A method for preventing floating of anti-buoyancy pile shoes and reinforcing cages

Abstract

This invention discloses an anti-buoyancy pile shoe and a method for preventing the rebar cage from floating, belonging to the field of underground pile foundation engineering. The anti-buoyancy pile shoe includes a pile shoe body, an anchor bolt telescopic mechanism, and a triggering mechanism. The pile shoe body includes a cylinder, a bottom sealing plate, and a top sealing plate. The triggering mechanism includes a vertical sleeve and a trigger rod, which can move up and down within the vertical sleeve. An end plate is provided at the bottom, and a chuck is provided at the top. The anchor bolt telescopic mechanism includes a positioning cylinder, an anchor bolt, a spring, and a steel strand. The positioning cylinder is connected to the cylinder body, and the anchor bolt is located inside the positioning cylinder, with one end facing the outside of the cylinder body and the other end equipped with a spring. One end of the steel strand is wound around a turntable, and the other end is fixedly connected to the anchor bolt. Rotating the turntable allows the anchor bolt to retract into the positioning cylinder and the spring to store energy. When the trigger rod moves downward, the chuck can be fixed to the turntable. When the trigger rod moves upward, causing the chuck to separate from the turntable, the spring can push the anchor bolt out and insert it into the soil on the side of the pile hole, effectively preventing the pile foundation from floating.

Description

Technical Field

[0001] This invention relates to an anti-buoyancy pile shoe and a method for preventing the rebar cage from floating, belonging to the field of underground pile foundation engineering. Background Technology

[0002] Cast-in-place piles are widely used in building construction, hydraulic engineering, and bridge projects due to their unique advantages such as strong adaptability, high bearing capacity, moderate cost, stable quality in the later stages, low construction noise, and minimal interference with adjacent structures. The problem of reinforcement cage floating is one of the most common and challenging issues encountered by construction companies. During concrete pouring, concrete is poured from bottom to top. When the pouring speed is too fast, the upward force of the concrete on the reinforcement cage, as well as the force exerted on the reinforcement cage when lifting the tremie pipe due to excessive burial depth, can easily cause the reinforcement cage to float. This reduces the effective length of the pile and significantly compromises the quality of the project. Therefore, solving the problem of reinforcement cage floating during cast-in-place pile construction is crucial for ensuring the quality of the pile foundation. Summary of the Invention

[0003] To address the problem of steel cage floating in existing cast-in-place piles, this invention provides an anti-floating pile shoe and a method for preventing steel cage floating, which can effectively solve the problem of steel cage floating.

[0004] To solve the above technical problems, the present invention includes the following technical solutions:

[0005] An anti-buoyancy pile shoe includes a pile shoe body, an anchor bolt telescopic mechanism, and a triggering mechanism;

[0006] The pile shoe body includes a cylinder, a bottom sealing plate and a top sealing plate. The cylinder is provided with several side through holes, and the bottom sealing plate is provided with a bottom through hole at the center.

[0007] The triggering mechanism includes a vertical sleeve and a trigger rod. The bottom of the vertical sleeve is fixed to the bottom sealing plate, and the center hole of the vertical sleeve is connected to the bottom through hole. The trigger rod is set inside the vertical sleeve and can move up and down along the vertical sleeve. Both ends of the trigger rod extend out of the vertical sleeve. An end plate is set at the bottom and a chuck is set at the top. A turntable is fitted on the vertical sleeve and can rotate around the vertical sleeve.

[0008] The anchor bolt telescopic mechanism includes a positioning cylinder, an anchor bolt, a spring, and a steel strand; one end of the positioning cylinder is fixed to the cylinder body, and the central hole of the positioning cylinder is connected to the side through hole; the anchor bolt is set inside the positioning cylinder, with one end of the anchor bolt facing the outside of the cylinder body and the other end equipped with a spring; one end of the steel strand is wound on the turntable, and the other end is fixedly connected to the end of the anchor bolt.

[0009] Rotating the turntable allows the anchor rod to retract into the positioning cylinder and the spring to store energy. The trigger rod moves downward along the vertical sleeve, which allows the chuck to be fixed with the vertical sleeve and the turntable, restricting the rotation of the turntable. When the end plate is subjected to an upward force, it can cause the trigger rod to move upward along the vertical sleeve. After the turntable separates from the chuck, it resumes rotation. Under the push of the spring, one end of the anchor rod can be ejected from the side through hole.

