PHC tubular pile capable of improving connecting strength with bearing platform

Abstract

The utility model discloses a PHC (Prestressed High-strength Concrete) tubular pile capable of improving the connecting strength with a bearing platform. The PHC tubular pile comprises high-strength concrete, prestressed reinforcements and spiral stirrups, wherein the high-strength concrete is of a tubular structure; the prestressed steel bars are arranged in the pipe wall of the high-strength concrete in parallel in a circular array mode. The multiple spiral stirrups are spirally arranged in the pipe wall of the high-strength concrete and located on the outer sides of the multiple prestressed steel bars. The device relates to the technical field of pipe piles, the connection strength between the PHC pipe pile and the bearing platform is improved, the risk of connection failure is avoided, and the safety of a bearing platform pile foundation is guaranteed. And the extending parts of the transverse steel bars penetrate into the core filling concrete, so that the bonding area is increased, and the bonding force is improved. Due to the design of the length and the arrangement distance of the transverse steel bars, the stress distribution can be optimized, and the bending resistance and the shearing resistance of the structure are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of pipe piles, in particular to a PHC pipe pile with improved connection strength with a bearing platform. Background Art

[0002] In the prior art, the pile caps widely used in wind turbine foundations typically employ PHC pipe piles or cast-in-place piles. The connection between the PHC pipe piles and the cap primarily relies on the bond between the core-fill concrete and the inner wall of the pipe piles. This connection method provides sufficient connection strength under normal operating conditions, ensuring the safety and stability of the cap pile foundation. However, when the pull-out force transmitted from the foundation cap to the pipe pile exceeds the bond between the core-fill concrete and the inner wall of the pipe pile, the connection may fail, affecting the performance and safety of the cap pile foundation.

[0003] While the existing PHC pile-to-cap connection can meet engineering requirements in most situations, it can be severely tested under extreme or abnormal operating conditions, such as high winds, earthquakes, and other natural disasters. In particular, when the pullout force exceeds the bond strength, the risk of connection failure increases, potentially damaging the entire cap pile foundation and affecting the safe operation of the wind turbine. Therefore, the existing connection methods may have certain deficiencies when faced with extreme conditions, requiring further technical improvements and innovations to enhance the connection strength between the pile and the cap, ensuring the safety and reliability of the cap pile foundation under various operating conditions. Utility Model Content

[0004] The purpose of the utility model is to provide a PHC pipe pile with improved connection strength with a cap, so as to solve the problems raised in the background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a PHC pipe pile with improved connection strength with a foundation cap, comprising: high-strength concrete, the high-strength concrete is arranged in a tubular structure, and the end portion is connected to the foundation cap; prestressed steel bars, a plurality of the prestressed steel bars are arranged in parallel in a circular array in the pipe wall of the high-strength concrete; spiral stirrups, a plurality of the spiral stirrups are arranged in a spiral shape in the pipe wall of the high-strength concrete, and are located on the outside of the plurality of the prestressed steel bars; transverse steel bars, a plurality of the transverse steel bars are horizontally welded to the spiral stirrups, and the other ends extend to the inner side of the high-strength concrete pipe wall.

[0006] In a feasible implementation manner, the diameter of the plurality of transverse steel bars is not greater than the diameter of the spiral stirrups, and the plurality of transverse steel bars extend out of the inner side of the high-strength concrete tube wall.

[0007] In a feasible implementation manner, a plurality of the transverse steel bars are arranged at intervals from a plurality of the prestressed steel bars, and the arrangement of the plurality of the transverse steel bars is uniform arrangement or plum blossom arrangement.

[0008] In a feasible implementation manner, the spiral stirrups are arranged longitudinally on the inner wall of the high-strength concrete.

[0009] In a feasible embodiment, an end plate is provided inside the high-strength concrete, and the gap between the end plate, the high-strength concrete 1 and the foundation pedestal is filled with core-filled concrete. Core-filled concrete stirrups are also provided on the outside of the core-filled concrete, and anchor steel bars are also provided between the foundation pedestal and the core-filled concrete.

