Large-diameter tubular pile sinking equipment for rock fill stratum and construction method

Abstract

The invention discloses large-diameter tubular pile sinking equipment for a rock block filling layer and a construction method, and belongs to the field of pile foundation engineering construction. The equipment comprises a pipe-following drilling machine, a power head of the pipe-following drilling machine can be selectively connected with a down-the-hole hammer drilling tool or a reaming pile-sinking drilling tool, and a pile casing or a pipe pile is clamped through double clamps at the top and the bottom respectively. During construction, a down-the-hole hammer drilling tool is adopted for rock breaking drilling, the steel casing is synchronously sunk to the designed depth, a temporary protection wall is formed, and the steel casing is pulled out after rock slag is backfilled; and then the drilling tool is replaced by a reaming and pile sinking drilling tool, reaming drilling is carried out in situ, and the pipe pile is sunk to the designed elevation synchronously. According to the method, a dust removal and slag discharge system is integrated to collect dust and slag discharged by drilling, a steel casing is recycled through electromagnetic vibration pile pulling pliers positioned through a sliding rail, and the pile sinking perpendicularity is controlled through a portable measuring device. According to the construction method, the problems that hole collapse, slurry leakage, deviated drilling and large concrete filling coefficient are easily caused in a block stone filling layer in a traditional process are solved, and the large-diameter tubular pile sinking construction without slurry protection wall and with low pollution is realized.

Description

Technical Field

[0001] This invention relates to the field of pile foundation construction technology, specifically to a large-diameter pipe pile driving equipment and construction method for rubble-filled soil layers. Background Technology

[0002] In foundation construction fields such as building engineering, bridge engineering, and port terminals, pile foundation construction in riprap strata has always been a technical challenge. These strata typically consist of a mixture of large, loose, unconsolidated stones, gravel, and fill soil of varying sizes and high strength, exhibiting significant heterogeneity and complexity. Traditional bored pile techniques, when applied to such strata, generally face a series of prominent problems, including difficulty in hole formation, poor borehole stability, low drilling efficiency, susceptibility to borehole deviation, and difficulty in ensuring the quality of concrete pouring.

[0003] Specifically, existing technologies for pile foundation construction in riprap fill layers have mainly explored the following methods, but all of them have significant drawbacks:

[0004] Conventional rotary drilling rigs or gyratory drilling rigs combined with mud wall protection technology are prone to leakage and hole collapse when drilling in rock-filled soil layers, resulting in failure of mud wall protection; when encountering large rocks, the drill is prone to getting stuck or deviating from its path, resulting in extremely low drilling efficiency; after the hole is formed, it is difficult to clean the sediment at the bottom of the hole, and the pile concrete is prone to quality defects such as mud inclusion and broken piles, and the discharge of mud causes environmental pollution.

[0005] Full casing follow-through (e.g., full-rotation drilling rig): This method maintains borehole stability by following the steel casing throughout the drilling process, avoiding the use of drilling mud. However, when penetrating hard rock layers, conventional drill bits wear out rapidly, resulting in slow drilling speeds. When encountering oversized rocks, they may even be unable to penetrate, leading to significant equipment wear and high construction costs.

[0006] Down-the-hole (DH) hammer pre-drilling technology: This technology utilizes a high-pressure air-driven DH hammer for rock breaking, offering high efficiency. However, after DH hammer pre-drilling, the borehole wall is still prone to collapse in loose rock formations, requiring additional wall protection measures (such as follow-up casing or grouting). Furthermore, the large amount of dust and rock debris generated during DH hammer operation is ejected with the high-pressure air, causing severe air pollution and deteriorating the working environment. While patent CN114703840A combines DH hammer with jet grouting for dust reduction and wall protection, the final product is a jet grouting pile, which is unsuitable for engineering scenarios requiring the support of large-diameter precast pipe piles or cast-in-place piles.

