A reinforcing structure of a power transmission tower pile foundation

Abstract

The utility model provides a kind of reinforcing structure of power transmission tower pile foundation, including tower pile, several tower foot bolts and built-in bolt are respectively embedded above the tower pile, wherein the built-in bolt is fixedly connected with pile cover seat by nut, the outer bolt is embedded in the pipe pile body arranged around the tower pile, outer bolt passes through the corner hole of pile cover seat, and is fixedly connected with pile cover seat by nut;The utility model built-in bolt pile cover seat and tower pile, outer bolt pile cover seat corner hole and pipe pile body, form the support of "central pile+four around auxiliary pile";Pile cover seat wraps tower pile and prevents corrosion, counterbore hides nut;Pipe pile body is embedded, and construction does not need large excavation, and maintenance is easy.

Description

Technical Field

[0001] This utility model belongs to the field of foundation pile reinforcement technology, and in particular relates to a reinforcement structure for transmission tower pile foundation. Background Technology

[0002] As the core supporting facility of the power transmission network, the stability of the pile foundation of the transmission tower directly determines the safety and reliability of power transmission. Existing transmission tower pile foundations mostly adopt a "single pile + simple pile cap" structure, connecting the tower body to the pile foundation only with tower foot bolts. This approach is prone to the following technical problems during long-term use: The upper part of the tower pile protruding above the ground is directly exposed to the natural environment, making it susceptible to rainwater erosion, soil corrosion, freeze-thaw cycles, etc., which can lead to concrete spalling, steel corrosion, and weaken the foundation bearing capacity. Traditional foundations rely solely on the bearing capacity of a single pile. When encountering geological settlement (such as compression of soft soil foundations or changes in groundwater levels) or strong wind loads, the piles are prone to tilting, the towers may sway, or even foundation instability may occur. If the foundation has insufficient bearing capacity, the existing reinforcement methods require large-scale excavation of the surrounding soil, re-casting to enlarge the foundation or adding auxiliary piles. This not only has a long construction period and high cost, but also easily causes interference to the surrounding power transmission lines and geological environment.

[0003] Therefore, it is essential to invent a reinforcement structure for the pile foundation of transmission towers. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a reinforcement structure for the foundation of a transmission tower pile, including a tower pile, tower foot bolts, built-in bolts, a pile cover seat, nuts, a pipe pile body, a pipe pile, external bolts, and corner holes. Several tower foot bolts and built-in bolts are pre-embedded on the top of the tower pile. The built-in bolts are fixedly connected to the pile cover seat by the nuts. External bolts are embedded in the pipe pile bodies arranged around the tower pile. The external bolts pass through the corner holes of the pile cover seat and are fixedly connected to the pile cover seat by the nuts.

[0005] Preferably, the tower foot bolts, the internal bolts, and the external bolts are all anchor bolts, wherein the height of the tower foot bolts is higher than the height of the internal bolts, and the internal bolts are located around the tower foot bolts.

[0006] Preferably, the pile cap seat has countersunk holes that match the built-in bolts, and the corner holes at the four corners of the pile cap seat are also countersunk holes.

[0007] Preferably, a pipe pile body is provided at the lower corner of each of the four corners of the pile cover base. The pipe pile body is pre-embedded in the ground and protrudes outward at the upper end. Concrete is poured inside the pipe pile body to form the pipe pile.

[0008] Preferably, each of the pipe piles formed inside the pipe pile body has an external bolt pre-embedded on it corresponding to the corner hole, and the pile cover seat is fixedly connected to the internal bolt and the external bolt by a nut.

[0009] Preferably, the pile cap covers the portion of the upper end of the tower pile that protrudes above the ground, and the size of the pile cap is larger than the size of the protruding end face of the tower pile.

[0010] Compared with the prior art, the present invention has the following beneficial effects: This utility model uses built-in bolts to tightly fix the pile cap seat to the tower pile, ensuring the integration of the upper end of the tower pile with the pile cap seat; external bolts pass through the corner holes of the pile cap seat and connect to the pipe pile body. By utilizing the pre-embedded support of the pipe pile body, the tower load is distributed to the tower pile and the pipe pile body, forming a composite support structure of "central pile + surrounding auxiliary piles", which significantly improves the foundation's resistance to settlement and lateral displacement, and can be adapted to the needs of transmission towers with larger loads.