[0010] In a feasible implementation manner, the longitudinal arrangement spacing of the plurality of transverse steel bars is consistent with the spacing of the longitudinally arranged spiral stirrups, and the transverse steel bars are only arranged within 3 m of one end of the high-strength concrete tube wall 1 .

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: the present device increases the bonding strength between the PHC pipe pile and the core-fill concrete by adding transverse steel bars extending out to a certain length on the inner wall of the PHC pipe pile, and the arrangement of the transverse steel bars is spaced apart from the prestressed steel bars and spiral stirrups, and maintains a longitudinal arrangement spacing of 100mm with the spiral stirrups within 3 meters of one end of the high-strength concrete pile head. The connection strength between the PHC pipe pile and the pedestal is improved, the risk of connection failure is avoided, and the safety of the pedestal pile foundation is ensured. The protruding part of the transverse steel bar penetrates deep into the core-fill concrete, increasing the bonding area and thus improving the bonding strength. The design of the length and arrangement spacing of the transverse steel bars helps to optimize the distribution of stress, improve the bending and shearing resistance of the structure, and further enhance the overall performance and stability of the structure. While improving the connection strength, the present invention also takes into account the economy and convenience of construction, providing long-term and stable safety guarantees for large-scale engineering structures such as wind turbines. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural diagram of the utility model;

[0013] Figure 2 It is a cross-sectional schematic diagram of the present utility model;

[0014] Figure 3 This is a cross-sectional diagram of the uniform arrangement of transverse reinforcement bars of the present invention;

[0015] Figure 4 It is a cross-sectional expansion diagram of the plum blossom-shaped arrangement of the transverse reinforcement of the present invention;

[0016] Figure 5 This is a schematic diagram of the connection between the utility model and the bearing platform;

[0017] Figure 6 It is a cross-sectional schematic diagram of the connection between the utility model and the bearing platform.

[0018] In the figure: 1. High-strength concrete, 2. Prestressed steel bars, 3. Spiral stirrups, 4. Transverse steel bars, 5. Foundation cap, 6. Core-fill concrete, 7. Anchor steel bars, 8. Core-fill concrete stirrups, 9. End plate. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] See also Figures 1 to 6 The utility model provides a technical solution: a PHC pipe pile with improved connection strength with a foundation cap, comprising: high-strength concrete 1, prestressed steel bars 2 and spiral stirrups 3, the high-strength concrete 1 is configured as a tubular structure, and the end portion is connected to the foundation cap 5; a plurality of prestressed steel bars 2 are arranged in parallel in a circular array in the pipe wall of the high-strength concrete 1; a plurality of spiral stirrups 3 are spirally arranged in the pipe wall of the high-strength concrete 1 and are located on the outside of the plurality of prestressed steel bars 2; transverse steel bars 4, a plurality of transverse steel bars 4 are horizontally welded to the spiral stirrups 3, and the other ends extend to the inner side of the pipe wall of the high-strength concrete 1.

[0021] In the specific implementation process, it should be noted that the high-strength concrete 1 is a tubular structure, which serves as the main part of the pipe pile. Figure 1-2 As shown, a number of prestressed steel bars 2 are arranged in parallel in a circular array inside the tube wall of high-strength concrete 1 to enhance the pile's bearing capacity. A number of spiral stirrups 3 are arranged on the outside of the prestressed steel bars 2. On the one hand, the prestressed steel bars 2 can be positioned, and on the other hand, the shear resistance of the overall structure is improved. A number of transverse steel bars 4 are welded horizontally on the spiral stirrups 3. The other end of the transverse steel bar 4 extends to the inner side of the tube wall of high-strength concrete 1, with a length of about 140mm to 170mm and an extension distance of 70mm to 100mm. When the core-filling concrete 6 is poured into the pipe pile, the transverse steel bar 4 can effectively increase the bonding force between the PHC pipe pile and the core-filling concrete 6, thereby avoiding the risk of failure in the connection between the pipe pile and the foundation pedestal 5, and ensuring the safety performance of the pedestal pile foundation. It effectively improves the connection strength between the PHC pipe pile and the foundation pedestal 5, ensuring the stability and safety of large-scale engineering structures such as wind turbines.