[0007] Vibratory pipe driving technology: This technology uses a high-power vibratory hammer to drive a steel casing into the ground. However, in deep fill layers containing large stones, the resistance to vibratory sinking is high, which can easily lead to deformation of the pipe ends, making it difficult to sink to the designed depth, and also causing significant disturbance to the surrounding soil. For example, the patent with announcement number CN113669003B uses a process of vibrating to drive the steel pipe and then following up with the casing, which is a complex process and is mainly used for drilling rather than simultaneous pile driving.

[0008] Combined process attempts: Some technical solutions attempt to combine multiple processes, such as first using a down-the-hole hammer to drill the hole, then lowering a steel casing, and finally constructing the cast-in-place pile. For example, patent CN119121897A describes the use of a down-the-hole hammer and steel casing in the construction of crushed stone piles. However, this method is cumbersome, and the resistance when pulling out the steel casing is enormous, easily leading to hole collapse or difficulty in casing recovery (as described in patent CN117051834A, which requires staged concrete pouring and jack assistance to pull out the casing). It also results in low construction efficiency and cannot achieve synchronous and precise placement of large-diameter pipe piles.

[0009] In summary, existing technologies for pile foundation construction in deep riprap fill layers often suffer from several drawbacks: focusing on wall protection (such as using full casing) results in low rock-breaking efficiency; focusing on improving rock-breaking efficiency (such as using down-the-hole hammers) leads to dust pollution and wall protection challenges; and attempts to achieve simultaneous driving of large-diameter pipe piles lack an integrated solution for precise verticality control, efficient slag removal, and convenient casing recovery. Therefore, there is an urgent need for a comprehensive construction equipment and method that integrates efficient rock breaking, simultaneous wall protection / pile driving, high-precision verticality control, environmental dust removal, and efficient casing recovery to completely solve the quality, efficiency, and environmental challenges of driving large-diameter pipe piles in deep riprap fill layers.

[0010] This invention is proposed based on the shortcomings of the prior art. Summary of the Invention

[0011] The purpose of this invention is to address the problems existing in the prior art by providing a large-diameter pipe pile driving device and construction method for riprap backfill layers.

[0012] To achieve the above objectives, the technical solution adopted by the present invention is: a large-diameter pipe pile driving equipment for rubble fill layers, including a pipe-following drilling rig, the pipe-following drilling rig is equipped with a power head, the power head is equipped with a first clamp, the bottom end of the pipe-following drilling rig is equipped with a second clamp, and the power head is selectively connected to either a down-the-hole hammer drill or a hole-reaming pile driving drill.

[0013] The down-the-hole hammer drill bit includes a compressed air drill rod mounted on the power head, a down-the-hole hammer mounted on the lower end of the compressed air drill rod, and a steel casing sleeved on the outside of the compressed air drill rod.

[0014] The borehole enlargement and pile driving drill includes a spiral drill rod installed on the power head, a borehole enlargement cutting tooth drill bit installed at the lower end of the spiral drill rod, and a pipe pile sleeved on the outside of the spiral drill rod.

[0015] The first clamp is used to selectively clamp the top end of the steel casing or the pipe pile, and the second clamp is used to correspondingly clamp the bottom end of the steel casing or the pipe pile.

[0016] Preferably, there is an annular gap between the steel casing and the compressed air drill rod, and the system further includes a dust-collecting hood installed on the top of the steel casing and covering the annular gap, and a slag discharge mechanism connected to the dust-collecting hood.

[0017] Preferably, the dust collection hood is a double-cylindrical structure with an open bottom and sealed top and sides. A water pipe assembly is installed inside the dust collection hood, and a spray head is installed on the water pipe assembly.

[0018] Preferably, the slag discharge mechanism includes a slag inlet hose connected to the dust suction hood, a slag pump installed at the end of the slag inlet hose away from the dust suction hood, and a second motor installed at the output end of the slag pump, wherein the slag pump is provided with a slag discharge port.

