orifice devices such as high-pressure gate valves are installed. The opening and closing of the high-pressure gate valves are controlled by the grouting process. During grouting, the high-pressure gate valves must be opened to relieve pressure, reduce grouting pressure, and ensure grouting effectiveness.

[0011] S3, constructing axial grouting holes, the axial grouting holes including axial large-diameter V-shaped through holes and common grouting holes on both sides; the axial large-diameter V-shaped through holes are symmetrically arranged in an inverted "V" shape at the center of the roadway roof, and the connected ends are interconnected; the common grouting holes on both sides are arranged adjacent to the axial large-diameter V-shaped through holes;

[0012] During the construction of the axial grouting holes, grouting work is carried out after consolidating the grouting casing and installing the high-pressure gate valve and other orifice devices.

[0013] S4, grouting the axial grouting hole, with one end of the axial large-diameter V-shaped through hole serving as the grouting port and the other end serving as the pressure-bearing end; the pressure-bearing end is sealed with a high-strength orifice device, and the pressure-bearing end has a compressive strength capable of withstanding 3-5 times the final grouting pressure;

[0014] During grouting, one end of the large-diameter V-shaped through-hole is connected to a grouting pump, serving as the grouting end; the other end is sealed with a high-strength orifice structure, serving as the grouting pressure-bearing end. The two holes are interconnected, achieving a single-hole grouting effect. The unique V-shaped grouting hole forms a continuous V-shaped grouting curtain at the center of the roadway roof, effectively avoiding the problem of leaving a water channel due to the ineffective overlap of the grouting curtain.

[0015] S5, after completing the grouting work of the axial grouting holes, determine whether it is necessary to construct radial large-diameter V-shaped through holes and build radial V-shaped grouting curtains based on the water spraying conditions in the roadway; if necessary, proceed to steps S6-S7; if not, the roof water spraying prevention work is completed;

[0016] S6, the radially large-diameter V-shaped through holes are interspersed between two adjacent rows of axially large-diameter V-shaped through holes, and the radially large-diameter V-shaped through holes are arranged in an inverted "V" shape in the target area; the connected ends of the radially large-diameter V-shaped through holes are interconnected;

[0017] S7, perform grouting work on the radial large diameter V-shaped through hole; one end of the radial large diameter V-shaped through hole serves as the grouting port, and the other end serves as the pressure end; the pressure end is sealed with a high-strength orifice device, and the pressure strength of the pressure end is capable of withstanding 3-5 times the final grouting pressure value.

[0018] As a further improvement of the present invention, in step S5, according to the water sprinkling condition of the tunnel, radial large diameter V-shaped through holes are constructed, and a radial V-shaped grouting curtain is constructed, which means: if water sprinkling still exists after the grouting of the axial grouting hole is completed, the radial large diameter V-shaped through hole is constructed; if there is no further water sprinkling after the grouting of the axial grouting hole is completed, the radial large diameter V-shaped through hole does not need to be constructed.

[0019] As a further improvement of the present invention, the water sprinkling treatment area includes the tunnel water sprinkling area and the area 2m and above beyond both ends of the tunnel water sprinkling area to ensure that the treatment effect is optimal; a number of the axial large-diameter V-shaped through holes are arranged in parallel in the entire water sprinkling treatment area, and the arrangement positions of the first and last rows of axial large-diameter V-shaped through holes exceed the boundary of the tunnel water sprinkling treatment area.

[0020] As a further improvement of the present invention, several of the axial large-diameter V-shaped through holes are arranged at equal intervals along the extension direction of the tunnel water sprinkling area, and the axial large-diameter V-shaped through holes in the first and last rows exceed the boundary of the water sprinkling treatment area by 1-2 times the row spacing.

[0021] As a further improvement to the present invention, the axially large-diameter V-shaped through holes are symmetrically arranged at the arch positions on both sides of the roadway, using a counter-construction method. The hole diameter is ≥90mm and the angle is less than 45°. The large diameter facilitates the control of the interconnection between the two holes during construction and increases the slurry diffusion radius.

[0022] As a further improvement of the present invention, the spacing between adjacent axial large-diameter V-shaped through holes is ≤2m.

