Freezing pulling prevention and control device for shallow-buried self-anchored pile foundation in frozen soil area and construction method

Abstract

The invention discloses a frozen soil area shallow-buried self-anchored pile foundation freezing and pulling prevention and control device and a construction method, the frozen soil area shallow-buried self-anchored pile foundation freezing and pulling prevention and control device comprises an anchoring cylinder, a sleeve, a pile foundation and a base, the pile foundation and the base are installed in the anchoring cylinder, the pile foundation is installed at the top of the base, and the anchoring cylinder is sleeved with the sleeve; through the arrangement of the upper block, the lower block, the upper open groove and the lower open groove of the anchoring barrel, the effect of changing the cross section in real time according to frost heaving development is provided for the anchoring barrel. Meanwhile, the stress condition of the pile foundation in the frost heaving period is optimized through the synergistic effect of the clamping blocks and the supports, when the upper block inclines inwards and deforms in the frost heaving period, the supports are extruded to contract towards the pile foundation, the gaps between the clamping blocks and the supports are gradually reduced till the clamping blocks make contact with the supports, the clamping blocks press the supports downwards, the supports apply downward force to the pile foundation, and the pile foundation is prevented from being pulled upwards. In addition, the stability and the anti-freezing and anti-pulling capacity of the pile foundation are enhanced through the base, and the shallow-buried pile foundation is promoted to meet the strict deformation control requirement.

Description

Technical Field

[0001] The present invention relates to the technical field of construction for preventing and controlling frost pullout of light and shallow pile foundations, and in particular to a device for preventing and controlling frost pullout of shallow-buried self-anchored pile foundations in frozen soil areas and a construction method. Background Art

[0002] The special climatic and geological conditions in permafrost areas pose severe challenges to pile foundation engineering. During the alternation of seasons, the freeze-up effect caused by repeated freezing and thawing of the soil will seriously affect the stability of the pile foundation, causing deformation of the superstructure at the least and engineering accidents at the worst. To address this problem, the engineering community generally adopts the method of increasing the buried depth of the pile foundation to resist the freeze-up force by exerting the anchoring effect of the deep soil. Although this traditional method is theoretically reliable, it has obvious limitations in practical applications: for projects with lighter loads and shallower buried depths, excessive buried depth requirements will not only greatly increase the amount of materials used, but will also significantly increase the difficulty of construction and the cost of the project, making it difficult to meet engineering needs in terms of economy and practicality.

[0003] At present, the frost pullout prevention and control technologies used in engineering practice mainly include physical isolation, soil improvement, drainage and anti-seepage, and structural reinforcement. Although these methods can work under certain conditions, they each have obvious shortcomings: some have complex construction processes and demanding operating conditions; some have unstable prevention and control effects and are difficult to adapt to complex frozen soil environments; and some projects are too expensive and do not have the value of large-scale promotion. Especially in light and shallow pile foundation projects with strict requirements for deformation control, the applicability of existing technologies is even more insufficient. Therefore, the development of a new type of pile foundation structure that can effectively prevent and control frost pullout deformation and has the advantages of simple construction and economic rationality has become a key technical problem that needs to be solved in the current construction of frozen soil areas.

[0004] In view of this, the present invention proposes a frost-uplift prevention and control device and construction method for shallow buried self-anchored pile foundations in frozen soil areas, which utilizes horizontal frost heave force and the radial compression deformation of the structure itself to form a self-anchored anti-freeze-uplift structure, providing an innovative solution for the prevention and control of shallow pile foundation diseases. Summary of the invention

[0005] The purpose of the present invention is to provide a shallow buried self-anchored pile foundation frost-uplift prevention and control device in frozen soil areas to address the technical defects existing in the prior art. The device utilizes the extrusion of shallow horizontal frost heave force to achieve the function of vertical variable cross-section, thereby forming a wedge-shaped self-anchoring mechanism, effectively alleviating the problem of frost-uplift disease of shallow buried pile foundations.

[0006] Another object of the present invention is to provide a construction method for the above-mentioned shallow buried self-anchored pile foundation freeze-up prevention and control device in frozen soil areas.

