Construction technology of in-situ drilling in underground roadway water inrush treatment chamber

Abstract

The application discloses a construction technology of in-cavern drilling for treatment of sudden gushing water in a roadway chamber underground, and comprises the following steps: step A: arranging a drilling cavern chamber in a mountain according to the sudden gushing water condition and on-site construction condition; step B: designing the position of a grouting hole underground and determining a roadway-penetrating trajectory route according to the construction condition of the roadway underground; and step C: drilling and constructing the grouting hole by using a composite drilling technology according to the roadway-penetrating trajectory route, wherein the directional casing is first penetrated into the roadway and then lowered in the process of constructing the grouting hole on the water-passing roadway. The construction technology of in-cavern drilling for treatment of sudden gushing water in a roadway chamber underground provided by the application has high construction precision, the drilling construction path is not much different from the designed trajectory in the drilling process, the roadway is successfully bypassed in the drilling construction process, and the interference on the stability of the stratum is small. In addition, the drilling construction technology has high efficiency, low cost and good plugging effect in treatment of sudden gushing water underground.

Description

Technical Field

[0001] This invention relates to the field of drilling construction technology. Specifically, it relates to the drilling construction process for controlling sudden water inrush in underground mine tunnels. Background Technology

[0002] Due to the complexity of terrain, landforms, and geological conditions, sudden water inrushes often occur in underground roadways during mining construction due to adverse geological conditions. Controlling these inrushes typically involves sealing the flowing water within the roadway through material feeding and grouting reinforcement. In some construction sites, such as certain metal mining areas with steep slopes and high mountains, surface construction is not feasible, and drilling operations are entirely conducted underground, with limited working space. Before feeding materials and grouting into the water-bearing roadway, through-hole drilling is usually required to inject aggregate and grout into the target roadway. During drilling towards the target roadway, due to geological constraints, other non-water-bearing roadways may be encountered during the drilling process from the borehole to the target roadway. Therefore, the drilling path needs to be designed to bypass these roadways to prevent drilling fluid leakage and damage to surrounding roadways, thus requiring high drilling precision. In addition, when drilling through tunnels, depending on the terrain and geological conditions, the drilling trajectory often intersects the tunnel at an angle, making tunneling more difficult. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to provide a drilling construction process for treating sudden water inrush in underground roadways, so as to solve the problems of poor drilling accuracy and high difficulty in the process of treating sudden water inrush in underground roadways.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0005] The drilling process for controlling sudden water inrush in underground mine tunnels includes the following steps:

[0006] Step A: Based on the sudden water inrush situation in the tunnel and the on-site construction conditions, drill holes are arranged inside the mountain;

[0007] Step B: Based on the construction conditions of the underground roadway, design the location of the underground grouting holes and determine the tunnel passage trajectory;

[0008] Step C: Based on the tunnel trajectory, use composite drilling technology to drill and construct grouting holes. During the construction of grouting holes in the water-passing tunnel, first drill through the tunnel and then install directional casing.

[0009] In the above-mentioned drilling construction process for controlling sudden water inrush in underground roadways, step B involves opening 3 to 5 through-road grouting holes in roadways with a water flow velocity of less than 3 m / min; opening 5 to 10 through-road grouting holes in roadways with a water flow velocity greater than or equal to 3 m / min; opening one main grouting hole at the water inrush point in the roadway; and opening 3 to 5 water-guiding channel grouting holes in the surrounding rock around the water inrush point. The water-guiding channel grouting holes are either the main grouting hole at the water inrush point or branch holes of the through-road grouting holes.

[0010] The above-mentioned drilling construction process for controlling sudden water inrush in underground roadways involves the following: the grouting holes for the through-passage are arranged along the direction of water flow in the water-passing roadway (there may be only one or multiple water-passing roadways for sudden water inrush), and the distance between two adjacent grouting holes for the through-passage is 10-20m; the grouting holes for the water-diverting channels are distributed around the sudden water inrush point in the roadway, and the distance between two adjacent grouting holes for the water-diverting channels is 30-50m, and the distance between the grouting holes for the water-diverting channels and the sudden water inrush point in the roadway is 20-100m (the specific design can be based on the geological formation to infer the water inrush channel).

[0011] The above-mentioned drilling construction process for the treatment of sudden water inrush in underground roadways involves two water-passing roadways outside the water inrush point, one of which has a water flow velocity of less than 3 m / min, and the other has a water flow velocity of greater than 3 m / min. In step B, three through-road grouting holes T1, T2, and T3 are respectively opened on the water-passing roadway with a water flow velocity of less than 3 m / min; five through-road grouting holes H1, H2, H3, H4, and H5 are respectively opened on the water-passing roadway with a water flow velocity greater than or equal to 3 m / min; a water inrush point grouting borehole Z1 is opened at the water inrush point in the tunnel; and three water-guiding channel treatment grouting boreholes Z2, Z3, and Z4 are respectively opened in the surrounding rock around the water inrush point in the roadway, where Z2 and Z3 are two branch holes of Z1, and Z4 is a branch hole of H1.

[0012] The distance between T1 and T2 is 10m, and the distance between T2 and T3 is 11m; the distance between H1 and H2 is 11m, the distance between H2 and H3 is 10m, the distance between H3 and H4 is 10m, and the distance between H4 and H5 is 10m; the distance between Z1 and Z2 is 50m, the distance between Z1 and Z3 is 50m, the distance between Z1 and Z4 is 50m, the distance between Z2 and Z3 is 42.26m, and the distance between Z2 and Z4 is 42.26m.

[0013] In step A, seven drilling rigs are arranged downhole: 670-1, 900-1, 900-2, 900-3, 900-4, 900-5, and 900-6. The first drilling rig is deployed in drilling rig 900-1 to construct hole T1; the second drilling rig is deployed in drilling rig 900-2 to construct hole T2; the third drilling rig is deployed in drilling rig 900-3 to construct hole T3; and the third drilling rig is deployed in drilling rig 900-6... The fourth drilling rig will construct hole H4. The fifth drilling rig will be deployed in drill hole 900-5 to construct hole H2. The sixth drilling rig will be deployed in drill hole 670-1 to construct holes H3 and H5 in sequence. After hole T1 is completed, the first drilling rig will be deployed in drill hole 900-4 to construct hole H1. After hole T3 is completed, grouting borehole Z1 for roadway water inflow point and grouting boreholes Z2, Z3 and Z4 for water diversion channel treatment will continue to be constructed in drill hole 900-3.

[0014] Drilling pits are placed near existing intermediate roadways at different elevations within the mountain. Based on the target area requirements of different boreholes, the borehole depth is matched with the horizontal displacement. The appropriate location of the drilling pits in each intermediate section is determined comprehensively based on the existing roadway development situation. This minimizes the excavation and lining volume of newly drilled pits and shortens the preparation time for sudden water inrush control. Depending on the differences in borehole depth and function, a single drilling rig can be deployed to drill multiple boreholes in one drilling pit or to drill boreholes in different drilling pits to balance the workload and improve the overall utilization of the drilling rig and drilling pits.

