Large-diameter bidirectional V-shaped through hole roadway roof water spraying prevention and control method

Abstract

The invention provides a large-diameter bidirectional V-shaped through hole roadway roof water spraying prevention and control method, and belongs to the technical field of underground mine water prevention and control. According to the method, by changing the arrangement mode of grouting holes, the grouting holes in the axial center of a roadway are changed into V-shaped arrangement, and the connecting ends of the axial large-diameter V-shaped through holes are communicated; and meanwhile, the diameter of the axial large-diameter V-shaped through hole is increased, so that single-hole grouting can be realized during grouting. The V-shaped grout stopping curtain formed in a single-hole grouting mode can effectively solve the problem that a water spraying channel is left due to the fact that the curtain cannot be effectively lapped during multi-hole grouting. According to the method, the hole diameter of the V-shaped grouting through hole is increased, it can be guaranteed that the grout diffusion distance is longer through a high-pressure grouting mode, the range of the formed V-shaped grouting stopping curtain is larger, the number of grouting holes in the axial section of the roadway is greatly reduced, the grouting procedure is optimized, and the grouting effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of water control in underground mines, and particularly to a method for preventing water leakage on the roof of a roadway with large-diameter bidirectional V-shaped through holes. Background Art

[0002] The treatment of water leakage on the roof of a roadway is a difficult problem in the water control work of mines. During the actual production process, affected by the disturbance of subsequent blasting and mining, some new micro-cracks will be generated in the grouted roadway, or the high-angle micro-cracks originally existing in the rock mass cannot be effectively filled by the grouting material during the previous grouting. These newly generated or remaining micro-cracks will continue to serve as water leakage channels for water bodies, resulting in different degrees of water leakage on the roof of the constructed roadway. The water leakage on the roadway mostly appears in the forms of seepage, dripping, and forming linear flow. Among them, continuous dripping and linear flow will corrode mechanical equipment, permanent support projects, etc., seriously affecting the service life of the roadway.

[0003] In the existing methods for treating water leakage on the roof, the layout form of grouting holes is mostly perpendicular to the roadway contour line, or grouting is carried out synchronously with the construction process of anchor bolts. The layout form of grouting holes determines the final shape of the curtain formed by subsequent grouting operations. When the grouting holes are arranged perpendicular to the roadway contour line, the slurry will diffuse along the axial direction of the grouting holes and form a grout-stop curtain similar to an "O" shape after coagulation. If an ideal water leakage prevention effect is to be achieved, it is necessary to require adjacent "O" - shaped curtains to overlap each other to form a closed slurry curtain area, which has very strict requirements for the diffusion radius of the slurry and the layout of hole spacing. However, in the actual grouting process, affected by construction technology and cost, the layout method of overly dense grouting holes is often not worth the candle. The "O" - shaped curtains of adjacent grouting holes usually cannot achieve effective overlap, especially serious between different rows of grouting holes. Under the action of gravity, water bodies will continue to form linear flow along the gaps left between the "O" - shaped curtains, making the water leakage prevention work unable to be effectively treated.

[0004] In view of this, it is necessary to design a method for preventing water leakage on the roof of a roadway with large-diameter bidirectional V-shaped through holes to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for preventing water leakage on the roof of a roadway with large-diameter bidirectional V-shaped through holes. This method constructs large-diameter V-shaped through holes in two directions, namely the axial direction and the radial direction of the water-leaking roadway, and uses the V-shaped through holes to form a V-shaped grout-stop curtain to solve the problem that the curtains of ordinary grouting processes cannot effectively overlap, and achieve effective treatment of water leakage on the roof of the roadway.

[0006] To achieve the above-mentioned invention purpose, the present invention provides a method for preventing water leakage on the roof of a roadway with large-diameter bidirectional V-shaped through holes, including the following steps: S1, calibrate the water gushing area in the roadway and determine the scope of the water gushing control area; S2, retreat a predetermined distance L from the water gushing control area, and arrange long-distance pressure relief holes perpendicular to the water gushing control area on both side walls and the vault of the roadway respectively; where 15m ≤ L ≤ 20m; In practical applications, the number of the long-distance pressure relief holes can be appropriately adjusted according to the actual situation of hydrophobic pressure relief to meet the grouting requirements under different hydrostatic pressures. The number of holes is directly proportional to the grouting pressure.

