Rock burst roadway rapid excavation drilling site advanced pressure relief supporting method and device

Abstract

The application relates to the technical field of pre-pressure relief supporting, and discloses a rock burst roadway rapid tunneling drill field advanced pre-pressure relief supporting method and device, a supporting assembly is arranged at the upper end of a base assembly, a lifting assembly driven by a middle hydraulic cylinder is arranged directly above the supporting assembly, abutting assemblies are symmetrically movably connected to the top of the supporting assembly, and the top of the abutting assemblies is slidably connected with the lifting assembly; a middle arc-shaped supporting assembly is arranged on the supporting assembly and located directly above the lifting assembly, side edge arc-shaped supporting assemblies are movably connected to the bottom of the middle arc-shaped supporting assembly through supporting rolling assemblies, the side edge arc-shaped supporting assemblies are arranged on the abutting assemblies, and the bottom of the supporting rolling assemblies is rolling arranged on the abutting assemblies. The middle arc-shaped supporting assembly and the side edge arc-shaped supporting assembly can be synchronously unfolded, the supporting area of the drill field top wall is enlarged, and the supporting effect is improved. The application can be quickly folded and collected for moving to the next working position, and the drill field construction safety is obviously improved.

Description

Technical Field

[0001] This invention relates to the field of pre-decompression support technology, specifically to a method and device for advanced pre-decompression support in rapid excavation drilling sites for roadways prone to rockburst. Background Technology

[0002] Rockburst is a dynamic phenomenon characterized by severe coal and rock damage occurring in coal mine roadways or working faces. During the excavation of deep coal seams, high ground stress and engineering disturbances can easily lead to stress concentration zones and the accumulation of large amounts of elastic energy in the coal and rock mass surrounding the working face. When the accumulated energy exceeds a critical value, it may induce high-energy mine tremors or even rockburst accidents, severely restricting the safe and efficient mining of coal.

[0003] To improve the safety of tunnel excavation operations, large-diameter borehole decompression technology is commonly used. This technology releases or transfers coal stress to deeper layers, eliminating stress concentration in the excavation area. Due to its ease of operation and significant effectiveness, it has become a routine anti-rock-burst method in Chinese coal mines. However, the existing process commonly employs an alternating operation mode of "direct borehole decompression within the tunnel - tunnel excavation," resulting in temporal and spatial constraints between excavation and decompression, severely impacting tunnel excavation efficiency. Another process involves constructing a drilling site on one side of the tunnel wall to decompress the tunnel through boreholes. This requires support for the drilling site, but the stability of the decompression structure within the drilling site is insufficient, with a small base support area and weak impact resistance, making it unable to withstand the impact of surrounding rock. The overall integrity and operational flexibility of the decompression structure are insufficient, requiring individual operation of multiple components for support, ultimately still limiting tunnel excavation efficiency. To address this, we introduce a method and device for advanced pre-decompression support in the drilling site for rapid excavation of tunnels prone to rock bursts. Summary of the Invention

[0004] The purpose of this invention is to provide a method and apparatus for advance pressure relief support in rapid tunneling drilling sites for rockburst-prone roadways, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A pre-pressure relief support device for rapid excavation of roadways under rockburst includes a base assembly installed in the drilling site. A support assembly is provided at the center of the upper end of the base assembly. A lifting assembly driven by a central hydraulic cylinder is provided directly above the support assembly. Abutment assemblies are symmetrically and movably connected to the top two sides of the support assembly, and the top of the abutment assembly is slidably connected to the lifting assembly. The support assembly is provided with a central arc-shaped support assembly located directly above the lifting assembly. The bottom sides of the central arc-shaped support assembly are movably connected to the side arc-shaped support assemblies by the support rolling assemblies. The side arc-shaped support assemblies sit on the abutment assembly, and the bottom of the support rolling assembly rolls on the abutment assembly. The bottom of the abutment component is connected to the side hydraulic cylinder on the base component.

[0006] Preferably, the base assembly includes two sets of parallel base plates and an X-shaped frame fixed between the two sets of base plates.

[0007] Preferably, the central hydraulic cylinder is fixed in the middle of the upper end of the X-shaped frame; The lifting assembly includes a first piston rod disposed inside a central hydraulic cylinder and an H-shaped frame fixed after the top of the first piston rod extends out of the support assembly.