[0023] As a further improvement of the present invention, the common grouting holes on both sides are arranged symmetrically about the central axis of the axially large-diameter V-shaped through-hole. The number of common grouting holes on both sides depends on the size of the roadway profile and can be appropriately increased or decreased according to the water spraying conditions, generally 4-6.

[0024] As a further improvement of the present invention, the value range of the angle a between the long-distance pressure relief hole and the tunnel contour line is: 10°≤a≤20°, and the final hole diameter of the long-distance pressure relief hole is ≤75mm.

[0025] It should be noted that the length of the long-distance pressure relief hole is determined by the scope of the water sprinkling treatment area, and it is necessary to ensure that the long-distance pressure relief hole passes through the entire water sprinkling treatment area.

[0026] As a further improvement of the present invention, the compressive strength of the pressure-bearing ends of the axially large-diameter V-shaped through hole and the radially large-diameter V-shaped through hole are both greater than 30 MPa.

[0027] The beneficial effects of the present invention are:

[0028] 1. The present invention provides a method for preventing and controlling water dripping on the roof of a tunnel with a large diameter and bidirectional V-shaped through hole. By changing the arrangement of the grouting holes, the grouting holes in the axial center of the tunnel are changed to a V-shaped arrangement, and at the same time, the diameter of the V-shaped grouting holes is increased, so that the ends of the grouting holes are penetrated during construction, and single-hole grouting is achieved during grouting. The V-shaped grouting curtain formed by the single-hole grouting method can effectively solve the problem that the curtain cannot be effectively overlapped during multi-hole grouting, leaving behind a water dripping channel. In addition, this method increases the aperture of the V-shaped grouting through hole, and the high-pressure grouting method can ensure that the slurry diffuses farther, and the V-shaped grouting curtain formed has a larger range, which greatly reduces the number of grouting holes in the axial section of the tunnel, optimizes the grouting process, and improves the grouting effect.

[0029] 2. The radial V-shaped through holes in the present invention serve as supplementary holes for the axial V-shaped through holes. According to the water sprinkling conditions of the tunnel after grouting of the axial V-shaped through holes, the radial V-shaped through holes are arranged in a targeted manner to realize the construction of large-diameter bidirectional V-shaped through holes, effectively solving the problem that the grouting curtains between different rows of grouting holes cannot be effectively overlapped.

[0030] 3. The large-diameter bidirectional V-shaped through-hole tunnel roof water spraying prevention method of the present invention realizes the effective control of tunnel water spraying by constructing a continuous V-shaped slurry-stopping curtain in both the axial and radial directions of the tunnel, which is of great significance to the water prevention and control work of underground mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a diagram of the layout of conventional roof slab water grouting holes and the slurry diffusion status.

[0032] Figure 2 This is a diagram of the water sprinkling prevention method for the roof of a large-diameter bidirectional V-shaped through-hole tunnel.

[0033] Figure 3 for Figure 2 Top view of .

[0034] Figure 4 This is a diagram of the layout of grouting holes and slurry diffusion status of large-diameter bidirectional V-shaped through holes.

[0035] Explanation of the accompanying figures: 1-tunnel water sprinkling area; 2-long distance pressure relief hole; 3-ordinary grouting hole; 4-axial large diameter V-shaped through hole; 5-axial V-shaped grouting curtain; 6-radial large diameter V-shaped through hole; 7-radial V-shaped grouting curtain; 8-water sprinkling treatment area. DETAILED DESCRIPTION

[0036] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] It should also be noted here that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0038] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0039] During the common construction method, the grouting hole is perpendicular to the roadway outline. During grouting, the slurry diffuses along the axial direction of the grouting hole. Each hole will form its own slurry curtain as the slurry diffusion distance varies. If the slurry curtain overlaps and is not closed, water gaps will be left. Figure 1 shown.

[0040] See also Figures 2 to 4 As shown, the present invention provides a method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through-hole roadway, comprising the following steps:

[0041] S1, calibrate the tunnel watering area 1 and determine the scope of the watering treatment area 8;

[0042] Specifically, the water sprinkling treatment area 8 includes the tunnel water sprinkling area 1 and the area 2m and above beyond both ends of the tunnel water sprinkling area 1. Such an arrangement can ensure that the treatment effect is optimal.

