Tower foundation structure for preventing and controlling freeze-thaw deformation in seasonal frozen soil region and construction method

Abstract

The invention discloses a tower foundation structure for preventing and controlling freeze-thaw deformation in a seasonal frozen soil area and a construction method. In the tower foundation structure, the lower portion of a pile body is connected with the top of a center cylinder through a hydraulic damper, the outer side of the bottom of the center cylinder is sleeved with an isolation cylinder, a conical cylinder is fixedly connected to the top of the isolation cylinder, and the conical cylinder is slidably connected to the outer side of the top of the center cylinder; the periphery of the central cylinder is fixedly connected with an upper inclined strut which is inclined upwards and a lower inclined strut which is inclined downwards; the end parts of the upper inclined strut and the lower inclined strut are movably inserted into through holes in the side wall of the isolation cylinder respectively; the bottom of the isolation cylinder is fixedly connected with a base, a lock pin is fixed to the upper portion of the base, the bottom of the center cylinder is hollow to form a center cylinder cavity allowing the lock pin to be inserted, the lock pin is slidably connected with the bottom of the center cylinder through the center cylinder cavity, a gap is reserved between the bottom of the center cylinder and the base, the hydraulic damper forms first-level prevention and control, and the upper inclined strut and the lower inclined strut form second-level prevention and control. The conical barrels form three-stage prevention and control, and the three stages of prevention and control work together to achieve whole-process control over frost heaving and thaw collapse deformation.

Description

Technical Field

[0001] The present invention relates to the technical field of prevention and control of freeze-thaw deformation of transmission and transformation facilities foundations, and particularly to a tower foundation structure and construction method for preventing and controlling freeze-thaw deformation in seasonal frozen soil areas. Background Technique

[0002] Seasonal frozen soil areas in China are widely distributed in the northeastern, northern, northwestern regions and the edge of the Qinghai-Tibet Plateau. Their typical characteristics are that the soil freezes and swells in winter and melts and subsides in summer, with significant annual freeze-thaw cycles. In recent years, the construction scale of transmission and transformation projects in seasonal frozen soil areas has been continuously expanding. However, the frequent freeze-thaw action in this area causes the soil around the tower foundation to repeatedly freeze and heave and thaw and subside, leading to foundation uplift, inclination and even fracture, seriously threatening the safe operation of the power grid.

[0003] Traditional tower foundations mostly adopt shallow-buried designs. Although they have the advantages of convenient construction and low cost, they are directly exposed to the active freeze-thaw layer and are easily affected by the frost heaving force generated by soil phase change. The current prevention and control technologies mainly focus on two categories: one is to inhibit deformation by enhancing the frost resistance of foundation materials (such as high-strength concrete, fiber composite materials), but the material cost is high and the action of the frost heaving force cannot be eliminated; the other is to adopt deep foundations or thermal insulation and water isolation measures (such as polystyrene board insulation layer, gravel replacement), which can partially relieve the frost damage, but greatly increase the construction complexity and cost, and are insufficiently adaptable in areas with strong frost heaving. The current technical bottleneck lies in the excessive pursuit of the "zero deformation" rigid resistance mode of the foundation, ignoring the optimization of the soil-foundation interaction mechanism during the freeze-thaw process. The traditional structure lacks a dissipation design for the repeated stress caused by freeze-thaw cycles and is prone to cause foundation fatigue damage. Therefore, there is an urgent need for a new type of foundation structure that takes into account economy and reliability, and realizes the active prevention and control of freeze-thaw deformation by reconstructing the frost heaving force distribution and improving the collaborative deformation ability of the foundation and frozen soil.

[0004] Based on the concept of "combining dredging and control", the present invention breaks through the rigid frost resistance thinking and proposes a tower foundation integrating a load-sharing structure, comprehensively solving the freeze-thaw deformation problem from three dimensions: optimizing the frost heaving force transmission path, releasing deformation energy and automatic locking, and providing an innovative solution for the long-term and stable operation of power infrastructure in seasonal frozen soil areas. Summary of the Invention

[0005] The purpose of the present invention is to provide a tower foundation structure for preventing and controlling freeze-thaw deformation in seasonal frozen soil areas in view of the technical defects existing in the prior art. Through the synergistic action of a hydraulic damping mechanism and a deformation locking mechanism, the freeze-thaw force on the foundation is effectively reduced, the freeze-thaw deformation of the foundation is alleviated, and at the same time, the horizontal frost heaving force is better utilized to offset the action of the tangential frost heaving force.

