Precast pile end carrier ramming and expanding device and method

Abstract

The invention discloses a precast pile end carrier ramming and expanding device and method. The precast pile end carrier ramming and expanding device comprises a precast pile, a feeding guide device used for feeding a mixture into the precast pile, a bottom guide protection pile tip fixed to the bottom of the precast pile and a ramming and expanding rod used for extruding the mixture. The bottom of the ramming and expanding rod is conical; guide pipes extending into the precast pile are formed on the feeding guide device and the bottom guide protection pile tip, and a plurality of extrusion holes are further formed in the side wall of the bottom guide protection pile tip. The operation of driving the precast pile into the soil body and ramming and expanding the bearing layer at the pile end to form the carrier can be realized by adopting one set of equipment, so that the equipment is simplified, materials are saved, the construction period is shortened, the damage to the pile body in the ramming and expanding process can be avoided, the pile body is re-driven after the carrier construction is finished, the hammer recovery standard is reached, and the construction efficiency is improved. And the pile forming quality of the pile is greatly improved, the risk of pile end settlement is further reduced, and the good anti-pulling performance is achieved.

Description

Technical field:

[0001] The invention belongs to the field of foundation, and in particular relates to a device and method for tamping and expanding a carrier at a prefabricated pile end. Background technology:

[0002] The tamping and expansion method of the precast pile end carrier refers to a method in which the hollow wall of the precast pile is used as a casing, the hollow part of the precast pile is used as a construction channel for the tamping and expansion rod and the mixed material, and the hammering force of a hydraulic hammer or a diesel hammer is used to tamp the tamping and expansion rod, and then the mixed material is added in sections to form a pile end carrier at the end of the precast pile.

[0003] During the construction process of the precast pile tamping and expansion carrier, a certain amount of mixed material will be filled into the hollow pile hole of the precast pile in batches. After each filling, it will be compacted by hammering. After repeating this step many times, the soil within a certain range below the pile end will be reinforced, forming a filling carrier composed of three parts: filling body, compacted soil body, and affected soil body. The filling carrier forms an expansion foundation, realizes the diffusion of force, and can give full play to the performance of the precast pile. Under certain geological conditions, this process can greatly reduce the length of the precast pile, and has considerable economic advantages compared to ordinary hammer precast piles. Specifically, CN 112144522A discloses a construction method for a prestressed pipe body and its special prestressed pipe body. However, it has the following problems:

[0004] 1. Two sets of equipment are needed. First, the prestressed pipe body needs to be driven into the soil, and then a rammer is needed to tamp the material with a column hammer. The two sets of equipment are divided into two processes, which are respectively handled by different personnel or companies. As a result, it is easy for the prestressed pipe body to be driven into the soil before the personnel responsible for the next process use the rammer to perform the tamping process. There will be a time gap in the process. During this period, if there is a gap in the bottom sealing plate, groundwater may leak into the prestressed pipe body. Due to the incompressibility of water, it will not be possible to tamp the prestressed pipe pile end carrier later.

[0005] 2. The sealing plate at the bottom of the prestressed pipe body is initially welded or bolted to the pipe pile. As mentioned above, when the prestressed pipe body is pressed to the preset depth, it is necessary to use a column hammer to destroy the sealing plate, and then pull the column hammer out. Then, after adding the mixed material into the prestressed pipe body, it is tamped with a column hammer. This is repeated to form an expanded pile end composite carrier. In this process, when the sealing plate is destroyed by tamping with a column hammer, since the sealing plate is fixedly connected to the prestressed pipe body, the destruction process may easily cause deformation or damage to the bottom of the prestressed pipe body. Moreover, during the tamping process after adding the mixed material, the mixed material simultaneously impacts the bottom of the prestressed pipe body, which may also easily cause deformation or damage to the bottom of the prestressed pipe body.

[0006] 3. When the material is rammed out of the prestressed pipe body, the mixed material mainly diffuses downward, and the concrete in the soil on both sides of the bottom of the prestressed pipe body is insufficiently diffused, which makes settlement easy to occur.