[0007] The technical solution adopted to achieve the purpose of the present invention is: A freeze-thaw uplift prevention and control device for shallowly buried self-anchored pile foundations in frozen soil areas, comprising an anchoring cylinder, a sleeve, a pile foundation and a base. The pile foundation and the base are installed inside the anchoring cylinder, the pile foundation is installed on the top of the base, and the sleeve is sleeved on the anchoring cylinder. The anchoring cylinder includes a plurality of upper partitions located in the active layer of the frozen soil area, a plurality of lower partitions located in the frozen layer of the frozen soil area, as well as clamping blocks and connecting rings arranged between the upper partitions and the lower partitions. The upper partitions and the lower partitions are arranged in an up-and-down corresponding manner. The plurality of upper partitions enclose to form a cylindrical structure with a plurality of upper slots. Each of the upper slots is arranged between two adjacent upper partitions. A plurality of clamping blocks are arranged at different heights on the inner wall of each upper partition. The plurality of lower partitions enclose to form a cylindrical structure with a plurality of lower slots. Each of the lower slots is arranged between two adjacent lower partitions. A first clamping block is fixed on the outer edge of the bottom of each lower partition. A plurality of supports are evenly spaced along the axial direction of the pile foundation. One end of each support is fixed on the pile foundation. Each support extends obliquely upward, and the other end is located below a clamping block with a gap therebetween. A plurality of limiting protrusions are evenly fixed on the outer wall of the base along its circumferential direction. Each limiting protrusion corresponds to a lower slot and fits into the lower slot. A second clamping block is fixed on the outer edge of the bottom of each limiting protrusion. The second clamping blocks and the first clamping blocks are alternately arranged at intervals to enclose to form a protruding clamping ring.

[0008] In the above technical solution, a lower slot is correspondingly arranged below each upper slot, and the upper partitions and the lower partitions are elastic structures.

[0009] In the above technical solution, the upper slot opens upward, and the bottom wall of the slot is the upper top surface of the connecting ring. The lower slot opens downward, and the bottom wall of the slot is the lower bottom surface of the connecting ring.

[0010] In the above technical solution, the thickness of the limiting protrusion is the same as the thickness of the lower partition, so that the limiting protrusion fits into the lower slot. The limiting protrusions and the lower partitions are alternately arranged at intervals to enclose to form a cylindrical shape. The upper top surface of the limiting protrusion contacts the lower bottom surface of the connecting ring, and the upper top surface of the base is flush with the upper top surface of the connecting ring.

[0011] In the above technical solution, the sleeve is a steel wire reinforced rubber sleeve, and a Teflon coating is applied to the outer wall of the sleeve.

[0012] In the above technical solution, the length of the upper partition is greater than the length of the lower partition.

[0013] Another aspect of the present invention also includes a working method of the freeze-thaw uplift prevention and control device for shallowly buried self-anchored pile foundations in frozen soil areas, comprising the following steps: Step 1: When the shallow layer of the frozen soil area freezes, it triggers the development of frost heave in the surrounding soil, generating tangential frost heave force and horizontal frost heave force on the anti-frost heave and uplift prevention device of the self-anchored pile foundation. Under the action of the horizontal frost heave force, the sleeve undergoes elastic deformation until it squeezes the upper baffle to incline inward and drives the lower baffle to incline outward. With the connecting ring as the fulcrum, a "seesaw" effect is formed. At the same time, the first clamping block is squeezed and inserted into the surrounding soil mass. Step 2: The frost heave continues to develop, the upper baffle further inclines and deforms inward, the support contracts towards the pile foundation, the clamping block moves downward as the upper baffle inclines, and the gap between the clamping block and the support gradually decreases until they come into contact. The clamping block squeezes the support downward, and the pile foundation bears the downward pressure to prevent the pile foundation from being uplifted.

[0014] In the above technical solution, when the surrounding soil frost heaves and develops, the limit convex block is inserted into the frozen soil layer to limit the anchoring cylinder.

[0015] In the above technical solution, the second clamping block engages with the surrounding soil mass, and the base serves as the base structure of the pile foundation to prevent the pile foundation from being uplifted.

[0016] In the above technical solution, the lower bottom surface of the sleeve is flush with the lower bottom surface of the connecting ring, and the lower part of the sleeve is located in the frozen soil layer of the frozen soil area.