[0015] In the above-mentioned drilling construction process for treating sudden water inrush in underground roadways, in step C, the through-hole grouting hole is a directional through-hole, and the structure of the through-hole grouting hole is three-section;

[0016] The first section is a straight hole casing section with a diameter of Φ311mm. The straight hole casing section passes from the borehole opening through the blasted loosened layer during the drilling construction to the stable bedrock section. After drilling is completed, the borehole pipe is lowered. After the borehole pipe is lowered, it is solidified with single-liquid cement grout.

[0017] The second section is a directional guide inclined casing section with a borehole diameter of Φ215.9mm. The directional guide inclined casing section is drilled to a depth of 8-10m from the top of the water passageway, and the third section is started. After the third section borehole has penetrated the passageway, a casing with a diameter of Φ177.8×8.05mm is then installed in the directional guide inclined casing section.

[0018] The third section is a bare borehole section for tunnel penetration: the borehole diameter is Φ152.4mm; after drilling to 8-10m from the top of the water passage in the directional guide sleeve section, the Φ215.9mm drill bit is replaced with a Φ152.4mm drill bit, and drilling continues to the target area at the center of the arch of the water passage to achieve tunnel penetration;

[0019] The straight-hole casing section and the directional inclined casing section are the casing sections for the grouting holes in the through tunnel, while the bare-hole section in the through tunnel is the bare-hole section for the grouting holes in the through tunnel.

[0020] The above-mentioned drilling construction process for the underground roadway water inrush control chamber (the casing section depth of each through-tunnel grouting hole is determined according to the design trajectory length of each borehole, which is 8-10m less than the design full borehole depth) after the through-tunnel is opened, when lowering the directional guide casing section, a conical wooden guide shoe is installed at the bottom end of the first casing being lowered; the length of the conical guide shoe is 30-40cm, the bottom diameter of the lower cone of the conical guide shoe is 10-12cm, and the upper part of the conical guide shoe is inserted into the first casing 8-10cm (the conical wooden guide shoe plays a guiding role during the casing lowering process and protects the casing opening); after the casing is lowered, the lower part of the conical wooden guide shoe is inserted into the three-section through-tunnel bare hole section (this can seal the borehole opening of the through-tunnel bare hole section, prevent the cement slurry for pipe solidification from flowing into the lower roadway, and ensure the pipe solidification effect), and then single-liquid cement slurry is used to solidify the casing.

[0021] In the above-mentioned drilling construction process for treating sudden water inrush in underground roadways, in step C, the drilling fluid used during the drilling process consists of water, bentonite, heavy calcium carbonate, soda ash, broad-spectrum wall protection agent, sulfonated lignite resin, anti-collapse agent and plugging agent.

[0022] Bentonite is composed of calcium-based bentonite and sodium-based bentonite. The amount of calcium-based bentonite added is 0-3 wt% of the drilling fluid weight, and the amount of sodium-based bentonite added is 0-5 wt% of the drilling fluid weight. The amount of heavy calcium carbonate added is 0-3.5 wt% of the drilling fluid weight, the amount of soda ash added is 0-5 wt% of the bentonite weight, the amount of broad-spectrum wall protection agent added is 0-2 wt% of the drilling fluid weight, the amount of sulfonated lignite resin added is 1-2 wt% of the drilling fluid weight, the amount of anti-collapse agent added is 0.5-2 wt% of the drilling fluid weight, and the amount of plugging agent added is 0-3 wt‰ of the drilling fluid weight.

[0023] The drilling fluid used for drilling the straight-hole casing section has a specific gravity of 1.05–1.20, a viscosity of 20–30 mPa·s, a sand content of less than 1 wt%, and a water loss of 6–10 mL / 30 min; the drilling fluid used for drilling the directional casing section has a specific gravity of 1.10–1.25, a viscosity of 25–40 mPa·s, a sand content of less than 0.6 wt%, and a water loss of 6–10 mL / 30 min.

[0024] In the above-mentioned drilling construction process for the treatment of sudden water inrush in underground roadways, in step C, the main grouting hole at the water inrush point and the grouting hole for the water guiding channel both have a three-section structure;

[0025] The first section is a straight-hole casing section with a diameter of Φ311mm. The straight-hole casing section extends from the borehole opening through the blasted loosened layer during drilling to the stable bedrock section. After drilling is completed, the borehole casing is lowered, and the borehole casing is solidified with single-component cement grout after it is lowered.

[0026] The second section is a directional guide sleeve section with a borehole diameter of Φ215.9mm. The directional guide sleeve section is drilled until the borehole depth reaches the designed borehole branch point, at which point drilling stops and a Φ177.8×8.05mm second section directional guide sleeve is lowered.

[0027] The third section is a directional drilling bare hole section with a diameter of Φ152.4mm, drilled to the target area.

[0028] In the above-mentioned drilling construction process for controlling sudden water inrush in underground roadways, the drilling tools used in step C are:

[0029] The drilling tools for the straight hole casing section include: a Φ311mm drill bit, a Φ178mm drill collar, and a Φ89mm or Φ73mm drill rod.

[0030] The drilling tools for the directional guide casing section include: a Φ215.9mm drill bit, a Φ165mm screw drill bit, a Φ159mm non-magnetic drill collar, a Φ159mm drill collar, and a Φ89mm drill rod or a Φ73mm drill rod.

[0031] The drilling tools for the open borehole section include: a Φ152.4mm drill bit, a Φ127mm screw drill bit, a Φ105mm non-magnetic drill collar, a Φ105mm drill collar, a Φ89mm heavy-duty drill rod, and a Φ89mm drill rod or a Φ73mm drill rod.

[0032] In the above-mentioned drilling construction process for the treatment of sudden water inrush in underground roadways, in step C, the drilling trajectory is controlled by the mud pulse wireless drilling directional drilling technology, and the measuring instrument used is the SMWD-76S wireless drilling directional instrument.

