A pile end mechanism of a precast pile and a precast pile

Abstract

The utility model discloses a pile end mechanism of precast pile, including end plate (2), the edge fixed setting of end plate (2) has the enclosure (3) that extends vertically upwards, all enclosure (3) form together cylinder shape, the pile end mechanism is in the use state, the enclosure (3) is located the periphery of precast pile main part (1). The utility model is further related to a kind of precast pile. The utility model compared to prior art, on the one hand, it is favorable to avoid that grouting passage is blocked, ensure that the grouting from precast pile main part inside to pile hole is carried out smoothly, on the other hand, it is favorable to improve the stability of pile hole wall, prevent the collapse of hole wall, improve the application range of precast pile.

Description

Technical Field

[0001] This utility model relates to a pile end mechanism for a precast pile and a precast pile, belonging to the field of precast pile foundation engineering technology. Background Technology The traditional precast pile installation process mainly includes the following steps: 1. Drilling to the designed depth using mechanical drilling equipment; 2. Injecting cement grout, cement mortar, or fine stone concrete (collectively referred to as grout) into the lower half of the hole; 3. Inserting the precast pile into the hole, with the diameter of the precast pile slightly smaller than the diameter of the drilled hole, and the mortar in the hole filling the gap between the precast pile and the hole wall under the pressure of the precast pile; 4. Pressing or hammering the precast pile into the bearing layer at the bottom of the hole using pile driving machinery.

[0002] The bearing capacity of precast piles relies primarily on two aspects: the end bearing (base bearing) resistance and the friction between the pile's side surface and the borehole wall. Current technology uses mechanical drilling equipment, which results in only circular holes, and since precast piles are also circular, the limited surface area of ​​the pile leads to relatively low friction between the pile's side surface and the borehole wall, failing to fully utilize the pile's bearing capacity. Furthermore, in softer soils, the drilled holes are prone to collapse, necessitating repeated drilling operations and hindering construction efficiency. Simultaneously, the use of mechanical drilling equipment and the removal of excavated soil not only increases construction steps but also raises costs.

[0003] To address the aforementioned technical problems, the inventor's prior patent application (application number 2024231343685) disclosed a novel precast pile. Its pile end mechanism mainly includes an end plate and a sleeve. The area of ​​the end plate is larger than the cross-sectional area of ​​the sleeve. Several through holes are provided on the side wall of the sleeve. Grout from inside the pile body is injected into the gap between the pile body and the pile hole through these through holes (grouting holes). During precast pile construction, the pile end mechanism is fixed to the lower end of the precast pile body, that is, the upper end of the sleeve is welded to the lower end of the precast pile body. However, this solution has the following shortcomings in practical use: For foundations with soft soil, during pile driving, the soil on the side wall of the pile hole may crowd towards the through holes (grouting holes), blocking them and leading to grouting failure or insufficient grouting. Therefore, this solution requires further improvement. Utility Model Content

[0004] This utility model provides a pile end mechanism and a precast pile, which helps to avoid the grouting channel being blocked and improves the stability of the borehole wall. The specific technical solution is as follows.

[0005] A pile end mechanism for a precast pile includes an end plate, characterized in that a vertically upward extending surrounding plate is fixedly provided on the edge of the end plate, and all the surrounding plates together form a cylindrical shape; when the pile end mechanism is in use, the surrounding plate is located on the periphery of the precast pile body.

[0006] By adopting the above technical solution, after the end plate of the pile end mechanism is fixed to the precast pile body, the end plate is roughly horizontal and the surrounding plate is roughly vertical during the pile driving process. The grouting channel at the lower end of the precast pile body is protected by the surrounding plate. Even in softer foundations, the grouting channel can be prevented from being blocked. At the same time, all the surrounding plates together form a cylindrical shape, which has a certain supporting effect on the pile hole wall formed by the pile driving, which is conducive to improving the stability of the hole wall and preventing the hole wall from collapsing.

[0007] Furthermore, the end plate is a circular plate or a polygonal plate. Preferably, the end plate is a hexagonal star-shaped plate. Compared with a circular end plate, the circumference of a polygonal plate (a hexagonal star-shaped plate is a type of polygonal plate) is significantly increased, thereby increasing the borehole wall area and thus improving the friction between the precast pile and the borehole wall.