[0043] In this embodiment, the water spraying treatment area 8 extends 2 meters beyond both ends of the tunnel water spraying area 1.

[0044] S2, retreat a predetermined distance L from the water spraying treatment area 8, and arrange long-distance pressure relief holes 2 vertical to the water spraying treatment area 8 on the sides and arch of the tunnel; among them, 15m≤L≤20m.

[0045] The angle a between the long-distance pressure relief hole 2 and the roadway contour line is in the range of 10°≤a≤20°, and the final hole diameter of the long-distance pressure relief hole 2 is ≤75mm. In this embodiment, the angle between the long-distance pressure relief hole 2 and the roadway contour line is 15°, and the final hole diameter is 75mm.

[0046] The length of the long-distance pressure relief hole 2 is determined by the scope of the water treatment area, and it is necessary to ensure that the long-distance pressure relief hole 2 passes through the entire water treatment area 8. In this embodiment, the length of the tunnel water treatment area 1 is 20m, and the length of the long-distance pressure relief hole 2 is 45m, and the long-distance pressure relief hole 2 passes through the entire water treatment area 8.

[0047] In this embodiment, the number of the long-distance pressure relief holes 2 is three, including one long-distance pressure relief hole 2 in the center of the tunnel roof and two long-distance pressure relief holes 2 symmetrically arranged on both sides.

[0048] It should be noted that in actual applications, the number of long-distance pressure relief holes can be appropriately adjusted according to the actual situation of hydrophobic pressure reduction to meet the grouting requirements under different hydrostatic pressures. The number of holes is proportional to the grouting pressure.

[0049] During the construction of the long-distance pressure relief hole 2, the grouting casing is consolidated to a strength that meets the requirements of the pressure test. In this embodiment, the consolidation strength is >20 MPa. After the construction of the long-distance pressure relief hole 2 is completed, orifice devices such as high-pressure gate valves are installed. The opening and closing of the high-pressure gate valves are controlled by the grouting process. During grouting, the high-pressure gate valves must be opened to relieve pressure, reduce grouting pressure, and ensure grouting effectiveness.

[0050] S3: Construct axial grouting holes. These holes include large-diameter axial V-shaped through-holes 4 and standard grouting holes 3 on both sides. These large-diameter V-shaped through-holes 4 are symmetrically arranged in an inverted V shape in the center of the roadway roof, with their ends interconnected. Standard grouting holes 3 on both sides are symmetrically arranged adjacent to the large-diameter V-shaped through-holes 4.

[0051] Specifically, several axial grouting holes are arranged side by side throughout the entire water sprinkling treatment area 8, and the arrangement positions of the first and last rows of axial grouting holes exceed the boundary of the tunnel water sprinkling area 1, and the excess distance of the first and last rows of axial grouting holes beyond the boundary of the tunnel water sprinkling area 1 is 1-2 times the row spacing.

[0052] The axially large-diameter V-shaped through holes (4) are symmetrically arranged at the arches on both sides of the roadway, using a counter-construction method. The hole diameter is ≥90mm and the angle is less than 45°. The large diameter facilitates the control of the two holes' interconnection during construction and increases the slurry diffusion radius.

[0053] The spacing between adjacent axial large-diameter V-shaped through holes 4 is ≤ 2m. In this embodiment, a plurality of axial large-diameter V-shaped through holes 4 are arranged at equal intervals along the extension direction of the tunnel water spraying area 1. The first and last rows extend 2m beyond the boundary of the tunnel water spraying area 1.

[0054] The number of common grouting holes 3 arranged on both sides depends on the size of the tunnel profile, and is generally 4-6.

[0055] In this embodiment, two common grouting holes 3 are arranged on each side of the roadway. The common grouting holes 3 are located on both sides of the roadway, with a diameter of 40 mm and a vertical micro-crack arrangement. The opening spacing is 0.9 m, the final hole spacing is 3 m, and the length is 5 m. The common grouting holes 3 are arranged as supplementary holes to the axial large-diameter V-shaped through-holes 4.