[0033] The technical solution of the present invention achieves the following beneficial technical effects:

[0034] Unlike traditional drilling techniques, the drilling operations in this invention are all located in different sections of the mine shaft. Utilizing the drilling technology for controlling sudden water inrush in underground roadways provided by this invention, the construction precision is high, the drilling path closely follows the design trajectory, successfully bypasses roadways, and minimizes interference with formation stability. During drilling, especially in the construction of grouting holes in water-bearing roadways, this invention employs a method of first penetrating the roadway and then installing directional casing. This method solves the problem of difficulty in adjusting if the conventional method of first installing two casing sections and then drilling the third open borehole section fails to successfully penetrate the roadway. For example, if deviation occurs during the construction of the third open borehole section and the penetration cannot be achieved in one attempt, the lower borehole can be sealed and the drilling redirected for easier adjustment and correction. Furthermore, the drilling technology of this invention is highly efficient, low-cost, and provides excellent sealing effects for controlling sudden water inrush in underground roadways. Attached Figure Description

[0035] Figure 1 A schematic diagram of the initial water inflow channel in the 430-section power distribution chamber of a metal mine in an embodiment of the present invention;

[0036] Figure 2 Schematic diagram of drainage in the 430 section of a metal mine in an embodiment of the present invention;

[0037] Figure 3 Schematic diagram of the water-blocking section in an embodiment of the present invention;

[0038] Figure 4 Plan view of the target area of ​​the borehole landing point in the 430 section of a metal mine in an embodiment of the present invention;

[0039] Figure 5 A schematic diagram of the distribution of drill holes and boreholes in an embodiment of the present invention;

[0040] Figure 6 Flowchart of drilling construction process in an embodiment of the present invention;

[0041] Figure 7 A schematic diagram of the H5 borehole trajectory cross-section in an embodiment of the present invention;

[0042] Figure 8 A schematic diagram of the T1 borehole trajectory cross-section in an embodiment of the present invention;

[0043] Figure 9 A schematic diagram of the Z-series near-horizontal borehole trajectory in an embodiment of the present invention;

[0044] Figure 10 A flowchart of the wireless drilling surveying instrument in this embodiment of the invention. Detailed Implementation

[0045] The drilling and construction process for treating sudden water inrush in underground tunnels of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0046] 1. Sudden water inrush in roadways / tunnels and on-site construction conditions.

[0047] 1.1 Water inrush situation in the power distribution chamber

[0048] A water inrush occurred in the 112-line power distribution chamber of section 430 in a metal mine of a mining company after blasting. The initial flow channels of the water inrush point were mainly two roadways, such as... Figure 1 As shown, there are two tunnels: one from the power distribution chamber to the main haulage tunnel of a metal mine (430), and the other from the power distribution chamber to the blind shaft (112). The water flow velocity in the connecting tunnel of the 112 line shaft (1# tunnel) is relatively slow, while the water flow velocity in the main haulage tunnel of the metal mine (430# tunnel) is relatively fast.

[0049] According to the alleyway design data provided by the owner:

[0050] (1) Lane #2 is a 1 / 4 three-center arch with a width of 3m and a height of 3m, and a designed cross-sectional area of ​​9.15m². 2 Lane #1 also features a three-centered arch design, with a designed cross-sectional area of ​​9.15m² near the water inrush point. 2 The cross-sectional area near the shaft entrance of line 112 is 16.14 m². 2 The width of the alley is increasing, with a maximum width of 4.8m and a height of 3.5m.

[0051] (2) The area surrounding the water passageway is a complete dolomite body.

[0052] (3) The distance from the water inrush location of No. 1 roadway to the edge of the shaft of the 112 line is about 92m. No. 2 roadway is connected to the 430 main transport. The distance from the water inrush location along the roadway to the No. 5 inclined shaft of the 430 main transport of a certain metal mine is about 495m.

[0053] The total water inflow of a certain metal mine's 430 power distribution chamber and 112 vertical shaft is 1650 m³. 3 / h, that is, the stable water flow rate of the No. 2 roadway outside the 430 power distribution chamber of a certain metal mine is 1650m³. 3 / h, the designed cross-sectional area of ​​tunnel #2 is 9.15 m². 2 The average dynamic water flow velocity in the tunnel can be calculated to be 180.33 m / h (3.01 m / min, 5.01 cm / s).

[0054] After a water inrush occurred in the 112-line power distribution chamber of section 430 in a certain metal mine, the water flowed through inclined ramps, inclined shaft No. 5, and inclined shaft No. 3 into the upper sections 490 and 610. The emergency pump in the 430 emergency water tank of the metal mine directly pumped the water to the surface. After the mine added multiple drainage systems in section 610, the water level was stabilized at an elevation of 605m. A schematic diagram of the drainage system in section 430 of the metal mine is shown below. Figure 2 The straight-line distance between the No. 430 emergency water tank and the No. 430 water outlet of a certain metal mine is 567 m, and the straight-line distance from the No. 5 inclined shaft to the No. 430 water outlet of the metal mine is 378 m. The pumping rate of the emergency pump at the No. 430 emergency water tank of the metal mine is 380 m / s. 3 / h, the No. 3 inclined shaft is connected to the 430 section of a certain metal mine, at an elevation of approximately 600m, with a pumping rate of 770 m / s. 3 / h.

[0055] 1.2 Overall Design Scheme for Water Inrush Control

[0056] Based on the actual site conditions, it is inferred that the No. 1 roadway outside the power distribution chamber in section 430 of a certain metal mine is in a slow-flow state. The design is to form a water-blocking wall in the No. 1 roadway by drilling and injecting concrete, and then further seal it with grouting to form a water-blocking section. The flow velocity of the water in the No. 2 roadway is relatively fast. The design is to inject aggregate through drilling. Under the action of the water flow, the aggregate diffuses from the bottom of the hole outward, gradually filling the roadway and forming an aggregate accumulation and water-blocking wall, changing the "pipe flow" in the roadway to "seepage flow". Then, a water-blocking section is formed by grouting (see the schematic diagram of the water-blocking section). Figure 3 After completing the construction of the water-blocking section, grouting will be carried out in the area near the water inflow point of the power distribution chamber to seal the ground fissures and reduce the water convection channels.

[0057] The grouting holes for the through-tunnel are arranged in the direction of water flow in the water passage (there may be only one or more water passages outside the chamber where water suddenly surges), and the distance between two adjacent grouting holes for the through-tunnel is 10-20m; the grouting holes for the water diversion channel are distributed around the water surge point in the chamber, and the distance between two adjacent grouting holes for the water diversion channel is 30-50m, and the distance between the grouting holes for the water diversion channel and the water surge point in the chamber is 20-100m (the specific design can be based on the strata to infer the water surge channel).

[0058] In this embodiment, drilling holes are set up in the 900 and 670 sections of a metal mine. Directional drilling is used to reach the No. 1 and No. 2 roadways outside the power distribution chamber in the 430 section of the metal mine to achieve tunnel penetration. Concrete is poured into the No. 1 roadway through three tunnel penetration boreholes T1, T2, and T3, and aggregate is poured into the No. 2 roadway through five tunnel penetration boreholes H1-H5. Grouting is then used to form a water-blocking section to seal the water-passing roadway.

[0059] In the water source sealing area, directional drilling technology was used to drill from the 900-meter section to the vicinity of the water inflow point in the 430-meter section of a metal mine's power distribution chamber. Grouting was then carried out sequentially through one main borehole Z1 and three branch boreholes Z2-Z4 to seal the area surrounding the 430-meter power distribution chamber of the metal mine (see details). Figure 4 The distance between T1 and T2 is 10m, the distance between T2 and T3 is 11m; the distance between H1 and H2 is 11m, the distance between H2 and H3 is 10m, the distance between H3 and H4 is 10m, the distance between H4 and H5 is 10m; the distance between Z1 and Z2 is 51m, the distance between Z1 and Z3 is 50m, the distance between Z1 and Z4 is 46m, the distance between Z2 and Z3 is 42.26m, the distance between Z2 and Z4 is 41m, the distance from T1 to shaft 112 is 35m, and the vertical distance from Z4 to roadway #2 is 61.60m.