[0017] Another aspect of the present invention further includes a construction method for an anti-frost heave and uplift prevention device for a shallowly buried self-anchored pile foundation in a frozen soil area, comprising the following steps: Step 1: Construction preparation: Conduct on-site investigation to determine the depth of the active layer and geological conditions in the frozen soil area, mark the pile positions and clean the site. Step 2: Pile foundation positioning: Locate the central coordinates of the pile foundation, mark the excavation range and depth, and review the length of the anchoring cylinder according to the frozen soil depth to ensure that the lower end of the sleeve is embedded at least 0.5 m below the frozen soil layer in the frozen soil area. Step 3: Drilling: Vertically drill to the marked range and depth. The diameter of the drill hole is 10 - 15 cm larger than the outer diameter of the anchoring cylinder. After drilling, clean the residue at the bottom of the hole, check the integrity of the hole wall, and prevent the collapse of the hole from affecting the installation. Step 4: Lift and install the structure of the anti-frost heave and uplift prevention device for the self-anchored pile foundation except the sleeve until the clamping ring is in close contact with the bottom of the drill hole, and then lift and install the sleeve until its bottom surface is flush with the bottom surface of the connecting ring. Step 5: Backfill and compact: Layer by layer backfill weakly frost-heaving sand and gravel outside the sleeve in the drill hole to the top of the sleeve, with each layer thickness ≤ 30 cm, and compact it with a plate compactor. Replace and compact the original soil within a range of 0.5 m from the top of the sleeve to enable the backfill body to deform synergistically with the surrounding frozen soil. Step 6: Completion acceptance: Check the sealing performance of the sleeve, the moving gap between the support and the clamping block, and the fit between the limit convex block and the lower slot, conduct a static load test to verify the bearing capacity of the entire structure, measure the verticality deviation of the pile foundation, and retain the construction records and image data for filing.

[0018] In the above technical solution, a total station or GPS is used to locate the central coordinates of the pile foundation.

[0019] In the above technical solution, a spiral drill is used to drill a vertical hole.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The settings of the upper partition, lower partition, upper slot, and lower slot of the anchoring cylinder in the present invention provide the basis for the anchoring cylinder to have a variable cross-section in real time according to the frost heave development. At the same time, the synergistic effect of the clamping block and the support optimizes the stress conditions of the pile foundation during the frost heave period. When the upper partition inclines inward and deforms during the frost heave period, it squeezes the support to contract towards the pile foundation. The gap between the clamping block and the support gradually decreases until they come into contact. The clamping block presses down on the support, and the support applies a downward force to the pile foundation to prevent the pile foundation from being uplifted. Moreover, the base strengthens the stability and anti-frost heave uplift ability of the pile foundation, enabling the shallowly buried pile foundation to meet the strict deformation control requirements; 2. Backfilling the gap between the device of the present invention and the hole wall with weakly frost-heaving gravel further alleviates the frost heave and uplift deformation of the pile foundation. First of all, the backfill soil has weak frost heave characteristics, and its own frost heave can be ignored. It only generates deformation and displacement under the drive of the frost heave of the soil outside the hole wall, forming a deformation buffer layer between the natural soil and the structure, weakening the intensity of the frost heave development of the soil around the pile; on the other hand, the backfill soil is gravel, which belongs to coarse-grained fillings with relatively large particle sizes, significantly weakening the contact effect and friction force between the soil and the side wall of the structure. Therefore, backfilling with weakly frost-heaving gravel can directly reduce the frost heave uplift force; 3. The device of the present invention is simple to construct and causes less disturbance to the frozen soil and the environment. The device of the present invention has a vertical variable cross-section during the operation period. The entire device can be prefabricated and assembled in the factory for the main body. The construction process is the same as that of the pile foundation and can be completed through the processes of drilling - hoisting - backfilling. The area of frozen soil disturbance is small, enabling rapid construction and being environmentally friendly. It solves the problems that the construction of conventional variable cross-section frost heave prevention and control foundations requires excavation, formwork support, pouring, and long-term curing, and the construction process has a greater impact on the frozen soil temperature and environmental disturbance. Description of the Drawings

[0021] Figure 1 It is a schematic diagram of the overall structure of the frost heave prevention and control device of the present invention (partially installed in the soil).

