A soft rock tunnel lower deviation-correctable splicing pipe shed steel pipe supporting device

Abstract

The application provides a soft rock tunnel lower deviation-correcting splicing pipe shed steel pipe supporting device, which comprises a drill bit, a circular table, a first steel pipe, a second steel pipe and a third steel pipe; the bottom of the drill bit is sleeved with the circular table; the circular table is sleeved with an expansion and stretching support in the first steel pipe; the first steel pipe is detachably connected with the second steel pipe through a connecting device; the second steel pipe is detachably connected with the third steel pipe; a rotating shaft is fixedly connected at the center below the drill bit, the rotating shaft is located in the circular table, and the rotating shaft is fixedly connected with the output end of a motor in the circular table; and pressure sensors are fixedly installed around the circular table. The application solves the problems in the prior art, such as difficult deviation correction of drilling angle, easy occurrence of hole collapse, easy deviation of steel pipe, easy deformation of long pipe shed, error accumulation caused by the magnetic carbon rod deviation-correcting device, easy occurrence of dregs in the grouting hole, complicated pipe shed installation, and low construction efficiency.

Description

Technical Field

[0001] This invention belongs to the field of tunnel support construction technology, and relates to a correctable spliced ​​pipe roof steel pipe support device for soft rock tunnels. Background Technology

[0002] Nowadays, in the construction process of tunnel engineering, it is often necessary to carry out advance support for the surrounding rock of the tunnel. Currently, the method of setting up advance pipe roof is generally adopted. First, a guide wall is arranged at the position of advance pipe roof support, and positioning holes are drilled on the guide wall. After cleaning the holes, the pipe roof steel pipes are driven into the holes, and then grouting is carried out in the holes for reinforcement, so as to improve the overall stability of the pre-excavated surrounding rock.

[0003] However, when drilling for positioning holes at the pipe roof support location, the mechanical shaking of the drill rod can cause changes in the spatial position of the positioning hole, resulting in a deviation in the drilling angle. Therefore, it is necessary to have a better grasp of the drilling angle at all times during the drilling process and to correct any deviations in a timely manner to ensure the accurate guidance and positioning of the positioning hole for the advanced pipe roof.

[0004] In the construction of tunnels in some weak surrounding rock, the insufficient bearing capacity of the soft rock itself during the hole cleaning process can easily lead to hole collapse, making it difficult to drive the pipe roof in, causing obstruction midway, greatly reducing construction efficiency and increasing project costs. Moreover, due to the large resistance encountered during drilling, the drilling rig needs to consume a lot of energy, resulting in energy waste. In addition, in soft rock strata and sandy soil strata, fine sand and gravel can enter the interior of the steel pipe through the grouting holes on the sidewall, leading to grouting difficulties and the formation of ungrouted areas, affecting the stress on the steel pipe. In severe cases, fine sand and gravel or silt can block the grouting holes, resulting in the grout not forming a reinforced zone with the surrounding rock, leading to an unstable connection.

[0005] Currently, most of the steel pipes used in advanced pipe sheds are cylindrical steel pipes. When the steel pipes are driven into the surrounding rock, the smooth surface of the steel pipes makes the bond with the surrounding rock relatively weak, and they are prone to sliding and shifting in the hole.

[0006] Currently, long pipe roofs are gradually being used in some weak gravel strata or soft rock, boulders, and fractured zones. However, due to their long length, they are generally difficult to manufacture and transport. Although most long pipe roofs are currently divided into segments and assembled using threads, bolts, or welding, the joints are also weak points, which are prone to falling off or bending during the driving of the steel pipes. This makes it difficult to inject grout during the grouting process, resulting in poor support.

[0007] Currently, most pipe roof drilling correction devices utilize magnetic probes. When the magnetic probe and the centerline of the pipe roof are on the same plane, there is no deviation in the drilling direction. When they are not on the same straight line, the drilling direction deviates and needs to be corrected promptly. However, during the drilling process, the vibration of the pipe roof itself often causes the magnetic probe to sometimes be on the same straight line and sometimes deviate. The accumulation of small errors often eventually leads to drilling deviation.