[0008] Furthermore, the upper surface of the end plate has a groove; in use, the groove connects the hollow cavity of the precast pile body and the gap between the precast pile body and the surrounding plate. That is, the groove acts as a grouting channel, allowing the grout inside the precast pile body to flow into the gap between the precast pile body and the surrounding plate through the groove, and then fill the gap between the precast pile body and the borehole wall.

[0009] Furthermore, a rib is provided below the end plate, the rib being perpendicular to the end plate and fixedly connected to it; preferably, four ribs are radially distributed below the end plate. By providing the ribs, the rigidity of the end plate is improved, which helps prevent or reduce bending; furthermore, the generally vertical ribs help ensure that the entire precast pile remains vertical when pressed into the soil, preventing or reducing tilting. Preferably, the lower outer end of the rib is chamfered.

[0010] Furthermore, a grouting box is provided on the rib plate, and the inner cavity of the grouting box is open to the upper surface of the end plate; in use, the inner end of the grouting box is connected to the hollow cavity of the precast pile body, and the outer end of the grouting box is connected to the gap between the precast pile body and the surrounding plate.

[0011] Based on the same inventive concept, this utility model also relates to a precast pile, characterized in that it includes a precast pile body and the aforementioned pile end mechanism, the precast pile body is fixedly connected to the end plate, and the surrounding plate is located on the periphery of the lower end of the precast pile body; the precast pile body has a hollow cavity, and there is a gap between the precast pile body and the surrounding plate, and the gap and the hollow cavity are connected through a grouting channel.

[0012] Furthermore, the grouting channel is a through hole located at the lower end of the precast pile body; or the grouting channel is a notch located at the lower edge of the precast pile body; or the grouting channel is a groove located on the upper surface of the end plate, the groove connecting the hollow cavity of the precast pile body and the gap between the precast pile body and the surrounding plate.

[0013] Furthermore, a rib is fixedly provided below the end plate, and the rib is perpendicular to the end plate; the grouting channel is a grouting box provided on the rib, and the inner cavity of the grouting box is open to the upper surface of the end plate; the inner end of the grouting box is connected to the hollow cavity, and the outer end of the grouting box is connected to the gap.

[0014] Furthermore, a number of pads are fixedly provided on the upper surface of the end plate, the precast pile body is fixedly connected to the pads, and the channel between adjacent pads forms the grouting channel.

[0015] Preferably, the enclosure plate is fixedly connected to the precast pile body via a connector. This arrangement aims to form a unified structure with the enclosure plate, precast pile body, and end plate, increasing the rigidity of the end plate and helping to prevent excessive deformation during pile driving. The connector can be a connecting block or connecting plate, etc., and can be fixed to the enclosure plate and precast pile body by welding.

[0016] Furthermore, when the end plate is a polygonal plate, multiple surrounding plates are fixedly provided along the edge of the end plate, and at least some adjacent surrounding plates are connected by reinforcing plates located on the inner side of the surrounding plates. By providing these reinforcing plates, the lateral stiffness of the overall surrounding plate can be improved, which is beneficial for reducing the thickness of the surrounding plate and saving steel consumption.

[0017] Compared with the prior art, this invention helps to avoid the grouting channel from being blocked, ensuring the smooth grouting from the inside of the precast pile body into the pile hole; on the other hand, it helps to improve the stability of the pile hole wall, prevent the collapse of the hole wall, and expand the applicability of precast piles. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the pile end mechanism of Embodiment 1 of this utility model; Figure 2 This is a top view schematic diagram of the precast pile of Embodiment 1 of this utility model; Figure 3 This is a bottom view schematic diagram of the precast pile of Embodiment 1 of this utility model; Figure 4 This is a cross-sectional schematic diagram of the precast pile of Embodiment 1 of this utility model; Figure 5 This is a construction schematic diagram of the precast pile according to Embodiment 1 of this utility model; Figure 6 This is a cross-sectional schematic diagram of the precast pile of Embodiment 2 of this utility model; Figure 7 This is a cross-sectional schematic diagram of the precast pile of Embodiment 3 of this utility model; Figure 8 This is a top view schematic diagram of the precast pile of Embodiment 3 of this utility model; Figure 9 This is a cross-sectional schematic diagram of the precast pile of Embodiment 4 of this utility model; Figure 10 This is a top view schematic diagram of the precast pile of Embodiment 4 of this utility model; Figure 11 This is a top view schematic diagram of the precast pile of Embodiment 5 of this utility model; Figure 12 This is a bottom view of the precast pile of Embodiment 5 of this utility model; Figure 13 yes Figure 12 Sectional view of section AA; Figure 14 This is a schematic diagram of the rib plate and grouting box of the pile end mechanism in Embodiment 5 of this utility model; Figure 15 This is a top view schematic diagram of the pile end mechanism of Embodiment 6 of this utility model.