[0060] 1.3 Key Points and Difficulties in Construction

[0061] This embodiment requires rapid construction and effective water-blocking. The timeframe is tight, the task is demanding, and there are many challenging and difficult aspects, including:

[0062] (1) Downhole construction

[0063] The metal mining area is located in a mountainous and steep area, which does not meet the conditions for surface construction. The main work sites are all located underground, the working space is limited, and the entry and exit of equipment, underground transportation and on-site assembly are quite difficult.

[0064] (2) Equipment modification and construction efficiency

[0065] Due to limited downhole working space, large drilling equipment cannot be used, necessitating modifications to the existing equipment. This involves reducing the height of the drilling rig and the width of the rig base, increasing the amount of preparatory work. Lowering the rig height also shortens the drill pipe length, increasing tripping and tripping work and negatively impacting drilling efficiency.

[0066] (3) Around the alley

[0067] Near the designed trajectories of boreholes T1, T2, T3, and Z1, there are existing roadways in sections 760, 670, and 610. During construction, it is necessary to strictly control the borehole trajectory to ensure that the boreholes avoid each roadway by a sufficient safe distance. The T1 borehole needs to pass through a 30m space between two existing roadways in section 670, requiring high construction precision.

[0068] (4) Through alley

[0069] All eight boreholes were designed to penetrate the tunnel, with five of them having a design trajectory that intersects the tunnel at an angle. Tunnel #1 is 4.8m wide, while tunnel #2 is only 3m wide, making penetration quite challenging.

[0070] 2.1 Drilling Construction

[0071] 2.1.1 Drilling hole layout and drilling sequence

[0072] Drilling pits are strategically placed near existing intermediate roadways at different elevations underground. Based on the target area requirements of different boreholes, the borehole depth and horizontal displacement are matched. The appropriate locations for the drilling pits in each intermediate section are determined comprehensively, taking into account the existing roadway development situation. This minimizes the excavation and lining volume of newly drilled pits and shortens the preparation time for water inrush control. Depending on the differences in borehole depth and function, one drilling rig can be deployed to drill multiple holes in one pit, or drill holes can be drilled separately in different pits to balance workload and improve the overall utilization of drilling rigs and pits. Considering the project duration, site conditions, and the distribution of existing roadways in each intermediate section, it was decided to deploy 6 drilling pits in the 900 level and 1 drilling pit in the 670 level, with a total of 6 drilling rigs deployed. Figure 5 As shown, drill hole numbers starting with 900 refer to drill holes constructed in the 900 section, and drill hole numbers starting with 670 refer to drill holes constructed in the 670 section. Among them, drill hole 900-1 utilizes the existing permanent machine room chamber of shaft 112 with only minor modifications; drill holes 900-2, 900-3, 900-4, 900-5, and 900-6 are all newly constructed.

[0073] The specific boreholes drilled for each drilling site are as follows: Figure 5 As shown in the diagram. Based on the construction progress of each drill nest, the drilling sequence is as follows: First, one drilling rig is deployed in drill nest 900-1 to construct hole T1; a second drilling rig is deployed in drill nest 900-2 to construct hole T2; a third drilling rig is deployed in drill nest 900-3 to construct hole T3; a fourth drilling rig is deployed in drill nest 900-6 to construct hole H4; a fifth drilling rig is deployed in drill nest 900-5 to construct hole H2; and a sixth drilling rig is deployed in drill nest 670-1 to construct holes H3 and H5 sequentially. After hole T1 is completed, the first drilling rig is deployed in drill nest 900-4 to construct hole H1. After hole T3 is completed, grouting boreholes Z1-Z4 for the 430 water inflow point of a certain metal mine are constructed in drill nest 900-3. A schematic diagram of the borehole and drill nest distribution in this embodiment is shown in [reference needed]. Figure 5 .

[0074] Hole Z1 is the main grouting hole for the treatment of the water inrush area, and Z2 and Z3 are branch holes of hole Z1. Hole Z4 is a branch hole of hole H1. The bottom elevation of holes Z1, Z2, Z3, and Z4 is +410m; the specific bottom coordinates are described later. After the main hole is grouted, it is sealed, and then the hole is swept to a depth of 330m before branch hole drilling begins, directional drilling to the designed target area. After the first branch hole is grouted, the process of sealing the hole and starting drilling the second branch hole is repeated, and so on, until holes Z2, Z3, and Z4 are completed.

[0075] 2.1.2 Drilling Technology and Construction Process

[0076] To effectively shorten the borehole cycle, improve borehole trajectory control quality, and accelerate construction progress, this embodiment employs composite drilling technology, using mud circulation to carry rock powder in centerless drilling. Composite drilling is a drilling technology that utilizes high-efficiency drill bits, screw drilling tools, and rotary table drilling. The combination of high-efficiency drill bits and screw drilling tools significantly increases drilling speed, allowing for drilling and directional drilling without tripping or pulling in, resulting in high mechanical drilling speeds, often several times that of ordinary drilling. High-efficiency drill bits primarily consist of long-life roller cone bits and PDC bits. The screw drilling tool utilizes high-pressure mud forced downwards through a helical channel between the screw and the stator rubber bushing. Under pressure differential, this generates a working torque in the screw, driving the spindle to rotate and enabling the drill bit to operate.

[0077] The drilling process flow in this embodiment is as follows: Figure 6 As shown, the preparatory work before formal drilling includes building a mud pit, pouring a mortar base inside the drill hole, marking out the hole position, excavating water diversion and slurry drainage trenches, and installing and debugging the drilling rig. The mortar base of the drilling rig is made of concrete and must be flat and firm to prevent the drilling tower from tilting.

[0078] 2.1.3 Drilling Structure

[0079] (1) The T series and H series have 8 holes that are directional through-hole holes, and the drilling structure is designed to be divided into three sections.

[0080] The first section is a straight hole with a diameter of Φ311mm. The borehole pipe is lowered and passes through the blasted loosened layer during the drilling to the stable bedrock section. The pipe is then solidified with single-liquid cement grout (when the rock strata at the bottom of the drill hole are in good condition and the blasted loosened layer is very small, the ground loosened layer can be broken with a pneumatic pick before the borehole pipe is installed).

[0081] The second drilling section, with a borehole diameter of Φ215.9mm, stops at 8-10m above the roof of the 430 roadway in a certain metal mine (except for the H1 borehole, which will be adjusted on-site according to the construction situation), and then the third drilling section begins.

[0082] The third borehole section, with a borehole diameter of 152.4 mm, is an open borehole section, drilled to the target area of ​​the 430 target roadway in a certain metal mine. After the borehole penetration, a Φ177.8 × 8.05 mm second-stage casing was installed in the second stage. Schematic diagrams of the borehole trajectories for H5 and T1 are shown below. Figure 7 and Figure 8 .