[0008] Currently, pipe roof installation often involves on-site workers aligning the pipes before a mechanical device at the rear pushes them into the drilled holes. This method is prone to misalignment, leading to damage to the pipe roof and deformation of the threads used for connection at both ends, making it impossible to connect the pipes after insertion. Pipe roof installation is not only cumbersome but also results in unusable pipes, low construction efficiency, and increased project costs. Summary of the Invention

[0009] To achieve the above objectives, the present invention provides a correctable splicing pipe roof steel pipe support device for soft rock tunnels, which solves the problems existing in the prior art, such as difficulty in correcting the drilling angle of the drilling rig, easy collapse of the hole, easy deviation of the steel pipe, easy deformation of long pipe roofs, error accumulation caused by magnetic carbon rod correction devices, easy appearance of slag in the grouting hole, cumbersome pipe roof installation, and low construction efficiency.

[0010] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is a correctable splicing pipe roof steel pipe support device for soft rock tunnels, comprising a drill bit, a frustum, a first steel pipe, a second steel pipe, and a third steel pipe; wherein, the bottom of the drill bit is sleeved with the frustum; the frustum is sleeved with an expansion and tension bracket inside the first steel pipe; the first steel pipe and the second steel pipe are detachably connected by a connecting device; the second steel pipe and the third steel pipe are detachably connected; a rotating shaft is fixedly connected at the center below the drill bit, the rotating shaft is located in the frustum, and the rotating shaft is fixedly connected to the output end of a motor inside the frustum; pressure sensors are fixedly installed around the frustum.

[0011] Furthermore, the expansion and tensioning bracket includes a first connecting rod and a support rod; the support rod is located in the vertical openings on both sides of the first steel pipe; the connection between the first connecting rod and the support rod is rotatably connected by a pin; a telescopic rod is fixed in the middle of the first connecting rod; a telescopic sleeve matching the telescopic rod is sleeved on the top of the telescopic rod; a rubber washer is fixed inside the telescopic sleeve; a helical spring is placed inside the telescopic sleeve; the upper end of the helical spring is fixed to the rubber washer, and the lower end is connected to the upper end of the telescopic rod; the upper end of the support rod is hinged to the lower side of the connecting block; the center of the lower end of the connecting block is fixed to the upper end of the telescopic sleeve; the upper end of the connecting block is sleeved in a frustum; the connecting block is hydraulically controlled to extend and retract, and the first connecting rod is a telescopic structure.

[0012] Furthermore, the bottom ends of the first steel pipe and the top ends of the second steel pipe are provided with opening grooves on both sides; anti-slip pads are provided in the opening grooves; the connecting blocks of the connecting device are respectively engaged in the opening grooves of the first steel pipe and the second steel pipe.

[0013] Furthermore, the connecting device includes a connecting ring, the outer side of which is fixedly installed on the inner side of the connecting ring on the inner wall of the cylinder, and a connecting pipe is fixedly connected to it. The connecting pipe is sleeved at the joint between the first steel pipe and the second steel pipe. The second connecting rod passes through the sliding hole of the connecting ring, and one side of the upper and lower ends of the second connecting rod is fixedly connected to the inner wall of the cylinder by a spring. The other side of the second connecting rod is fixed with a connecting block, the size of which is consistent with the size of the opening groove.

[0014] Furthermore, a convex pad is fixed directly above the third steel pipe, and an arc-shaped block is provided at the bottom of the third steel pipe. The size of the opening between the arc-shaped blocks is the same as the size of the convex pad. The convex pad and the arc-shaped block are opposite magnets with magnetic properties.

[0015] Furthermore, the bottom of the second steel pipe is provided with an arc-shaped block identical to that at the bottom of the third steel pipe.

[0016] Furthermore, an annular scraper blade is fixed to the outer top of the third steel pipe. The annular scraper blade has a hollow frustum-shaped structure, with the smaller frustum facing the side where the drill bit is located and the larger frustum facing the side where the third steel pipe is located. A first cutter head and a second cutter head are fixed around the third steel pipe. The first cutter head and the second cutter head are arranged alternately on the outer wall of the third steel pipe, and the length of the second cutter head is less than the length of the first cutter head. Grouting holes are spirally distributed on the outer wall of the third steel pipe.

[0017] Furthermore, the upper part of the drill bit is a three-dimensional structure with a circular bottom surface and an arc-shaped longitudinal section; the lower part of the drill bit is a three-dimensional structure with circular top and bottom surfaces and a right-angled trapezoidal longitudinal section; the sides of the upper and lower parts are tangent to each other.

[0018] Furthermore, the upper part of the drill bit is fixed with drill teeth of different sizes, and the lower part of the drill bit is fixed with fish scale patterned plates around its perimeter.