[0007] Among them, during the construction of the long-distance pressure relief holes, the consolidation grouting sleeve is consolidated, and the consolidation strength should meet the requirements of the pressure test. After the construction of the long-distance pressure relief holes is completed, orifice devices such as high-pressure gate valves are installed. The opening and closing of the high-pressure gate valve are controlled by the grouting operation. When grouting, the high-pressure gate valve needs to be opened for pressure relief to reduce the grouting pressure and ensure the grouting effect.

[0008] S3, construct axial grouting holes, and the axial grouting holes include an axial large-diameter V-shaped through hole and ordinary grouting holes on both sides; the axial large-diameter V-shaped through hole is symmetrically arranged in an inverted "V" shape at the center of the roadway roof, and the connected ends communicate with each other; the ordinary grouting holes on both sides are arranged closely adjacent to the axial large-diameter V-shaped through hole; During the construction of the axial grouting holes, after consolidating the grouting sleeve and installing orifice devices such as high-pressure gate valves, the grouting operation is carried out.

[0009] S4, carry out the grouting operation of the axial grouting holes. One end of the axial large-diameter V-shaped through hole is used as the grouting port, and the other end is used as the pressure-receiving end; the pressure-receiving end is sealed with a high-strength orifice device, and the pressure-bearing strength of the pressure-receiving end is capable of withstanding 3-5 times the final grouting pressure value; When grouting, one end of the axial large-diameter V-shaped through hole is connected to the grouting pump and used as the grouting end; the other end is blocked by a high-strength orifice structure and used as the grouting pressure-bearing end. The two holes communicate with each other to achieve the single-hole grouting effect. Utilize the special V-shaped form of the grouting hole to form a continuous V-shaped grout curtain at the center of the roadway roof, effectively avoiding the problem of leaving a water gushing channel due to the ineffective overlap of the grout curtain.

[0010] S5, after completing the grouting operation of the axial grouting holes, determine whether it is necessary to construct radial large-diameter V-shaped through holes according to the water gushing situation in the roadway to build a radial V-shaped grout curtain; if necessary, proceed to steps S6-S7; if not, the roof water gushing prevention work is completed; S6, the radial large-diameter V-shaped through holes are interspersed between two adjacent rows of axial large-diameter V-shaped through holes, and the radial large-diameter V-shaped through holes are arranged in an inverted "V" shape in the target area; the connected ends of the radial large-diameter V-shaped through holes communicate with each other; In S7, grouting work for the radially large-diameter V-shaped through holes is carried out; one end of the radially large-diameter V-shaped through hole serves as the grouting port, and the other end serves as the pressure-receiving end; the pressure-receiving end is sealed with a high-strength orifice device, and the pressure-receiving strength of the pressure-receiving end is capable of withstanding 3-5 times the final grouting pressure value.

[0011] As a further improvement of the present invention, in step S5, according to the roadway water seepage situation, constructing the radially large-diameter V-shaped through holes and building the radial V-shaped grout curtain means that: if there is still water seepage after the axial grouting holes are grouted, then the radially large-diameter V-shaped through holes are constructed; if there is no continuous water seepage after the axial grouting holes are grouted, then there is no need to construct the radially large-diameter V-shaped through holes.

[0012] As a further improvement of the present invention, the water seepage control area includes the roadway water seepage area and the areas 2 m and above at both ends beyond the roadway water seepage area, ensuring that the control effect reaches the optimal; a number of the axial large-diameter V-shaped through holes are arranged in parallel throughout the water seepage control area, and the arrangement positions of the axial large-diameter V-shaped through holes at the head and tail rows exceed the boundaries of the roadway water seepage control area.

[0013] As a further improvement of the present invention, a number of the axial large-diameter V-shaped through holes are arranged at equal intervals along the extension direction of the roadway water seepage area, and the exceeding distance of the axial large-diameter V-shaped through holes at the head and tail rows beyond the boundaries of the water seepage control area is 1-2 times the row spacing.