[0022] Figure 2 It is an axonometric sectional view of the frost heave prevention and control device of the present invention.

[0023] Figure 3 It is a schematic diagram of the overall structure of the frost heave prevention and control device of the present invention (removing the sleeve).

[0024] Figure 4 It is a schematic diagram of the structure of the pile foundation and the base.

[0025] Figure 5 It is a schematic diagram of the structure of the anchoring cylinder.

[0026] Figure 6 It is an axonometric sectional view of the anchoring cylinder.

[0027] Figure 7 It is a partial enlarged view (support and chuck).

[0028] Figure 8 It is a schematic diagram of the deformation of the anchoring cylinder during the frost heaving period.

[0029] Figure 9 It is the construction flow chart of the present invention.

[0030] Wherein, 1: anchoring cylinder, 101: upper baffle, 102: lower baffle, 103: connecting ring, 2: sleeve; 3: pile foundation, 4: base, 5: upper slot, 6: lower slot, 7: chuck, 8: first clamping block, 9: support, 10: limiting lug, 11: second clamping block. Specific embodiments

[0031] The present invention will be further described in detail below with reference to 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.

[0032] Embodiment 1 As Figures 1-7 shown, a frost heaving prevention and control device for shallowly buried self-anchored pile foundations in frozen soil areas includes an anchoring cylinder 1, a sleeve 2, a pile foundation 3 and a base 4. The pile foundation 3 and the base 4 are installed in the anchoring cylinder 1, and the pile foundation 3 is fixedly installed on the top of the base 4. Specifically, the pile foundation 3 is vertically and fixedly installed at the center of the top of the base 4. The sleeve 2 is sleeved on the upper part of the anchoring cylinder 1, and the sleeve 2 is used to isolate the pile foundation 3 from the frozen soil and reduce the tangential frost heaving force.

[0033] The anchoring cylinder 1 includes a plurality of upper partitions 101 located in the active layer of the frozen soil area, a plurality of lower partitions 102 located in the frozen layer of the frozen soil area, and a connecting ring 103 arranged between the upper partitions 101 and the lower partitions 102. The upper partitions 101 and the lower partitions 102 are arranged corresponding to each other up and down. The plurality of upper partitions 101 are evenly spaced. The plurality of upper partitions 101 enclose a cylindrical structure with a plurality of upper slots 5. Each of the upper slots 5 is arranged between two adjacent upper partitions 101. A plurality of clamping blocks 7 are fixed on the inner wall of each upper partition 101. The plurality of clamping blocks 7 are located at different heights of the upper partition 101. The plurality of lower partitions 102 are evenly spaced. The plurality of lower partitions 102 enclose a cylindrical structure with a plurality of lower slots 6. Each of the lower slots 6 is arranged between two adjacent lower partitions 102. A first clamping block 8 is fixed on the outer edge of the bottom of each lower partition 102. The upper slots 5 and the lower slots 6 are arranged corresponding to each other up and down. The upper partitions 101 and the lower partitions 102 are of elastic structures. The elastic structures and the settings of the upper slots 5 and the lower slots 6 all increase the freedom degree of deformation of the anchoring cylinder 1 caused by frost heaving.

[0034] Further, the lower bottom surface of the sleeve 2 is flush with the lower bottom surface of the connecting ring 103, and the top surface of the sleeve 2 is flush with the top surface of the anchoring cylinder 1 (i.e., the top surface of the upper partition 101). The lower part of the sleeve 2 is located in the frozen layer of the frozen soil area, so as to prevent the soil from entering the anchoring cylinder 1 through the upper slots 5, and at the same time prevent the anchoring cylinder 1 from contacting the soil, thereby reducing the tangential frost heaving force.

[0035] Further, the bottom groove wall of the upper slot 5 is the upper top surface of the connecting ring 103, and the bottom groove wall of the lower slot 6 is the lower bottom surface of the connecting ring 103.

