A long auger drilling device and construction method for secant cast-in-place piles

Abstract

The present invention discloses a long spiral drilling device and construction method in the field of drilling technology, including a drill pipe and a drill bit. The drill bit is fixedly installed at the lower end of the drill pipe. The drill bit includes a central rod and an inner drill string. A tip drill is fixedly connected to the bottom of the inner drill string; the bottom end of the central rod is fixedly connected with a mounting plate. A plurality of rotating drill plates are spherically connected to the circumference of the mounting plate evenly. A connecting pull rod is spherically connected to one side of each rotating drill plate. A connecting ring is sleeved outside the central rod. The connecting pull rods are all spherically connected to the connecting ring. The connecting ring can move up and down and rotate along the central rod and drive the rotating drill plates to rotate; strengthening drills are fixedly installed on both the small side surface and the large plate surface of the rotating drill plates; a plurality of vibrating rods are installed in the middle of the inner drill string; the present invention greatly enhances the soil breaking and cutting ability of the drill bit, realizes simple hole cleaning, thereby improving the hole forming quality and being beneficial to enhancing the stability of the subsequent concrete pile foundation; it can vibrate along with the lifting of the drill pipe, greatly improving the pile foundation quality and reducing the appearance of air holes.

Description

Technical Field

[0001] The invention relates to the technical field of drilling, in particular to a long spiral drilling device for an interlocking cast-in-place pile and a construction method. Background Art

[0002] The long spiral drill is a dry drilling machine with spiral blades. When the spiral drill is working, the spiral blades on the drill bit and the drill rod cut the soil and bring the soil to the ground. The long spiral drill is used to drill holes and piles are formed while the spiral pile pipe is pulled out. There will be no problems of impermeability and hole wall collapse. As a result, since concrete is injected while the spiral pile pipe is pulled out, there is no hole cleaning and vibration process, and the scum at the bottom of the hole cannot be processed and taken out, and the quality of the bottom of the pile foundation is poor. At the same time, the air in the injected concrete cannot be discharged, and more pores will be formed when the concrete pile solidifies. Leakage is likely to occur through the pores, and the strength of the pile foundation is also affected. The existing technology often sacrifices the drilling ability of the drill bit to solve the above problems, which makes it difficult to drill holes relying on the deadweight of the drill rod, affecting the efficiency of cutting and drilling.

[0003] Based on this, the present invention designs a long spiral drilling device and a construction method for an interlocking cast-in-place pile to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a long spiral drilling device and construction method for interlocking bored piles, so as to solve the problems proposed in the above-mentioned background technology that there is no hole cleaning and vibration process, the scum at the bottom of the hole cannot be processed and taken out, the quality of the bottom of the pile foundation is poor, and at the same time the air in the injected concrete cannot be discharged, and more pores will be formed when the concrete pile solidifies, leakage is likely to occur through the pores, and the strength of the pile foundation is also affected.

[0005] To achieve the above object, the present invention provides the following technical solution: comprising a drill rod and a drill bit, the drill bit is fixedly mounted at the lower end of the drill rod, the drill bit comprises a center rod and an inner drill column, the inner drill column is located in the center rod and the two are slidably matched, and a tip drill is fixedly connected to the bottom of the inner drill column;

[0006] The bottom end of the center rod is fixedly connected to a mounting plate, and a plurality of rotating drill plates are evenly ball-connected on the circumference of the mounting plate. A connecting rod is ball-connected on one side of the rotating drill plate. A connecting ring is provided on the outer cover of the center rod, and the connecting rods are all connected to the connecting ring. The connecting ring can move up and down and rotate along the center rod and drive the rotating drill plate to rotate;

[0007] The small side surface and the large plate surface of the rotating drill plate are both fixedly installed with a reinforced drill;

[0008] A plurality of vibrating rods are installed in the middle of the inner drill string, and the vibrating rods are used to achieve vibration following the up and down movement of the inner drill string.