[0010] Furthermore, the chuck is provided with a first positioning block and a second positioning block, the top of the vertical sleeve is provided with a first positioning groove that matches the first positioning block, and the top of the turntable is provided with a second positioning groove that matches the second positioning block.

[0011] When the first positioning block is in the first positioning groove, the second positioning block is in the second positioning groove, and the chuck is fixed to the vertical sleeve and the turntable.

[0012] Furthermore, the end of the positioning cylinder facing the turntable is inclined downwards, and the angle between the positioning cylinder and the horizontal plane is α, where 5°≤α≤30°.

[0013] Furthermore, the inner diameter of the positioning cylinder is D1, a sliding groove is provided inside the positioning cylinder, the diameter of the sliding groove is D2, the diameter of the anchor rod is D3, the end of the anchor rod connected to the steel strand is an enlarged end, and the diameter of the enlarged end of the anchor rod is D4, satisfying: D3<D1<D4<D2.

[0014] Accordingly, the present invention also provides a method for preventing the rebar cage from floating, which uses the aforementioned anti-floating pile shoe. The method for preventing the rebar cage from floating includes the following steps:

[0015] Step 1: With the chuck and turntable separated, rotate the turntable to wind the steel strand around it. The steel strand pulls the anchor rod back into the positioning cylinder and compresses the spring to store energy. Then, the chuck and turntable are locked together, and the turntable is restricted from rotating.

[0016] Step 2: Install the anti-buoyancy pile shoe at the bottom of the reinforcing cage. When the reinforcing cage is lowered to the bottom of the pile hole, the end plate is pushed by the jacking force, causing the trigger rod to move upward relative to the vertical sleeve, separating the chuck from the turntable. The spring pushes the anchor rod to be quickly ejected from the positioning cylinder and inserted into the soil on the side of the pile hole.

[0017] Compared with existing technologies, this invention, by adopting the above technical solutions, has the following advantages and positive effects: The anti-buoyancy pile shoe of this invention can retract the anchor rod into the positioning cylinder and store spring energy by rotating the disc. The chuck is fixed to the vertical sleeve and the disc by moving the trigger rod. When the anti-buoyancy pile shoe touches the bottom of the pile hole, the chuck separates from the vertical sleeve and the disc. Under the pushing action of the spring, the anchor rod is ejected from the positioning cylinder and inserted into the soil on the side of the pile hole, thereby effectively preventing the reinforcing cage from floating and improving the quality and safety of pile foundation construction. The device has a reasonable structural design and a reliable triggering mechanism, accurately sensing the pile shoe's bottoming state and releasing the anchor rod in a timely manner. The anchor rod extension mechanism uses a spring energy storage method, resulting in rapid response and good anchoring effect. The overall structure is compact, easy to install, and suitable for various pile foundation construction environments. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the anti-buoyancy pile shoe in one embodiment of the present invention;

[0019] Figure 2 for Figure 1 Sectional view along the middle AA;

[0020] Figure 3 This is a schematic diagram of the anchor bolt of the anti-buoyancy pile shoe extending in one embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the structure of the anti-buoyancy pile shoe body in one embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the triggering mechanism in one embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of an anchor bolt telescopic mechanism according to an embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram showing the inclined arrangement of the anchor bolt telescopic mechanism of the anti-buoyancy pile shoe in one embodiment of the present invention.

[0025] The numbers in the diagram are as follows:

[0026] 10-Pile shoe body; 11-Cylinder body; 111-Side through hole; 12-Bottom sealing plate; 121-Bottom through hole; 13-Top sealing plate;

[0027] 20-Anchor bolt telescopic mechanism; 21-Positioning cylinder; 22-Anchor bolt; 23-Spring; 24-Steel strand;

[0028] 30-Triggering mechanism; 31-Vertical sleeve; 311-First positioning groove; 32-Trigger rod; 33-End plate; 34-Chuck; 341-First positioning block; 342-Second positioning block; 35-Turntable; 351-Second positioning groove. Detailed Implementation

[0029] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a method for preventing the floating of anti-buoyancy pile shoes and reinforcing cages provided by the present invention. The advantages and features of the present invention will become clearer from the following description. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0030] Example 1

[0031] Combination Figures 1 to 3 As shown, the anti-buoyancy pile shoe provided in this embodiment includes a pile shoe body 10, an anchor bolt telescopic mechanism 20, and a triggering mechanism 30.