[0014] As a further improvement of the present invention, the opening positions of the axial large-diameter V-shaped through holes are symmetrically arranged on the arch parts on both sides of the roadway, adopting an opposite construction method, the hole diameter ≥ 90 mm, and the angle < 45°. Selecting a large-diameter hole is convenient for controlling the mutual penetration of the two holes during construction and increasing the slurry diffusion radius.

[0015] As a further improvement of the present invention, the spacing between adjacent axial large-diameter V-shaped through holes ≤ 2 m.

[0016] As a further improvement of the present invention, the ordinary grouting holes on both sides are symmetrically arranged left and right with the central axis of the axial large-diameter V-shaped through hole as the center line. The number of the ordinary grouting holes arranged on both sides depends on the size of the roadway contour. According to the water seepage situation, the number of ordinary grouting holes can be appropriately increased or decreased, generally 4-6.

[0017] As a further improvement of the present invention, the value range of the included angle a between the long-distance pressure relief hole and the roadway contour line is: 10° ≤ a ≤ 20°, and the final hole diameter of the long-distance pressure relief hole ≤ 75 mm.

[0018] It should be noted that the length of the long-distance pressure relief hole is determined according to the scope of the water spraying control area, and it is necessary to ensure that the long-distance pressure relief hole passes through the entire water spraying control area.

[0019] As a further improvement of the present invention, the compressive strength of the compression ends of the axial large-diameter V-shaped through holes and the radial large-diameter V-shaped through holes is > 30 MPa.

[0020] The beneficial effects of the present invention are as follows: 1. The present invention provides a method for preventing and controlling roof water spraying in a roadway with large-diameter bidirectional V-shaped through holes. By changing the arrangement of grouting holes, the grouting holes at the axial center of the roadway are changed to a V-shaped arrangement, and at the same time, the diameter of the V-shaped grouting holes is increased. During construction, the ends of the grouting holes are made to penetrate, and single-hole grouting is realized during grouting. The V-shaped grout-stop 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 a water spraying channel. Moreover, this method increases the aperture of the V-shaped grouting through holes, and through the method of high-pressure grouting, it can ensure that the slurry diffuses farther, the range of the formed V-shaped grout-stop curtain is larger, greatly reducing the number of grouting holes in the axial section of the roadway, optimizing the grouting process, and improving the grouting effect.

[0021] 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 spraying situation of the roadway 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 grout-stop curtains between different rows of grouting holes cannot be effectively overlapped.

[0022] 3. The method for preventing and controlling roof water spraying in a roadway with large-diameter bidirectional V-shaped through holes in the present invention constructs continuous V-shaped grout-stop curtains in both the axial and radial directions of the roadway, realizing the effective control of roadway water spraying, which is of great significance for the water prevention and control work in underground mines. Description of the Drawings

[0023] Figure 1 It is a diagram of the arrangement of conventional roof water spraying grouting holes and the slurry diffusion state.

[0024] Figure 2 It is a diagram of the method for preventing and controlling roof water spraying in a roadway with large-diameter bidirectional V-shaped through holes.

[0025] Figure 3 For Figure 2 Top view.

[0026] Figure 4 It is a diagram of the arrangement of large-diameter bidirectional V-shaped through hole grouting holes and the slurry diffusion state.

[0027] Description of reference numerals: 1 - roadway water gushing area; 2 - long-distance pressure relief hole; 3 - ordinary grouting hole; 4 - large-diameter axial V-shaped through hole; 5 - axial V-shaped grout curtain; 6 - large-diameter radial V-shaped through hole; 7 - radial V-shaped grout curtain; 8 - water gushing treatment area. Detailed implementation manners

[0028] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Here, it should also be noted that in order to avoid obscuring the present invention due to unnecessary details, only the structures and / or processing steps closely related to the solution of the present invention are shown in the drawings, while other details less related to the present invention are omitted.

[0030] In addition, it should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0031] During construction by ordinary methods, the grouting holes are perpendicular to the roadway contour line. When grouting, the grout diffuses along the axial direction of the grouting holes. Each hole will form its own grout curtain with different diffusion distances of the grout. If the grout curtains do not overlap and close, water gushing gaps will be left, as Figure 1 shown.