[0009] As a further solution of the present invention, installation grooves are evenly formed in the circumference of the installation disc, connecting balls are rotatably connected in the installation grooves, extension rods are fixedly connected to the inner side of the rotating drill plate, and the extension rods are ball-jointed with the connecting balls through ball heads.

[0010] As a further solution of the present invention, the rotating drill plate is a sector plate, the horizontal unfolded diameter of the rotating drill plate matches the outer diameter of the spiral blade outside the drill rod, a ball-jointed ring is rotatably connected to the side of the rotating drill plate, a top ball is fixedly installed at the bottom of the connecting ring, and the connecting pull rod is ball-jointed with the ball-jointed ring and the top ball respectively through the ball heads at both ends.

[0011] As a further solution of the present invention, an upper fixing ring and a lower fixing ring are sleeved outside the central rod, a reversing gear is installed between the upper fixing ring and the lower fixing ring, positioning plates are fixedly connected to the sides of the upper fixing ring and the lower fixing ring, a driving motor is fixedly installed outside the central rod, and the output end of the driving motor is fixedly connected to the upper fixing ring.

[0012] As a further solution of the present invention, a hollow motor is sleeved and installed outside the central rod, the output end of the hollow motor is fixedly connected to the connecting ring, a telescopic cylinder is installed on the top of the hollow motor, and the telescopic cylinder is installed inside the drill rod.

[0013] As a further solution of the present invention, a bottom plate is fixedly connected to the inner bottom end of the drill rod, the telescopic cylinder is installed at the bottom of the bottom plate, a plurality of guiding holes are formed in the circumference of the bottom plate, a guiding pipe is communicated with the bottom of the guiding holes, an open flare is arranged at the bottom of the drill rod, and the guiding pipe extends along the shape of the flare.

[0014] As a further solution of the present invention, an outer rotating blade matching the rotation degree of the rotating drill plate is fixedly connected to the outside of the tip drill, a positioning column is fixedly connected to the top of the tip drill, a fixing hole is formed in the bottom of the installation disc, and the positioning column is inserted into the fixing hole in a matching manner.

[0015] As a further solution of the present invention, mounting plates are arranged on both sides symmetrically at the top end of the inner drill column, driving screws are rotatably connected to both sides inside the central rod, the driving screws pass through the mounting plates and cooperate with them, and an elastic scraping ring is installed at the bottom end of the central rod.

[0016] A long spiral drilling construction method for secant bored piles includes the following steps:

[0017] S1: Lower the drill rod to the measured position through a pile driver, and the pile driver drives the drill rod to rotate and vertically drill down.

[0018] S2: Realize rotary cutting and vertically drill down through the drill bit composed of the tip drill and the rotating drill plate, and discharge the drilling slag through the spiral blade outside the drill rod until drilling down to the designed height.

[0019] S3: Rotate and move down the connecting ring, and pull and rotate the rotating drill plate through the connecting pull rod to first rotate to the vertical state of the vertical plane and then rotate to the horizontal unfolded state;

[0020] S4: By repeatedly lifting the drill pipe, the rotating drill plate can be used to compact the soil residue at the bottom of the hole;

[0021] S5: Then retract the rotating drill plate to the original state, inject superfluid concrete into the bottom of the hole through the middle of the drill pipe, lift the drill pipe while injecting the concrete, and at the same time move the inner drill string up and down, and vibrate the injected concrete with a vibrating rod until the injection is completed;

[0022] S6: Sink the woven steel reinforcement cage into the hole.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] The hole surface and spiral cutting are realized through the strengthening drills on the outer side and the inner side of the rotating drill plate, which greatly enhances the soil-breaking and cutting ability of the drill bit, and the rotating drill plate can change the inclination angle and can rotate vertically, and has a certain activity space when necessary, greatly reducing the probability of drill jamming.