[0032] Combination Figures 1 to 4 As shown, the pile shoe body 10 includes a cylindrical body 11, a bottom sealing plate 12, and a top sealing plate 13. The cylindrical body 11 can be a cylindrical structure, the bottom sealing plate 12 can be a conical plate and welded to the bottom of the cylindrical body 11, and the top sealing plate 13 is detachably connected to the cylindrical body 11. The cylindrical body 11, the bottom sealing plate 12, and the top sealing plate 13 form a structure with an internal cavity. The cylindrical body 11 is provided with four side through holes 111, and the number of side through holes 111 can be set as needed. The bottom sealing plate 12 has a bottom through hole 121 at its center.

[0033] Combination Figures 1 to 5As shown, the triggering mechanism 30 includes a vertical sleeve 31 and a trigger rod 32. The bottom of the vertical sleeve 31 is welded and fixed to the bottom sealing plate 12, and the central hole of the vertical sleeve 31 is connected to the bottom through hole. The trigger rod 32 is located inside the vertical sleeve 31, and both ends of the trigger rod 32 extend out of the vertical sleeve 31. An end plate 33 is provided at the bottom of the trigger rod 32, and a chuck 34 is provided at the top of the trigger rod 32. When the anti-buoyancy pile shoe touches the bottom of the pile hole, the end plate 33 can increase the contact area, and the force on the end plate will push the trigger rod to move upward relative to the vertical sleeve 31. The chuck 34 has a disc-shaped structure, and a first positioning block 341 and a second positioning block 342 are provided on the chuck 34. Both the first positioning block and the second positioning block have a toothed structure, and the first positioning block is located near the center of the chuck. The top of the vertical sleeve 31 is provided with a first positioning groove 311 that matches the first positioning block 341. A turntable 35 is fitted on the vertical sleeve 31 and can rotate around the vertical sleeve 31. The top of the turntable 35 is provided with a second positioning groove 351 that matches the second positioning block 342. When the first positioning block is located in the first positioning groove, the chuck is fixedly connected to the vertical sleeve 31, and the chuck cannot rotate the rod, but can only move upward under the action of external force. At this time, the second positioning block is located in the second positioning groove, so that the turntable cannot rotate either. When the end plate is pushed upward by the force, the first positioning block and the second positioning block move out of the first positioning groove and the second positioning groove respectively, so that the turntable can resume free rotation. It should be noted that the second positioning block and the second positioning groove are to prevent the trigger rod from rotating. Other measures can also be taken to restrict the rotation of the trigger rod, such as setting the trigger rod to a rectangular cross section, a pentagonal cross section, or a hexagonal cross section, etc., and the inner cross section of the vertical sleeve can match the cross section of the tactile rod.

[0034] Combination Figures 1 to 6 As shown, the anti-buoyancy pile shoe includes four anchor bolt telescopic mechanisms 20. Each anchor bolt telescopic mechanism 20 includes a positioning cylinder 21, an anchor bolt 22, a spring 23, and a steel strand 24. One end of the positioning cylinder 21 is welded or threaded to the cylinder body 11, and the central hole of the positioning cylinder 21 communicates with the side through hole 111. The anchor bolt 22 is disposed inside the positioning cylinder, with one end being a pointed tip facing outward from the cylinder body 11, and the other end being provided with a spring 23, which can push the anchor bolt 22 to extend outward from inside the positioning cylinder. One end of the steel strand 24 is wound around the turntable 35, and the other end is fixedly connected to the end of the anchor bolt.

[0035] The working principle of the anti-buoyancy pile shoe is as follows: the chuck separates from the turntable, rotating the turntable causes the steel strand to wind around it, pulling the anchor rod back into the positioning cylinder and compressing the spring to store energy; then the chuck and turntable are locked together; the anti-buoyancy pile shoe is installed at the bottom of the reinforcing cage. When the reinforcing cage is lowered to the bottom of the pile hole, the end is subjected to a pushing force, causing the trigger rod to move upward relative to the vertical sleeve 31, separating the chuck from the turntable. The spring pushes the anchor rod to quickly shoot out from the positioning cylinder and insert it into the soil on the side of the pile hole, thus preventing the reinforcing cage from floating. Multiple anchor rod telescopic mechanisms are evenly distributed around the pile shoe body. When all anchor rods extend and insert into the soil of the pile hole at the same time, they can provide all-round anti-buoyancy capability, effectively preventing the pile from floating under the action of groundwater pressure.

