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CN-121992773-A - Construction method of anchor pile structure and anchor pile structure formed by same

CN121992773ACN 121992773 ACN121992773 ACN 121992773ACN-121992773-A

Abstract

A construction method of an anchor pile structure suitable for a foundation with loose sand at least a shallow subsurface portion, the anchor pile structure comprising a hollow precast pile body (12), an anchor body structure (29) having a container (6) and a anchor rod (26), the method comprising the steps of 1) arranging the precast pile body (12) in a prescribed position in the foundation, 2) forming a hole (28) downward through the inside of the cavity of the pile body (12), the hole constituting an installation space of the anchor body structure (29) and being filled with slurry at this time, 3) passing the anchor body structure downward through the cavity of the precast pile body (12) and being placed in the inside of the hole, 4) pouring cement slurry into the hole (28) to displace the slurry in the hole, 5) filling the hollow inside of the container (6) with a medium after the cement slurry in the hole is hardened, performing squeeze-expansion to laterally expand the container (6), 6) grouting soil near the bottom end of the anchor rod (26).

Inventors

  • HU YUYIN
  • PANG ZUOHUI
  • SHI DUANXUE

Assignees

  • 上海同人里岩土工程技术有限公司

Dates

Publication Date
20260508
Application Date
20260330

Claims (20)