[0025] The multiple fan-shaped rotating drill plates have a circular unfolded surface. At this time, by repeatedly lifting and rotating the drill pipe by the pile driver, the floating soil at the bottom of the hole can be compacted through the unfolded rotating drill plate to form a relatively dense bottom of the hole, realizing simple hole cleaning, thereby improving the hole-forming quality and facilitating the enhancement of the stability of the subsequent concrete pile foundation.

[0026] Since the vibrating rod can vibrate along with the lifting of the drill pipe, the entire concrete pile can be vibrated, thereby greatly improving the quality of the pile foundation and reducing the occurrence of air holes. Brief Description of the Drawings

[0027] Figure 1 is the overall structure schematic diagram of the present invention;

[0028] Figure 2 is the front perspective semi-sectional schematic diagram of the overall structure of the present invention;

[0029] Figure 3 is the front perspective structure schematic diagram of the drill bit part of the present invention;

[0030] Figure 4 is the top perspective structure schematic diagram of the drill bit part of the present invention;

[0031] Figure 5 is the bottom perspective structure schematic diagram of the drill bit part of the present invention;

[0032] Figure 6 is the side perspective semi-sectional structure schematic diagram of the drill bit part of the present invention;

[0033] Figure 7 Schematic diagram of the front perspective stepped section structure at the drill bit of the overall structure of the present invention;

[0034] Figure 8 Schematic diagram of the front perspective stepped section structure of the drill bit part of the present invention;

[0035] Figure 9 Schematic diagrams of the top view and front view of the drill bit in the initial state of the drill bit part of the present invention;

[0036] Figure 10 Schematic diagrams of the top view and front view of the drill bit part of the present invention in the vertically unfolded state;

[0037] Figure 11 Schematic diagrams of the top view and front view of the drill bit part of the present invention in the horizontally unfolded state;

[0038] Figure 12 Schematic diagram of the inner drill string extending out for vibration use in the present invention.

[0039] In the attached drawings, the list of components represented by each reference numeral is as follows:

[0040] 1. Drill pipe; 2. Drill bit; 3. Central rod; 4. Inner drill string; 5. Tip drill; 6. Mounting plate; 7. Rotating drill plate; 8. Connecting pull rod; 9. Connecting ring; 10. Reinforcing drill; 11. Vibrating rod; 12. Mounting groove; 13. Connecting ball; 14. Extension rod; 15. Ball joint ring; 16. Top ball; 17. Upper fixing ring; 18. Lower fixing ring; 19. Positioning plate; 20. Driving motor; 21. Reversing gear; 22. Hollow motor; 23. Telescopic cylinder; 24. Bottom plate; 25. Guide hole; 26. Guide pipe; 27. Bell mouth; 28. Outer rotating edge; 29. Positioning column; 30. Fixing hole; 31. Mounting plate; 32. Driving screw; 33. Elastic scraping ring. Detailed implementation manners

[0041] Please refer to Figures 1-12 , the working principle of the technical solution provided by the present invention is as follows:

[0042] In the initial state, the drill bit 2 is as Figure 9As shown in the retracted state; during use, the drill bit 2 in the initial state is lowered by the pile driver and rotated vertically downward for drilling. When drilling, the outer rotating blade 28 of the tip drill 5 can break the soil well, and the reinforced drill 10 on the outer and inner sides of the rotating drill plate 7 is rotated to achieve hole surface and helical cutting, greatly enhancing the soil-breaking and cutting ability of the drill bit 2. Moreover, the rotating drill plate 7 can change the inclination angle and rotate vertically, and has a certain movement space when necessary, greatly reducing the probability of drill sticking; at the same time, the reinforced drill 10 can be selectively installed according to the soil quality of the drilled hole, thereby expanding the overall applicable range of the drill pipe 1; if the reinforced drills 10 on the outer and inner sides of the rotating drill plate 7 are set to reciprocate up and down along the plate surface of the rotating drill plate 7, the drilling and cutting ability can be further improved, greatly facilitating the project progress and improving the efficiency.