[0083] (2) The Z series drilling structure is divided into three sections.

[0084] The first section is a straight hole with a diameter of Φ311mm. The borehole pipe is lowered and passes through the blasted loosened layer during the drilling to the stable bedrock section. The pipe is then solidified with single-liquid cement grout (when the rock strata at the bottom of the drill hole are in good condition and the blasted loosened layer is very small, the ground loosened layer can be broken with a pneumatic pick before the borehole pipe is installed).

[0085] The second section of the directional guide was opened, with a borehole diameter of Φ215.9mm. Drilling was stopped when the borehole depth reached 320m, and a Φ177.8×8.05mm casing was installed for fixing.

[0086] The three-section directional drilling section, with a borehole diameter of 152.4 mm, is a bare hole section, drilled to the designed target area. A schematic diagram of the Z-series near-horizontal drilling trajectory profile is shown below. Figure 9 .

[0087] 2.1.4 Drilling design coordinates and casing section quantities

[0088] The design starting coordinates and ending coordinates of each borehole are shown in the table below:

[0089] Table 2-1 Drilling Design Opening Coordinates and Target Base Coordinates

[0090]

[0091] 2.1.5 Drill string assembly

[0092] First stage: Φ311mm drill bit + Φ178mm drill collar + Φ89 / Φ73mm drill rod;

[0093] Second section: Φ215.9mm drill bit + Φ165mm screw drill + Φ159mm non-magnetic drill collar + Φ159mm drill collar + Φ89 / Φ73mm drill rod;

[0094] Three sections: Φ152.4mm drill bit + Φ127mm screw drill + Φ105mm drill collar + Φ89mm heavy-duty drill rod + Φ89 / Φ73mm drill rod.

[0095] In other embodiments, the drilling tool assembly can be appropriately adjusted according to the geological distribution characteristics and drilling trajectory during the construction process.

[0096] 2.1.6 Drilling fluid

[0097] This embodiment uses wireless drilling measurement-while-drilling directional composite drilling technology. Some formations require the use of special mud as drilling fluid, and the drilling fluid must have a low sand content. During the construction process, the consumption of drilling fluid must be monitored throughout, and the mud concentration and mud formula must be adjusted according to the borehole conditions.

[0098] Table 2-2 Recommended Drilling Fluid Ratios, Mud Materials, and Additive Dosages

[0099]

[0100] Drilling fluid purification employs a combination of three methods: natural sedimentation (three-stage sedimentation in mud trenches and mud pits), manual sand removal, and mechanical purification. Mechanical sand removal is the primary method, supplemented by manual sand removal and natural sedimentation, aiming to comprehensively remove unwanted solid phases from the drilling fluid, maintain and stabilize its performance, and achieve a virtuous cycle. Drilling fluid performance measuring instruments are provided to regularly measure drilling fluid properties for timely adjustments and replenishment.

[0101] 2.1.7 Casing lowering and securing

[0102] After drilling the casing section to the predetermined depth, the borehole is punched and the drill string is lifted. Before lowering the casing, the deputy technical manager briefs the grouting team leader, drilling rig operator, and other relevant construction personnel on the precautions for casing lowering and securing. During the casing lowering process, the production manager and safety officer must conduct on-site inspection and supervision. The casing lowering and securing steps are as follows:

[0103] (1) The casing specifications are Φ177.8×8.05mm modified oil casing. Check the appearance quality of the casing, check the diameter and wall thickness, check the casing thread condition, measure the length of each casing and calculate the required number of casings, and transfer the selected qualified casings to the drilling dock connection. In this embodiment, the first casing is equipped with a conical wooden guide shoe. The length of the conical guide shoe is 40cm, the bottom diameter of the cone of the lower part of the conical guide shoe is 12cm, and the upper part of the conical guide shoe is inserted into the first casing by 10cm (the conical wooden guide shoe plays a guiding role during the casing lowering process and protects the casing opening); after the casing is lowered, the lower part of the conical wooden guide shoe is inserted into the open hole section of the three-way tunnel (it can seal the borehole opening of the open hole section of the tunnel, prevent the cement slurry for casing from flowing into the lower roadway, and ensure the casing solidification effect), and then the casing is solidified with single-liquid cement slurry.

[0104] (2) Use the hanging sleeve clamp to lift and lower the sleeve one by one. The sleeves are connected by threads. Before docking, ensure that the sleeves are in a vertical state.

[0105] (3) Accurately record the number and depth of the casings. After confirming that the casings have been lowered to the predetermined depth, cut off the excess length of the casings, install the orifice cover plate, and connect the grouting pipeline.

[0106] (4) The grouting station prepares solid pipe single-liquid cement grout with a water-cement ratio of 0.6:1. The amount of salt and triethanolamine used accounts for 5‰ and 0.5‰ of the cement amount, respectively.

[0107] (5) For solid pipe grouting, a grouting pump is used to continuously inject single-liquid cement grout into the casing. After thick grout is returned from the outer edge of the casing, the grouting is stopped and then clean water is injected in a measured amount.

[0108] (6) After 12 hours of grouting, sweep out the cement slurry more than 5m from the bottom of the casing and continue curing for 24 to 36 hours. Sweep the hole to the original depth. After the water pressure test inside the casing, if there is no backflow of water outside the casing and the solidification quality requirements are met, the solidification is considered qualified. Otherwise, continue the solidification process.

[0109] The casing depths for feed holes T1, T2, and T3 are in the range of 465-470m; the casing depths for H1, H2, and H4 are in the range of 463-468m; and the casing depths for H3 and H5 are in the range of 225-230m. After drilling through the T-series and H-series boreholes, casings are lowered for concrete or aggregate feeding.

[0110] 2.1.8 Drilling trajectory control

[0111] In this embodiment, some drilling operations involve bypassing multiple roadways in multiple intermediate sections, making the construction highly challenging. Drilling trajectories must be designed according to the characteristics of each borehole and strictly controlled during construction.

[0112] To accelerate the drilling progress and improve the accuracy of borehole trajectory control in this embodiment, the drilling operation adopts composite drilling and wireless measurement-while-drilling directional drilling technology.

[0113] In actual drilling operations, a three-stage system is adopted, namely "increase-stabilize-decrease" to control the drilling trajectory.

[0114] Manual directional drilling is typically achieved using downhole power drilling tools, with screw drills being a common choice. During orientation, the angle between the working face of the screw drill tool and the borehole deflection plane is called the tool face angle. A clockwise rotation of 0–180 degrees from the borehole deflection plane is positive, and a counterclockwise rotation of 0–180 degrees is negative. The tool face azimuth is the angle obtained by adding the borehole deflection azimuth angle to the tool face angle. Orientation design is required before each directional drilling operation, primarily to determine the tool face azimuth angle and the length of the directional drilling section.