[0022] In some examples, further, the diameter of several transverse steel bars 4 is not greater than the diameter of the spiral stirrups 3, and the diameter of the transverse steel bars 4 is equal to the diameter of the spiral stirrups 3; or the diameter of the transverse steel bars 4 is less than 2 mm from the diameter of the spiral stirrups 3, and the diameter of the transverse steel bars 4 is equal to or less than the diameter of the spiral stirrups 3, which can make the heat distribution during welding more uniform, reduce the problems of weak welding or excessive heat-affected zone caused by excessive diameter difference, thereby improving the overall strength and reliability of the welding point. When the diameter of the transverse steel bars 4 is similar to that of the spiral stirrups 3, stress can be transferred more evenly between the two, which helps to improve the collaborative working performance of the entire structure, so that it can more effectively resist deformation and damage when subjected to external forces. When the diameter of the transverse steel bars 4 is smaller than that of the spiral stirrups 3, more steel bars can be arranged in the same volume, increasing the contact area between the transverse steel bars 4 and the core-fill concrete 6, thereby improving the bonding force and enhancing the overall connection strength between the PHC pipe pile and the core-fill concrete 6.

[0023] In some examples, further, a plurality of transverse steel bars 4 extend out of the inner wall of the high-strength concrete 1, the transverse steel bars 4 extend out of the inner wall of the pile by about 70mm-100mm, and the length of the transverse steel bars 4 is about 140mm-170mm. Figure 5-6 As shown, after pouring the core-fill concrete 6, the transverse reinforcement 4 extending from the inner wall of the pile tightly bonds with the core-fill concrete 6, forming a strong bond, which greatly improves the connection strength between the device and the foundation cap 5. The transverse reinforcement 4 extending from the inner wall of the pile increases the contact area with the core-fill concrete 6, thereby improving the bond between the pile and the core-fill concrete 6 and making the connection more secure. The extension length and total length of the transverse reinforcement 4 ensure that there is sufficient reinforcement length to resist shear and tensile forces when subjected to pullout forces, thereby improving the connection strength between the pile and the foundation cap 5. When subjected to heavy loads, the extended transverse reinforcement 4 can effectively prevent failure of the connection between the pile and the foundation cap 5, ensuring the safety of the structure.

[0024] In some examples, further, a plurality of transverse steel bars 4 are arranged at intervals from a plurality of prestressed steel bars 2, and the arrangement of the plurality of transverse steel bars 4 is uniform or plum blossom-shaped. Figure 3-4As shown, uniform arrangement or plum blossom arrangement can improve the safety and reliability of the structure, and prevent the separation of the pipe pile and the foundation pedestal 5 by increasing the connection strength. Enhance the durability of the structure and reduce cracks and damage to the concrete by optimizing the arrangement of steel bars. Adapt to different engineering needs and meet specific structural design and construction requirements by selecting a suitable arrangement method. Uniform arrangement or plum blossom arrangement helps to improve the integrity of the pipe pile, so that the stress is more evenly distributed in the wall of the pipe pile, thereby improving the bending and shearing resistance. It helps to improve the collaborative working ability between the transverse reinforcement 4 and the prestressed reinforcement 2, and enhance the connection strength between the pipe pile and the foundation pedestal 5. It can also avoid local stress concentration caused by the concentration of reinforcement and reduce potential damage risks. At the same time, since the transverse reinforcement 4 is staggered in different directions, it helps to improve the crack resistance of the concrete and inhibit the development of cracks.