[0011] This utility model of pile cap seat completely covers the upper part of the tower pile that protrudes above the ground, isolating rainwater and soil corrosive media from direct contact with the pile body, and preventing concrete peeling and steel corrosion. At the same time, the countersunk hole (suitable for internal bolts) and corner hole (suitable for external bolts) opened in the pile cap seat can hide the nut inside the hole.

[0012] This utility model adopts a pre-embedded design for the pipe pile body. During construction, it is only necessary to pre-set the pipe pile body around the tower pile and pour concrete to form the pipe pile, without the need for large-area excavation. During subsequent maintenance, the stability of the foundation can be quickly judged by checking the connection status of the pile cap and bolts. If reinforcement is required, only the bolts need to be replaced or the concrete of the pipe pile body needs to be added, which reduces the construction difficulty and maintenance cost. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0014] Figure 2 This is a partial cross-sectional structural diagram of the present invention.

[0015] Figure 3 This is a schematic diagram of the structure of the pile cover base of this utility model before installation.

[0016] In the picture: 1. Tower pile, 2. Tower foot bolt, 3. Internal bolt, 4. Pile cover seat, 5. Nut, 6. Pipe pile body, 7. Pipe pile, 8. External bolt, 9. Corner hole. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0018] In the description of the embodiments, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of the utility model, it should be noted that unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" 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 a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in the present utility model based on the specific circumstances.

[0019] As attached Figure 1 To be continued Figure 3 As shown: This utility model provides a reinforcement structure for a transmission tower foundation, including a tower pile 1, tower foot bolts 2, internal bolts 3, a pile cover seat 4, nuts 5, a pipe pile body 6, a pipe pile 7, external bolts 8, and corner holes 9. Several tower foot bolts 2 and internal bolts 3 are pre-embedded on the top of the tower pile 1. The internal bolts 3 are fixedly connected to the pile cover seat 4 by the nuts 5. External bolts 8 are embedded in the pipe pile body 6 arranged around the tower pile 1. The external bolts 8 pass through the corner holes 9 of the pile cover seat 4 and are fixedly connected to the pile cover seat 4 by the nuts 5.

[0020] Furthermore, the tower foot bolts 2, the internal bolts 3, and the external bolts 8 are all anchor bolts conforming to the GB / T799-2016 standard, made of Q235B low-carbon steel (or 45# tempered steel depending on load requirements). All bolt surfaces are hot-dip galvanized to enhance corrosion resistance. The design height of the tower foot bolts 2 is 50-80mm higher than that of the internal bolts 3, with the specific height difference determined by the thickness of the bottom connecting plate of the transmission tower body. The tower foot bolts 2 must penetrate the connecting plate and retain sufficient length for double-nut tightening, while the internal bolts 3 only need to meet the connection requirements with the pile cap 4. The internal bolts 3 are evenly distributed in a ring around the outer periphery of the tower foot bolts 2, with 4-6 bolts (matching the number of tower foot bolts 2, typically 1.5 times the number of tower foot bolts). The distance between the axis of the internal bolts 3 and the axis of the tower foot bolts 2 is controlled at 100-150mm, avoiding interference between bolt groups and creating uniform constraint on the upper end of the tower pile 1 through the ring distribution.

[0021] Furthermore, the top of the pile cap 4 is provided with countersunk holes corresponding to the built-in bolts 3 one by one. The diameter of the countersunk hole is 2-4mm larger than the diameter of the screw of the built-in bolt 3 (to ensure that the bolt can be inserted smoothly), and the depth of the countersunk hole is 1-2mm larger than the thickness of the matching nut 5 (to ensure that the nut 5 is completely sunk into the hole and to avoid exposure to rainwater erosion). At the same time, the corner holes 9 opened at the four corners of the pile cap 4 are also countersunk hole structures. The diameter of the corner holes 9 is adapted to the diameter of the screw of the external bolt 8 (the gap is controlled at 1-3mm), the depth of the countersunk hole is consistent with the depth of the countersunk hole corresponding to the built-in bolt, and the central axis of the corner holes 9 coincides with the central axis of the pipe pile body 6, ensuring that the external bolt 8 can accurately penetrate the corner holes 9 and connect with the pipe pile 7.