[0115] Currently, grouting boreholes commonly use combinations of mechanical gyro-based inclination and orientation instruments, wired and wireless MWD instruments, and screw drill bits for orientation. Gyro-based inclination and orientation instruments can perform measurements directly inside the casing and standard drill pipe. MWD instruments (wired or wireless) primarily use magnetic principles for azimuth measurement, requiring a strong Earth magnetic field environment. Orientation cannot be performed inside the casing or standard drill pipe; non-magnetic drill collars are required, and they are unsuitable in environments with magnetic interference.

[0116] This embodiment employs a mud pulse-type wireless measurement-while-drilling (MWD) instrument for inclination and orientation measurement. The wireless MWD instrument can perform measurements in real-time during drilling, is easy to install and operate, and does not require cable transmission of downhole data. Even without drilling, the mud pulse generator transmits data measured by the probe inside the borehole to the surface, where it is processed by a computer system to obtain real-time borehole parameters. The MWD instrument can measure the borehole dip angle, azimuth angle, and tool face angle during drilling, providing timely borehole parameters for drilling high-angle and horizontal holes. Using this instrument not only improves the accuracy of inclination and orientation measurement but also allows for real-time monitoring of orientation parameters during drilling operations, enabling timely adjustments to the orientation design. It also allows for combined sliding directional drilling and rotary drilling, increasing the mechanical drilling rate and significantly improving drilling efficiency. It effectively ensures that the borehole trajectory matches the design trajectory and effectively prevents complex downhole situations.

[0117] The SMWD-76S wireless surveying and mapping instrument consists of two parts: surface equipment and in-hole measuring instruments. The surface equipment includes: pressure sensors, main unit, driller's display, computer, and related connecting cables. The in-hole measuring instruments mainly consist of a surveying probe, main control unit, mud pulse generator, battery, and centralizer.

[0118] Wireless logging-while-drilling inclination measurement process as follows Figure 10 As shown, the process is divided into two stages: preparation and inclination measurement. The preparation stage mainly involves two tasks: ① installing the mud pulse probe and connecting it to the data acquisition decoder and computer; ② connecting and debugging the inclination measurement probe. During the wiring of the mud pulse probe, ensure the joints are secure and waterproof to prevent weak signal reception by the data acquisition instrument due to wiring problems. After the probe connection is complete, a simulator is used for debugging. After debugging, the non-magnetic drill collar can be inserted, enabling inclination measurement during drilling.

[0119] Borehole deviation control measures: During drilling, once the hole depth exceeds 50m, monitoring of the borehole trajectory should be strengthened, and the data should be promptly recorded on the borehole deviation plan. This allows for timely adjustments to drilling parameters or the implementation of corresponding directional correction measures based on the borehole deviation, ensuring strict control of the borehole trajectory for smooth tunnel passage. If the borehole deviation is severe, partial sealing and reorientation may be necessary.

[0120] 2.1.9 Final Hole Inspection and Sealing

[0121] After each feed hole has been drilled to the designed target area and the tunnel has been opened, and before each grouting hole has been drilled to the designed target area and is ready for grouting, the relevant responsible persons of the owner and the supervision unit should be notified in a timely manner to jointly conduct on-site measurement and inspection of the holes. After all feed and grouting work of a single hole has been completed, the hole should be sealed to the hole opening with single-component cement grout.

[0122] 2.2 Material Feeding and Construction

[0123] Concrete was poured through three holes in tunnel #1, and sand and gravel aggregate was poured through five holes in tunnel #2. If the water-blocking wall effect formed after concrete pouring in tunnel #1 was not ideal, sand and gravel aggregate could be poured in as needed after analyzing the site conditions.

[0124] 2.3 Grouting Construction

[0125] In this embodiment, the grouting construction is divided into grouting of the water-blocking section and grouting of the water source sealing section. The purpose, grouting materials, and grouting pressure of the two stages are different.

[0126] The grouting process during the construction of the water-blocking section is further divided into four different stages.

[0127] (1) Initial grouting: When the aggregate in the roadway has been filled and the aggregate accumulation height is still higher than the top of the roadway after repeated drilling and flushing, and the water flow in the roadway is reduced to less than 50% by the drainage calculation, the hole can be swept to the bottom of the borehole to start the initial grouting.

[0128] First, modified single-component grout is injected. If the effect of modified single-component grout injection is not obvious (the mine drainage volume does not decrease further), it is switched to cement-water glass two-component grout injection. If two-component grout injection cannot meet the requirements, special materials such as polyurethane are used for injection.

[0129] Initial grouting involves lowering the modified grouting head into the aggregate accumulation area and repeatedly injecting grout up and down until the grout returns to the orifice or the amount of grout entering the orifice decreases significantly. After the grout has initially set (6-10 hours), the orifice is swept to the lower part of the roadway and grouting is performed again.

[0130] The 670 grouting station underground uses an NBB-390 grouting pump for grouting, while the 900 grouting station on the surface uses BQ-350 or 3NB-260 grouting pumps. Depending on site conditions, simultaneous grouting of two wells or alternating grouting of multiple wells can be selected. The grouting volume per well per injection should not exceed 300m³. 3 .

[0131] The initial water-cement ratio for the modified single-component grout is 1:1, but the grout concentration can be adjusted according to the actual construction conditions. The mixing ratio of the cement-water glass two-component grout should be as follows: cement grout water-cement ratio 1:1, cement grout:water glass volume ratio designed within the range of 1:1 to 1:0.3.

[0132] (2) Filling grouting: Filling grouting is grouting carried out by using a high-flow grouting pump on the basis of initial grouting.

[0133] During the filling grouting stage, a combination of dual-liquid and single-liquid grouts is used. The downhole grouting station primarily uses the NBB-390 pump, while the surface 900 grouting station primarily uses the 3NB-260 and BQ-350 grouting pumps. The initial flow rate is selected to be no less than 200 L / min, and adjustments are made as needed based on actual conditions during the grouting process. The filling grouting construction is a critical stage where the "water-blocking section" is likely to be breached. Initially, grouting is carried out continuously for several shifts, with the principle of not increasing pressure at the borehole opening. Simultaneously, the water level changes in each water source observation well and each construction borehole must be constantly monitored and comprehensively analyzed in a timely manner. To control the grout diffusion distance and prevent excessive grout loss, methods such as high-concentration intermittent grouting and multi-hole combined interference grouting can be adopted, but the principle of not increasing pressure or slowly increasing pressure should still be adhered to. This process is repeated multiple times until the borehole reaches the bottom and the detected rock mass has the corresponding initial compressive strength (supporting the drill string), at which point the pressure-increasing grouting stage can begin. The relevant grout formula is referenced from the initial grouting stage.

[0134] (3) Pressure-boosting grouting stage. When the water inflow of the 430 main water transport tunnel is calculated to be below approximately 300 m³ / h through the drainage equipment, pressure-boosting grouting begins. Since the water-blocking capacity formed after filling and grouting is localized and easily broken down piecemeal, pressure-boosting grouting is necessary to extend the consolidation of the aggregate filling between adjacent grouting sections to both sides and connect them to form a whole.