[0036] A plurality of circles of supports 9 are evenly spaced along the axial direction of the pile foundation 3. Each circle of supports 9 is evenly distributed along the circumferential direction of the pile foundation 3. One end of each support 9 is fixed on the pile foundation 3. Each support 9 extends obliquely upward until the other end is located below a clamping block 7 (it can be in contact with the inner wall of the upper partition 101 or there is a gap), and there is a gap between it and the clamping block 7. A plurality of limiting convex blocks 10 are evenly spaced along the circumferential direction on the outer wall of the base 4. Each limiting convex block 10 corresponds to a lower slot 6 and fits with the lower slot 6 for limiting the anchoring cylinder 1. A second clamping block 11 is fixed on the outer edge of the bottom of each limiting convex block 10. The second clamping block 11 has the same thickness as the first clamping block 8. The second clamping blocks 11 and the first clamping blocks 8 are alternately arranged at intervals to enclose a protruding clamping ring.

[0037] Further, the thickness of the limiting bump 10 is the same as that of the lower baffle 102. After the limiting bump 10 fits into the lower slot 6, a plurality of limiting bumps 10 and a plurality of lower baffles 102 are alternately arranged at intervals to enclose a cylindrical shape. The upper top surface of the limiting bump 10 contacts the lower bottom surface of the connecting ring 103 (i.e., the bottom wall of the lower slot 6), and the upper top surface of the base 4 is flush with the upper top surface of the connecting ring 103.

[0038] Further, the sleeve 2 is a steel wire reinforced rubber sleeve, and its outer wall is coated with a Teflon coating. The Teflon coating has strong hydrophobicity and non-stickiness. When the surrounding soil freezes, the water freezes and cannot bond with the sleeve 2. In addition, the surface of the Teflon coating is smooth and has an extremely low friction coefficient, further reducing the frictional force between the sleeve 2 and the soil. The superposition of the above mechanisms significantly weakens the uplift force of the tangential frost heaving force on the entire device.

[0039] Further, the length of the upper baffle 101 is greater than that of the lower baffle 102. Specifically, the length ratio of the upper baffle 101 to the lower baffle 102 is 2:1. After frost heaving deformation, the extrusion force of the first clamping block 8 on the surrounding soil is significantly enhanced.

[0040] Embodiment 2 As Figures 1-8 shown, on the basis of Embodiment 1, this embodiment provides a working method for a frost heaving prevention and control device for a shallowly buried self-anchored pile foundation in a frozen soil area, including the following steps.

[0041] Step 1, after installing the self-anchored pile foundation frost heaving prevention and control device in the frozen soil area, the second clamping block 11 and the first clamping block 8 bite with the soil to increase the biting force between the entire device and the soil.

[0042] Step 2, when the shallow layer of the frozen soil area freezes, it causes the surrounding soil to develop frost heaving, generating tangential frost heaving force and horizontal frost heaving force on the self-anchored pile foundation frost heaving prevention and control device. Under the action of the horizontal frost heaving force, the sleeve 2 undergoes elastic deformation until it squeezes the upper baffle 101 to tilt inward and drives the lower baffle 102 to tilt outward, forming a "seesaw" effect with the connecting ring 103 as the fulcrum. At the same time, the first clamping block 8 squeezes and inserts into the surrounding soil. This process forms two frost heaving prevention and control mechanisms: (1) the inclined deformation of the upper baffle 101 and the lower baffle 102 makes the anchoring cylinder 1 form a wedge-shaped structure, increasing the anti-uplift ability; (2) the first clamping block 8 squeezes and inserts into the surrounding soil, increasing the frictional resistance between the anchoring cylinder 1 and the soil. The superposition of the two frost heaving prevention and control mechanisms increases the anchoring effect of the anchoring cylinder 1 during the frost heaving period.