[0007] 4. When the existing structure adopts the tamping method, the column hammer needs to be in close contact with the prestressed pipe body and tamp the mixture by free fall. However, when the column hammer falls freely, friction will be generated with the prestressed pipe body, which causes the actual tamping force to be smaller than the preset tamping force. Due to the uncertainty of friction, the tamping force is also difficult to control accurately.

[0008] 5. The existing structural column hammer easily touches the inner wall of the prestressed pipe body when falling, causing the prestressed pipe body to deform or break. Summary of the invention:

[0009] The object of the present invention is to provide a device and method for tamping and expanding a prefabricated pile end carrier.

[0010] To solve the above problems, the technical solution of the present invention is:

[0011] A tamping and expanding device for a carrier at the end of a precast pile comprises a precast pile, a feeding guide device for feeding a mixed material into the precast pile, a bottom guide protection pile tip fixed to the bottom of the precast pile, and a tamping and expanding rod for extruding the mixed material; the bottom of the tamping and expanding rod is conical; the feeding guide device and the bottom guide protection pile tip are both formed with a guide tube extending into the interior of the precast pile, a plurality of extrusion holes are formed on the side wall of the bottom guide protection pile tip, and a sealing plate is detachably connected to the bottom of the bottom guide protection pile tip.

[0012] As a further improvement, the top surface of the sealing plate is formed with a plurality of pin blocks along the circumferential direction, which are inserted into the bottom of the precast pile and have an interference fit with the bottom guide protection pile tip. A guide block is also fixed to the top surface of the sealing plate, and a guide slope is formed at the inner end of the guide block, and the guide slope is located in the middle position of the sealing plate.

[0013] As a further improvement, flanges are fixed on the feeding guide device and the bottom guide protection pile tip; the flange of the feeding guide device is fixedly connected to the end face of the top of the precast pile by bolts; the flange of the bottom guide protection pile tip is fixedly connected to the end face of the bottom end of the precast pile; a hydraulic rod puller for pulling up the tamping and expansion rod is fixed above the feeding guide device; the tamping and expansion rod is marked with scales.

[0014] A further improvement is that the hydraulic rod puller includes a sleeve body, a cava with a thickness gradually increasing from bottom to top is installed circumferentially on the top of the sleeve body, a ring is provided on the outer periphery of the upper part of the sleeve body, a telescopic rod is fixedly connected to the bottom of the sleeve body, and the top of the telescopic rod is connected to the ring; the inner surface of the ring is fitted with the outer surface of the cava.

[0015] As a further improvement, the telescopic rod is an oil cylinder, a gas cylinder or an electric cylinder.

[0016] As a further improvement, a plurality of vertically arranged inverted tooth racks are fixed along the circumferential direction on the outer side wall of the bottom guide protection pile tip.

[0017] As a further improvement, a U-shaped material guide trough is fixed on one side of the top of the feeding guide device, and a plurality of stiffening plates are fixed on the side wall of the feeding guide device along the circumferential direction.

[0018] A method for tamping and expanding a carrier at the end of a prefabricated pile, using the above-mentioned tamping and expanding device for the carrier at the end of a prefabricated pile, comprises the following steps:

[0019] Step 1: Weld and fix the bottom guide protection pile tip to the bottom of the prefabricated pile, install a sealing plate at the bottom of the bottom guide protection pile tip, and then use a striking body to drive the prefabricated pile into the ground to a preset depth; the striking body includes a hydraulic hammer and a diesel hammer;

[0020] Step 2: fix the feeding guide device to the top of the precast pile, insert the tamping and expansion rod into the pile cap of the striking body, so that the tamping and expansion rod extends into the precast pile and strikes downward, squeezes the sealing plate out of the bottom guide to protect the pile tip, and then continues to press to form a pit body, the distance from the bottom of the pit body to the bottom of the precast pile is h, and h is greater than the diameter of the precast pile;