[0019] Furthermore, it also includes an external device. The pressure sensor is connected to the external display screen of the external device wirelessly or via wired connection. The external device is also equipped with a correction angle setting screen, which has an angle dial and an angle knob on the side of the sensor. The angle knob is connected to the motor through a control circuit.

[0020] The beneficial effects of this invention are: 1. Since the device of the present invention is mainly used for soft surrounding rock and sandy surrounding rock, it avoids the use of a pointed cone drill bit and instead uses a drill bit with a larger contact area. Drill teeth are used at the head of the drill bit, which is more conducive to drilling into soft rock. Fish scale pattern is set on the side of the drill bit, which not only makes it easy to break through soil and drill sand, but also makes it more conducive to contact with soft rock, so as to more reliably and firmly bond together.

[0021] 2. The drill bit's unique design, due to the different forces on each side of the drill bit, plays a role in correcting deviation.

[0022] 3. The opening angle of the expansion and tensioning bracket is adjustable, suitable for steel pipes of different diameters, and easy to replace.

[0023] 4. By fixing the two steel pipes with a connecting device, compared with the current threaded connection, screw connection and welding, the stress at the connection is reasonable and it is not easy to bend.

[0024] 5. The pressure sensor measures the pressure on the device in real time, facilitating timely correction.

[0025] 6. The drill bit and the steel pipe rotate separately, allowing the drill bit to both correct deviation and drill.

[0026] 7. The second and third steel pipes of the present invention are spliced ​​together by convex pads and arc blocks, which facilitates disassembly and assembly, and the length of the entire support device can be adjusted according to the actual situation.

[0027] 8. The third steel pipe is equipped with a circumferentially fitted annular scraper blade. The annular scraper blade has a frustum-shaped structure to facilitate the scraping out of sand, soft mudstone, and silt. The first and second blades are set around it, which not only facilitates better drilling in soft rock, but also removes the soil around the pipe roof. Air holes are set around it to prevent soil and sand from entering the steel pipe through the air holes or clogging the air holes, which would lead to grouting failure. The external high-pressure blower can prevent the air holes from being blocked and can also remove slag, soil, etc. inside the steel pipe. At the same time, the air holes also serve as grouting holes. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the support device structure according to an embodiment of the present invention.

[0030] Figure 2This is a schematic diagram of the expansion and tensioning support structure according to an embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram of the connection device structure according to an embodiment of the present invention.

[0032] Figure 4 This is a schematic diagram of the convex pad and arc block structure according to an embodiment of the present invention.

[0033] Figure 5 This is a side view of the third steel pipe structure according to an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of an external device according to an embodiment of the present invention.

[0035] In the diagram, 1. Drill bit, 2. First steel pipe, 3. Connecting device, 4. Second steel pipe, 5. Third steel pipe, 6. Fish scale pattern, 7. Drill bit teeth, 8. Frustum, 9. Pressure sensor, 10. Shaft, 11. Motor, 12. Anti-slip pad, 13. Support rod, 14. Pointed drill bit, 15. First connecting rod, 16. Pin, 17. Telescopic rod, 18. Telescopic sleeve, 19. Helical spring, 20. Rubber washer, 21. Connecting ring, 22. Second connecting rod, 23. Connecting block, 24. Cylinder, 25. Connecting pipe, 26. Spring, 27. Connecting clip, 28. Convex pad, 29. Arc block, 30. Annular scraper, 31. First cutter head, 32. Second cutter head, 33. Grouting hole, 34. 35. Correction angle setting screen; 36. Expansion and stretching bracket; 37. External display screen; 38. Angle knob. Detailed Implementation

[0036] 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.

[0037] like Figure 1-6 As shown, the present invention provides a correctable splicing pipe roof steel pipe support device for soft rock tunnels, including a drill bit 1, a frustum 8, a first steel pipe 2, a connecting device 3, a second steel pipe 4, and a third steel pipe 5; wherein, the bottom of the drill bit 1 is sleeved with the frustum 8; the frustum 8 is sleeved with the expansion and tension bracket 35 inside the first steel pipe 2; the first steel pipe 2 and the second steel pipe 4 are detachably connected by the connecting device 3; the second steel pipe 4 and the third steel pipe 5 are detachably connected.