[0019] Preferably, it also includes a vibratory pile-pulling clamp, which includes an electromagnetic suction device that is attached to the side of the steel casing by an arc-shaped suction cup and a vibratory hammer that is slidably connected to the electromagnetic suction device.

[0020] Preferably, a pressure sensor is installed on the side of the arc-shaped suction cup that is attracted to the steel casing.

[0021] Preferably, a plurality of first levels arranged in a circular array are installed around the outer periphery of the steel casing and / or the pipe pile via elastic bands, which are connected by buttons.

[0022] Preferably, it also includes a pile control device installed on the casing drilling rig, the second clamp is installed on the pile control device, and four vertical jacks and four second levels are provided around the pile control device.

[0023] This invention also provides a method for driving large-diameter pipe piles in rubble-filled soil layers, using the large-diameter pipe pile driving equipment for rubble-filled soil layers as described in any of the above schemes, the steps of which include:

[0024] The compressed air drill rod is installed on the power head, and the steel casing is fitted onto the outer periphery of the compressed air drill rod. At the same time, the top and bottom of the steel casing are clamped by the first clamp and the second clamp respectively. The compressed air drill rod is driven by the air compressor to perform pilot rock breaking drilling. At the same time, the steel casing is driven to sink synchronously to the design depth by the first clamp. Then the steel casing is pulled out.

[0025] Remove the compressed air drill rod from the power head, install the auger drill rod on the power head, fit the pipe pile onto the outer periphery of the auger drill rod, and clamp the top and bottom ends of the pipe pile using the first clamp and the second clamp respectively;

[0026] The casing drilling rig maintains the original pile center position, and the power head drives the spiral drill rod to drive the hole-expanding cutting tooth drill bit to drill. At the same time, the casing pile is driven to sink synchronously to the design elevation through the first clamp.

[0027] Preferably, the method further includes the following step: before pulling out the steel casing, backfilling the steel casing with rock powder and stone chips.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. The large-diameter pipe pile driving equipment for this riprap fill layer adopts a pipe-following drilling rig that integrates two functions: rock breaking with down-the-hole hammer drill and pile driving with hole enlargement drill. Through a two-step process of first guiding steel casing for wall protection and then simultaneously driving the pipe pile, the technical problems of difficult hole formation, easy hole collapse, and grout leakage in riprap fill layers are effectively solved, realizing mud-free wall protection construction, which is environmentally friendly and efficient.

[0030] 2. The large-diameter pipe pile driving equipment for this riprap filling layer uses a top first clamp and a bottom second clamp to hold the steel casing and pipe pile, and a verticality measuring device to monitor its verticality, thereby controlling drilling and guidance. This achieves precise guidance and synchronous sinking of the steel casing and pipe pile during the drilling process, with high verticality control accuracy.

[0031] 3. The dust removal and slag discharge component effectively collects and remotely discharges the dust and slag generated by down-the-hole hammer rock breaking, improving the working environment and preventing slag from falling back into the hole.

[0032] 4. The dedicated vibratory pile-pulling pliers are designed with an electromagnetic suction device and an arc-shaped suction cup in conjunction with a pressure sensor, which can safely, conveniently and efficiently pull out the steel casing, solving the problem of casing recovery.

[0033] 5. The construction method for large-diameter pipe piles in this riprap fill layer adopts a two-step construction method combining "down-the-hole hammer pilot rock breaking and wall protection" and "synchronous pile driving with reaming drill bit". The first step utilizes the high-efficiency impact crushing capability of the down-the-hole hammer to penetrate the riprap, while the steel casing follows simultaneously, instantly forming a stable borehole wall, solving the core technical problems of "grout leakage, borehole collapse, and drill bit jamming" in traditional riprap layers. The second step involves reaming the borehole within the formed stable borehole wall and simultaneously driving in the permanent pipe pile, achieving high-quality and high-efficiency pile construction in deep riprap fill layers. Attached Figure Description

[0034] Figure 1 This is a front view schematic diagram of the casing drilling rig of the present invention, equipped with a compressed air drill rod and a down-the-hole hammer.