[0006] Another purpose of the present invention is to provide a construction method for the tower foundation structure.

[0007] The technical solution adopted to achieve the purpose of the present invention is as follows: A tower foundation structure for preventing and controlling freeze-thaw deformation in seasonally frozen soil areas, comprising a pile body, a hydraulic damper, a conical cylinder, an isolation cylinder and a central cylinder, wherein: The lower part of the pile body is connected to the top of the central cylinder through a hydraulic damper. An isolation cylinder is sleeved outside the bottom of the central cylinder. The conical cylinder is fixedly connected to the top of the isolation cylinder, and the conical cylinder is slidably connected to the outside of the top of the central cylinder; The upper inclined struts inclined upward and the lower inclined struts inclined downward are fixedly connected around the central cylinder. The ends of the upper inclined struts and the lower inclined struts are respectively inserted into the through holes on the side wall of the isolation cylinder. The upper inclined struts and the lower inclined struts are made of elastic materials; The bottom of the isolation cylinder is fixedly connected to a base, and a locking pin is fixed on the upper part of the base. The bottom of the central cylinder is hollow to form a central cylinder cavity for the locking pin to insert. The locking pin is slidably connected to the bottom of the central cylinder through the central cylinder cavity, and there is a gap between the bottom of the central cylinder and the base; The isolation cylinder is completely located below the seasonally frozen soil layer. The pile body, the conical cylinder and the hydraulic damper are completely located within the seasonally frozen soil layer. The top of the pile body is flush with the natural ground surface, and the bottom of the conical cylinder is flush with the maximum seasonal frost depth.

[0008] On the other hand, the present invention also includes a working method of the tower foundation structure, comprising the following steps: When the seasonally frozen soil freezes and expands, the tangential frost heaving force generated acts on the pile body first, driving it to generate an upward displacement. The hydraulic damper acts first, and the hydraulic damper provides a resistance force in the opposite direction to the frost heaving force to offset the influence of the frost heaving force. When the hydraulic damper reaches the locked state, the pile body drives the central cylinder to move upward, and the upper inclined strut starts to act. The upper inclined strut gradually extends out of the through hole of the isolation cylinder and pierces into the surrounding soil to form an "inverted barb" anchoring effect; at the same time, the lower inclined strut retracts into the isolation cylinder accordingly; when entering the thaw settlement stage in the warm season, the melting of the soil causes the pile body to be subjected to a downward pulling force, making the hydraulic damper return to its initial position. As the settlement further develops, the central cylinder starts to move downward driven by the pile body. At this time, the lower inclined strut extends out of the through hole and pierces into the surrounding soil to inhibit the settlement of the structure by increasing the side wall friction resistance. When the bottom of the central cylinder contacts the base, the base will provide the final bearing capacity support.

[0009] In the above technical solution, the upper inclined struts and the lower inclined struts are made of elastic metal.

[0010] In the above technical solution, the inclined angle of the conical cylinder slope is not less than 26.57°.

[0011] In the above technical solution, the upper diagonal braces and the lower diagonal braces are alternately fixed in layers outside the central tube. Each layer of upper diagonal braces is composed of N upwardly inclined upper support pieces at the same height, and each layer of lower diagonal braces is composed of N downwardly inclined lower support pieces at the same height.

[0012] In the above technical solution, N is 3 to 6.

[0013] In the above technical solution, the N upper support pieces at the same height are evenly distributed in a umbrella shape outside the central tube, and the N lower support pieces at the same height are evenly distributed in a umbrella shape outside the central tube.

[0014] In the above technical solution, the hydraulic damper includes a piston body fixed to the bottom of the pile body, a hydraulic chamber formed at the top of the central tube, and a plurality of damping channels formed on the side wall at the top of the central tube. The piston body is slidably connected in the hydraulic chamber. The hydraulic chamber is divided into an upper hydraulic chamber and a lower hydraulic chamber. The upper hydraulic chamber and the lower hydraulic chamber are filled with an anti-freezing medium. A sealing ring is fixed on the outer wall of the piston body. Both ends of each damping channel are communicated with the hydraulic chamber, and the openings at one end of the plurality of damping channels are arranged from high to low.

[0015] In the above technical solution, the center lines of the plurality of damping channels are located on the same straight line.