[0032] Please refer to Figures 2 to 4 shown. The present invention provides a method for preventing and controlling roadway roof water gushing by using large-diameter bidirectional V-shaped through holes, including the following steps: S1, demarcate the roadway water gushing area 1 and determine the scope of the water gushing treatment area 8; Specifically, the water gushing treatment area 8 includes the roadway water gushing area 1 and the areas extending 2 m or more at both ends beyond the roadway water gushing area 1. By setting it in this way, the treatment effect can be ensured to be optimal.

[0033] In this embodiment, the water gushing treatment area 8 extends 2 m at each end beyond the roadway water gushing area 1.

[0034] S2, retreat a predetermined distance L from the water gushing treatment area 8, and arrange long-distance pressure relief holes 2 perpendicular to the water gushing treatment area 8 on both side walls and the crown of the roadway; wherein, 15 m ≤ L ≤ 20 m.

[0035] Among them, the value range of the included angle a between the long-distance pressure relief hole 2 and the roadway contour line is: 10° ≤ a ≤ 20°, and the final hole diameter of the long-distance pressure relief hole 2 ≤ 75 mm. In this embodiment, the included angle between the long-distance pressure relief hole 2 and the roadway contour line is 15°, and the final hole diameter is 75 mm.

[0036] The length of the long-distance pressure relief hole 2 is determined according to the scope of the water gushing treatment area, and it is necessary to ensure that the long-distance pressure relief hole 2 passes through the entire water gushing treatment area 8. In this embodiment, the length of the roadway water gushing area 1 is 20 m, the length of the long-distance pressure relief hole 2 is 45 m, and the long-distance pressure relief hole 2 passes through the entire water gushing treatment area 8.

[0037] In this embodiment, the number of long-distance pressure relief holes 2 is 3, including one long-distance pressure relief hole 2 at the center of the roadway roof and two long-distance pressure relief holes 2 symmetrically arranged on both sides.

[0038] It should be noted that in actual application, 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 directly proportional to the grouting pressure.

[0039] Among them, during the construction of the long-distance pressure relief hole 2, the consolidation grouting sleeve is consolidated, and the consolidation strength should meet the requirements of the pressure test. In this embodiment, the consolidation strength > 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 valve are controlled by the grouting operation. When grouting, the high-pressure gate valve needs to be opened for pressure relief to reduce the grouting pressure and ensure the grouting effect.

[0040] S3. Construct axial grouting holes. The axial grouting holes include an axial large-diameter V-shaped through hole 4 and ordinary grouting holes 3 on both sides. The axial large-diameter V-shaped through hole 4 is symmetrically arranged in an inverted "V" shape at the center of the roadway roof, and the connected ends are interconnected. The ordinary grouting holes 3 on both sides are symmetrically arranged closely on the left and right of the axial large-diameter V-shaped through hole 4.

[0041] Specifically, several axial grouting holes are arranged side by side to cover the entire water gushing treatment area 8, and the arrangement positions of the axial grouting holes at the head and tail rows exceed the boundary of the roadway water gushing area 1. The exceeding distance of the axial grouting holes at the head and tail rows exceeding the boundary of the roadway water gushing area 1 is 1-2 times the row spacing.

[0042] The opening positions of the axial large-diameter V-shaped through holes 4 are symmetrically arranged at the arch positions on both sides of the roadway, and the opposite construction method is adopted. The hole diameter ≥ 90 mm, and the angle < 45°. Selecting a large-diameter hole is convenient for controlling the mutual penetration of the two holes during construction and increasing the slurry diffusion radius.

[0043] The spacing between adjacent axially large-diameter V-shaped through holes 4 ≤ 2 m. In this embodiment, several axially large-diameter V-shaped through holes 4 are arranged at equal intervals along the extension direction of the roadway water gushing area 1. The first and last rows extend 2 m beyond the boundary of the roadway water gushing area 1.

[0044] The number of ordinary grouting holes 3 arranged on both sides depends on the size of the roadway contour, generally 4 - 6.