[0035] Figure 2 This is a front view schematic diagram of the casing drilling rig of the present invention, equipped with a spiral drill rod and a hole-reaming cutting bit.

[0036] Figure 3This is a front view cross-sectional structural diagram of the dust removal and slag discharge assembly of the present invention.

[0037] Figure 4 This is a top view cross-sectional structural diagram of the dust removal and slag discharge assembly of the present invention.

[0038] Figure 5 This is a front view schematic diagram of the vibration pile-pulling clamp of the present invention.

[0039] Figure 6 This is a side view cross-sectional structural diagram of the vibratory hammer of the present invention.

[0040] Figure 7 This is a side view of the vibratory pile-pulling clamp of the present invention.

[0041] Figure 8 This is a front view schematic diagram of the installation structure of the first level of the present invention.

[0042] Figure 9 This is a top view schematic diagram of the installation structure of the first level of the present invention.

[0043] Figure 10 This is a schematic diagram of the structure of the first level of the present invention mounted on an elastic band.

[0044] Figure 11 This is a schematic diagram of the connection structure between the elastic band and the button of the present invention.

[0045] Figure 12 This is a schematic diagram of the structure of the second clamp and pile control device of the present invention.

[0046] In the diagram: 1. Casing drilling rig; 11. Tracked chassis; 12. Power head; 13. Vibrator; 2. First clamp; 3. Second clamp; 31. Horizontal jack; 4. Down-the-hole hammer drill bit; 41. Air-compressed drill rod; 42. Down-the-hole hammer; 43. Steel casing; 5. Reaming and pile driving drill bit; 51. Spiral drill rod; 52. Reaming cutting bit; 53. Pipe pile; 6. Dust removal and slag discharge assembly; 61. Dust suction hood; 62. Water pipe assembly; 63. Spray head; 64. Slag inlet hose; 65. Slag pump; 651. Slag discharge port; 66. Second motor; 67. Threaded steel pipe; 68. Dust cover; 69. Water inlet pipe; 7 71. Vibratory pile puller; 71. Electromagnetic lifting device; 71. Arc suction cup; 71. Concave slide rail; 71. T-shaped slide rail; 71. Limit pin; 71. Nut; 72. Vibratory hammer; 72. Cam; 72. Hammer head; 72. Guide frame; 72. Spring; 72. Hammer body; 726. Hammer shell; 727. First motor; 728. Lifting lug; 73. Pressure sensor; 74. Reading device; 8. Verticality measuring device; 81. First level; 82. Rubber seat; 83. Elastic band; 84. Button; 85. Pile control device; 86. Vertical jack; 87. Second level. Detailed Implementation

[0047] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely 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.

[0048] Please refer to Figures 1 to 12 This scheme describes a large-diameter pipe pile driving device for riprap backfill layers, including a casing drilling rig 1. The casing drilling rig 1 has a tracked chassis 11 for movement at the bottom and a power head 12 at the top to provide drilling power. The power head 12 is equipped with a first clamp 2 for clamping the top of the steel casing 43 or pipe pile 53 during construction. A pile control device 85 is located at the bottom of the casing drilling rig 1. Four vertical jacks 86 are located around the pile control device 85. A second level 87 is located near the vertical jacks 86. By adjusting the height of the vertical jacks 86, the four level bubbles of the second level 87 are centered, and the pile control device 85 is kept horizontal. A second clamp 3 is installed on the pile control device 85. The opening and closing of the second clamp 3 is controlled by a horizontal jack 31. The second clamp 3 is used to clamp the bottom of the steel casing 43 or pipe pile 53, serving as a positioning and initial guide. A vibrator 13 is mounted above the power head 12. The vibrator 13 is used to compact the soil at the bottom of the pile or to make the pile tip in close contact with the bedrock during the final stage of pile driving.