[0016] In the above technical solution, each damping channel is an arc structure.

[0017] In the above technical solution, the cross-sectional area of the upper hydraulic chamber minus the cross-sectional area of the piston body is equal to the cross-sectional area of the lower hydraulic chamber.

[0018] On the other hand, the present invention further includes a construction method of the tower foundation structure, comprising the following steps: S1, construction preparation: conduct frozen soil geological exploration, understand the characteristics of seasonal frozen soil in the site, and formulate a construction plan based on this; S2, foundation positioning: use surveying instruments to conduct site layout, determine the center position and elevation control points of the foundation, and mark the installation positions of each structural component; S3, structure fabrication and assembly: prefabricate the main components in the factory, assemble the hydraulic damper on site and test the sealing performance, weld and fix the upper diagonal braces and the lower diagonal braces to the central tube, complete the overall pre-assembly and check the matching dimensions of each component; S4, drilling: use a rotary drilling rig to construct the pile hole. The drilling diameter needs to be larger than the designed diameter of the isolation tube. During the drilling process, strictly control the verticality deviation, promptly handle the collapse of the hole wall, remove the sediment at the bottom of the hole after the hole is formed, and ensure the bottom of the hole is flat; S5, Structural hoisting: Use special lifting tools for integral hoisting, strictly control the positioning accuracy, and install temporary supports in a timely manner after the structure is in place to ensure construction safety; S6, Void backfilling and compaction: Backfill improved soil in layers, and use small compaction equipment to compact layer by layer. Pause when backfilling to the bottom of the conical cylinder, and continue backfilling to the design elevation after inspecting the vertical condition of the structure; S7, Project acceptance: Conduct a comprehensive inspection of the structural installation quality, make complete construction acceptance records, and complete the anti-corrosion treatment.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. This system has multi-level prevention and control. First is the primary prevention and control composed of hydraulic dampers, then the secondary prevention and control composed of upper diagonal braces and lower diagonal braces, and then the tertiary prevention and control formed by the conical cylinder. By changing the action direction of the frost heaving force, the original destructive normal force is transformed into a beneficial binding force. The primary, secondary, and tertiary prevention and control work together to achieve the whole-process control of frost heaving and thaw settlement deformation; 2. The conical cylinder, base, and locking pin work together to only allow the central cylinder to move strictly vertically, completely avoiding the possibility of lateral inclination, and significantly improving the safety and reliability of the tower foundation under complex frozen soil conditions; 3. The progressive pressure increase process of the hydraulic damper realizes three key functions: First, significantly reduce the peak value of the frost heaving force through hydraulic reaction force; second, effectively dissipate the axial tensile stress of the pile foundation; finally, prevent the excessive uplift of the pile while allowing controllable displacement. This dynamic balance mechanism not only protects the structural integrity of the pile, but also significantly improves the stability performance of the foundation in the repeated freeze-thaw cycles of seasonal frozen soil. Description of the Drawings

[0020] Figure 1 The following shows the overall structural schematic diagram of the present invention.

[0021] Figure 2 It is the connection structural schematic diagram of the pile body, hydraulic damper, central cylinder, upper diagonal brace, and lower diagonal brace.

[0022] Figure 3 It is the structural schematic diagram of the conical cylinder, base, and locking pin.

[0023] Figure 4 It is the structural schematic diagram of the isolation cylinder.

[0024] Figure 5 It is the sectional view of the present invention.

[0025] Figure 6 It is the sectional view of the hydraulic damper.

[0026] Figure 7 It is the schematic diagram of the frost heaving force acting on the inclined surface of the conical cylinder.

[0027] Figure 8 This is the flow chart of the construction method of the present invention.

[0028] In the figure: 1, pile body; 2, hydraulic damper; 3, conical cylinder; 4, isolation cylinder; 5, base; 6, damping channel; 7, upper diagonal brace; 8, lower diagonal brace; 9, central cylinder; 10, central cylinder cavity; 11, locking pin; 12, isolation cavity; 13, upper hydraulic cavity; 14, lower hydraulic cavity; 15, piston body; 16, sealing ring; 17, through hole. Specific embodiments