[0045] In this embodiment, 2 ordinary grouting holes 3 are arranged on each of the left and right sides of the roadway. The opening positions of the ordinary grouting holes 3 are arranged on both sides of the roadway, with a hole diameter of 40 mm, arranged vertically along microcracks, an opening spacing of 0.9 m, a final hole spacing of 3 m, and a length of 5 m. The ordinary grouting holes 3 are arranged as supplementary holes for the axially large-diameter V-shaped through holes 4.

[0046] During the construction of the axial grouting holes, after installing the consolidation grout-stop casing and orifice devices such as high-pressure gate valves, the grouting work is carried out.

[0047] S4. Carry out the grouting work for the axial grouting holes. One end of the axially large-diameter V-shaped through hole 4 serves as the grouting port, and the other end serves as the compression end. The compression end is sealed with a high-strength orifice device, and the compression strength of the compression end can withstand 3 - 5 times the final grouting pressure value; in this embodiment, the compression strength of the compression end > 30 MPa.

[0048] Specifically, during grouting, one end of the axially large-diameter V-shaped through hole 4 is connected to the grouting pump and serves as the grouting end; the other end is blocked by a high-strength orifice structure and serves as the grouting pressure-bearing end. The two holes communicate with each other to achieve the single-hole grouting effect. Using the special V-shaped form of this grouting hole, a continuous axial V-shaped grout-stop curtain 5 is formed at the center of the roadway roof, effectively avoiding the problem of leaving a water gushing channel due to the ineffective lap of the grout-stop curtain.

[0049] S5. After completing the grouting work for the axial grouting holes, determine whether it is necessary to construct the radially large-diameter V-shaped through holes 6 according to the roadway water gushing situation and build the radial V-shaped grout-stop curtain 7; if necessary, proceed to steps S6 - S7; if not, the roof water gushing prevention work is completed; Specifically, if there is still water gushing after the grouting of the axial grouting holes, then construct the radially large-diameter V-shaped through holes 6; if there is no continuous water gushing after the grouting of the axial grouting holes, then it is not necessary to construct the radially large-diameter V-shaped through holes 6.

[0050] S6. The radially large-diameter V-shaped through holes 6 are arranged in an interspersed manner between adjacent two 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; 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 sprinkling.

[0051] One end of the radial large diameter V-shaped through hole 6 is used as a grouting port, and the other end is used as a 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.

[0052] The compressive strength of the pressure-bearing end of the radially large-diameter V-shaped through hole 6 is greater than 30 MPa.

[0053] In particular, the radial large-diameter V-shaped through holes 6 do not need to be arranged continuously, and can be arranged interspersed between two adjacent rows of axial large-diameter V-shaped through holes 4 according to actual needs. The arrangement form of the radial large-diameter V-shaped through holes 6 is the same as that of the axial large-diameter V-shaped through holes 4. The radial large-diameter V-shaped through holes 6 are constructed in a targeted manner according to the watering condition after the axial grouting holes are grouted. If there is no continuous watering condition after the axial grouting holes are constructed, the radial large-diameter V-shaped through holes 6 may not be arranged, thereby reducing the workload.

[0054] In summary, the present invention provides a method for preventing and controlling water spraying on the roof of a large-diameter bidirectional V-shaped through-hole tunnel. By changing the arrangement of the grouting holes, the grouting holes in the axial center of the tunnel are changed into 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-stopping 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 spraying 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-stopping 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.