[0008] Preferably, the support assembly includes upright plates symmetrically fixed on both sides of the middle part of the base assembly, a top plate fixed between the tops of the two sets of upright plates, a diagonal brace fixed to the upper end of the base assembly at the connection between the upright plates and the top plate, and an L-shaped connecting lug fixed to the side of the top plate.

[0009] Preferably, the abutting component includes an arc-shaped abutting plate, a U-shaped connecting seat disposed on the top of the arc-shaped abutting plate, and a protruding connecting head disposed in the middle of the U-shaped connecting seat; The U-shaped connector is connected to the corresponding L-shaped connector by a first pin, and the protruding connector is slidably connected to the second pin on the lifting assembly. The second pin extends through the sliding groove on the protruding connector.

[0010] Preferably, the central arc-shaped support assembly includes two sets of limiting slide plates extending through the support assembly and a central arc-shaped support plate fixed between the upper parts of the two sets of limiting slide plates; The supporting rolling assembly includes a triangular support frame fixed on both sides of the lower end of the central arc-shaped support plate and a roller movably connected to the bottom of the triangular support frame. The roller rolls and sits in the limiting groove on the abutment assembly.

[0011] Preferably, the side hydraulic cylinder is movably connected to the mounting seat at the upper end of the base assembly, and the second piston rod at the output end of the side hydraulic cylinder is movably connected to the protrusion seat abutting the bottom of the assembly by a third pin.

[0012] Preferably, the side arc support assembly includes a side arc support plate located on top of the abutment assembly and an L-shaped connecting block fixed at the lower center of the top of the side arc support plate. The L-shaped connecting block is connected to the corresponding triangular support frame by a fourth pin.

[0013] This invention also provides a pre-decompression support method for a rapid excavation drilling site for roadways prone to rock bursts, specifically including the following steps: S1: A 40m pressure relief borehole was drilled at the tunnel face using a conventional drilling rig; S2: Tunnel excavation begins, with a permitted excavation length of 30m; S3: When the tunnel is excavated to the 10m position, a drilling site is constructed on one side of the tunnel wall, and an advanced pre-decompression support device for the rapid tunneling drilling site of rockburst roadway is used to support the drilling site to ensure structural stability. S4: Use a directional drilling rig to drill 30m axially from the drilling site toward the sidewall of the roadway, then adjust the angle to turn the borehole into the coal seam of the roadway and continue drilling to a depth of 300m; the roadway can continue to be excavated while drilling.

[0014] S5: When the tunnel excavation face is 30m away from the final position of the drilled hole, construct a drilling site on one side of the tunnel wall and repeat S4.

[0015] S6: Repeat S5 until the total length of the pressure relief borehole completely covers the entire tunnel.

[0016] Compared with the prior art, the beneficial effects of the present invention are: the present invention can simultaneously deploy the central arc-shaped support component and the side arc-shaped support component, thereby expanding the support area of ​​the drilling site top wall and improving the support effect.

[0017] This invention achieves synchronous deployment and conformity of the central arc-shaped support plate and the side arc-shaped support plate to the drilling site contour through the coordinated drive of the central hydraulic cylinder and the side hydraulic cylinder, forming an integral arc-shaped support structure. This eliminates the need for separate operation of multiple components, greatly improving operational flexibility and work efficiency.

[0018] This invention can be quickly folded and retracted for movement to the next work station, enabling continuous operation of tunneling and borehole decompression, breaking the time and space constraints of the alternating mode of "drilling decompression - tunneling", and significantly improving the efficiency of rapid tunneling and the safety of drilling site construction. Attached Figure Description