[0029] The present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] Embodiment 1 As Figures 1-5 shown, a tower foundation structure for preventing and controlling freeze-thaw deformation in seasonally frozen soil areas includes a pile body 1, a hydraulic damper 2, a conical cylinder 3, an isolation cylinder 4, and a central cylinder 9, wherein: The lower part of the pile body 1 is connected to the top of the central cylinder 9 through a hydraulic damper 2. An isolation cylinder 4 is sleeved outside the bottom of the central cylinder 9. The conical cylinder 3 is fixedly connected to the top of the isolation cylinder 4, and the conical cylinder 3 is slidably connected to the outside of the top of the central cylinder 9; An inclined upward upper diagonal brace 7 and an inclined downward lower diagonal brace 8 are fixedly connected around the central cylinder 9. The ends of the upper diagonal brace 7 and the lower diagonal brace 8 are respectively movably inserted into through holes 17 on the side wall of the isolation cylinder 4; The bottom of the isolation cylinder 4 is fixedly connected to a base 5. A locking pin 11 is fixed on the upper part of the base 5. The bottom of the central cylinder 9 is hollow to form a central cylinder cavity 10 for the locking pin 11 to insert. The locking pin 11 is slidably connected to the bottom of the central cylinder 9 through the central cylinder cavity 10, and there is a gap between the bottom of the central cylinder 9 and the base 5; The isolation cylinder 4 is completely located below the seasonally frozen soil layer. The pile body 1, the conical cylinder 3, and the hydraulic damper 2 are completely located within the seasonally frozen soil layer. The top of the pile body 1 is flush with the natural ground surface, and the bottom of the conical cylinder 3 is flush with the maximum seasonal freezing depth.

[0031] When the seasonal frozen soil freezes and swells, the generated tangential frost heaving force acts on the pile body 1 preferentially, driving it to generate an upward displacement. The hydraulic damper 2 acts first, and the hydraulic damper 2 provides a resistance force in the opposite direction of the frost heaving force to offset the influence of the frost heaving force. When the hydraulic damper 2 reaches the locked state, the pile body 1 drives the central cylinder 9 to move upward, and the upper diagonal brace 7 begins to act. Specifically, the upper diagonal brace 7 gradually extends from the through hole 17 of the isolation cylinder 4 and pierces into the surrounding soil, forming an anchoring effect similar to a "barb". During the development of frost heaving, as the upper diagonal brace 7 gradually extends and anchors into the surrounding soil, the acting force it exerts on the isolation cylinder 4 increases synchronously; at the same time, the lower diagonal brace 8 retracts into the isolation cylinder 4 accordingly. The upper diagonal brace 7 and the lower diagonal brace 8 are made of elastic metal and always maintain an elastic deformation state throughout the movement process to ensure their reusable performance. When entering the thaw settlement stage in the warm season, the system exhibits an adaptive recovery characteristic: First, the soil thaws, and the pile body 1 is pulled downward and descends, causing the hydraulic damper 2 to return to its initial position; as the thaw settlement further develops, the central cylinder 9 begins to move downward driven by the pile body 1. At this time, the lower diagonal brace 8 extends from the through hole 17 and pierces into the surrounding soil to inhibit the structural settlement by increasing the side wall friction resistance. When the bottom of the central cylinder 9 contacts the base 5, the base 5 will provide the ultimate bearing capacity support. It is particularly noteworthy that the elastic restoring forces of the upper diagonal brace 7 and the lower diagonal brace 8 will act synergistically to push the central cylinder 9 accurately back to the initial design position, and this characteristic effectively ensures the dimensional stability and durability of the structure during multiple freeze-thaw cycles. During the entire working process, the upper diagonal brace 7, the lower diagonal brace 8 and the hydraulic damper form a perfect cooperation to achieve the full-process control of frost heaving and thaw settlement deformation.

[0032] The mechanical optimization design of the conical cylinder 3 realizes the self-locking effect of the frost heaving force. When the freezing front extends to the burial depth of the conical cylinder 3, its unique inclined surface structure plays a key role: by changing the acting direction of the frost heaving force, the original destructive normal force is converted into a beneficial binding force. Specifically, as Figure 7 shown, the frost heaving force is decomposed into a normal force ( F f ) and a tangential force ( F q ) on the inclined surface of the conical cylinder, and there is a clear mechanical relationship between their vertical components F fs 、 F qs . By accurately calculating the inclination angle of the inclined surface of the conical cylinder, it is ensured that the mechanical condition of F qs ≤ F fs always holds; ; In the formula: F fis the normal component of the frost heaving force on the inclined surface of the conical cylinder; F q is the tangential component of the frost heaving force on the inclined surface of the conical cylinder; θ is the angle between the inclined surface of the conical cylinder and the vertical direction. The inclination angle of the inclined surface of the conical cylinder 3 θ should not be less than 26.57°. This design ingeniously utilizes the frost heaving force itself to achieve automatic locking of the conical cylinder 3, effectively inhibiting the upward displacement of the isolation cylinder 4, providing a reliable bottom anchoring force for the pile body 1, and significantly improving the stability performance of the foundation during the frost heaving period.