[0043] After the drilling is completed, (taking the Figure 9 clockwise direction of the connecting rod 8 as an example) the connecting ring 9 is first rotated counterclockwise and appropriately lifted, thereby driving the upper end of the connecting rod 8 to rotate around the axis of the central rod 3 until the originally inclined rotating drill plate 7 is pulled to the vertical state. At this time, the inner side surface of the rotating drill plate 7 is parallel to the axis of the central rod 3, and then the connecting ring 9 is lowered. The rotating drill plate 7 is lowered and opened through the connecting rod 8 to the state as shown in Figure 10 . During this process, the rotating drill plate 7 rotates in the vertical plane, first returns to the vertical state and then rotates. In this way, the rotation resistance is the smallest, and the rotating drill plate 7 can be smoothly rotated.

[0044] Then the connecting ring 9 is rotated clockwise and lowered accordingly, and then the rotating drill plate 7 is changed to the horizontally expanded state as shown in Figure 11 . At this time, the multiple fan-shaped rotating drill plates 7 have a circular expanded surface, and the diameter of this circular expanded surface can be slightly smaller than or equal to the diameter of the outer spiral blade of the drill pipe 1. At this time, by repeatedly lifting and rotating the drill pipe 1 by the pile driver, the floating soil at the bottom of the hole can be compacted through the expanded rotating drill plate 7 to form a relatively dense bottom of the hole, achieving simple hole cleaning, thereby improving the hole-forming quality and facilitating enhancing the stability of the subsequent concrete pile foundation.

[0045] After the bottom of the hole is compacted, the connecting ring 9 is rotated counterclockwise and lifted, so that the rotating drill plate 7 returns to the state as shown in Figure 9 . Then the connecting ring 9 is lifted again, so that the inner side surface of the rotating drill plate 7 is parallel to the axis of the central rod 3. Then the connecting ring 9 is rotated clockwise and lowered. The rotating drill plate 7 is pulled by the connecting rod 8 to have a certain inclination angle, and the spiral direction of the rotating drill plate 7 is the same as that of the outer rotating blade 28. Therefore, the two cooperate to have a relatively smooth cutting and hole-forming effect.

[0046] As shown in Figure 11As shown, after that, superfluid concrete is injected through the middle of the drill pipe 1. While injecting the concrete, the drill pipe 1 is lifted by the pile driver, and it is lifted following the rise of the concrete liquid level. During this process, by connecting the vibrating rod 11 and the driving screw 32 inside the central rod 3 to rotate, the mounting plate 31 drives the inner drill string 4 to move downward. During the downward movement, the rotation speed of the driving screw 32 is relatively fast, so that the inner drill string 4 and the vibrating rod 11 are quickly sunk into the concrete, and then the driving screw 32 is driven at a slower speed, and the vibrating rod 11 is lifted slowly to achieve fast insertion and slow extraction vibration, thereby effectively removing the air in the concrete; since the vibrating rod 11 can vibrate following the lifting of the drill pipe 1, the entire concrete pile can be vibrated, thus greatly improving the quality of the pile foundation and reducing the appearance of air holes.

[0047] During the upward movement of the inner drill string 4, it needs to pass through the elastic scraping ring 33 at the bottom of the mounting plate 6, so that the concrete on the outer surface of the vibrating rod 11 can be scraped off, avoiding a large amount of concrete from entering the cavity of the central rod 3, and thus enabling the driving screw 32 to operate stably during vibration; at the same time, the terminal of the driving screw 32 can be set at a relatively upper part of the bottom of the mounting plate 6, which can effectively prevent the accumulation of concrete at the bottom from affecting the transmission; at the same time, the driving screw 32 is set at a certain distance from the inner drill string 4, which can also greatly avoid contamination during use.

[0048] Following the lifting of the drill pipe 1, grouting and vibration are achieved simultaneously, which is relatively efficient and convenient. Under the same effect, time can be saved, efficiency can be improved, and the quality of the pile foundation can be improved better.