[0049] The casing drilling rig 1 is equipped with two sets of functional drilling tools, which can be quickly changed according to the construction stage.

[0050] Please refer to Figure 1 The first set is a down-the-hole hammer drill bit 4, used for pilot rock breaking and sinking temporary wall protection structures. It includes: a compressed air drill rod 41, the upper end of which is connected to a power head 12 and an external air compressor; a down-the-hole hammer 42, connected to the lower end of the compressed air drill rod 41, which relies on compressed air to impact and break the rock; and a steel casing 43, which is fitted over the outside of the compressed air drill rod 41. A sleeve with a cutting edge can be installed at the bottom end of the steel casing 43, forming an annular gap between the compressed air drill rod 41 and the inner wall of the steel casing 43.

[0051] Please refer to Figure 2 The second set is a borehole enlargement and pile driving drill tool 5, which is used for borehole enlargement drilling and synchronous pile driving. It includes a spiral drill rod 51 installed on the power head 12, a borehole enlargement cutting tooth drill bit 52 installed at the lower end of the spiral drill rod 51, and a pipe pile 53 sleeved on the outside of the spiral drill rod 51. A pile shoe with a cutting edge can be installed at the bottom end of the pipe pile 53.

[0052] Both the boot and the pile shoe are open-type structures, and both have the function of cutting and collecting excavated soil.

[0053] Please refer to Figure 1 , Figure 3 and Figure 4 To handle the large amount of dust and slag generated by the down-the-hole hammer 42 rock breaking, the equipment is equipped with a dust removal and slag discharge assembly 6. The core of this assembly is a dust suction hood 61, which is installed on the top of the steel casing 43, covering the annular gap. The dust suction hood 61 is a double-cylinder structure with an open bottom and sealed top and sides. Inside, at the top, is a water pipe assembly 62, which includes two concentric annular pipes. The outer annular pipe has a branch pipe extending towards the center and connecting to the inner annular pipe. Both the annular pipe and the branch pipe are equipped with multiple spray heads 63, which are used to spray water to suppress dust. The water pipe assembly 62 is supplied with water through a water inlet pipe 69.

[0054] Please refer to Figure 1 The side outlet of the dust suction hood 61 is connected to the slag pump 65 through the slag inlet hose 64. The slag pump 65 is driven by the second motor 66. Its inlet is connected to the slag inlet hose 64 through the threaded steel pipe 67. Its slag discharge port 651 is used to discharge slag. A dust cover 68 is provided between the slag pump 65 and the second motor 66. The dust cover 68 is used to prevent dust from damaging the second motor 66 during construction.

[0055] Please refer to Figures 5 to 7 To extract the steel casing 43 after completing the pilot hole, the equipment is equipped with a vibratory pile extractor 7. The vibratory pile extractor 7 is mainly composed of an electromagnetic suction device 71 and a vibratory hammer 72 connected by a sliding connector. The working surface of the electromagnetic suction device 71 is provided with an arc-shaped suction cup 711, the curvature of which matches the outer wall of the steel casing 43. A pressure sensor 73 is installed on the side of the arc-shaped suction cup 711 that is attracted to the steel casing 43. The pressure sensor 73 is connected to a reader 74 via a data line for real-time detection of the adsorption pressure. The vibratory hammer 72 includes a hammer shell 726, inside which is installed a cam 721 driven by a first motor 727. The cam 721 is used to drive the hammer head 722 to perform high-frequency reciprocating motion along the guide frame 723. The vibration force is transmitted through the hammer body 725 and the spring 724. The vibratory hammer 72 is equipped with a lifting lug 728 on the top for connecting to a crane. The electromagnetic suction lifting device 71 is connected to the T-shaped slide rail 713 at the bottom of the hammer shell 726 through the concave slide rail 712, which can realize horizontal sliding adjustment to adapt to steel casings 43 of different diameters. The concave slide rail 712 and the T-shaped slide rail 713 are finally locked and fixed by the limit pin 714 and the nut 715.