[0033] The anti-overturning stability of the structure consists of a triple protection mechanism composed of the conical cylinder 3, the base 5, and the locking pin 11. The spatial constraint principle of the three components is as follows: The central cylinder 9 is precisely restricted to move within the internal space of the conical cylinder 3, and the top of the locking pin 11 penetrates into the cavity 10 of the central cylinder, and the bottom of the locking pin 11 is rigidly connected to the base 5. This nested structure design forms a three-dimensional constraint system, and its mechanical characteristics are as follows: First, the precise fit between the inner wall of the conical cylinder 3 and the outer wall of the central cylinder 9 restricts the horizontal displacement; second, the guiding function of the locking pin 11 within the cavity 10 of the central cylinder ensures the linearity of the vertical movement; finally, the fixed connection between the base 5 and the isolation cylinder 4 provides a stable foundation platform.

[0034] Preferably, the upper diagonal braces 7 and the lower diagonal braces 8 are alternately fixed in layers on the outside of the central cylinder 9. Each layer of the upper diagonal braces 7 is composed of N upwardly inclined upper support pieces at the same height, and each layer of the lower diagonal braces 8 is composed of N downwardly inclined lower support pieces at the same height. More preferably, N is 3 to 6. The N upper support pieces at the same height are evenly distributed in an umbrella shape on the outside of the central cylinder 9, and the N lower support pieces at the same height are evenly distributed in an umbrella shape on the outside of the central cylinder 9.

[0035] Embodiment 2 As Figure 6 shown, on the basis of Embodiment 1, the structure of the hydraulic damper 2 is further optimized in this embodiment.

[0036] The hydraulic damper 2 includes a piston body 15 fixed to the bottom of the pile body 1, a hydraulic cavity formed at the top of the central cylinder 9, and a plurality of damping channels 6 formed on the side wall at the top of the central cylinder 9. The piston body 15 is slidably connected to the hydraulic cavity. The hydraulic cavity includes an upper hydraulic cavity 13 and a lower hydraulic cavity 14. The upper hydraulic cavity 13 and the lower hydraulic cavity 14 are filled with an antifreeze medium. A sealing ring 16 is fixed on the outer wall of the piston body 15. Both ends of each damping channel 6 are communicated with the hydraulic cavity. The openings at one end of the plurality of damping channels 6 are arranged from high to low. Preferably, the center lines of the plurality of damping channels 6 are located on the same straight line.

[0037] The cross-sectional area of the upper hydraulic cavity 13 minus the cross-sectional area of the piston body 15 is equal to the cross-sectional area of the lower hydraulic cavity 14. When the piston body 15 moves, the volume changes of the upper hydraulic cavity 13 and the lower hydraulic cavity 14 are equal, ensuring the normal movement of the piston body 15.

[0038] When the tangential frost heaving force acts on the pile body 1, the pile body 1 drives the piston body 15 to slide upward in the hydraulic damper 2, compressing the anti-freezing medium in the upper hydraulic cavity 13. The anti-freezing medium in the upper hydraulic cavity 13 enters the damping channel 6 through one end opening of the damping channel 6 and flows out from the other end opening into the lower hydraulic cavity 14. In this embodiment, three damping channels 6 are provided. More preferably, each damping channel 6 is an arc structure. At the initial stage of frost extraction, the center line of the piston body 15 is located on the center line of the damping channel 6. One end opening of each damping channel 6 is located in the upper hydraulic cavity 13, and the other end opening is located in the lower hydraulic cavity 14. The anti-freezing medium flows through all three damping channels 6. As frost extraction further occurs, the piston body 15 rises, and the number of damping channels 6 with openings above the piston body 15 decreases, that is, the number of damping channels 6 for the anti-freezing medium to flow through decreases. First, it decreases to two damping channels 6 for the anti-freezing medium to flow through, and then decreases to one. During this process, the resistance gradually increases, and the pressure of the anti-freezing medium in the upper hydraulic cavity 13 acting on the piston body 15 gradually increases.