[0036] In one specific embodiment, such as Figure 7 As shown, the positioning cylinder is tilted downwards at the end facing the turntable, with an angle α between the positioning cylinder and the horizontal plane, where 5° ≤ α ≤ 30°. This tilted design allows the anchor rod to tilt upwards and insert into the soil when extended, increasing pull-out resistance. For example, α is 15° or 20°. This angle ensures that the anchor rod is tilted into the soil without affecting its expansion and contraction due to an excessively large angle. The tilted design of the anchor rod increases pull-out resistance and improves its anti-buoyancy effect.

[0037] In one specific embodiment, the inner diameter of the positioning cylinder is D1, and a sliding groove with a diameter of D2 is provided inside the positioning cylinder. The diameter of the sliding groove is D3, and the end of the anchor rod connected to the steel strand is an enlarged end with a diameter of D4, satisfying the following condition: D3 < D1 < D4 < D2. This dimensional design ensures that the anchor rod can slide freely within the positioning cylinder, while the enlarged end can move within the sliding groove without completely detaching from the positioning cylinder, thus improving the stability and safety of the structure.

[0038] Example 2

[0039] This embodiment provides a method for preventing a reinforcing cage from floating, and the specific structure of the floating pile shoe is as described in Embodiment 1. The method for preventing a reinforcing cage from floating includes the following steps:

[0040] Step 1: With the chuck 34 and turntable 35 separated, rotate the turntable 35 to wind the steel strand 24 onto the turntable. The steel strand 24 pulls the anchor rod 22 back into the positioning cylinder 21 and compresses the spring 23 to store energy. Then, the chuck 34 and turntable 35 are locked together.

[0041] In this step, the turntable first needs to rotate to store energy in the spring. Then, the chuck is moved to restrict the rotation of the turntable, keeping the spring in a stored state. When the chuck has a first positioning block and a second positioning block, the top of the vertical sleeve has a first positioning groove that matches the first positioning block, and the top of the turntable has a second positioning groove that matches the second positioning block, the specific operation is as follows: First, ensure that the chuck is separated from the vertical sleeve 31 and the turntable. At this time, the first positioning block and the second positioning block on the chuck are not engaged with the first positioning groove on the top of the vertical sleeve and the second positioning groove on the top of the turntable, respectively. Then, the turntable is rotated manually or with the aid of tools, so that the steel strand gradually winds onto the turntable. As the turntable rotates, the steel strand pulls the anchor rod from outside the positioning cylinder back into the positioning cylinder, while compressing the spring connected to the anchor rod, keeping the spring in a compressed and stored state. When the anchor rod is fully retracted into the positioning cylinder and the spring is fully compressed, the trigger rod moves downward, causing the chuck to move down until the first and second positioning blocks on the chuck enter the first positioning groove of the vertical sleeve and the second positioning groove of the turntable, respectively. This achieves the locking and fixing of the chuck with the vertical sleeve and the turntable, preventing the turntable from rotating in the opposite direction to release the anchor rod.

[0042] Step 2: Install the anti-buoyancy pile shoe at the bottom of the reinforcing cage. When the reinforcing cage is lowered to the bottom of the pile hole, the end plate is pushed by the jacking force, causing the trigger rod to move upward relative to the vertical sleeve, separating the chuck from the turntable. The spring pushes the anchor rod to be quickly ejected from the positioning cylinder and inserted into the soil on the side of the pile hole.

[0043] In this step, after the reinforcing cage is placed in place, the turntable resumes rotation so that the spring can eject the anchor bolt. When the chuck is equipped with a first positioning block and a second positioning block, the top of the vertical sleeve has a first positioning groove matching the first positioning block, and the top of the turntable has a second positioning groove matching the second positioning block, the specific operation is as follows: First, install the anti-buoyancy pile shoe from step one at the bottom of the reinforcing cage, ensuring a secure installation. Then, lower the entire reinforcing cage with the anti-buoyancy pile shoe into the pre-drilled pile hole. When the reinforcing cage descends to the bottom of the pile hole, the end plate at the bottom of the trigger rod contacts the bottom of the pile hole and receives an upward pushing force. Under this pushing force, the trigger rod moves upward relative to the fixed vertical sleeve, causing the chuck to move upward. Once the chuck reaches a certain height, the first and second positioning blocks on the chuck disengage from the first positioning groove of the vertical sleeve and the second positioning groove of the turntable, respectively, completely separating the chuck from the vertical sleeve and the turntable. At this point, the turntable loses its fixation, and under the energy released by the compression spring, the anchor rod is rapidly ejected, shooting out through the side through-hole along the positioning cylinder and penetrating deep into the soil on the side of the pile hole. Because the end of the positioning cylinder facing the turntable is inclined downwards, forming an angle of 5° to 30° with the horizontal plane, the anchor rod inserts into the soil in an upward inclined direction when it is ejected, increasing the pull-out resistance. After multiple anchor rods are ejected simultaneously and inserted into the surrounding soil, they form an all-round anti-buoyancy fixing point, effectively preventing the pile from floating under the pressure of groundwater.