[0019] In the figure: 1. Precast pile body, 1.1. Hole, 1.2. Through hole, 1.3. End plate, 2. Groove, 2.1. Surrounding plate, 3. Void, 4. Pile hole, 5. Rib plate, 6. Pile driving machine, 7. Pad block, 8. Channel, 8.1. Connector, 9. Grouting box, 10. Reinforcing plate. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings.

[0021] Example 1 See Figures 1-5 Precast piles include a precast pile body 1 and a pile end mechanism. The precast pile body 1 can be a steel pipe pile body or a precast concrete pile body. The steel pipe pile body is a pile made of steel pipes, and the precast concrete pile body is made of reinforced concrete. It usually has a metal base plate at its lower end to facilitate production and subsequent connection. The pile end mechanism includes an end plate 2 and a surrounding plate 3. The edge of the end plate 2 is fixedly provided with a vertically upward extending surrounding plate 3, and all the surrounding plates 3 together form a cylindrical shape. The precast pile body 1 is fixedly connected to the end plate 2. The precast pile body 1 is above the end plate 2, and the surrounding plate 3 is located on the outer periphery of the lower end of the precast pile body 1. The precast pile body 1 and the end plate 2 can be fixedly connected by welding, fasteners, etc. They can be connected and fixed on the construction site or in the prefabrication plant. The precast pile body 1 has a hollow cavity 1.1, and there is a gap 4 between the precast pile body 1 and the surrounding plate 3. The gap 4 and the hollow cavity 1.1 are connected through a grouting channel.

[0022] In this embodiment, the grouting channel is a groove 2.1 set on the upper surface of the end plate 2. The groove 2.1 connects the hollow cavity 1.1 of the precast pile body 1 and the gap 4 between the precast pile body 1 and the surrounding plate 3. That is, the inner end of the groove 2.1 corresponds to the hollow cavity 1.1 and the outer end of the groove 2.1 corresponds to the gap 4.

[0023] like Figure 2 , Figure 3 As shown, the end plate 2 is a hexagonal star-shaped plate, but those skilled in the art will understand that the end plate 2 can be a circular plate or a polygonal plate (the hexagonal star-shaped plate is a type of polygonal plate). The polygonal end plate 2 has a significantly increased perimeter compared to the circular end plate 2, thereby increasing the hole wall area of ​​the pile hole 5 and thus improving the friction between the precast pile and the hole wall.

[0024] Preferably, a rib plate 6 is provided below the end plate 2, the rib plate 6 is perpendicular to the end plate 2, and the rib plate 6 is fixedly connected to the end plate 2; preferably, four rib plates 6 are radially distributed below the end plate 2. By providing the rib plates 6, on the one hand, the rigidity of the end plate 2 is improved, which helps to prevent or reduce the bending of the end plate 2; on the other hand, the generally vertical rib plates 6 help to ensure that the entire precast pile remains vertical when pressed into the soil, preventing or reducing the tilting of the precast pile. Preferably, the lower outer end of the rib plate 6 is chamfered.

[0025] Using the technical solution of this utility model, it is only necessary to fix the pile end mechanism to the lower end of the precast pile body 1, without making any modifications to the existing precast pile body 1. The precast pile is pressed into the soil using the pile driving machine 7. Since the area of ​​the end plate 2 (the surrounding plate 3 is on the periphery of the precast pile body 1) is larger than the cross-sectional area of ​​the precast pile body 1, the end plate 2 is squeezed out of the soil during the pressing process, thereby forming a pile hole 5 with a cross-sectional area larger than that of the precast pile body 1. At the same time, grout (not shown) is placed in the hollow cavity 1.1 of the precast pile body 1. As the precast pile is continuously pressed into the soil, the grout flows from the hollow cavity 1.1 through the groove 2.1 (grouting channel) into the gap 4 between the precast pile body 1 and the surrounding plate 3, and then fills the space between the precast pile body 1 and the hole wall (e.g., Figure 4 , Figure 5 As shown in the figure, after the grout solidifies, the outer surface of the precast pile body 1 forms a large frictional fixing force between the grout and the soil, thereby improving the bearing capacity of the precast pile. In order to inject grout into the hollow cavity 1.1 of the precast pile body 1, conventional methods such as setting grouting holes on the top side wall of the precast pile body 1 can be used.