[0039] During the entire frost extraction process, by virtue of the incompressible property of the anti-freezing medium and the damping effect of the damping channel 6, a progressive pressure increase process is formed in the upper hydraulic cavity 13. This pressure reacts on the pile body 1 through the piston body 15, generating an anchoring force in the opposite direction to the frost heaving force, thereby effectively decomposing and offsetting the influence of the frost heaving force. During the continuous action of the frost heaving force, the system exhibits an intelligent response characteristic: as the pile body 1 slowly lifts, the sealing ring 16 synchronously displaces with the piston body 15 and gradually closes the damping channel 6 in a preset order. This progressive closing mechanism ensures that the system damping force increases with the displacement. When all the damping channels 6 are completely closed, the system reaches a force balance state, and the piston body 15 stops moving.

[0040] In the initial stage of frost heaving action, after all the damping channels 6 of the hydraulic damper 2 are completely closed and the piston body 15 reaches the locked state, with the continuous action of the frost heaving force, the pile body 1 will drive the central cylinder 9 to move upward as a whole.

[0041] Embodiment 3 As Figure 7 shown, the construction method of the tower foundation structure for preventing and controlling freeze-thaw deformation in the seasonal frozen soil area includes the following steps: S1, Construction Preparation: Before construction, a detailed geological survey of seasonal frozen soil is required to understand the characteristics of the seasonal frozen soil on the site. Based on the survey results, a special construction plan is formulated, necessary construction equipment and materials are prepared, and technical disclosure is provided to the construction personnel.

[0042] S2, Foundation Positioning: Use surveying instruments to conduct site layout, determine the center position of the foundation and the elevation control points. Mark the installation positions of each structural component to ensure accurate positioning.

[0043] S3, Structure Fabrication and Assembly: Prefabricate the main components in the factory and assemble them on-site. During the assembly process, first assemble the hydraulic damper 2, then weld the upper diagonal brace 7 and the lower diagonal brace 8 to the outside of the central tube 9. After assembling the isolation tube 4, weld the isolation tube 4 to the base 5, and finally weld the conical tube 3 to complete the overall pre-assembly and check the mating dimensions of each component.

[0044] S4, Drilling: Use a rotary drilling rig to construct the pile hole. The drilling diameter should be slightly larger than the designed diameter of the isolation tube. During the drilling process, strictly control the verticality deviation and promptly handle problems such as hole wall collapse. After the hole is formed, remove the sediment at the bottom of the hole to ensure the bottom of the hole is flat.

[0045] S5, Structure Hoisting: Use special lifting tools for overall hoisting and strictly control the hoisting accuracy. Install temporary supports in a timely manner after the structure is in place to ensure construction safety.

[0046] S6, Void Backfilling and Compaction: Backfill the improved soil in layers and compact it layer by layer using small compaction equipment. Pause when backfilling to the bottom of the conical tube, and continue backfilling to the designed elevation after inspecting the vertical condition of the structure.

[0047] S7, Project Acceptance: Conduct a comprehensive inspection of the structure installation quality, including geometric dimensions, mechanical properties, etc. Make complete construction acceptance records and complete the finishing work such as anti-corrosion treatment.

[0048] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A tower foundation structure for preventing and controlling freeze-thaw deformation in seasonally frozen ground areas, characterized in that, It includes a pile body, a hydraulic damper, a conical cylinder, a isolation cylinder and a central cylinder, where: The lower part of the pile body is connected to the top of the central cylinder through a hydraulic damper. An isolation cylinder is sleeved outside the bottom of the central cylinder. The conical cylinder is fixedly connected to the top of the isolation cylinder, and the conical cylinder is slidably connected to the outside of the top of the central cylinder; Inclined upward upper braces and inclined downward lower braces are fixedly connected around the central cylinder. The ends of the upper braces and the lower braces are respectively inserted into through holes on the side wall of the isolation cylinder. The upper braces and the lower braces are made of elastic materials; The bottom of the isolation cylinder is fixedly connected to a base. A locking pin is fixed on the upper part of the base. A central cylinder cavity for the locking pin to insert is formed in the hollow bottom of the central cylinder. The locking pin is slidably connected to the bottom of the central cylinder through the central cylinder cavity. There is a gap between the bottom of the central cylinder and the base; The isolation cylinder is completely located below the seasonal frozen soil layer. The pile body, the conical cylinder and the hydraulic damper are completely located in the seasonal frozen soil layer. The top of the pile body is flush with the natural ground surface, and the bottom of the conical cylinder is flush with the maximum seasonal freezing depth.