[0022] Furthermore, a pipe pile body 6 is set at each of the four corners of the pile cap base 4. The pipe pile body 6 is made of PHC prestressed high-strength concrete pipe pile. The pipe pile body 6 is pre-embedded in the ground using the static pressure method. The pre-embedding depth is determined according to the geological survey report (not less than 3m in soft soil foundation and not less than 2m in hard soil foundation). The upper end of the pipe pile body 6 protrudes 50-100mm from the ground (the protrusion height is consistent with the upper end of the tower pile 1 protruding from the ground). The outer wall of the protruding part is roughened (applied with interface agent) so as to bond more tightly with the concrete at the bottom of the pile cap base 4. C35 commercial concrete (slump 180±20mm) is poured inside the pipe pile body 6 to form a pipe pile 7. The top of the pipe pile 7 is flush with the upper end of the pipe pile body 6, providing a stable pre-embedded foundation for the external bolts 8.

[0023] Furthermore, an external bolt 8 is pre-embedded on the pipe pile 7 formed inside each pipe pile body 6. The pre-embedded position of the external bolt 8 corresponds precisely to the corner holes 9 at the four corners of the pile cover seat 4. During pre-embedding, the lower end of the external bolt 8 is first welded and fixed to the steel reinforcement skeleton inside the pipe pile 7. The length of the upper end of the external bolt 8 extending beyond the top of the pipe pile 7 is 30-50mm greater than the thickness of the pile cover seat 4 (to meet the double nut tightening requirements). When installing the pile cover seat 4, its bottom is first attached to the upper end of the tower pile 1 and the upper end of the pipe pile body 6, so that the internal bolt 3 is inserted into the corresponding countersunk hole and the external bolt 8 is inserted into the corresponding corner hole 9. Then, hexagonal nuts 5 of M20-M24 specifications are used to tighten the internal bolt 3 and the external bolt 8 respectively. When tightening, a torque wrench is used to tighten in stages according to the design torque, so that the pile cover seat 4, tower pile 1, and pipe pile 7 form a rigid connection whole.

[0024] Furthermore, the pile cap 4 is a square or circular structure (adapted to the cross-sectional shape of the tower pile 1). The gap between its inner contour and the outer contour of the upper end of the tower pile 1 is controlled at 10-20mm. During installation, the gap is filled with 1:2 cement mortar (with added waterproofing agent) so that the pile cap 4 completely covers the part of the tower pile 1 that protrudes from the ground, isolating external rainwater, soil particles and the concrete of the tower pile 1 from direct contact. The cross-sectional dimensions (side length or diameter) of the pile cap 4 are 200-300mm larger than the protruding end face of the tower pile 1. The specific dimensions need to cover the upper end of the pipe pile body 6 at the four corners (ensuring that the upper end of the pipe pile body 6 is completely located under the pile cap 4). The thickness of the pile cap 4 is designed to be 150-200mm (determined according to the bolt connection length and concrete bearing capacity), which ensures its own structural strength and provides sufficient stress space for the bolt connection.

[0025] The working principle is as follows: First, in the early stage of the construction of the transmission tower pile foundation, the tower pile 1 is pre-embedded to the preset depth underground as the core support component of the entire foundation; at the same time, several tower foot bolts 2 and internal bolts 3 are pre-embedded in the concrete at the upper end of the tower pile 1. The tower foot bolts 2 are used for subsequent connection with the transmission tower body, and the internal bolts 3 provide a connection foundation for the installation of the pile cover seat 4.

[0026] Next, at the corresponding underground positions around the tower pile 1, the pipe pile body 6 is pre-embedded and fixed to make it an auxiliary support component; then concrete is poured into the pipe pile body 6, and after the concrete solidifies, the pipe pile 7 is formed. During the forming process of the pipe pile 7, external bolts 8 are pre-embedded in the pipe pile 7 to make the external bolts 8 and the pipe pile 7 form a stable whole, providing a peripheral support connection point for the pile cover seat 4.