[0056] During the construction of the axial grouting holes, grouting work is carried out after consolidating the grouting casing and installing the high-pressure gate valve and other orifice devices.

[0057] S4: Grouting is performed on the axial grouting holes. One end of the large-diameter V-shaped through-hole 4 serves as the grouting port, and the other end serves as the pressure-bearing port. The pressure-bearing port is sealed with a high-strength port seal. The pressure-bearing port is designed to withstand 3-5 times the final grouting pressure. In this embodiment, the pressure-bearing port is >30 MPa.

[0058] Specifically, during grouting, one end of the large-diameter axial V-shaped through-hole 4 is connected to the grouting pump, serving as the grouting end; the other end is sealed with a high-strength orifice structure, serving as the grouting pressure-bearing end. The two holes are interconnected, achieving a single-hole grouting effect. The unique V-shaped grouting hole forms a continuous axial V-shaped grouting curtain 5 at the center of the roadway roof, effectively avoiding the problem of water dripping channels left behind due to the ineffective overlap of the grouting curtain.

[0059] S5, after completing the grouting work of the axial grouting hole, determine whether it is necessary to construct a radial large-diameter V-shaped through hole 6 and build a radial V-shaped grout-stopping curtain 7 based on the water spraying condition of the roadway; if necessary, proceed to steps S6-S7; if not, the roof water spraying prevention work is completed;

[0060] Specifically, if water dripping still occurs after the axial grouting holes are grouted, a radial large-diameter V-shaped through hole 6 is constructed; if water dripping does not continue after the axial grouting holes are grouted, a radial large-diameter V-shaped through hole 6 does not need to be constructed.

[0061] S6, radially large-diameter V-shaped through holes 6 are interspersed between two adjacent rows of axially large-diameter V-shaped through holes 4, and the radially large-diameter V-shaped through holes 6 are arranged in an inverted "V" shape in the target area; the connected ends of the radially large-diameter V-shaped through holes 6 are interconnected;

[0062] S7, grouting work is carried out on the radial large-diameter V-shaped through hole 6 to complete the entire construction process of top plate water sprinkling.

[0063] One end of the radially large V-shaped through hole 6 serves as the grouting port, and the other end serves as the pressure-bearing end, which is sealed with a high-strength orifice device. The pressure-bearing end has a compressive strength capable of withstanding 3-5 times the final grouting pressure.

[0064] The compressive strength of the pressure-bearing end of the radially large-diameter V-shaped through hole 6 is greater than 30 MPa.

[0065] In particular, the radially large-diameter V-shaped through-holes 6 do not need to be arranged continuously; instead, they can be interspersed between two adjacent rows of axially large-diameter V-shaped through-holes 4 as needed. The arrangement of the radially large-diameter V-shaped through-holes 6 is similar to that of the axially large-diameter V-shaped through-holes 4. The radially large-diameter V-shaped through-holes 6 are constructed in a targeted manner based on the water flow conditions after grouting the axial grouting holes. If no further water flow conditions are expected after grouting the axial grouting holes, the radially large-diameter V-shaped through-holes 6 can be omitted, thus reducing workload.

[0066] In summary, the present invention provides a method for preventing and controlling water dripping on the roof of a tunnel with a large diameter, bidirectional V-shaped through hole. By changing the arrangement of the grouting holes, the grouting holes in the axial center of the tunnel are changed to a V-shaped arrangement, so that the ends of the grouting holes are connected, and at the same time, the diameter of the V-shaped grouting holes is increased to achieve single-hole grouting. The V-shaped grouting curtain formed by the single-hole grouting method can effectively solve the problem that the curtain cannot be effectively overlapped during multi-hole grouting, leaving behind a water dripping channel. In addition, this method increases the aperture of the V-shaped grouting through hole, and through high-pressure grouting, it can ensure that the slurry diffuses farther, and the range of the formed V-shaped grouting curtain is larger, which greatly reduces the number of grouting holes in the axial section of the tunnel, optimizes the grouting process, and improves the grouting effect.