[0135] This stage of grouting mainly uses NBB-390, BQ-350, and 3NB-260 grouting pumps. The grouting material is primarily modified single-component cement grout. The initial grouting flow rate is not less than 100 L / min, and the initial water-cement ratio is 1.25:1. If continuous injection is required for 60–80 m... 3 If the pressure does not increase after modifying the single-component cement grout, the viscosity of the grout will increase; conversely, if the pressure increases too quickly, the viscosity will decrease. The injection methods include single-hole large-volume grouting and single-hole small-volume intermittent grouting.

[0136] The grouting end criteria for this stage are: when the grouting pressure gradually increases to the design end pressure (4-5 MPa) of this stage, the grouting end flow rate decreases to 60 L / min, and the pressure stabilizes for 20-30 minutes, the grouting end criteria for this stage are met.

[0137] (4) Supplementary grouting stage: After the first three grouting stages are completed, the mine will conduct a trial drainage to increase the water level difference. Under these circumstances, modified single-liquid cement grout will continue to be injected to reinforce the small cracks and weak zones of the water inrush point or water passage, further reducing the water output.

[0138] The process flow for supplementary grouting is basically the same as that for pressurization. When the grouting flow rate at the end is no more than 60 L / min, the grouting pressure at the end is 5-6 MPa.

[0139] (5) Water source sealing grouting stage: Water source sealing grouting is the grouting that seals the fracture structure in the water inflow area after the water-blocking section has been basically formed. In this stage, grouting is mainly carried out using 3NB-260 grouting pump and BQ-350 grouting pump. Modified single-liquid cement grout is selected as the grouting material, with a water-cement ratio of 1:1. The initial grouting flow rate is not less than 200L / min. In order to allow the grout to spread to a far area, a large-volume grouting method is adopted.

[0140] The final grouting rate should not exceed 60 L / min. The grouting pressure should reach the designed final pressure (8.6 MPa to 10.75 MPa) and be stable for 20 to 30 minutes before the grouting work for this section can be completed.

[0141] If, during normal drilling, a fracture zone is encountered, or water gushing or significant mud loss occurs in the borehole, affecting normal drilling, grouting reinforcement or water-stopping should be carried out on the local strata.

[0142] 2.4 Construction Management Measures

[0143] According to the quality management system, each department and each position has its own responsibilities and jointly participates in the construction quality management.

[0144] The production manager and quality inspectors conduct daily on-site inspections and carry out special quality checks as needed, keeping written records.

[0145] The project team holds daily production meetings to promptly communicate relevant on-site situations, inspect and analyze construction quality, and jointly study and resolve various new situations and problems encountered during construction, ensuring that minor issues are resolved overnight and major problems are not escalated. Meeting minutes are also prepared.

[0146] (1) Drilling construction quality assurance measures

[0147] Before commencement of work, drilling trajectories were designed specifically for each borehole based on its specific conditions. Detailed technical briefings were conducted for each work team on site, clarifying key quality control points for the drilling process. Low-solids mud was used as the borehole flushing fluid, and the consumption and leakage of the flushing fluid were monitored and recorded promptly.

[0148] Orientation and directional drilling are key technologies for ensuring the successful completion of this project. This construction utilizes a wireless measuring-while-drilling (MWD) instrument for borehole orientation measurement. The MWD instrument encodes downhole parameters and generates pulse signals that drive solenoid valves within the pulse generator, restricting some mud flow into the drill string and generating positive mud pulses. On the surface, mud pressure sensors detect the mud pulse information from the downhole instruments and transmit it to a surface data processing system (including a host computer) for processing. The inclination angle, azimuth angle, and tool face angle data measured by the downhole instruments can be displayed on the computer and the driller's monitor.

[0149] ① Hole Inclination Monitoring

[0150] Guided by the measurement parameters of the wireless measuring-while-drilling instrument, the borehole trajectory is controlled directionally using a directional screw drill bit. When the borehole deviation exceeds the limit, the number of measuring points is increased, and a directional correction plan is developed.

[0151] ② Drilling deviation correction

[0152] According to the established correction plan, the deviation is corrected by using the angle of the bent screw to create deviation, and by using a drilling rig to measure.

[0153] The drilling construction process for controlling sudden water inrush in underground tunnel chambers using the method described in this embodiment has high construction precision. During the drilling process, the drilling path is not much different from the design trajectory, and the drilling process successfully bypasses the tunnel with minimal interference to the formation stability. The drilling construction process described in this embodiment is highly efficient, low-cost, and has a good sealing effect in controlling sudden water inrush in underground tunnels.

Claims

1. The drilling construction technology for controlling sudden water inrush in underground roadways, characterized in that, Includes the following steps: Step A: Based on the sudden water inrush situation in the tunnel and the on-site construction conditions, drill pits and chambers are arranged inside the mountain; Step B: Based on the construction conditions of the underground roadway, design the location of the underground grouting holes and determine the tunnel passage trajectory; Step C: According to the tunnel trajectory, use composite drilling technology to drill and construct grouting holes. In the process of constructing grouting holes in the water-passing tunnel, first drill through the tunnel and then install directional casing. In step B, 3 to 5 through-tunnel grouting holes are opened in water-passing tunnels with a flow velocity of less than 3 m / min; 5 to 10 through-tunnel grouting holes are opened in water-passing tunnels with a flow velocity greater than or equal to 3 m / min; one main grouting hole is opened at the water inrush point in the tunnel; and 3 to 5 water-guiding channel treatment grouting holes are opened in the surrounding rock around the water inrush point; the water-guiding channel treatment grouting holes are either the main grouting hole at the water inrush point or branch holes of the through-tunnel grouting holes. The grouting holes for material feeding in the through-tunnel are arranged along the direction of water flow in the water-passing tunnel, and the distance between two adjacent grouting holes for material feeding in the through-tunnel is 10-20m; the grouting holes for water diversion channel treatment are distributed around the sudden water inrush point in the tunnel, and the distance between two adjacent grouting holes for water diversion channel treatment is 30-50m, and the distance between the grouting holes for water diversion channel treatment and the sudden water inrush point in the tunnel is 20-100m; In step C, the through-tunnel feeding and grouting hole is a directional through-tunnel hole, and the structure of the through-tunnel feeding and grouting hole is three-section; The first section is a straight hole casing section with a diameter of Φ311mm. The straight hole casing section passes from the borehole opening through the blasted loosened layer during the drilling construction to the stable bedrock section. After drilling is completed, the borehole pipe is lowered. After the borehole pipe is lowered, it is solidified with single-liquid cement grout. The second section is a directional guide inclined casing section with a borehole diameter of Φ215.9mm. The directional guide inclined casing section is drilled to a depth of 8-10m from the top of the water passageway, and the third section is started. After the third section borehole has penetrated the passageway, a casing with a diameter of Φ177.8×8.05mm is then installed in the directional guide inclined casing section. The third section is a bare borehole section for tunnel penetration: the borehole diameter is Φ152.4mm; after drilling to 8-10m from the top of the water passage in the directional guide sleeve section, the Φ215.9mm drill bit is replaced with a Φ152.4mm drill bit, and drilling continues to the target area at the center of the arch of the water passage to achieve tunnel penetration; The straight hole casing section and the directional inclined casing section are the casing sections of the through tunnel feeding and grouting hole, and the through tunnel bare hole section is the bare hole section of the through tunnel feeding and grouting hole; In step C, both the main grouting hole at the water inflow point and the grouting hole for the water guiding channel have a three-section structure. The first section is a straight-hole casing section with a diameter of Φ311mm. The straight-hole casing section extends from the borehole opening through the blasted loosened layer during drilling to the stable bedrock section. After drilling is completed, the borehole casing is lowered, and the borehole casing is solidified with single-component cement grout after it is lowered. The second section is a directional guide sleeve section with a borehole diameter of Φ215.9mm. The directional guide sleeve section is drilled until the borehole depth reaches the designed borehole branch point, at which point drilling stops and a Φ177.8×8.05mm second section directional guide sleeve is lowered. The third section is a directional drilling bare hole section with a diameter of Φ152.4mm, drilled to the target area.