[0038] Furthermore, the upper part of the drill bit 1 is a three-dimensional structure with a circular bottom surface and an arc-shaped longitudinal section; the lower part of the drill bit 1 is a three-dimensional structure with circular top and bottom surfaces and a right-angled trapezoidal longitudinal section; the sides of the upper and lower parts are tangent; because the force-bearing areas on the left and right sides are different, the forces they receive are different, thus playing a role in correcting deviation. For example, when the drilling direction deviates to the left, the angle knob 37 on the side of the correction angle setting screen 34 can be rotated for adjustment. When adjusted to 270 degrees, the adjustment is stopped. At this time, the drill bit 1 will rotate. When the inclined part of the drill bit 1 rotates to the left, the rotation stops. Since the inclined area on the left side is larger than the flat area on the right side, the thrust on the left side is greater than that on the right side, thus causing the drill bit 1 to gradually drill to the right, gradually playing a role in correcting deviation.

[0039] In some embodiments, the upper part of the drill bit 1 is provided with drill teeth 7 of different sizes, which not only increases the contact area with soft soil and is more conducive to drilling, but also provides fish scale patterned blades 6 around the lower part of the drill bit 1, that is, fish scale-like blades, which are not only extremely sharp and easier to cut and drill in soft rock, but also more conducive to relatively close contact with soft rock, preventing the drill bit 1 from slipping and deviating from the drilling direction.

[0040] In some implementations, to achieve the function of sensing deviation, a hollow frustum 8 is fitted under the drill bit 1, allowing the drill bit 1 to rotate freely on the frustum 8. Multiple pressure sensors 9 are fixedly installed around the frustum 8. During normal forward drilling, the pressure of each pressure sensor 9 remains essentially constant. When the pressure value of a pressure sensor 9 in a certain direction suddenly increases, it indicates that the drill bit 1 is experiencing increased pressure from that direction, causing the drill bit 1 to deviate in the opposite direction. When the operator notices a sudden increase in the pressure sensor values ​​in a certain direction, drilling is stopped, the inclined portion of the drill bit 1 is adjusted to face the direction of the deviation, and drilling resumes, thus achieving the function of correcting deviation.

[0041] In some implementations, the pressure sensor 9 is connected to an external display screen 36 of an external device via wireless or wired means, and the external display screen 36 can display the angle of the drill bit 1 offset.

[0042] In some embodiments, a rotating shaft 10 is fixedly connected to the center of the lower part of the drill bit 1. The rotating shaft 10 is located in the frustum 8. The rotating shaft 10 is fixedly connected to the output end of the motor 11 inside the frustum 8. The motor 11 drives the rotating shaft 10, thereby driving the drill bit 1 to rotate.

[0043] Furthermore, vertical openings are provided on both sides of the first steel pipe 2 so that when the expansion and tensioning bracket 35 is installed, the support rods 13 with pointed drill bits 14 on both sides can be extended out from the vertical openings, and the pointed drill bits 14 on both sides can be used for drilling into soft rock. The pointed drill bits 14 on both sides are staggered to ensure that there are no dead angles in the drilling and that drilling is carried out in a circumferential manner. Figure 2As shown, the first connecting rod 15 and the support rod 13 of the expansion and tensioning bracket 35 are rotatably connected by a pin 16. A telescopic rod 17 is fixed in the middle of the first connecting rod 15, and a telescopic sleeve 18 matching the telescopic rod 17 is sleeved on top of the telescopic rod 17. A rubber washer 20 is fixed inside the telescopic sleeve 18 to prevent slippage during extension and contraction, making the connection more secure. A helical spring 19 is placed inside the telescopic sleeve 18. The upper end of the helical spring 19 is fixed to the rubber washer 20, and the lower end is connected to the upper end of the telescopic rod 17. The upper end of the support rod 13 is hinged to the lower side of the connecting block 23, and the center of the lower end of the connecting block 23 is fixed to the upper end of the telescopic sleeve 18. The upper end of the connecting block 23 is sleeved in the frustum 8, and the connecting block 23 and the frustum 8 can rotate freely. In this embodiment, the connecting block 23 is hydraulically controlled to extend and retract, and the first connecting rod 15 is a telescopic structure. When the connecting block 23 retracts, the helical spring 19 extends, compressing the first connecting rod 15 through the lower end of the support rod 13 hinged to the connecting block 23. When the connecting block 23 extends, the helical spring 19 and the telescopic sleeve 18 are compressed, stretching the first connecting rod 15 through the lower end of the support rod 13 hinged to the connecting block 23, thereby expanding the support rod 13. This allows the support rod 13 to slowly extend from the vertical opening. When the degree of extension and retraction of the connecting block 23 is different, the angle of expansion of the support rod 13 is also different, thus providing adaptability to pipe sheds of different sizes. When it is necessary to replace steel pipes of different diameters, simply stretch the expansion and tension bracket 35 and remove it from the original first steel pipe 2, then insert it into the new first pipe. Control the extension and retraction of the connecting block 23 so that the two support rods 13 of the expansion and tension bracket 35 are locked at the vertical opening of the first steel pipe 2 to prevent the expansion and tension bracket 35 from falling off. Then install the remaining parts.