[0019] Figure 1 This is an exploded structural diagram of the overall assembly of the present invention; Figure 2 This is a three-dimensional structural diagram showing the connection between the base assembly, support assembly, and lifting assembly of the present invention. Figure 3 For the present invention Figure 2 A schematic diagram of the three-dimensional structure from another perspective; Figure 4 This is a three-dimensional structural diagram of the central arc-shaped support component of the present invention; Figure 5 This is a three-dimensional structural diagram of the abutment component of the present invention; Figure 6 For the present invention Figure 5 A schematic diagram of the three-dimensional structure from another perspective; Figure 7 This is a three-dimensional structural schematic diagram of the side arc-shaped support component of the present invention; Figure 8This is a three-dimensional structural diagram showing the connection between the lifting component, the support component, and the abutment component in the folded state of the present invention. Figure 9 This is a three-dimensional structural diagram showing the connection between the lifting component, the central arc-shaped support component, and the abutment component in the folded state of the present invention. Figure 10 This is a three-dimensional structural diagram showing the connection between the central arc-shaped support component and the side arc-shaped support component in the folded state of the present invention; Figure 11 This is a schematic diagram of the overall three-dimensional structure of the present invention after folding; Figure 12 This is a front view of the overall unfolded structure of the present invention; Figure 13 This is a three-dimensional structural diagram of the invention after it has been fully unfolded. Figure 14 This is a top view of a roadway excavated by a conventional drilling rig under pressure relief. Figure 15 This is a top view of a tunnel excavated by a directional drilling rig.

[0020] In the diagram: 1. Base assembly; 101. Base plate; 102. X-shaped frame; 103. Mounting seat; 2. Support assembly; 201. Vertical plate; 202. Diagonal brace; 203. Top plate; 204. Limiting slot; 205. L-shaped connecting ear; 3. Lifting assembly; 301. First piston rod; 302. H-shaped frame; 303. Second pin; 4. Central arc-shaped support assembly; 401. Central arc-shaped support plate; 402. Limiting slide plate; 403. Anti-detachment block; 404. Three 405. Angle support frame; 501. Roller; 502. Abutment assembly; 503. U-shaped connecting seat; 504. Protruding connecting head; 505. Sliding groove; 506. First pin; 507. Limiting groove; 608. Protruding seat; 609. Side arc-shaped support assembly; 600. Side arc-shaped support plate; 601. L-shaped connecting block; 602. Fourth pin; 7. Central hydraulic cylinder; 801. Side hydraulic cylinder; 802. Second piston rod; 803. Third pin. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example: Please see Figures 1-15 The present invention provides a technical solution: A pre-pressure relief support device for rapid tunneling of roadways under rock pressure includes a base assembly 1 installed in the drilling site. The base assembly 1 includes two sets of parallel base plates 101 and an X-shaped frame 102 fixed between the two sets of base plates 101.

[0023] The central hydraulic cylinder 7 is fixed in the middle of the upper end of the X-shaped frame 102.

[0024] The X-shaped frame 102 can enhance the overall structural stability of the base assembly 1 and prevent the device from shifting or tilting due to the impact of the surrounding rock during the support process. The two sets of base plates 101 increase the contact area with the bottom surface of the drilling site, reduce the pressure per unit area, and further improve the support reliability of the base assembly 1.

[0025] The base component 1 has a support component 2 located at the center of its upper end; The support assembly 2 includes upright plates 201 symmetrically fixed on both sides of the middle part of the base assembly 1, a top plate 203 fixed between the tops of the two sets of upright plates 201, a diagonal brace 202 fixed at the connection between the upright plates 201 and the top plate 203 and the upper end of the base assembly 1, and an L-shaped connecting ear 205 fixed on the side of the top plate 203.

[0026] A lifting assembly 3 driven by a central hydraulic cylinder 7 is provided directly above the support assembly 2. The lifting assembly 3 includes a first piston rod 301 disposed inside the central hydraulic cylinder 7 and an H-shaped frame 302 fixed after the top of the first piston rod 301 extends out of the support assembly 2.

[0027] The top of the first piston rod 301 extends out of the top plate 203 and is fixed to the middle of the lower end of the H-shaped frame 302.

[0028] The top two sides of the support component 2 are symmetrically and movably connected with the abutment component 5, and the top of the abutment component 5 is slidably connected to the lifting component 3; The abutment component 5 includes an arc-shaped abutment plate 501, a U-shaped connecting seat 502 provided at the top of the arc-shaped abutment plate 501, and a protruding connecting head 503 provided in the middle of the U-shaped connecting seat 502; The U-shaped connector 502 is connected to the corresponding L-shaped connector 205 by a first pin 505. The protruding connector 503 is slidably connected to the second pin 303 on the lifting assembly 3. The second pin 303 extends through the sliding groove 504 on the protruding connector 503.