[0021] Step 3: The winch lifting system on the striking body pulls the tamping rod out of the precast pile, and then adds the mixed material to the pit body through the feeding guide device until the mixed material reaches the position between the top and bottom of the guide tube where the bottom guide protection pile tip extends into the interior of the precast pile. The striking body strikes the striking surface of the top of the tamping rod that has been inserted into the pile cap of the striking body through its own striking hammer, so that the tamping rod strikes the mixed material according to the preset striking force, wherein the tamping rod does not extend downward beyond the bottom of the pit body when striking the mixed material, and is not higher than the bottom guide protection pile tip extending into the interior of the precast pile. the top of the guide tube; step 4, repeating step 3 until the mixed material is struck to reach the preset penetration standard requirement and reaches the bottom of the pile body, thereby forming a precast pile end carrier; wherein, after each injection of the mixed material, the tamping and expansion rod strikes the mixed material until it reaches the preset penetration standard requirement or the position reached by the tamping and expansion rod last time, thereby tamping the mixed material in sections and batches, and gradually forming a precast pile end carrier; step 5, completely taking out the tamping and expansion rod and removing the feeding guide device, and striking the precast pile with the striking body until the hammering standard of the precast pile is reached.

[0022] As a further improvement, the hydraulic rod puller as claimed in the claim is fixed on the top of the feeding guide device.

[0023] Before pulling the tamping and expanding rod out of the precast pile in step three and step five, the tamping and expanding rod is first pulled upward by a preset distance by a hydraulic rod puller, and then the winch lifting system on the striking body pulls the tamping and expanding rod out of the precast pile.

[0024] As a further improvement, a plurality of inverted tooth racks are fixed circumferentially on the outer side wall of the bottom guide protection pile tip; the inverted tooth racks are used to improve the pull-out bearing capacity of the precast piles, the tamping and expansion rods are marked with scale lines, and the penetration degree is controlled and read by the scale lines on the tamping and expansion rods.

[0025] Advantages of the present invention:

[0026] 1. The present invention can realize the operation of manufacturing the prefabricated pile end carrier by using a set of striking bodies, thus simplifying the equipment, saving materials, shortening the construction period, and because the tamping rod is in direct contact with the mixed material, the loss of the tamping energy of the tamping rod due to groundwater is avoided, and the filling material is tamped layer by layer from the bottom to the top of the pit, thereby improving the quality of the prefabricated pile end carrier.

[0027] 2. The special structure of the sealing plate makes it extremely easy to detach from the precast pile, and can effectively prevent the soil from entering the precast pile and obstructing the downward movement of the tamping and expansion rod, thereby preventing it from detaching and causing damage to the precast pile. When detaching, it moves sideways, thereby not obstructing the tamping and expansion rod, allowing the tamping and expansion rod to reach the preset depth directly.

[0028] 3. Since the tamping rod is inserted into the mixed material for tamping and expansion and the bottom of the tamping rod is conical, the mixed material is dispersed and expanded laterally, which can significantly increase the influence on the soil at the pile end.

[0029] 4. After the carrier construction is completed, the precast pile body is re-driven to reach the hammer end standard, which can further reduce the risk of pile end settlement.

[0030] 5. Since the side wall of the bottom guide protection pile tip is provided with a number of extrusion holes and inverted tooth racks, the mixed material can pass through the extrusion holes into the surrounding soil and form a whole with the pile end carrier, so that the inverted tooth rack extends into the shape of the pile end carrier to achieve anti-pullout connection, which has excellent anti-pullout performance.

[0031] 6. The use of a striking body and a tamping and expanding rod in direct contact with the mixed material makes the pressure control more precise. A scale is set on the tamping and expanding rod to facilitate accurate determination of the position reached by the tamping and expanding rod and control of precise feeding.

[0032] 7. The setting of the guide tube avoids direct contact between the tamping and expanding rod and the inner wall of the precast pile, thus overcoming the problem that the existing tamping and expanding rod easily touches the inner wall of the precast pile and causes damage to the precast pile. Description of the drawings:

[0033] Figure 1 It is a schematic diagram of the overall structure of Example 1;

[0034] Figure 2 Schematic diagram of the three-dimensional structure of the sealing plate;

[0035] Figure 3 A schematic diagram of the three-dimensional structure of the bottom guide protection pile tip;

[0036] Figure 4 A diagram of the tamping and expanding device for the end carrier of a precast pile with a hydraulic rod puller;

[0037] Figure 5This is a schematic diagram of the structure of the hydraulic rod puller of Example 2. Specific implementation method:

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0039] Example 1

[0040] like Figure 1-Figure 3 The present invention shows a prefabricated pile end carrier tamping and expanding device, comprising a prefabricated pile 1, a feeding guide device 2, a bottom guide protection pile tip 3, a guide tube 4, a tamping and expanding rod 5, a sealing plate 6, a latch block 8, a guide block 9, a guide slope 10, a flange 11, a reverse tooth rack 12, a material extrusion hole 13, a U-shaped material guide trough 14 and a stiffening plate 15.