[0044] In some embodiments, opening grooves are provided on both sides of the bottom end of the first steel pipe 2, and anti-slip pads 12 are placed inside the opening grooves. The second steel pipe 4, which is fixedly connected to the bottom end of the first steel pipe 2 by a connecting device 3, also has an opening groove of the same size at a certain distance from the top end, and anti-slip pads 12 are placed inside it; the connecting blocks 27 of the connecting device 3 are respectively engaged in the opening grooves of the first steel pipe 2 and the second steel pipe 4, and play a fixing role. In this embodiment, in order to facilitate the assembly and disassembly of the connecting device 3, all the opening grooves are set as inclined surfaces on the same side instead of vertical surfaces. Disassembly can be completed by simply rotating the connecting device 3 along the inclined surface direction, and the rotation direction is opposite to that of disassembly during installation.

[0045] In some implementations, such as Figure 3As shown, the connecting device 3 includes a connecting ring 21, the outer side of which is fixedly installed on the inner wall of the cylinder 24. A connecting pipe 25 is fixedly connected to the inner side of the connecting ring 21. The connecting pipe 25 is fitted into the joint of the two steel pipes to ensure a tight connection. A second connecting rod 22 passes through the sliding hole of the connecting ring 21 and can move left and right in the sliding hole. One side of the upper and lower ends of the second connecting rod 22 is fixedly connected to the inner wall of the cylinder 24 by a spring 26, and the other side is fixed with a connecting block 27. The connecting block 27 is large in size. The size of the connecting block 27 is basically the same as that of the opening groove, and it is mainly used to engage with the opening groove. The spring 26 set between the second connecting rod 22 and the cylinder 24 is mainly used to control the extension and retraction of the connecting block 27. When the connecting block 27 is not engaged with the opening groove, the spring 26 is compressed. By moving the connecting device 3, when the connecting block 27 engages with the opening groove, the spring 26 returns to its normal position. When the spring 26 is compressed, the connecting block 27 will be engaged inside the opening groove. When the spring 26 rebounds, the connecting block 27 is ejected. The connection setting of this embodiment not only makes the connection of the steel pipe more secure and reliable, but also makes it easier to disassemble and install the steel pipe. Compared with the current threaded connection, screw connection, and welding, the stress at the connection is reasonable and it is not easy to bend.

[0046] Furthermore, such as Figure 4 As shown, a convex pad 28 with four blades is fixed directly above the third steel pipe 5, and an arc-shaped block 29 is provided at the bottom of the third steel pipe 5. The size of the opening between the arc-shaped blocks 29 is the same as the size of the convex pad 28. When multiple third steel pipes 5 need to be spliced ​​to extend the pipe roof, the convex pad 28 is inserted into the upper third steel pipe 5 along the opening between the arc-shaped blocks 29, and then rotated to make the convex pad 28 and the arc-shaped block 29 fit tightly together. Since the convex pad 28 and the arc-shaped block 29 are opposite magnets with strong magnetism (in some embodiments, they can also be electromagnetic structures), they will be tightly connected when they are close to each other. Similarly, when splicing the next section of steel pipe, the same operation is performed to gradually splice the pipe roof to the appropriate size. The length of each section of the pipe roof should not be too long.

[0047] In some embodiments, for ease of installation, the bottom of the second steel pipe 4 is also provided with the same arc-shaped block 29 as the bottom of the third steel pipe 5, so as to facilitate the splicing of the third steel pipe 5 and the second steel pipe 4.