[0049] According to the arrangement order of plain piles and steel bar piles, it is determined whether to sink the steel reinforcement cage subsequently according to the type of pile foundation. After drilling holes between two plain piles, a pile foundation with a steel bar cylinder is formed. The above steps are repeated until all pile foundations are constructed, forming an interlocking concrete pile foundation.

[0050] Specifically, in the initial state, the positioning plates 19 on the outer sides of the upper fixing ring 17 and the lower fixing ring 18 clamp the rotating drill plate 7 between them, so as to play a role in stabilizing and strengthening the rotating drill plate 7 when drilling holes by rotation, avoiding large forces on the connection part of the extension rod 14 and the connection parts at both ends of the connecting pull rod 8, thereby protecting the joint and being beneficial to the service life of the drill bit 2; and when drilling holes by rotation, most of the connecting pull rod 8 and the connecting ring 9 are located in the space below the drill pipe 1, so that the connecting pull rod 8 and the connecting ring 9 can be better protected during the drilling process.

[0051] When the rotating drill plate 7 rotates from the initial state, the upper fixed ring 17 is directly driven to rotate by the driving motor 20 first. A reversing gear 21 is engaged between the lower bottom surface of the upper fixed ring 17 and the upper top surface of the lower fixed ring 18. When the upper fixed ring 17 rotates, the lower fixed ring 18 rotates in the opposite direction at the same time, thereby driving the positioning plates 19 on the outer sides of the upper fixed ring 17 and the lower fixed ring 18 to move away from each other, thereby releasing the rotating drill plate 7 so that it can rotate.

[0052] When the rotating drill plate 7 is retracted, the rotating drill plate 7 is located Figure 10 In the state shown in Figure 10 , the narrow inner surface of the rotating drill plate 7 just aligns with the gap between the positioning plates 19 of the upper fixed ring 17 and the lower fixed ring 18, and at this time the gap is relatively large, which is also very conducive to the retraction of the rotating drill plate 7. After the rotating drill plate 7 returns to the initial state, the driving motor 20 is used to reverse the upper fixed ring 17, thereby making the positioning plates 19 of the upper fixed ring 17 and the lower fixed ring 18 approach each other, and the rotating drill plate 7 can be clamped and fixed again.

[0053] In the initial state, the positioning post 29 of the tip drill 5 is inserted into the fixing hole 30 of the mounting plate 6, and the helical force during the drilling process of the tip drill 5 can be effectively transmitted, and at the same time, the driving components of the inner drill string 4 are protected.

Claims

1. A long auger drilling device for secant bored piles, comprising a drill pipe (1) and a drill bit (2), the drill bit (2) being fixedly installed at the lower end of the drill pipe (1), characterized in that: The drill bit (2) includes a central rod (3) and an inner drill string (4). The inner drill string (4) is located inside the central rod (3) and the two are in sliding fit. A tip drill (5) is fixedly connected to the bottom of the inner drill string (4). The bottom end of the central rod (3) is fixedly connected with a mounting disc (6). A plurality of rotating drill plates (7) are evenly ball-jointed on the circumference of the mounting disc (6). A connecting pull rod (8) is ball-jointed on one side of each rotating drill plate (7). A connecting ring (9) is sleeved outside the central rod (3). The connecting pull rods (8) are all ball-jointed with the connecting ring (9). The connecting ring (9) can move up and down and rotate along the central rod (3) and drive the rotating drill plates (7) to rotate. Reinforcing drills (10) are fixedly installed on both the small side surface and the large plate surface of the rotating drill plate (7). The rotating drill plate (7) is a sector plate. The horizontal unfolded diameter of the rotating drill plate (7) matches the outer diameter of the spiral blades outside the drill pipe (1). A plurality of vibrating rods (11) are installed in the middle of the inner drill string (4). The vibrating rods (11) are used to perform vibration compaction following the up and down movement of the inner drill string (4).

2. The long auger drilling device for secant pile according to claim 1, wherein: Mounting grooves (12) are evenly formed in the circumference of the mounting disc (6). Connecting balls (13) are rotatably connected in the mounting grooves (12). An extension rod (14) is fixedly connected to the inner side of the rotating drill plate (7). The extension rod (14) is ball-jointed with the connecting ball (13) through a ball head.