[0025] In some examples, further, the spiral stirrups 3 are arranged longitudinally on the inner wall of the high-strength concrete 1. The longitudinal arrangement spacing of the spiral stirrups 3 within 3m at both ends of the high-strength concrete 1 is 100mm, and the longitudinal arrangement spacing outside the 3m at both ends of the high-strength concrete 1 is 200mm. Within the 3-meter range at both ends of the high-strength concrete 1, the arrangement spacing of the spiral stirrups 3 is smaller (100mm), which helps to improve the stability and shear resistance of the pile end, which is crucial for bearing the large load from the foundation pedestal 5. Preferably, in the middle area of ​​the pile, the arrangement spacing of the spiral stirrups 3 is increased to 200mm, which can reduce the use of materials while maintaining the structural strength, thereby reducing costs and improving economic benefits. At both ends of the pile, due to the concentration of load, stress concentration is likely to occur. By increasing the density of the spiral stirrups 3, stress concentration can be effectively controlled to prevent local damage from affecting the safety of the overall structure. Within the 3-meter range at both ends of the high-strength concrete 1, due to the large load, higher bending resistance is required. The increased density of the spiral stirrups 3 helps to improve the bending resistance of this area, thereby improving the bending resistance of the overall structure. Different areas of the pile are subject to different loads and stresses. By using a smaller spacing within 3 meters at both ends and a larger spacing in the middle, the stress characteristics of different areas can be specifically adapted.

[0026] In some examples, further, a plurality of transverse steel bars 4 extend out of the inner wall of the high-strength concrete 1, the transverse steel bars 4 extend out of the inner wall of the pile by about 70mm-100mm, and the length of the transverse steel bars 4 is about 140mm-170mm. Figure 5-6As shown, after pouring the core-fill concrete 6, the transverse reinforcement 4 extending from the inner wall of the pile tightly bonds with the core-fill concrete 6, forming a strong bond, which greatly improves the connection strength between the device and the foundation cap 5. The transverse reinforcement 4 extending from the inner wall of the pile increases the contact area with the core-fill concrete 6, thereby improving the bond between the pile and the core-fill concrete 6 and making the connection more secure. The extension length and total length of the transverse reinforcement 4 ensure that there is sufficient reinforcement length to resist shear and tensile forces when subjected to pullout forces, thereby improving the connection strength between the pile and the foundation cap 5. When subjected to heavy loads, the extended transverse reinforcement 4 can effectively prevent failure of the connection between the pile and the foundation cap 5, ensuring the safety of the structure.

[0027] In some examples, further, an end plate 9 is provided inside the high-strength concrete 1, and the gap between the end plate 9, the high-strength concrete 1 and the foundation pedestal 5 is filled with core-filling concrete 6. Core-filling concrete stirrups 8 are also provided on the outside of the core-filling concrete 6, and anchoring steel bars 7 are also provided between the foundation pedestal 5 and the core-filling concrete 6.

[0028] During the specific implementation process, it should be noted that an end plate 9 is provided inside the high-strength concrete 1. The gap between the end plate 9, the high-strength concrete 1 and the foundation cap 5 is filled with core-fill concrete 6 to enhance the connection strength. Core-fill concrete stirrups 8 are provided on the outside of the core-fill concrete 6 to further enhance the stability and crack resistance of the core-fill concrete 6. Anchor steel bars 7 are provided to enhance the connection between the foundation cap 5 and the core-fill concrete 6, thereby improving the safety of the overall structure. The connection strength of this device is significantly improved, ensuring the safety and reliability of the cap pile foundation under various working conditions.