2. The tower foundation structure for preventing freeze-thaw deformation in seasonal frozen soil areas according to claim 1, wherein The upper braces and the lower braces are made of elastic metal.

3. The tower foundation structure for preventing and controlling freeze-thaw deformation in seasonal frozen soil areas according to claim 1, wherein, The inclined angle of the conical cylinder slope is not less than 26.57°.

4. The tower foundation structure for preventing freeze-thaw deformation in seasonally frozen ground areas according to claim 1, wherein, The upper braces and the lower braces are alternately fixed in layers outside the central cylinder. Each layer of upper braces is composed of N inclined upward upper support pieces at the same height. Each layer of lower braces is composed of N inclined downward lower support pieces at the same height.

5. The tower foundation structure for preventing freeze-thaw deformation in seasonal frozen soil areas according to claim 4, characterized in that, N is 3 to 6.

6. The tower foundation structure for preventing freeze-thaw deformation in seasonal frozen soil areas according to claim 4, characterized in that, The N upper support pieces at the same height are evenly distributed in a umbrella shape outside the central cylinder. The N lower support pieces at the same height are evenly distributed in a umbrella shape outside the central cylinder.

7. The tower foundation structure for preventing freeze-thaw deformation in seasonal frozen soil areas as claimed in claim 1, wherein, The hydraulic damper includes a piston body fixed to the bottom of the pile body, a hydraulic cavity formed at the top of the central cylinder, and a plurality of damping channels formed on the side wall of the top of the central cylinder. The piston body is slidably connected in the hydraulic cavity. The hydraulic cavity is divided into an upper hydraulic cavity and a lower hydraulic cavity. The upper hydraulic cavity and the lower hydraulic cavity are filled with anti-freezing media. A sealing ring is fixed on the outer wall of the piston body. Both ends of each damping channel are communicated with the hydraulic cavity. The openings of one ends of the plurality of damping channels are arranged from high to low.

8. The tower foundation structure for preventing freeze-thaw deformation in seasonal frozen soil areas as described in claim 1, wherein The center lines of the plurality of damping channels are on the same straight line. Each damping channel is an arc structure.

9. The tower foundation structure for preventing freeze-thaw deformation in seasonal frozen soil areas according to claim 1, characterized in that, The cross-sectional area of the upper hydraulic cavity minus the cross-sectional area of the piston body is equal to the cross-sectional area of the lower hydraulic cavity.

10. The construction method of the tower foundation structure according to any one of claims 1-9, characterized in that, It includes the following steps: S1, construction preparation: conduct frozen soil geological exploration, understand the characteristics of seasonal frozen soil in the site, and formulate a construction plan based on this; S2, foundation positioning: use surveying instruments to conduct site layout, determine the center position and elevation control points of the foundation, and mark the installation positions of each structural component; S3, structure manufacturing and assembly: prefabricate the main components in the factory, assemble the hydraulic damper on site and test the sealing performance, weld and fix the upper braces and the lower braces to the central cylinder, complete the overall pre-assembly and check the matching dimensions of each component; S4, Drilling: Use a rotary drilling rig to construct the pile hole. The drilling diameter should be larger than the designed diameter of the isolation cylinder. During the drilling process, strictly control the verticality deviation, promptly handle the collapse of the hole wall, and remove the sediment at the bottom of the hole after the hole is formed to ensure the bottom of the hole is flat; S5, Structure Hoisting: Use special lifting tools for integral hoisting, strictly control the positioning accuracy, and promptly install temporary supports after the structure is in place to ensure construction safety; S6, Void Backfilling and Compaction: Backfill the improved soil material in layers and compact it layer by layer using small compaction equipment. Pause when backfilling to the bottom of the conical cylinder, and continue backfilling to the designed elevation after inspecting the vertical condition of the structure; S7, Project Acceptance: Conduct a comprehensive inspection of the structure installation quality, make complete construction acceptance records, and complete the anti-corrosion treatment.

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