[0044] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0045] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. An anti-float pile shoe, characterized in that, The pile shoe body, the anchor rod telescopic mechanism and the trigger mechanism are included. The pile shoe body includes a cylinder, a bottom sealing plate and a top sealing plate, a plurality of side through holes are arranged on the cylinder, and a bottom through hole is arranged at the center position of the bottom sealing plate. The trigger mechanism includes a vertical sleeve and a trigger rod, the bottom of the vertical sleeve is fixed with the bottom sealing plate, and the center hole of the vertical sleeve is communicated with the bottom through hole; the trigger rod is arranged in the vertical sleeve and can move up and down along the vertical sleeve, the both ends of the trigger rod are respectively extended from the vertical sleeve, the bottom is provided with an end plate, and the top is provided with a chuck; a rotating disc is sleeved on the vertical sleeve, and the rotating disc can rotate around the vertical sleeve; The anchor rod telescopic mechanism includes a positioning cylinder, an anchor rod, a spring and a steel strand; one end of the positioning cylinder is fixed with the cylinder, and the center hole of the positioning cylinder is communicated with the side through hole; the anchor rod is arranged in the positioning cylinder, one end of the anchor rod faces the outside of the cylinder, and the other end is provided with the spring; one end of the steel strand is wound on the rotating disc, and the other end is fixedly connected with the end of the anchor rod; Rotating the rotating disc can make the anchor rod retreat into the positioning cylinder and make the spring store energy, and the downward movement of the trigger rod along the vertical sleeve can make the chuck and the rotating disc fixed, and limit the rotation of the rotating disc; when the end plate is subjected to upward force, the upward movement of the trigger rod along the vertical sleeve can make the chuck and the rotating disc separate, and the rotating disc can rotate again, and the one end of the anchor rod can be shot out of the side through hole under the pushing of the spring; The chuck is provided with a first positioning block and a second positioning block, the top of the vertical sleeve is provided with a first positioning groove matched with the first positioning block, and the top of the rotating disc is provided with a second positioning groove matched with the second positioning block; when the first positioning block is located in the first positioning groove and the second positioning block is located in the second positioning groove, the chuck is fixed with the vertical sleeve and the rotating disc; The one end of the positioning cylinder facing the rotating disc is downwardly inclined, and the included angle between the positioning cylinder and the horizontal plane is α, and 5°≤α≤30°.

2. The anti-floating pile shoe according to claim 1, wherein The inner diameter of the positioning cylinder is D1, a sliding groove is arranged in the positioning cylinder, the diameter of the sliding groove is D2, the diameter of the anchor rod is D3, the one end of the anchor rod connected with the steel strand is an enlarged end, the diameter of the enlarged end of the anchor rod is D4, and D3 3. A method of preventing the floating of reinforcement cages, characterized in that, The anti-floating pile shoe according to claim 1 or 2, and the steel reinforcement cage anti-floating method comprises the following steps: Step one, the chuck and the rotating disc are in a separated state, the rotating disc is rotated to wind the steel strand on the rotating disc, the steel strand pulls the anchor rod to retreat into the positioning cylinder and compresses the spring to store energy, then the chuck and the rotating disc are buckled together, and the rotating disc is limited to rotate; Step two, the anti-floating pile shoe is installed at the bottom of the steel reinforcement cage, when the steel reinforcement cage is lowered to the bottom of the pile hole, the end plate is subjected to a pushing force, the trigger rod moves upward relative to the vertical sleeve, the chuck and the rotating disc are separated, the anchor rod is rapidly shot out of the positioning cylinder under the pushing of the spring and inserted into the soil at the side of the pile hole.

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