[0056] Specifically, the pressure sensor 73 monitors the compressive stress f (N / mm) generated by the arc-shaped suction cup 711 on the steel casing 43. 2 The area of ​​the arc-shaped suction cup 711 is S (mm²). 2The vertical pulling force generated by the arc suction cup 711 is F=μfS (N), where μ is the surface friction coefficient of the arc suction cup 711. Before pulling out the steel casing 43, the required pile pulling force Q is calculated. When 2F≥Q, the steel casing 43 can be pulled out.

[0057] Please refer to Figure 8 and Figure 12 To precisely control the verticality of the steel casing 43 and the pipe pile 53, a verticality measuring device 8 is provided on the steel casing 43 and the pipe pile 53. The device includes an elastic band 83 surrounding the steel casing 43 and the pipe pile 53. At one end of the elastic band 83 away from the steel casing 43 and the pipe pile 53, there are multiple first levels 81 connected by rubber seats 82. The multiple first levels 81 are arranged in a circular array. The number of first levels 81 is preferably three. At both ends of the elastic band 83, there are buttons 84 for fastening the elastic band 83. It can be quickly tied and fixed at a height of 1.0-1.5 meters above the ground. By tightening and loosening the wire rope of the crawler crane, the posture of the steel casing 43 or the pipe pile 53 can be adjusted. When the level bubble on the three first levels 81 is centered, the steel casing 43 and the pipe pile 53 have been kept vertical.

[0058] This invention also provides a method for driving large-diameter pipe piles in riprap fill layers, using a large-diameter pipe pile driving device for riprap fill layers as described in any of the above schemes, and the specific implementation steps include:

[0059] Part 1: Construction of Down-the-Hole Hammer 42 Pilot Hole and Steel Casing 43

[0060] S1. Pile location measurement and positioning: Real-time dynamic carrier phase differential technology (RTK) is used to measure the plane coordinates and pile top elevation of the pile location;

[0061] S2. Leveling the pile controller 85: Move the casing drilling rig 1 to the pile position, use the crawler crane to lift the second clamp 3 and the pile controller 85 to the pile position, adjust the four vertical jacks 86, observe the corresponding four second levels 87, until all the leveling bubbles are centered, at this time the pile controller 85 is leveled, and the four vertical jacks 86 are locked.

[0062] S3, Steel casing 43 in place: Use a crawler crane to lift the steel casing 43, place it vertically into the clamping range of the second clamp 3 and clamp it with the second clamp 3;

[0063] S4, Verticality correction of steel casing 43: Adjust the crane wire rope so that all the bubbles of the multiple first level instruments 81 are in the center.

[0064] S5. Connecting the drilling tools: Use a crawler crane to lift the assembled down-the-hole hammer 42 and the air-pressure drill rod 41 into the steel casing 43, and connect the top of the air-pressure drill rod 41 to the power head 12. Install the dust suction hood 61 on the top of the steel casing 43. Clamp the top of the steel casing 43 with the first clamp 2.

[0065] S6. Down-the-hole hammer 42 rock breaking drilling: Start the air compressor to drive the down-the-hole hammer 42 to impact and break the rock. At the same time, start the spray head 63 and the muck pump 65. The broken rock dust is blown into the annular gap by compressed air. Under the action of compressed air, the rock dust rises into the dust suction hood 61. After dust suppression, it is sucked into the muck pump 65 and finally discharged through the muck discharge port 651. During the drilling process, the power head 12 drives the steel casing 43 to sink synchronously through the first clamp 2. The second clamp 3 is appropriately loosened and no longer clamps the steel casing 43, only serving a guiding function.

[0066] S7. Lift out the air-pressure drill rod 41 and down-the-hole hammer 42: After drilling to the designed depth, stop drilling. Loosen the first clamp 2 and the second clamp 3, disconnect the power head 12 from the air-pressure drill rod 41, and lift out the down-the-hole hammer 42 and the air-pressure drill rod 41 in sequence.