[0029] The support component 2 is provided with a central arc-shaped support component 4 located directly above the lifting component 3; The central arc-shaped support component 4 includes two sets of limiting slide plates 402 extending through the support component 2 and a central arc-shaped support plate 401 fixed between the upper parts of the two sets of limiting slide plates 402; The lower end of the limiting slide plate 402 extends through the corresponding limiting slot 204 on the top plate 203 and is fixedly connected to an anti-detachment block 403.

[0030] The two sets of limiting slide plates 402 of the central arc-shaped support component 4 extend through the corresponding limiting slots 204 on the top plate 203. The limiting slots 204 guide the movement of the limiting slide plates 402, ensuring that the anti-detachment block 403 fixed at the lower end of the limiting slide plates 402 can prevent the limiting slide plates 402 from coming out of the limiting slots 204, thus ensuring the structural integrity of the central arc-shaped support component 4.

[0031] The bottom sides of the central arc-shaped support component 4 are movably connected to the side arc-shaped support components 6 using supporting rolling components; The rolling support assembly includes a triangular support frame 404 fixed on both sides of the lower end of the central arc-shaped support plate 401 and a roller 405 movably connected to the bottom of the triangular support frame 404. The roller 405 rolls in the limiting groove 506 on the abutment assembly 5.

[0032] The limiting groove 506 is located at the top of the connection between the arc-shaped abutment plate 501 and the protruding connector 503.

[0033] The side arc support assembly 6 includes a side arc support plate 601 located on top of the abutment assembly 5 and an L-shaped connecting block 602 fixed in the middle at the lower top of the side arc support plate 601. The L-shaped connecting block 602 is connected to the corresponding triangular support frame 404 by a fourth pin 603.

[0034] The side arc-shaped support component 6 sits on the abutment component 5 (i.e., the side arc-shaped support plate 601 sits on the top surface of the arc-shaped abutment plate 501), and the bottom of the support rolling component sits on the abutment component 5. The bottom of the abutment component 5 is connected to the side hydraulic cylinder 8 on the base component 1.

[0035] The side hydraulic cylinder 8 is movably connected to the mounting seat 103 at the upper end of the base assembly 1, and the second piston rod 801 at the output end of the side hydraulic cylinder 8 is movably connected to the protruding seat 507 abutting the bottom of the assembly 5 by a third pin 802.

[0036] Specifically, when using it: The core working logic of this pre-pressure relief support device for rapid tunneling in rockburst-prone roadways is to unfold the folded state through the coordinated action of multiple components, achieving all-round and adjustable support for the top and sides of the drilling site. At the same time, the flexibility of hydraulic drive is used to complete the support. Then, in conjunction with the directional drilling rig, axial holes are drilled from the drilling site to the roadway sidewalls, allowing the boreholes to enter the coal seam of the tunneling roadway for continued drilling, forming a pre-pressure relief of the roadway, ensuring the safe and efficient tunneling operation. The specific working process is divided into four stages: device deployment, initial support, dynamic pressure adjustment, and auxiliary pressure relief. Each component works together to complete the support and pressure relief tasks.

[0037] First, place the base assembly 1 at the designated support position within the drilling site; The central hydraulic cylinder 7 is activated, which drives the internal first piston rod 301 to retract downwards. After the top of the first piston rod 301 extends out of the support assembly 2, it is fixedly connected to the H-shaped frame 302. Therefore, the first piston rod 301 will drive the lifting assembly 3 to move downwards as a whole. When the lifting component 3 moves downward, the second pin 303 on the lifting component 3 will move along the sliding groove 504, thereby driving the entire abutment component 5 to rotate upward and open around the first pin 505 through the protruding connector 503. At this time, the rollers 405 on the central arc support component 4 will roll along the limiting groove 506, thereby causing the arc abutment plate 501 of the abutment component 5 to drive the central arc support component 4 to rise synchronously until the central arc support plate 401 of the central arc support component 4 is aligned with the center position of the top of the drilling site. Meanwhile, since the side arc support plate 601 of the side arc support component 6 is located on the arc abutment plate 501, when the arc abutment plate 501 rotates upward and opens, the side arc support plate 601 will also rotate upward and open with the fourth pin 603 as the center until the side arc support plate 601 is tightly attached to the drilling site sidewall. At this time, the side arc support plate 601 and the middle arc support plate 401 form an integral arc support plate with the same arc as the drilling site arc, and support the top and sidewall of the drilling site, realizing the pre-decompression of the top and sidewall areas of the drilling site. Subsequently, when the side hydraulic cylinder 8 is activated and the second piston rod 801 extends, it will provide further support and fixation for the abutment component 5.