[0026] It should be noted that the directions such as below, above, and vertical in this embodiment are based on the usage state.

[0027] Example 2 like Figure 6 As shown, the main difference between Embodiment 2 and Embodiment 1 is that the grouting channel in Embodiment 2 includes a through hole 1.2 located at the lower end of the precast pile body 1 and a notch 1.3 located at the lower edge of the precast pile body 1. Those skilled in the art will understand that the grouting channel can also be either the through hole 1.2 or the notch 1.3. Grout can flow from the hollow cavity 1.1 through the through hole 1.2 and / or the notch 1.3 (grouting channel) into the gap 4 between the precast pile body 1 and the surrounding plate 3. In Embodiment 1, the groove 2.1 is provided on the upper surface of the end plate 2, requiring a relatively thick end plate 2. In Embodiment 2, since the groove 2.1 is not required on the upper surface of the end plate 2, the thickness of the end plate 2 can be reduced, which is beneficial for saving steel consumption.

[0028] Example 3 like Figure 7 , Figure 8 As shown, the main difference between Embodiment 3 and Embodiment 1 is that: several pads 8 are fixedly installed on the upper surface of the end plate 2, the precast pile body 1 is fixedly connected to the pads 8, and the channel 8.1 between adjacent pads 8 forms a grouting channel. Grout can flow from the hollow cavity 1.1 through the channel 8.1 (grouting channel) between adjacent pads 8 into the gap 4 between the precast pile body 1 and the surrounding plate 3. By setting the pads 8, it is not necessary to set the groove 2.1 on the upper surface of the end plate 2 (the scheme of Embodiment 1), nor is it necessary to set the through hole 1.2 or notch 1.3 at the lower end of the precast pile body 1 (the scheme of Embodiment 2), which is beneficial to reduce the thickness of the end plate 2 and simplify the processing requirements of the precast pile body 1.

[0029] Example 4 like Figure 9 , Figure 10 As shown, the main difference between Embodiment 4 and Embodiment 1 is that the rib plate 6 in Embodiment 1 is removed, and the surrounding plate 3 is fixedly connected to the precast pile body 1 via the connector 9. This arrangement aims to make the surrounding plate 3, the precast pile body 1, and the end plate 2 form a single unit, increasing the rigidity of the end plate 2 and helping to prevent excessive deformation during pile driving. In some cases, the rib plate 6 in Embodiment 1 can be omitted due to the increased rigidity of the end plate 2 (which helps reduce steel consumption). The connector 9 can be a connecting block or a connecting plate, etc., and can be fixed to the surrounding plate 3 and the precast pile body 1 by welding.

[0030] Example 5 like Figures 11-14As shown, the main difference between Example 5 and Example 1 is that the grouting channel is a grouting box 10 installed on the rib plate 6, and the inner cavity of the grouting box 10 is open towards the upper surface of the end plate 2 (of course, the end plate 2 has an opening connecting the inner cavity of the grouting box 10 and the upper surface of the end plate 2); the inner end of the grouting box 10 is connected to the hollow cavity 1.1, and the outer end of the grouting box 10 is connected to the gap 4, and the inner ends of some adjacent grouting boxes 10 can be connected. Grout can flow from the hollow cavity 1.1 through the inner and outer ends of the grouting box 10 (grouting channel) into the gap 4 between the precast pile body 1 and the surrounding plate 3. The entire inner cavity of the grouting box 10 can be open towards the upper surface of the end plate 2. Figure 11 The illustration only shows that the inner and outer ends of the grouting box 10 are open to the upper surface of the end plate 2. This avoids the end plate 2 having an excessively large opening area corresponding to the inner cavity of the grouting box 10, which would affect the rigidity of the end plate. The grouting box 10 serves as a grouting channel and also enhances the structural strength of the rib plate 6 and the end plate 2, which helps to reduce the thickness of the rib plate 6 and the end plate 2 and saves steel. At the same time, it eliminates the need to set a through hole 1.2 or a notch 1.3 at the lower end of the precast pile body 1 (as in the scheme of embodiment 2), which simplifies the processing requirements of the precast pile body 1.