[0055] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A prevention and control method for roof water gushing in a roadway with a large-diameter two-way V-shaped through hole, characterized in that, It includes the following steps: S1, calibrate the roadway water seepage area and determine the scope of the water seepage control area; S2, retreat a predetermined distance L from the water seepage control area, and arrange long-distance pressure relief holes vertically towards the water seepage control area on both side walls and the arch crown of the roadway; where, 15m ≤ L ≤ 20m; S3, construct axial grouting holes, and the axial grouting holes include an axial large-diameter V-shaped through hole and ordinary grouting holes on both sides; the axial large-diameter V-shaped through hole is symmetrically arranged in an inverted "V" shape at the center of the roadway roof, and the connected ends are interconnected; the ordinary grouting holes on both sides are arranged closely to the axial large-diameter V-shaped through hole; S4, carry out the grouting work of the axial grouting holes, one end of the axial large-diameter V-shaped through hole is used as the grouting port, and the other end is used as the pressure-receiving end; the pressure-receiving end is sealed with a high-strength orifice device, and the pressure-bearing strength of the pressure-receiving end is capable of withstanding 3 - 5 times the final grouting pressure value; S5, after completing the grouting work of the axial grouting holes, determine whether it is necessary to construct a radial large-diameter V-shaped through hole and build a radial V-shaped grout curtain according to the roadway water seepage situation; if necessary, proceed to steps S6 - S7; if not, the roof water seepage prevention work is completed; S6, the radial large-diameter V-shaped through hole is inserted between two adjacent rows of axial large-diameter V-shaped through holes, and the radial large-diameter V-shaped through hole is arranged in an inverted "V" shape in the target area; the connected ends of the radial large-diameter V-shaped through hole are interconnected; S7, carry out the grouting work of the radial large-diameter V-shaped through hole; one end of the radial large-diameter V-shaped through hole is used as the grouting port, and the other end is used as the pressure-receiving end; the pressure-receiving end is sealed with a high-strength orifice device, and the pressure-bearing strength of the pressure-receiving end is capable of withstanding 3 - 5 times the final grouting pressure value.

2. The method for preventing roof water spray in large-diameter two-way V-shaped through-hole roadway according to claim 1, characterized in that, In step S5, according to the roadway water seepage situation, constructing a radial large-diameter V-shaped through hole and building a radial V-shaped grout curtain means that if there is still water seepage after the grouting of the axial grouting holes, then construct the radial large-diameter V-shaped through hole; if there is no continuous water seepage after the grouting of the axial grouting holes, then it is not necessary to construct the radial large-diameter V-shaped through hole.

3. The method for preventing roof water spraying in a large-diameter two-way V-shaped through-hole roadway according to claim 1, characterized in that, The water seepage control area includes the roadway water seepage area and the area extending 2m or more beyond both ends of the roadway water seepage area; several axial large-diameter V-shaped through holes are arranged in parallel throughout the water seepage control area, and the arrangement positions of the first and last rows of axial large-diameter V-shaped through holes extend beyond the boundary of the roadway water seepage area.

4. The method for preventing roof water leakage in a large-diameter two-way V-shaped through-hole roadway according to claim 3, characterized in that, Several axial large-diameter V-shaped through holes are arranged at equal intervals along the extension direction of the roadway water seepage area, and the exceeding distance of the first and last rows of axial large-diameter V-shaped through holes beyond the boundary of the water seepage control area is 1 - 2 times the row spacing.

5. The method for preventing roof water spray in a large-diameter two-way V-shaped through-hole roadway according to claim 3, characterized in that, The opening positions of the axial large-diameter V-shaped through holes are symmetrically arranged on the arch parts on both sides of the roadway, and the opposite construction method is adopted, with the hole diameter ≥ 90mm and the angle < 45°.

6. The method for preventing roof water spray in a large-diameter two-way V-shaped through-hole roadway according to claim 3, characterized in that The spacing between adjacent axial large-diameter V-shaped through holes ≤ 2m.

7. The method for preventing roof water spray in a roadway with a large-diameter two-way V-shaped through hole according to claim 1, characterized in that The common grouting holes on both sides are symmetrically arranged on the left and right with the central axis of the axial large-diameter V-shaped through hole as the center line.

8. The method for preventing roof water spray in a large-diameter two-way V-shaped through-hole roadway according to claim 1, characterized in that, The included angle α between the long-distance pressure relief hole and the roadway contour line ranges from 10° ≤ α ≤ 20°, and the final hole diameter of the long-distance pressure relief hole ≤ 75 mm.

9. The method for preventing roof water spray in a large-diameter two-way V-shaped through-hole roadway according to claim 1, characterized in that The long-distance pressure relief hole passes through the entire water spraying treatment area.

10. The method for preventing roof water leakage in a large-diameter two-way V-shaped through-hole roadway according to claim 1, characterized in that, The compressive strengths of the compressive ends of the axial large-diameter V-shaped through hole and the radial large-diameter V-shaped through hole are both > 30 MPa.

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