[0041] Among them, the precast piles in the present invention include but are not limited to precast concrete square piles, precast concrete pipe piles, prestressed concrete square piles, prestressed concrete pipe piles, prestressed (super) high-strength concrete square piles, prestressed (super) high-strength concrete pipe piles, steel pipe piles, etc.

[0042] A feeding guide device 2 is fixed on the top of the precast pile 1, and a bottom guide protection pile tip 3 is fixed on the bottom. The top guide sleeve 2 and the bottom guide protection pile tip 3 are both formed with a guide tube 4 extending into the interior of the precast pile 1, and the guide tube 4 is slidably connected to the tamping expansion rod 5. A flange 11 is fixed on the feeding guide device 2 and the bottom guide protection pile tip 3. The flange 11 of the feeding guide device 2 is fixedly connected to the end face of the top of the precast pile 1 by bolts, and the flange 11 of the bottom guide protection pile tip 3 is welded to the end face of the bottom end of the precast pile 1. A plurality of inverted tooth racks 12 are fixed along the circumferential direction on the outer side wall of the bottom guide protection pile tip 3, and a plurality of extrusion holes 13 are opened along the circumferential direction on the side wall of the bottom guide protection pile tip 3. A U-shaped material guide trough 14 is fixed on one side of the top of the feeding guide device 2, and a plurality of stiffening plates 15 are fixed along the circumferential direction on the side wall of the feeding guide device 2. A sealing plate 6 is installed at the bottom of the bottom guide protection pile tip 3, and a plurality of latch blocks 8 are formed on the top surface of the sealing plate 6 along the circumferential direction, which are inserted into the bottom of the prefabricated pile 1 and have an interference fit with the bottom guide protection pile tip 3. A guide block 9 is also fixed on the top surface of the sealing plate 6, and a guide slope 10 is formed at the inner end of the guide block 9, and the guide slope 10 is located in the middle position of the sealing plate 6.

[0043] The method for using the prefabricated pile end carrier tamping and expansion device comprises the following steps:

[0044] The bottom guide protection pile tip 3 is welded and fixed to the bottom of the prefabricated pile 1, and the sealing plate 6 is installed at the bottom of the bottom guide protection pile tip 3, and then the prefabricated pile 1 is driven into the preset depth underground by a striking body; the striking body includes a hydraulic hammer and a diesel hammer.

[0045] Step 2, fix the feeding guide device 2 on the top of the precast pile 1, insert the tamping and expanding rod 5 into the pile cap of the striking body, and then extend the tamping and expanding rod 5 into the precast pile 1 to strike downward. When the hydraulic hammer drives the tamping and expanding rod 5 to press, it hits the sealing plate 6. Under the guidance of the guiding inclined surface 10, the sealing plate 6 will move downward and to one side, thereby separating from the precast pile 1, and no longer hindering the downward movement of the tamping and expanding rod 5, so that there is no need to break the sealing plate 6 before hammering the soil, and it can also prevent the bottom of the precast pile 1 from being deformed or damaged when the sealing plate separates from the precast pile 1.

[0046] The tamping rod 5 is continuously driven downward to form a pit body, and the distance from the bottom to the bottom of the precast pile 1 is h, and h is greater than the diameter of the precast pile 1, so as to form a precast pile end carrier with sufficient supporting force.