[0027] Then, the prefabricated pile cap 4 is hoisted to the designated position so that the part of the tower pile 1 protruding from the ground is exactly in the inner space of the pile cap 4. At the same time, the internal bolts 3 are passed through the countersunk holes on the pile cap 4, and the external bolts 8 are passed through the corner holes 9 at the four corners of the pile cap 4, so as to ensure that the pile cap 4 can be connected and aligned with the tower pile 1 and the pipe pile 7 at the same time.

[0028] Then, nuts 5 are fitted onto the exposed ends of the internal bolts 3 and external bolts 8 and tightened. Through the threaded engagement of nuts 5 and bolts, the pile cap 4 is firmly fixed between the upper end of the tower pile 1 and the upper end of the pipe pile 7, thereby forming a rigid connection between the pile cap 4, the tower pile 1, and the pipe pile 7, preventing relative displacement between the components.

[0029] Finally, after the pile cap 4 is connected and fixed, it completely covers the part of the tower pile 1 that protrudes above the ground, isolating it from direct contact with external rainwater, soil particles and other corrosive media, thus protecting the concrete structure at the top of the tower pile 1 from damage. On the other hand, when the transmission tower body is connected to the foundation through the tower foot bolts 2, the vertical and horizontal loads (such as strong wind loads) transmitted by the tower body will first act on the pile cap 4, and then the pile cap 4 will distribute the load to the central tower pile 1 and the surrounding pipe piles 7. Through the synergistic effect of "central support + surrounding auxiliary support", the bearing capacity and resistance to lateral displacement and settlement of the entire foundation structure are improved, ensuring the long-term stable operation of the transmission tower.

[0030] Any technical solution that achieves the above-mentioned technical effects by utilizing the technical solution described in this utility model, or by designing a similar technical solution inspired by the technical solution described in this utility model, falls within the protection scope of this utility model.

Claims

1. A reinforcement structure for the pile foundation of a transmission tower, characterized in that, The system includes a tower pile (1), tower foot bolts (2), internal bolts (3), pile cover seat (4), nuts (5), pipe pile body (6), pipe pile (7), external bolts (8), and corner holes (9). Several tower foot bolts (2) and internal bolts (3) are pre-embedded on the top of the tower pile (1). The internal bolts (3) are fixedly connected to the pile cover seat (4) through the nuts (5). External bolts (8) are embedded in the pipe pile body (6) around the tower pile (1). The external bolts (8) pass through the corner holes (9) of the pile cover seat (4) and are fixedly connected to the pile cover seat (4) through the nuts (5).

2. The reinforcement structure for a transmission tower pile foundation as described in claim 1, characterized in that: The tower foot bolt (2), the built-in bolt (3) and the external bolt (8) are all anchor bolts, wherein the height of the tower foot bolt (2) is higher than the height of the built-in bolt (3), and the built-in bolt (3) is located around the tower foot bolt (2).

3. The reinforcement structure for a transmission tower pile foundation as described in claim 2, characterized in that: The pile cap seat (4) has countersunk holes that match the built-in bolts (3), and the corner holes (9) at the four corners of the pile cap seat (4) are also countersunk holes.

4. The reinforcement structure for a transmission tower pile foundation as described in claim 3, characterized in that: The pile cap base (4) is provided with a pipe pile body (6) at the four corners. The pipe pile body (6) is embedded in the ground and protrudes outward at the top. The pipe pile body (6) is filled with concrete to form the pipe pile (7).

5. The reinforcement structure for a transmission tower pile foundation as described in claim 4, characterized in that: Each of the pipe pile bodies (6) has an external bolt (8) pre-embedded on the pipe pile (7) formed inside, corresponding to the corner hole (9). The pile cover seat (4) is fixedly connected to the internal bolt (3) and the external bolt (8) by a nut (5).

6. The reinforcement structure for a transmission tower pile foundation as described in claim 5, characterized in that: The pile cap (4) encloses the part of the upper end of the tower pile (1) that protrudes from the ground. The size of the pile cap (4) is larger than the size of the protruding end face of the tower pile (1).

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