[0043] Step 3, frost heave continues to develop, the upper block 101 further tilts inward and deforms, the support 9 shrinks toward the pile foundation 3, the block 7 moves downward with the tilt of the upper block 101, the gap between the block 7 and the support 9 gradually decreases until the two are in contact, the block 7 squeezes the support 9 downward, the pile foundation 3 bears the downward pressure, and the pile foundation 3 is prevented from pulling up. In this frost heave process, the base 4 strengthens the stability and anti-freeze pulling ability of the pile foundation 3. First, the base 4 is fixedly connected to the pile foundation 3, and the support 9 is coordinated to limit the horizontal displacement of the pile foundation 3 to prevent the pile foundation 3 from tilting; second, the limiting protrusion 10 set around the base 4 can well limit the anchor cylinder 1 to prevent the anchor cylinder 1 from rotating and moving downward; third, the second blocking block 11 set at the bottom end of the base 4 can better increase the bite force with the soil body and enhance the ability of the whole device to resist freeze-thaw deformation; fourth, the base 4, as the base structure of the pile foundation 3, is located in the frozen soil layer below the active layer, avoiding the seasonal freeze-thaw effect, and can provide a stable bearing capacity for the pile foundation 3. In summary, the base 4 strengthens the stability and anti-freezing pullout capability of the pile foundation 3 , enabling the shallow buried pile foundation 3 to meet the stringent deformation control requirements.

[0044] Example 3 like Figures 8-9 As shown, based on Example 1, this embodiment provides a construction method for a shallow buried self-anchored pile foundation freeze-up prevention and control device in a frozen soil area, comprising the following steps.

[0045] Step 1: prefabricate the structure, weld and assemble all the components of the self-anchored pile foundation freeze-up prevention and control device described in Example 1 except the sleeve 2, and set them aside.

[0046] Step 2, construction preparation: conduct on-site survey to determine the depth of active layer and geological conditions in the permafrost area, mark the pile positions and clean the site.

[0047] Step 3, positioning of pile foundation 3: use a total station or GPS to locate the center coordinates of pile foundation 3, mark the excavation range and depth, and verify the length of anchor tube 1 according to the frozen soil depth to ensure that the lower end of sleeve 2 is embedded at least 0.5m below the frozen soil layer (stable frozen soil layer) in the frozen soil area.

[0048] Step 4, drilling: Use a spiral drill to drill vertically to the marked range and depth. The diameter of the hole should be 10-15 cm larger than the outer diameter of the anchor tube 1. Clean the residue at the bottom of the hole after drilling, check the integrity of the hole wall, and prevent the hole from collapsing and affecting the installation.

[0049] Step 5, hoist the structure assembled in step 1 until the retaining ring is in close contact with the bottom of the drill hole, and then hoist the sleeve 2 until the bottom surface is flush with the bottom surface of the connecting ring 103.

[0050] Step 6, backfill and compaction: Backfill the weak frost-susceptible gravel in layers outside the sleeve 2 in the borehole to the top of the sleeve 2, with each layer thickness ≤ 30 cm, and compact it with a plate compactor. Replace and compact the original soil within a range of 0.5 m from the top of the sleeve 2 to enable the backfill body to deform synergistically with the surrounding frozen soil.

[0051] Step 7, completion acceptance: Check the sealing performance of the sleeve 2, the movable gap between the support 9 and the clamping block 7, and the fit between the limit convex block 10 and the lower slot 6, conduct a static load test to verify the bearing capacity of the entire structure, measure the verticality deviation of the pile foundation 3 (≤ 1%), and retain the construction records and image data for archiving.

[0052] 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 device for preventing and controlling frost heaving of shallowly buried self-anchored pile foundations in frozen soil areas, characterized in that, It includes an anchoring cylinder, a sleeve, a pile foundation and a base. The pile foundation and the base are installed inside the anchoring cylinder. The pile foundation is installed on the top of the base, and the sleeve is sleeved on the anchoring cylinder. The anchoring cylinder includes a plurality of upper partitions located in the active layer of the frozen soil area, a plurality of lower partitions located in the frozen layer of the frozen soil area, clamping blocks arranged at different heights on the inner wall of the upper partitions, and a connecting ring arranged between the upper partitions and the lower partitions. The upper partitions and the lower partitions are arranged in an up-and-down corresponding manner. A plurality of upper partitions enclose to form a cylindrical structure with a plurality of upper slots. Each of the upper slots is arranged between two adjacent upper partitions. A plurality of lower partitions enclose to form a cylindrical structure with a plurality of lower slots. Each of the lower slots is arranged between two adjacent lower partitions. A first clamping block is fixed on the outer edge of the bottom of each lower partition. A plurality of supports are evenly spaced along the axial direction of the pile foundation. One end of each support is fixed on the pile foundation. Each support extends obliquely upward. The other end of each support is located below a clamping block. There is a gap between each support and the clamping block. A plurality of limiting protrusions are evenly fixed on the outer wall of the base along its circumferential direction. Each limiting protrusion corresponds to a lower slot and fits with the lower slot. A second clamping block is fixed on the outer edge of the bottom of each limiting protrusion. The second clamping blocks and the first clamping blocks are alternately arranged at intervals to enclose a protruding clamping ring.