[0038] During the drilling process, the support force can be dynamically adjusted by regulating the output pressure of the central hydraulic cylinder 7 and the side hydraulic cylinder 8.

[0039] When the pressure at the top of the drilling site increases, the central hydraulic cylinder 7 is controlled to further retract the first piston rod 301, increasing the support force of the central arc-shaped support plate 401 on the top of the drilling site. When the pressure on both sides of the drilling site increases, the side hydraulic cylinder 8 is controlled to further extend the second piston rod 801, pushing the abutment component 5 to further rotate, increasing the support force of the side arc-shaped support plate 601 on both sides of the drilling site. Conversely, the output pressure of the corresponding hydraulic cylinder is reduced to ensure that the support force matches the surrounding rock pressure, always maintaining an effective pre-pressure relief effect, and avoiding the collapse of the surrounding rock due to insufficient support force or the damage to the components due to excessive support force.

[0040] After the central arc-shaped support component 4 and the side arc-shaped support component 6 have completed all-round support, a directional drilling rig is used to drill a 30m axial hole from the drilling site to the roadway sidewall. Then, the angle is adjusted to turn the borehole into the coal seam of the tunnel and continue drilling to a depth of 300m. This can effectively disperse the impact pressure of the surrounding rock of the roadway, achieve pre-pressure relief, and provide a safe working space for rapid tunnel excavation.

[0041] By reversing the adjustment of the central hydraulic cylinder 7 and the side hydraulic cylinder 8, each support component is folded and reset (the specific process is as follows: when folding is required, the central hydraulic cylinder 7 is reversibly adjusted to drive the first piston rod 301 to extend upward, thereby moving the entire lifting assembly 3 upward. The second pin 303 on the lifting assembly 3 moves along the sliding groove 504 of the abutment assembly 5, pulling the abutment assembly 5 to rotate downward around the first pin 505 as the center and fold; when the abutment assembly 5 is folded, its arc-shaped abutment plate 501 drives the side arc-shaped support assembly 6 sitting on it to move synchronously, and the side arc-shaped support assembly 6 rotates downward around the fourth pin 603 as the center). The device rotates and approaches the central arc-shaped support component 4; simultaneously, the rollers 405 of the central arc-shaped support component 4 roll along the limiting groove 506 of the abutment component 5, moving downwards synchronously with the folding of the abutment component 5; the side hydraulic cylinder 8 is adjusted in the opposite direction, causing its second piston rod 801 to retract, releasing the support and fixing of the abutment component 5, and assisting the folding of the abutment component 5. Finally, all components fold and retract, completing the folding, reducing the volume, and facilitating the movement of the device to the next support position. Then, the base component 1 is moved to the next support position, and the above support process is repeated, realizing the synchronous advancement of tunnel excavation and pre-decompression support, greatly improving tunneling efficiency.

[0042] Please see Figures 14-15 The present invention also provides a pre-decompression support method for a rapid excavation drilling site for roadways prone to rock bursts, specifically including the following steps: S1: A 40m pressure relief borehole was drilled at the tunnel face using a conventional drilling rig; S2: Tunnel excavation begins, with a permitted excavation length of 30m; S3: When the tunnel is excavated to the 10m position, a drilling site is constructed on one side of the tunnel wall, and an advanced pre-decompression support device for the rapid tunneling drilling site of rockburst roadway is used to support the drilling site to ensure structural stability. S4: Use a directional drilling rig to drill 30m axially from the drilling site toward the sidewall of the roadway, then adjust the angle to turn the borehole into the coal seam of the roadway and continue drilling to a depth of 300m; the roadway can continue to be excavated while drilling.

[0043] S5: When the tunnel excavation face is 30m away from the final position of the drilled hole, construct a drilling site on one side of the tunnel wall and repeat S4.