[0048] In some implementations, such as Figure 5As shown, an annular scraper 30 is fixed to the outer top of the third steel pipe 5. The annular scraper 30 has a hollow frustum-shaped structure, with the smaller frustum facing the side where the drill bit 1 is located and the larger frustum facing the side where the third steel pipe 5 is located, to facilitate the scraping out of sand, soft mudstone, and silt. A first cutter head 31 and a second cutter head 32 are also fixed around the third steel pipe 5. Each cutter head and the third steel pipe 5 are integrally formed, improving the overall structural strength. The first cutter head 31 and the second cutter head 32 are staggered on the outer wall of the third steel pipe 5, with the length of the second cutter head 32 being shorter than the length of the first cutter head 31. The first cutter head 31 and the second cutter head 32 can break up cemented lumps and rocks encountered in soft rock tunnels, which is also more conducive to the drilling of the third steel pipe 5. The outer wall of the third steel pipe 5 has spirally distributed air holes, which also serve as grouting holes 33. By connecting to an external high-pressure blower, air energy can penetrate the interior of the third steel pipe 5, expelling sand and slag from the air holes and removing loose gravel. When grouting is required, it also serves as a grouting point.

[0049] In some implementations, such as Figure 6 The external device also includes a correction angle setting screen 34, which has an angle dial and an angle knob 37 on the side of the sensor. The angle to be corrected can be adjusted by rotating the angle knob 37 (i.e., the position of the drill bit 1's inclined plane is adjusted by controlling the motor 11 through the control circuit). Inside the angle dial, the large dial represents degrees and the small dial represents minutes, with 60 minutes equaling 1 degree. For example, when the required correction angle is 36°42', it can be adjusted to 36° by rotating the angle knob 37, and then adjusted to 42' by slightly pressing the angle knob 37 downwards, thus achieving more precise drilling angle correction.

[0050] It should be noted that all circuit connections in this invention are conventional techniques in the field.

[0051] The working process of this invention is as follows: When drilling is required, the third steel pipe 5 of the support device of this invention is connected to an external power device. The power device drives the third steel pipe 5 to rotate, which in turn drives the second steel pipe 4 and the first steel pipe 2 to rotate. At the same time, the motor 11 inside the drill bit 1 is turned on to drive the drill bit 1 to rotate. It is necessary to ensure that the rotation direction of the drill bit 1 is consistent with the rotation direction of each steel pipe. The external pushing device applies a push to propel the entire support device forward. During the drilling process, the truncated cone 8 remains stationary. When the value of the pressure sensor 9 on one side of the pressure sensor 9 around the truncated cone 8 increases, it indicates that the drilling direction has deviated. The external display screen 36 displays the angle of the drilling deviation. At this time, the external power device and the motor 11 of the drill bit 1 are turned off, and the forward drilling stops. The position of the inclined plane of the drill bit 1 is adjusted by the angle knob 37 on the correction angle setting screen 34. After the position is adjusted, only the power device is turned on to drive each steel pipe to rotate while the drill bit 1 remains stationary. At this time, the entire support device will drill in the correct direction to achieve correction. When the correction is in place, the motor 11 of the drill bit 1 is turned on to make the drill bit 1 rotate and normal drilling begins.

[0052] During drilling, an external high-pressure blower is connected to the third steel pipe 5, allowing air to penetrate the interior of the third steel pipe 5, expelling sand and slag from the air vents and clearing loose gravel. When grouting is required, the blower is turned off, and grout is injected into the tunnel through the grouting hole 33. After the grouting is completed, the power unit and motor 11 are turned off, and drilling stops.