[0029] In some examples, further, the longitudinal arrangement spacing of several transverse steel bars 4 is consistent with the spacing of the longitudinally arranged spiral stirrups 3. The transverse steel bars 4 are only arranged within 3m of one end of the high-strength concrete 1 tube wall. The longitudinal arrangement spacing of the transverse steel bars 4 is the same as the longitudinal arrangement spacing of the spiral stirrups 3 at the pile end, both of which are 100mm. The transverse steel bars 4 are arranged longitudinally at one end of the high-strength concrete 1. Within 3 meters of one end of the high-strength concrete 1, due to the concentrated load, the arrangement spacing is reduced to 100mm, which can specifically strengthen the connection strength of the pile head and improve its shear and bending resistance. Since the end of the high-strength concrete 1 bears a large load and stress, by arranging the transverse steel bars 4 densely at the pile end, it can better adapt to the force characteristics of the pile end and improve the overall performance of the structure.

[0030] The specific construction method mainly includes the following steps:

[0031] Step 1: First, make a pipe pile reinforcement cage according to the traditional pipe pile manufacturing method, that is, weld prestressed steel bars 2 and spiral stirrups 3 into a reinforcement cage. The spacing between the spiral stirrups 3 at both ends of the reinforcement cage is 100mm, and the remaining spacing is 200mm.

[0032] Step 2: Weld the transverse reinforcement 4 to the spiral stirrups 3 according to the prescribed arrangement and spacing.

[0033] Step 3: Place the prepared steel cage into the mold and pour high-strength concrete 1 into the mold.

[0034] Step 4: Tension the prestressed steel bar 2 according to the required prestress value.

[0035] Step 5: Place the stretched pipe piles into a centrifugal tank for centrifugation, and finally form them through centrifugal molding, and then autoclave and cure them after centrifugal molding.

[0036] Step 6: The prepared PHC pile is connected to the foundation cap 5 through the core-filled concrete 6 to form a whole and bear the force together.

[0037] In the description of the present invention, it should be understood that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "two ends" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation; at the same time, unless otherwise clearly stipulated and limited, the terms "setting", "installation", "connection", "fixed installation" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0038] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A PHC pile with improved connection strength with a cap, characterized in that: include: High-strength concrete, the high-strength concrete is arranged in a tubular structure, and the end portion is connected to the foundation cap; Prestressed steel bars, a plurality of which are arranged in parallel in a circular array in the tube wall of the high-strength concrete; Spiral stirrups, a plurality of said spiral stirrups are spirally arranged in the tube wall of the high-strength concrete and are located outside the plurality of said prestressed steel bars; Transverse steel bars, several of which are welded to the spiral stirrups in a horizontal direction, and the other ends of which extend to the inner side of the high-strength concrete pipe wall.

2. A PHC pile with improved connection strength with a cap according to claim 1, characterized in that: The diameters of the plurality of transverse steel bars are not greater than the diameters of the spiral stirrups, and the plurality of transverse steel bars extend out of the inner side of the tube wall of the high-strength concrete.

3. A PHC pile with improved connection strength with a cap according to claim 1, characterized in that: The plurality of transverse steel bars are arranged at intervals from the plurality of prestressed steel bars, and the arrangement of the plurality of transverse steel bars is uniform arrangement or plum blossom arrangement.

4. A PHC pile with improved connection strength with a cap according to claim 1, characterized in that: The spiral stirrups are arranged longitudinally on the inner wall of the high-strength concrete.

5. The PHC pile with improved connection strength with the cap according to claim 1, characterized in that: An end plate is arranged inside the high-strength concrete, and the gap between the end plate, the high-strength concrete (1) and the foundation pedestal is filled with core-filling concrete. Core-filling concrete stirrups are also arranged on the outside of the core-filling concrete, and anchoring steel bars are also arranged between the foundation pedestal and the core-filling concrete.

6. The PHC pile with improved connection strength with the cap according to claim 1, characterized in that: The longitudinal arrangement spacing of the plurality of transverse steel bars is consistent with the spacing of the longitudinally arranged spiral stirrups, and the transverse steel bars are only arranged within a range of 3m at one end of the high-strength concrete 1 tube wall.

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