[0067] S8. Backfilling with slag: Use the bucket of an excavator to backfill rock powder and slag into the steel casing 43. No stones should be mixed in the backfilled slag, and the particle size of the backfilled rock powder and slag should be less than 10mm.

[0068] S9. Pulling out the steel casing 43: Use a crawler crane to lift the vibratory pile-pulling clamp 7, making the arc-shaped suction cup 711 fit against the outer wall of the steel casing 43. Power on the electromagnetic suction device 71 to generate magnetic force and tighten it. Observe the reading on the reading device 74 and calculate the suction force based on the reading on the reading device 74. After confirming that the suction force is greater than the estimated pile-pulling resistance, start the vibratory hammer 72. While using the vibratory hammer 72 to drive the steel casing 43 to vibrate, use the crane to slowly lift the steel casing 43 until the steel casing 43 is pulled out. The vibration makes the backfill material inside the steel casing 43 compact, which can prevent the hole wall from collapsing.

[0069] Part Two: Construction of Large-Diameter Pipe Piles

[0070] S10, Pipe Pile 53 Measurement and Positioning: After leveling the site, RTK is used to measure the plane coordinates of the pile position and the elevation of the pile top.

[0071] S11. Leveling the pile controller 85: Move the casing drilling rig 1 to the pile position, use the crawler crane to lift the second clamp 3 and the pile controller 85 to the pile position, adjust the four vertical jacks 86, observe the corresponding four second levels 87, until all the leveling bubbles are centered, at this time the pile controller 85 is leveled, and the four vertical jacks 86 are locked.

[0072] S12. Install the reaming and pile driving drill bit 5: Connect the spiral drill rod 51 to the power head 12, connect the reaming cutting tooth drill bit 52 to the spiral drill rod 51, and insert it into the inner cavity of the pipe pile 53 after connection.

[0073] S13. Simultaneously lift the pipe pile 53 and the spiral drill rod 51: Using one end of the reaming cutter bit 52 as a fulcrum, thread a wire rope onto the other end of the pipe pile 53, and use a crawler crane to lift the pipe pile 53 and the spiral drill rod 51 to an upright position.

[0074] S14. Pipe pile 53 hoisting and positioning: Use a crawler crane to move the pipe pile 53 and the auger drill rod 51 to the pile position, open the second clamp 3, move the pipe pile 53 into the second clamp 3, and use the second clamp 3 to clamp the pipe pile 53.

[0075] S15. Verticality correction of pipe pile 53: Adjust the crane wire rope so that all the bubbles of the first level 81 are in the center. At this time, the pipe pile 53 is in a vertical state.

[0076] S16. Drilling and synchronous pile driving: Connect the top of the auger drill rod 51 to the power head 12. Clamp the top of the pipe pile 53 with the first clamp 2. Start the power head 12 to drive the reaming cutting bit 52 to drill, and at the same time drive the pipe pile 53 to sink synchronously through the first clamp 2.

[0077] S17. Piling: When the top surface of pipe pile 53 is close to the ground, a pile driver is used to connect the pile and continue drilling to the designed pile bottom elevation.

[0078] S18. Vibration compaction of pile bottom: After reaching the elevation, reverse the power head 12 to lift the auger drill rod 51 and the reaming cutter bit 52. Start the vibrator 13 to vibrate and compact the bottom of the pipe pile 53 to remove sediment.

[0079] With this, the construction of large-diameter pipe piles has been completed.