[0067] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through-hole tunnel, characterized in that: The following steps are involved: S1, calibrate the tunnel watering area and determine the scope of the watering treatment area; S2, retreating a predetermined distance L from the water treatment area, and arranging long-distance pressure relief holes perpendicular to the water treatment area on the sides and arch of the roadway; wherein 15m≤L≤20m; S3, constructing axial grouting holes, the axial grouting holes including axial large-diameter V-shaped through holes and common grouting holes on both sides; the axial large-diameter V-shaped through holes are symmetrically arranged in an inverted "V" shape at the center of the roadway roof, with the connected ends interconnected; the common grouting holes on both sides are arranged adjacent to the axial large-diameter V-shaped through holes; S4, grouting the axial grouting hole, with one end of the axial large-diameter V-shaped through hole serving as the grouting port and the other end serving as the pressure-bearing end; the pressure-bearing end is sealed with a high-strength orifice device, and the pressure-bearing end has a compressive strength capable of withstanding 3-5 times the final grouting pressure; S5, after completing the grouting work of the axial grouting holes, determine whether it is necessary to construct radial large-diameter V-shaped through holes and build radial V-shaped grouting curtains based on the water spraying conditions in the roadway; if necessary, proceed to steps S6-S7; if not, the roof water spraying prevention work is completed; S6, the radially large-diameter V-shaped through holes are interspersed between two adjacent rows of axially large-diameter V-shaped through holes, and the radially large-diameter V-shaped through holes are arranged in an inverted "V" shape in the target area; the connected ends of the radially large-diameter V-shaped through holes are interconnected; S7, perform grouting work on the radial large diameter V-shaped through hole; one end of the radial large diameter V-shaped through hole serves as the grouting port, and the other end serves as the pressure end; the pressure end is sealed with a high-strength orifice device, and the pressure strength of the pressure end is capable of withstanding 3-5 times the final grouting pressure value.

2. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 1 is characterized in that: In step S5, according to the water sprinkling condition of the tunnel, radial large-diameter V-shaped through holes are constructed, and a radial V-shaped grouting-stopping curtain is constructed, which means: if water sprinkling still exists after the axial grouting holes are grouted, the radial large-diameter V-shaped through holes are constructed; if there is no further water sprinkling after the axial grouting holes are grouted, there is no need to construct the radial large-diameter V-shaped through holes.

3. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 1 is characterized in that: The water sprinkling treatment area includes the tunnel water sprinkling area and the area 2m and above beyond both ends of the tunnel water sprinkling area; a plurality of axial large-diameter V-shaped through holes are arranged in parallel in the entire water sprinkling treatment area, and the arrangement positions of the first and last rows of axial large-diameter V-shaped through holes exceed the boundaries of the tunnel water sprinkling area.

4. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 3 is characterized in that: Several axial large-diameter V-shaped through holes are arranged at equal intervals along the extension direction of the tunnel water sprinkling area, and the axial large-diameter V-shaped through holes in the first and last rows exceed the boundary of the water sprinkling treatment area by 1-2 times the row spacing.

5. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 3 is characterized in that: The opening positions of the axial large-diameter V-shaped through holes are arranged symmetrically at the arch positions on both sides of the tunnel, and a facing construction method is adopted. The hole diameter is ≥90mm and the angle is <45°.

6. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 3 is characterized in that: The spacing between adjacent axial large-diameter V-shaped through holes is ≤2m.

7. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 1, characterized in that: The common grouting holes on both sides are arranged symmetrically with the central axis of the axial large-diameter V-shaped through hole as the center line.

8. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 1, characterized in that: The value range of the angle a between the long-distance pressure relief hole and the tunnel contour line is: 10°≤a≤20°, and the final hole diameter of the long-distance pressure relief hole is ≤75mm.

9. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 1, characterized in that: The long-distance pressure relief hole passes through the entire water treatment area.

10. The method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through hole tunnel according to claim 1, characterized in that: The compressive strength of the pressure-bearing ends of the axially large-diameter V-shaped through hole and the radially large-diameter V-shaped through hole are both greater than 30 MPa.

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