[0044] S6: Repeat S5 until the total length of the pressure relief borehole completely covers the entire tunnel.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pre-pressure relief support device for rapid excavation drilling sites in roadways prone to rock bursts, comprising a base assembly installed within the drilling site, characterized in that: The base assembly has a support component at the center of its upper end, and a lifting component driven by a central hydraulic cylinder is located directly above the support component. The support component has abutment components symmetrically and movably connected to both sides of its top, and the top of the abutment components is slidably connected to the lifting component. The support assembly is provided with a central arc-shaped support assembly located directly above the lifting assembly. The bottom sides of the central arc-shaped support assembly are movably connected to the side arc-shaped support assemblies by the support rolling assemblies. The side arc-shaped support assemblies sit on the abutment assembly, and the bottom of the support rolling assembly rolls on the abutment assembly. The bottom of the abutment component is connected to the side hydraulic cylinder on the base component.

2. The pre-pressure relief support device for rapid tunneling in rockburst-prone roadways according to claim 1, characterized in that: The base assembly includes two sets of parallel base plates and an X-shaped frame fixed between the two sets of base plates.

3. The pre-pressure relief support device for rapid tunneling in rockburst-prone roadways according to claim 1, characterized in that: The central hydraulic cylinder is fixed in the middle of the upper end of the X-shaped frame; The lifting assembly includes a first piston rod disposed inside a central hydraulic cylinder and an H-shaped frame fixed after the top of the first piston rod extends out of the support assembly.

4. The pre-pressure relief support device for rapid tunneling in rockburst-prone roadways according to claim 1, characterized in that: The support assembly includes upright plates symmetrically fixed on both sides of the middle part of the base assembly, a top plate fixed between the tops of the two sets of upright plates, a diagonal brace fixed to the upper end of the base assembly at the connection between the upright plates and the top plate, and an L-shaped connecting lug fixed to the side of the top plate.

5. The pre-pressure relief support device for rapid tunneling in rockburst-prone roadways according to claim 4, characterized in that: The abutment assembly includes an arc-shaped abutment plate, a U-shaped connecting seat at the top of the arc-shaped abutment plate, and a protruding connecting head in the middle of the U-shaped connecting seat; The U-shaped connector is connected to the corresponding L-shaped connector by a first pin, and the protruding connector is slidably connected to the second pin on the lifting assembly. The second pin extends through the sliding groove on the protruding connector.

6. The pre-pressure relief support device for rapid tunneling in rockburst-prone roadways according to claim 1, characterized in that: The central arc-shaped support assembly includes two sets of limiting slide plates extending through the support assembly and a central arc-shaped support plate fixed between the upper parts of the two sets of limiting slide plates. The supporting rolling assembly includes a triangular support frame fixed on both sides of the lower end of the central arc-shaped support plate and a roller movably connected to the bottom of the triangular support frame. The roller rolls and sits in the limiting groove on the abutment assembly.

7. The pre-pressure relief support device for rapid tunneling in rockburst-prone roadways according to claim 1, characterized in that: The side hydraulic cylinder is movably connected to the mounting seat at the upper end of the base assembly, and the second piston rod at the output end of the side hydraulic cylinder is movably connected to the protruding seat abutting the bottom of the assembly by a third pin.

8. The pre-decompression support device for rapid tunneling in rockburst-prone roadways according to claim 6, characterized in that: The side arc support assembly includes a side arc support plate located on top of the abutment assembly and an L-shaped connecting block fixed at the lower center of the top of the side arc support plate. The L-shaped connecting block is connected to the corresponding triangular support frame by a fourth pin.

9. A pre-decompression support method based on the pre-decompression support device for rapid excavation drilling sites in rockburst roadways according to any one of claims 1-8, characterized in that: Specifically, the following steps are included: S1: A 40m pressure relief borehole was drilled at the tunnel face using a conventional drilling rig; S2: Tunnel excavation begins, with a permitted excavation length of 30m; S3: When the tunnel is excavated to the 10m position, a drilling site is constructed on one side of the tunnel wall, and an advanced pre-decompression support device for the rapid tunneling drilling site of rockburst roadway is used to support the drilling site to ensure structural stability. S4: Use a directional drilling rig to drill 30m axially from the drilling site toward the sidewall of the roadway, then adjust the angle to turn the borehole into the coal seam of the tunneling roadway and continue drilling to a depth of 300m. The roadway can continue to be excavated while drilling. S5: When the tunnel excavation face is 30m away from the final position of the drilled hole, construct a drilling site on one side of the tunnel wall and repeat S4. S6: Repeat S5 until the total length of the pressure relief borehole completely covers the entire tunnel.

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