[0031] Example 6 like Figure 15 As shown, the main difference between Embodiment 6 and Embodiment 1 is that when the end plate 2 is a polygonal plate, multiple surrounding plates 3 are fixedly provided on the edge of the end plate 2. Figure 15 The end plate 2 shown in the diagram is a hexagonal star-shaped plate, and there are 12 surrounding plates 3. At least some adjacent surrounding plates 3 are connected by reinforcing plates 11, which are located on the inner side of the surrounding plates 3. By setting these reinforcing plates 12, the lateral stiffness of the overall surrounding plates 3 can be improved, which is beneficial to reducing the thickness of the surrounding plates 3 and saving steel.

[0032] The embodiments of the present invention have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention is not limited to the specific embodiments described above; these embodiments are merely illustrative and not limiting. Those skilled in the art, under the guidance of the present invention, can make many modifications without departing from the spirit and scope of the claims, and all such modifications fall within the protection scope of the present invention.

Claims

1. A pile tip mechanism for a precast pile, comprising an end plate (2), characterized in that, The edge of the end plate (2) is fixedly provided with a vertically extending surrounding plate (3), and all the surrounding plates (3) together form a cylindrical shape; when the pile end mechanism is in use, the surrounding plate (3) is located on the periphery of the precast pile body (1).

2. A pile tip mechanism for a precast pile according to claim 1, characterised in that, The end plate (2) is a circular plate or a polygonal plate.

3. A pile tip mechanism for a precast pile according to claim 1, characterised in that, The upper surface of the end plate (2) has a groove (2.1); in use, the groove (2.1) connects the hollow cavity (1.1) of the precast pile body (1) and the gap (4) between the precast pile body (1) and the surrounding plate (3).

4. A pile tip mechanism for a precast pile according to claim 1, characterised in that, A rib plate (6) is fixedly provided below the end plate (2), and the rib plate (6) is perpendicular to the end plate (2); a grouting box (10) is provided on the rib plate (6), and the inner cavity of the grouting box (10) is open to the upper surface of the end plate (2); in the use state, the inner end of the grouting box (10) is connected to the hollow cavity (1.1) of the precast pile body (1), and the outer end of the grouting box (10) is connected to the gap (4) between the precast pile body (1) and the surrounding plate (3).

5. A precast pile, characterized in that The precast pile body (1) and the pile end mechanism as described in any one of claims 1-4 are included. The precast pile body (1) is fixedly connected to the end plate (2), and the surrounding plate (3) is located on the periphery of the lower end of the precast pile body (1). The precast pile body (1) has a hollow cavity (1.1), and there is a gap (4) between the precast pile body (1) and the surrounding plate (3). The gap (4) and the hollow cavity (1.1) are connected through a grouting channel.

6. A preform pile according to claim 5, characterised in that, The grouting channel is a through hole (1.2) at the lower end of the precast pile body (1); or the grouting channel is a notch (1.3) at the lower edge of the precast pile body (1); or the grouting channel is a groove (2.1) on the upper surface of the end plate (2), the groove (2.1) connecting the hollow cavity (1.1) of the precast pile body (1) and the gap (4) between the precast pile body (1) and the surrounding plate (3).

7. A preform pile according to claim 5, characterised in that, A rib (6) is fixedly provided below the end plate (2), and the rib (6) is perpendicular to the end plate (2); the grouting channel is a grouting box (10) provided on the rib (6), and the inner cavity of the grouting box (10) is open to the upper surface of the end plate (2); the inner end of the grouting box (10) is connected to the hollow cavity (1.1), and the outer end of the grouting box (10) is connected to the gap (4).

8. The precast pile according to claim 5, characterized in that, A number of pads (8) are fixedly provided on the upper surface of the end plate (2). The precast pile body (1) is fixedly connected to the pads (8). The channel (8.1) between adjacent pads (8) forms the grouting channel.

9. The precast pile according to claim 5, characterized in that, The enclosure (3) is fixedly connected to the precast pile body (1) via a connector (9).

10. The precast pile according to claim 5, characterized in that, When the end plate (2) is a polygonal plate, a plurality of the surrounding plates (3) are fixedly provided on the edge of the end plate (2), and at least some of the adjacent surrounding plates (3) are connected by a reinforcing plate (11), which is located inside the surrounding plate (3).

Images