2. The anti-freezing and pulling prevention device for shallow-buried self-anchored pile foundation in frozen soil area according to claim 1, wherein, A lower slot is correspondingly arranged below each upper slot. The upper partitions and the lower partitions are of elastic structures.

3. The anti - frost heaving prevention and control device for shallow - buried self - anchored pile foundation in frozen soil area according to claim 1, wherein, The upper slot opens upward, and the bottom wall of the upper slot is the upper top surface of the connecting ring. The lower slot opens downward, and the bottom wall of the lower slot is the lower bottom surface of the connecting ring.

4. The anti - frost - heaving and control device for shallow - buried self - anchored pile foundation in frozen soil area according to claim 1, characterized in that, The thickness of the limiting protrusion is the same as the thickness of the lower partition, so that the limiting protrusion fits into the lower slot. The limiting protrusions and the lower partitions are alternately arranged at intervals to enclose a cylindrical shape.

5. The anti-freezing and pulling prevention device for shallowly buried self-anchored pile foundation in frozen soil area according to claim 1, characterized in that, The upper top surface of the limiting protrusion contacts the lower bottom surface of the connecting ring. The upper top surface of the base is flush with the upper top surface of the connecting ring.

6. The anti - frost heaving and prevention device for shallow - buried self - anchored pile foundation in frozen soil area according to claim 1, characterized in that, The sleeve is a steel wire reinforced rubber tube sleeve, and a Teflon coating is applied to the outer wall of the sleeve.

7. The anti-freezing and pulling prevention device for shallow-buried self-anchored pile foundation in frozen soil area according to claim 1, characterized in that, The length of the upper partition is greater than the length of the lower partition.

8. The construction method of the anti-freezing and pulling prevention device for shallowly buried self-anchored pile foundation in frozen soil area according to any one of claims 1 to 7, characterized in that, It includes the following steps: Step 1, construction preparation: conduct on-site investigation to determine the depth of the active layer of the frozen soil area and the geological conditions, mark the pile positions and clean the site. Step 2, pile foundation positioning: position the central coordinates of the pile foundation, mark the excavation range and depth, and recheck the length of the anchoring cylinder according to the frozen soil depth to ensure that the lower end of the sleeve is embedded at least 0.5 m below the frozen layer of the frozen soil area. Step 3, drilling: vertically drill to the marked range and depth. The diameter of the drill hole is 10 - 15 cm larger than the outer diameter of the anchoring cylinder. After drilling, clean the residue at the bottom of the hole, check the integrity of the hole wall, and prevent the collapse of the hole from affecting the installation. Step 4, hoist the structure of the self-anchoring pile foundation frost heave prevention and control device except the sleeve until the clamping ring is in close contact with the bottom of the drill hole, and then hoist the sleeve until its bottom surface is flush with the bottom surface of the connecting ring. Step 5, backfill and compaction: layer by layer backfill weakly frost-susceptible gravel outside the sleeve in the drill hole to the top of the sleeve, with each layer thickness ≤ 30 cm, and compact it with a plate compactor. At 0.5 m away from the top of the sleeve, replace and compact the original soil to enable the backfill body to deform synergistically with the surrounding frozen soil. Step 6, completion acceptance: Check the sealing performance of the sleeve, the moving gap between the support and the chuck, and the fit between the limit lug and the lower slot, conduct a static load test to verify the bearing capacity of the entire device, measure the verticality deviation of the pile foundation, and retain the construction records and image data for filing.

9. The construction method according to claim 8, characterized in that, Use a total station or GPS to locate the central coordinates of the pile foundation.

10. The construction method according to claim 8, characterized in that, Use a spiral drill to drill vertically.

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