2. The drilling construction technology for controlling sudden water inrush in underground roadways according to claim 1, characterized in that, There are two water-passing tunnels outside the water inrush point, one of which has a water flow velocity of less than 3 m / min and the other has a water flow velocity of more than 3 m / min. In step B, three through-tunnel feeding and grouting holes T1, T2 and T3 are opened on the water-passing tunnel with a water flow velocity of less than 3 m / min. Five through-tunnel feeding and grouting holes H1, H2, H3, H4 and H5 are opened on the water-passing tunnel with a water flow velocity of more than or equal to 3 m / min. A water inrush point grouting borehole Z1 is opened at the water inrush point in the tunnel. Three water-guiding channel treatment grouting boreholes Z2, Z3 and Z4 are opened in the surrounding rock around the water inrush point in the tunnel. Z2 and Z3 are two branch holes of Z1 and Z4 is a branch hole of H1. The distance between T1 and T2 is 10m, and the distance between T2 and T3 is 11m; the distance between H1 and H2 is 11m, the distance between H2 and H3 is 10m, the distance between H3 and H4 is 10m, and the distance between H4 and H5 is 10m; the distance between Z1 and Z2 is 50m, the distance between Z1 and Z3 is 50m, the distance between Z1 and Z4 is 50m, the distance between Z2 and Z3 is 42.26m, and the distance between Z2 and Z4 is 42.26m. In step A, seven drilling rigs are arranged downhole: 670-1, 900-1, 900-2, 900-3, 900-4, 900-5, and 900-6. The first drilling rig is deployed in drilling rig 900-1 to construct hole T1; the second drilling rig is deployed in drilling rig 900-2 to construct hole T2; the third drilling rig is deployed in drilling rig 900-3 to construct hole T3; and the third drilling rig is deployed in drilling rig 900-6... The fourth drilling rig will construct hole H4. The fifth drilling rig will be deployed in drill nest 900-5 to construct hole H2. The sixth drilling rig will be deployed in drill nest 670-1 to construct holes H3 and H5 in sequence. After hole T1 is completed, the first drilling rig will be deployed in drill nest 900-4 to construct hole H1. After hole T3 is completed, grouting borehole Z1 for roadway water inflow point and grouting boreholes Z2, Z3 and Z4 for water diversion channel treatment will continue to be constructed in drill nest 900-3.

3. The drilling construction technology for controlling sudden water inrush in underground roadways according to claim 1, characterized in that, After the tunnel is opened, when lowering the directional guide casing section, a conical wooden guide shoe is installed at the bottom end of the first casing. The length of the conical wooden guide shoe is 30-40cm, the diameter of the bottom surface of the lower cone of the conical wooden guide shoe is 10-12cm, and the upper part of the conical wooden guide shoe is inserted into the first casing for 8-10cm. After the casing is lowered, the lower part of the conical wooden guide shoe is inserted into the open section of the three-way tunnel, and then the casing is fixed with single-liquid cement grout.

4. The drilling construction technology for controlling sudden water inrush in underground roadways according to claim 1, characterized in that, In step C, the drilling fluid used in the drilling process consists of water, bentonite, heavy calcium carbonate, soda ash, broad-spectrum wall protection agent, sulfonated lignite resin, anti-collapse agent and plugging agent. Bentonite is composed of calcium-based bentonite and sodium-based bentonite. The amount of calcium-based bentonite added is 0-3 wt% of the drilling fluid weight, and the amount of sodium-based bentonite added is 0-5 wt% of the drilling fluid weight. The amount of heavy calcium carbonate added is 0-3.5 wt% of the drilling fluid weight, the amount of soda ash added is 0-5 wt% of the bentonite weight, the amount of broad-spectrum wall protection agent added is 0-2 wt% of the drilling fluid weight, the amount of sulfonated lignite resin added is 1-2 wt% of the drilling fluid weight, the amount of anti-collapse agent added is 0.5-2 wt% of the drilling fluid weight, and the amount of plugging agent added is 0-3 wt‰ of the drilling fluid weight. The drilling fluid used for drilling the straight-hole casing section has a specific gravity of 1.05–1.20, a viscosity of 20–30 mPa·s, a sand content of less than 1 wt%, and a water loss of 6–10 mL / 30 min; the drilling fluid used for drilling the directional casing section has a specific gravity of 1.10–1.25, a viscosity of 25–40 mPa·s, a sand content of less than 0.6 wt%, and a water loss of 6–10 mL / 30 min.

5. The drilling construction technology for controlling sudden water inrush in underground roadways according to claim 1, characterized in that, In step C, the drilling tools used during drilling operations are: The drilling tools for the straight hole casing section include: a Φ311mm drill bit, a Φ178mm drill collar, and a Φ89mm or Φ73mm drill rod. The drilling tools for the directional guide casing section include: a Φ215.9mm drill bit, a Φ165mm screw drill bit, a Φ159mm non-magnetic drill collar, a Φ159mm drill collar, and a Φ89mm drill rod or a Φ73mm drill rod. The drilling tools for the open borehole section include: a Φ152.4mm drill bit, a Φ127mm screw drill bit, a Φ105mm non-magnetic drill collar, a Φ105mm drill collar, a Φ89mm heavy-duty drill rod, and a Φ89mm drill rod or a Φ73mm drill rod.

6. The drilling construction technology for controlling sudden water inrush in underground roadways according to claim 1, characterized in that, In step C, the borehole trajectory is controlled by the mud pulse wireless drilling directional drilling technology, and the measuring instrument used is the SMWD-76S wireless drilling directional instrument.

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