[0080] 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 large-diameter pipe pile driving device for riprap backfill layers, comprising a casing drilling rig (1), characterized in that, The casing drilling rig (1) is equipped with a power head (12), the power head (12) is equipped with a first clamp (2), the bottom end of the casing drilling rig (1) is equipped with a second clamp (3), and the power head (12) is selectively connected to a down-the-hole hammer drill (4) or a hole-reaming and pile-driving drill (5). The down-the-hole hammer drill bit (4) includes a compressed air drill rod (41) mounted on the power head (12), a down-the-hole hammer (42) mounted on the lower end of the compressed air drill rod (41), and a steel casing (43) sleeved on the outside of the compressed air drill rod (41). The borehole enlargement and pile driving drill (5) includes a spiral drill rod (51) mounted on the power head (12), a borehole enlargement cutting tooth drill bit (52) mounted on the lower end of the spiral drill rod (51), and a pipe pile (53) sleeved on the outside of the spiral drill rod (51). The first clamp (2) is used to selectively clamp the top end of the steel casing (43) or the pipe pile (53), and the second clamp (3) is used to correspondingly clamp the bottom end of the steel casing (43) or the pipe pile (53).

2. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 1, characterized in that, There is an annular gap between the steel casing (43) and the air-pressurized drill rod (41), and it also includes a dust-collecting slag cover (61) installed on the top of the steel casing (43) and covering the annular gap, and a slag discharge mechanism connected to the dust-collecting slag cover (61).

3. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 2, characterized in that, The dust collection hood (61) is a double-cylindrical structure with an open bottom and sealed top and sides. A water pipe assembly (62) is installed inside the dust collection hood (61), and a spray head (63) is installed on the water pipe assembly (62).

4. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 2, characterized in that, The slag discharge mechanism includes a slag inlet hose (64) connected to the dust suction slag cover (61), a slag pump (65) installed at the end of the slag inlet hose (64) away from the dust suction slag cover (61), and a second motor (66) installed at the output end of the slag pump (65). The slag pump (65) is provided with a slag discharge port (651).

5. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 1, characterized in that, It also includes a vibratory pile-pulling clamp (7), which includes an electromagnetic suction device (71) that is attached to the side of the steel casing (43) by an arc suction cup (711) and a vibratory hammer (72) that is slidably connected to the electromagnetic suction device (71).

6. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 5, characterized in that, A pressure sensor (73) is installed on the side of the arc suction cup (711) that is attracted to the steel casing (43).

7. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 1, characterized in that, The outer periphery of the steel casing (43) and / or the pipe pile (53) is equipped with a plurality of first level instruments (81) arranged in a ring array by elastic bands (83), which are connected by buttons (84).

8. The large-diameter pipe pile driving equipment for riprap backfill layers according to claim 1, characterized in that, It also includes a pile control device (85) installed on the casing drilling rig (1), the second clamp (3) is installed on the pile control device (85), and the pile control device (85) is provided with four vertical jacks (86) and four second levels (87) around its perimeter.

9. A method for driving large-diameter pipe piles in riprap backfill layers, characterized in that, The steps of using the large-diameter pipe pile driving equipment for riprap fill layers as described in any one of claims 1-8 include: The air-pressure drill rod (41) is installed on the power head (12), and the steel casing (43) is sleeved on the outer periphery of the air-pressure drill rod (41). At the same time, the top and bottom of the steel casing (43) are clamped by the first clamp (2) and the second clamp (3) respectively. The air compressor drives the air-pressure drill rod (41) to perform pilot rock-breaking drilling. At the same time, the first clamp (2) drives the steel casing (43) to sink synchronously to the design depth. Then the steel casing (43) is pulled out. Remove the compressed air drill rod (41) from the power head (12), install the spiral drill rod (51) on the power head (12), attach the pipe pile (53) to the outer periphery of the spiral drill rod (51), and use the first clamp (2) and the second clamp (3) to clamp the top and bottom ends of the pipe pile (53) respectively. The power head (12) on the casing drilling rig (1) drives the spiral drill rod (51) to drive the hole-expanding cutting tooth drill bit (52) to drill, and at the same time, the pipe pile (53) is driven to sink to the design elevation through the first clamp (2).

10. The method for driving large-diameter pipe piles in riprap backfill layers according to claim 9, characterized in that, It also includes the following steps: Before removing the steel casing (43), backfill the steel casing (43) with rock powder and stone chips.

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