[0047] Step 3: The winch lifting system on the striking body pulls the tamping and expanding rod 5 out of the precast pile 1, and then adds the mixed material into the pit body through the feeding guide device 2, until the mixed material reaches the position between the top and bottom of the guide tube 4 where the bottom guide protection pile tip 3 extends into the interior of the precast pile 1, and the striking body strikes the striking surface of the top of the tamping and expanding rod 5 that has been inserted into the pile cap of the striking body through its own striking hammer, so that the tamping and expanding rod 5 strikes the mixed material according to the preset striking force, wherein the tamping and expanding rod 5 does not extend downward beyond the bottom of the pit body when striking the mixed material, and is not higher than the top of the guide tube 4 where the bottom guide protection pile tip 3 extends into the interior of the precast pile 1;

[0048] Step 4, repeating step 3 until the mixed material reaches the bottom of the pile body after being hit to reach the preset penetration standard requirement, thereby forming a prefabricated pile end carrier; wherein, after each time the mixed material is added, the tamping rod 5 hits the mixed material until it reaches the preset penetration standard requirement or the position reached by the tamping rod 5 last time, thereby tamping the mixed material in sections and batches, and gradually forming a prefabricated pile end carrier; the penetration degree is controlled and read by the scale line on the tamping rod;

[0049] Step 5: completely take out the tamping rod 5 and dismantle the feeding guide device 2, and use the striking body to strike the precast pile 1 until the hammering standard of the precast pile is reached (such as 2 cm / 10 strikes, etc.).

[0050] Example 2

[0051] like Figure 4 and Figure 5As shown, in Example 2, based on Example 1, the hydraulic rod puller 7 has the following structure: it includes a sleeve 71, a cava 74 with a thickness gradually increasing from bottom to top is installed circumferentially on the top of the sleeve 71, a ring 73 is sleeved on the upper outer periphery of the sleeve 71, a telescopic rod 72 is fixedly connected to the bottom of the sleeve 71, and the top of the telescopic rod 72 is connected to the ring 73; the inner surface of the ring 73 is fitted with the outer surface of the cava 74.

[0052] In this way, the slip 74 can be tightened by pushing the ring 73, thereby holding the tamping and expanding rod 5 tightly, and then continuing to move upward to pull the tamping and expanding rod 5 up a certain distance, thereby achieving the action of first pulling the tamping and expanding rod 5 upward by a preset distance through the hydraulic rod puller 7, and then the winch lifting system on the striking body pulls the tamping and expanding rod 5 out of the precast pile 1.

[0053] The above embodiment is only a specific implementation of the present invention and is not intended to be a limitation of the present invention. Any simple improvements and replacements made thereto are within the protection scope of the present invention.

Claims

1. A prefabricated pile end carrier tamping and expansion device, characterized in that: The invention comprises a precast pile (1), a feeding guide device (2) for feeding mixed materials into the precast pile, a bottom guide protection pile tip (3) fixed to the bottom of the precast pile, and a tamping and expanding rod (5) for extruding the mixed materials; the bottom of the tamping and expanding rod (5) is conical; the feeding guide device (2) and the bottom guide protection pile tip (3) are both formed with a guide tube (4) extending into the interior of the precast pile (1); a plurality of extrusion holes (13) are formed on the side wall of the bottom guide protection pile tip (3); and a sealing plate (6) is detachably connected to the bottom of the bottom guide protection pile tip.

2. The prefabricated pile end carrier tamping and expanding device according to claim 1, characterized in that: The top surface of the sealing plate (6) is formed with a plurality of latch blocks (8) along the circumferential direction, which are inserted into the bottom of the prefabricated pile (1) and are interference-fitted with the bottom guide protection pile tip (3). A guide block (9) is also fixed to the top surface of the sealing plate (6). A guide slope (10) is formed at the inner end of the guide block (9). The guide slope (10) is located in the middle of the sealing plate (6).

3. The precast pile end carrier tamping and expanding device according to claim 1, characterized in that: Flanges (11) are fixed on the feeding guide device (2) and the bottom guide protection pile tip (3); the flange (11) of the feeding guide device (2) is fixedly connected to the end surface of the top of the precast pile (1) by bolts; the flange (11) of the bottom guide protection pile tip (3) is fixedly connected to the end surface of the bottom of the precast pile (1); a hydraulic rod puller (7) for pulling up the tamping and expansion rod (5) is fixed above the feeding guide device (2); and the tamping and expansion rod (5) is marked with scales.

4. The prefabricated pile end carrier tamping and expanding device according to claim 3, characterized in that: The hydraulic rod puller (7) comprises a sleeve (71), a slip (74) with a thickness gradually increasing from bottom to top is installed on the top of the sleeve (71) along the circumferential direction, a collar (73) is sleeved on the outer circumference of the upper part of the sleeve (71), a telescopic rod (72) is fixedly connected to the bottom of the sleeve (71), and the top of the telescopic rod (72) is connected to the collar (73); the inner surface of the collar (73) is arranged to fit the outer surface of the slip (74).