3. The long spiral drilling device for secant bored piles according to claim 1, wherein: A ball-joint ring (15) is rotatably connected to the side surface of the rotating drill plate (7). A top ball (16) is fixedly installed at the bottom of the connecting ring (9). The connecting pull rod (8) is ball-jointed with the ball-joint ring (15) and the top ball (16) respectively through the ball heads at both ends.

4. A long spiral drilling device for bite cast-in-place piles according to claim 1, characterized in that: An upper fixing ring (17) and a lower fixing ring (18) are sleeved outside the central rod (3). A reversing gear (21) is installed between the upper fixing ring (17) and the lower fixing ring (18). Positioning plates (19) are fixedly connected to the side surfaces of the upper fixing ring (17) and the lower fixing ring (18). A driving motor (20) is fixedly installed outside the central rod (3). The output end of the driving motor (20) is fixedly connected to the upper fixing ring (17).

5. A long auger drilling device for secant pile, characterized in that: A hollow motor (22) is sleeved and installed outside the central rod (3). The output end of the hollow motor (22) is fixedly connected to the connecting ring (9). A telescopic cylinder (23) is installed at the top of the hollow motor (22). The telescopic cylinder (23) is installed inside the drill pipe (1).

6. The long spiral drilling device for secant bored piles according to claim 5, wherein: A bottom plate (24) is fixedly connected to the inner bottom end of the drill pipe (1). The telescopic cylinder (23) is installed at the bottom of the bottom plate (24). A plurality of guiding holes (25) are formed in the circumference of the bottom plate (24). A guiding pipe (26) communicates with the bottom of the guiding holes (25). An open flared opening (27) is provided at the bottom of the drill pipe (1). The guiding pipe (26) extends following the shape of the flared opening (27).

7. The long spiral drilling device for secant bored piles according to claim 1, characterized in that: An outer rotating blade (28) that matches the rotation degree of the rotating drill plate (7) is fixedly connected to the outside of the tip drill (5). A positioning column (29) is fixedly connected to the top of the tip drill (5). A fixing hole (30) is formed at the bottom of the mounting disc (6). The positioning column (29) is inserted into the fixing hole (30) in a matching manner.

8. The long spiral drilling device for secant bored piles according to claim 1, wherein: On both sides symmetrical to the top end of the inner drill string (4), mounting plates (31) are provided. On both sides inside the central rod (3), driving screws (32) are rotatably connected. The driving screws (32) pass through the mounting plates (31) and cooperate with them. An elastic scraping ring (33) is installed at the bottom end of the central rod (3).

9. A construction method for long spiral drilling of bite cast-in-place piles, using the drilling device described in any one of claims 1-8, characterized in that It includes the following steps: S1: Drill the drill pipe (1) at the measured position through a pile driver. The pile driver drives the drill pipe (1) to rotate and drill vertically downward; S2: The drill bit (2) composed of the tip drill (5) and the rotating drill plate (7) realizes rotary cutting and drills vertically downward. The drill cuttings are discharged through the spiral blades outside the drill pipe (1) until drilling reaches the designed depth; S3: Rotate and move down the connecting ring (9), and the rotating drill plate (7) is pulled by the connecting pull rod (8) to first rotate to the vertical state of the vertical surface and then rotate to the horizontal unfolded state; S4: By repeatedly lifting the drill pipe (1), the rotating drill plate (7) can be used to compact the soil residue at the bottom of the hole; S5: Then retract the rotating drill plate (7) to the original state. Superfluid concrete is injected into the bottom of the hole through the middle of the drill pipe (1). While injecting the concrete, the drill pipe (1) is lifted. At the same time, the inner drill string (4) is moved up and down. The injected concrete is vibrated by the vibrating rod (11) until the injection is completed; S6: Lower the woven steel reinforcement cage into the hole.

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