[0053] The various embodiments in this specification are described in a related manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A correctable spliced ​​pipe support device for soft rock tunnels, characterized in that, The system includes a drill bit (1), a frustum (8), a first steel pipe (2), a second steel pipe (4), and a third steel pipe (5); wherein the bottom of the drill bit (1) is sleeved with the frustum (8); the frustum (8) is sleeved with the expansion and tensioning bracket (35) inside the first steel pipe (2); the first steel pipe (2) and the second steel pipe (4) are detachably connected by a connecting device (3); the second steel pipe (4) and the third steel pipe (5) are detachably connected; a rotating shaft (10) is fixedly connected at the center below the drill bit (1), the rotating shaft (10) is located in the frustum (8), and the rotating shaft (10) is fixedly connected to the output end of the motor (11) inside the frustum (8); pressure sensors (9) are fixedly installed around the frustum (8); The expansion and tensioning bracket (35) includes a first connecting rod (15) and a support rod (13); the support rod (13) is located in the vertical openings on both sides of the first steel pipe (2); the connection between the first connecting rod (15) and the support rod (13) is rotatably connected by a pin (16); a telescopic rod (17) is fixed in the middle of the first connecting rod (15); a telescopic sleeve (18) matching the telescopic rod (17) is sleeved on the top of the telescopic rod (17); a rubber pad is fixed inside the telescopic sleeve (18). The telescopic sleeve (18) contains a helical spring (19), the upper end of which is fixed to the rubber washer (20), and the lower end is connected to the upper end of the telescopic rod (17); the upper end of the support rod (13) is hinged to the lower side of the connecting block (23), and the center of the lower end of the connecting block (23) is fixed to the upper end of the telescopic sleeve (18); the upper end of the connecting block (23) is fitted into the frustum (8); the connecting block (23) is telescopically controlled by hydraulic control, and the first connecting rod (15) is a telescopic structure; The upper part of the drill bit (1) is a three-dimensional structure with a circular bottom surface and an arc-shaped longitudinal section; the lower part of the drill bit (1) is a three-dimensional structure with a circular top and bottom surface and a right-angled trapezoidal longitudinal section; the sides of the upper and lower parts are tangent to each other.

2. The correctable splicing pipe support device for soft rock tunnels according to claim 1, characterized in that, Opening grooves are provided on both sides of the bottom end of the first steel pipe (2) and both sides of the top end of the second steel pipe (4); anti-slip pads (12) are provided in the opening grooves; the connecting blocks (27) of the connecting device (3) are respectively locked in the opening grooves of the first steel pipe (2) and the second steel pipe (4).

3. A correctable spliced ​​pipe support device for soft rock tunnels according to claim 1 or 2, characterized in that, The connecting device (3) includes a connecting ring (21), the outer side of which is fixedly installed on the inner wall of the cylinder (24), and the inner side of which is fixedly connected to a connecting pipe (25). The connecting pipe (25) is sleeved at the joint between the first steel pipe (2) and the second steel pipe (4). The second connecting rod (22) passes through the sliding hole of the connecting ring (21), and one side of the upper and lower ends of the second connecting rod (22) is fixedly connected to the inner wall of the cylinder (24) by a spring (26). The other side of the second connecting rod (22) is fixed with a connecting block (27), and the size of the connecting block (27) is consistent with the size of the opening groove.

4. A correctable spliced ​​pipe support device for soft rock tunnels according to claim 1, characterized in that, A convex pad (28) is fixed directly above the third steel pipe (5), and an arc block (29) is provided at the bottom of the third steel pipe (5). The size of the opening between the arc blocks (29) is the same as the size of the convex pad (28). The convex pad (28) and the arc block (29) are opposite magnets with magnetic properties.

5. A correctable spliced ​​pipe support device for soft rock tunnels according to claim 1 or 4, characterized in that, The bottom of the second steel pipe (4) is provided with an arc-shaped block (29) that is the same as the bottom of the third steel pipe (5).

6. A correctable spliced ​​pipe support device for soft rock tunnels according to claim 1, characterized in that, The top outer side of the third steel pipe (5) is fixed with an annular scraper (30). The annular scraper (30) has a hollow frustum structure, with the small frustum facing the side where the drill bit (1) is located and the large frustum facing the side where the third steel pipe (5) is located. The third steel pipe (5) is fixed with a first cutter head (31) and a second cutter head (32). The first cutter head (31) and the second cutter head (32) are arranged alternately on the outer wall of the third steel pipe (5). The length of the second cutter head (32) is less than the length of the first cutter head (31). The outer wall of the third steel pipe (5) is spirally distributed with grouting holes (33).

7. A correctable spliced ​​pipe support device for soft rock tunnels according to claim 1, characterized in that, The upper part of the drill bit (1) is fixed with drill teeth (7) of different sizes, and the lower part of the drill bit (1) is fixed with fish scale pattern (6).

8. A correctable spliced ​​pipe support device for soft rock tunnels according to claim 1, characterized in that, It also includes an external device. The pressure sensor (9) is connected to the external display screen (36) of the external device wirelessly or via wired means. The external device is also equipped with a correction angle setting screen (34). The correction angle setting screen (34) is equipped with an angle disk and an angle knob (37) is provided on the side of the sensor. The angle knob (37) is connected to the motor (11) through a control circuit.

Images