5. The prefabricated pile end carrier tamping and expanding device according to claim 4, characterized in that: The telescopic rod (72) is an oil cylinder, a gas cylinder or an electric cylinder.

6. The precast pile end carrier tamping and expanding device according to claim 1, characterized in that: A plurality of vertically arranged inverted tooth racks (12) are fixed on the outer side wall of the bottom guide protection pile tip (3) along the circumferential direction.

7. The precast pile end carrier tamping and expanding device according to claim 1, characterized in that: A U-shaped material guide trough (14) is fixed on one side of the top of the material feeding guide device (2), and a plurality of stiffening plates (15) are fixed along the circumferential direction on the side wall of the material feeding guide device (2).

8. A method for tamping and expanding a prefabricated pile end carrier, characterized in that: The precast pile end carrier tamping and expanding device according to claim 1 comprises the following steps: Step 1: Weld and fix the bottom guide protection pile tip (3) to the bottom of the prefabricated pile (1), install the sealing plate (6) at the bottom of the bottom guide protection pile tip (3), and then use a striking body to drive the prefabricated pile (1) into the ground to a preset depth; the striking body includes a hydraulic hammer and a diesel hammer; Step 2: fix the feeding guide device (2) to the top of the precast pile (1), insert the tamping and expanding rod (5) into the pile cap of the striking body, so that the tamping and expanding rod (5) extends into the precast pile (1) and strikes downward, squeezes the sealing plate (6) away from the bottom guide protection pile tip (3), and then continues to press to form a pit body, the distance from the bottom of the pit body to the bottom of the precast pile (1) is h, and h is greater than one times the diameter of the precast pile (1); Step 3: The winch lifting system on the striking body pulls the tamping and expanding rod (5) out of the precast pile (1), and then the mixed material is added to the pit body through the feeding guide device (2) until the mixed material reaches the position between the top and the bottom of the guide tube (4) where the bottom guide protection pile tip (3) extends into the interior of the precast pile (1), and the striking body strikes the striking surface of the top of the tamping and expanding rod (5) that has been inserted into the pile cap of the striking body through its own striking hammer, so that the tamping and expanding rod (5) strikes the mixed material according to the preset striking force, wherein the tamping and expanding rod (5) does not extend below the bottom of the pit body when striking the mixed material, and is not higher than the top of the guide tube (4) where the bottom guide protection pile tip (3) extends into the interior of the precast pile (1); Step 4, repeating step 3 until the mixed material reaches the bottom of the pile body after being hit to reach the preset penetration standard requirement, thereby forming a prefabricated pile end carrier; wherein, after each time the mixed material is added, the tamping rod (5) hits the mixed material until it reaches the preset penetration standard requirement or the position reached by the tamping rod (5) last time, thereby tamping the mixed material in sections and batches, and gradually forming a prefabricated pile end carrier; Step 5: completely take out the tamping rod (5) and dismantle the feeding guide device (2), and then use the striking body to strike the precast pile (1) until the hammering standard of the precast pile is reached.

9. The method for tamping and expanding the precast pile end carrier according to claim 8, characterized in that: The hydraulic rod puller (7) described in claim 3 is fixed on the top of the feeding guide device (2). Before pulling the tamping and expanding rod (5) out of the precast pile (1) in steps three and five, the tamping and expanding rod (5) is first pulled upward by a preset distance by the hydraulic rod puller (7), and then the winch lifting system on the striking body pulls the tamping and expanding rod (5) out of the precast pile (1).

10. The method for tamping and expanding the precast pile end carrier according to claim 8, characterized in that: A plurality of inverted tooth racks (12) are fixed along the circumferential direction on the outer side wall of the bottom guide protection pile tip (3); the inverted tooth racks (12) are used to improve the pull-out bearing capacity of the prefabricated pile; the tamping and expansion rod (5) is marked with scale lines, and the penetration degree is controlled and read through the scale lines on the tamping and expansion rod (5).

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