  1. 1. A method of constructing an anchor pile structure suitable for use on a foundation having loose sand at least in a shallow subsurface portion, the anchor pile structure comprising a hollow precast pile body (12), an anchor body structure (29) having a sealed flexible hollow vessel (6) and anchor rods (26), the method of constructing the anchor pile structure comprising the steps of: 1) In the foundation, the hollow precast pile body (12) is arranged at a prescribed position in the foundation in a descending manner; 2) Taking the precast pile body (12) as a retaining wall, penetrating through the cavity inside the hollow precast pile body (12), and downwards forming a hole (28) below the precast pile body (12), wherein the hole (28) forms an installation space of the anchor body structure (29), and the hole (28) is filled with slurry; 3) The anchor body structure (29) is downwards penetrated through the cavity of the precast pile body (12) and is placed in the hole (28); 4) Pouring cement slurry into the hole (28) to replace the slurry in the hole (28); 5) After the cement paste in the hole (28) is hardened, filling the hollow interior of the sealed flexible hollow container (6) with a medium, and performing squeeze-expansion to laterally expand the sealed flexible hollow container (6); 6) Grouting is carried out on the soil near the bottom end of the anchor rod (26) in a mode of reinforcing the soil with sediment at the bottom end of the anchor rod (26) and the soil at the anchor rod and the pile side.
  2. 2. The method of constructing an anchor pile structure according to claim 1, wherein the grouting in the step 6) is pressure grouting cement.
  3. 3. The method of constructing an anchor pile structure according to claim 1 or 2, wherein in the step 1), the hollow precast pile body (12) is installed at a predetermined position in the foundation in a descending manner by means of static pressure, hammering, and vibrating pile sinking.
  4. 4. A method of constructing an anchor pile structure according to any one of claims 1 to 3, wherein in the step 5), grouting is performed in the vessel (6) by means of a squeeze-and-expand grouting pipe (11) communicating with the inside of the sealed flexible hollow vessel (6) and a squeeze-and-expand grouting machine (16) communicating with the squeeze-and-expand grouting pipe (11) located inside the sealed flexible hollow vessel (6), and cement paste in the vessel (6) is hardened to form a cement paste stone body.
  5. 5. The method according to any one of claims 1 to 4, wherein in the step 6), soil near the bottom end of the anchor rod (26) is grouted by an anchor rod bottom grouting pipe (1) passing through the sealed flexible hollow container (6) and an anchor rod bottom grouting device (8) located near the bottom of the anchor rod (26) and communicated with the anchor rod bottom grouting pipe (1), thereby reinforcing the soil.
  6. 6. The method for constructing an anchor pile structure according to any one of claims 1 to 5, wherein the medium in the step 5) is cement slurry.
  7. 7. An anchor pile structure constructed by the construction method according to any one of claims 1 to 6, the anchor pile structure comprising an anchor body structure (29) and a hollow precast pile body (12), the anchor body structure (29) and the hollow precast pile body (12) being independent of each other, the anchor body structure (29) being located at a center lower position of the whole of the anchor pile structure, i.e., at a center lower position of the hollow precast pile body (12), and the hollow precast pile body (12) being located at an upper position of the whole of the anchor pile structure, an upper portion of the anchor body structure (29) being located in a lower cavity of the precast pile body (12) to realize a common load bearing; the upper part of the anchor structure (29) is located in the hollow position of the anchor pile structure, i.e. in the hollow part of the hollow precast pile body (12), and the hollow precast pile body (12) is located at the side part of the anchor pile structure, i.e. the hollow precast pile body (12) is arranged around the anchor structure (29), seen in the transverse direction, the anchor structure (29) comprises a transversely expandable sealed flexible hollow container (6), a sealing connection (4) is connected at the top port of the container (6) in a sealing manner to the top port, a bearing connection (18) is connected at the bottom port of the container (6) in a sealing manner to the bottom port, the anchor body structure (29) further comprises an anchor rod (26), the anchor rod (26) vertically passes through the sealing connecting piece (4) from top to bottom, the sealed flexible hollow container (6) is connected with the bearing connecting piece (18), a medium (7) is filled in the hollow part of the sealed flexible hollow container (6), an anchor rod bottom grouting device (8) for injecting a curing material below the bearing connecting piece (18) is connected to the bearing connecting piece (18), and one end of the anchor rod bottom grouting device (8) is communicated with the anchor rod bottom grouting pipe (1) above the anchor rod bottom grouting device.
  8. 8. Anchor pile structure according to claim 7, characterized in that the load bearing connection (18) is a load bearing plate.
  9. 9. Anchor pile structure according to claim 7 or 8, characterized in that the sealing connection (4) is a sealing connection plate.
  10. 10. An anchor pile structure according to any one of claims 7-9, characterized in that the grouting pipe (1) is connected to one end of the grouting device (8) from above and below through the sealing connection (4) and the sealed flexible hollow container (6).
  11. 11. Anchor pile structure according to any one of claims 7-10, characterized in that a grouting pipe connection sleeve (3) is arranged on the sealing connection piece (4), the grouting pipe (1) passes through the grouting pipe upper connection sleeve (3) from top to bottom, and the sealing connection piece (4) and the sealed flexible hollow container (6) are communicated with one end of the grouting machine (8).
  12. 12. Anchor pile structure according to any one of claims 7-11, characterized in that an anchor bottom grouting pipe upper connection sleeve (3) is arranged on the sealing connection piece (4), the anchor bottom grouting pipe (1) passes through the anchor bottom grouting pipe upper connection sleeve (3) from top to bottom, the sealing connection piece (4) and the sealed flexible hollow container (6), and an anchor bottom grouting pipe lower connection sleeve (30) arranged on the bearing connection piece (18) is communicated with one end of the anchor bottom grouting machine (8).
  13. 13. Anchor pile structure according to any one of claims 7-12, characterized in that the shank (26) comprises finish rolled rebars (10) and an insulated support steel tube (15) inside the sealed flexible hollow vessel (6) surrounding the finish rolled rebars (10).
  14. 14. Anchor pile structure according to any one of claims 7-12, characterized in that the anchor rods (26) comprise steel reinforcement (10) and an insulating support steel tube (15) inside the sealed flexible hollow container (6) surrounding the steel reinforcement (10).
  15. 15. Anchor pile structure according to any one of claims 7-12, characterized in that the anchor rods (26) comprise steel strands (10) and an insulating support steel tube (15) inside the sealed flexible hollow container (6) surrounding the steel strands (10).
  16. 16. Anchor pile structure according to any one of claims 7-13, characterized in that an upper limit nut (13) is arranged above, i.e. outside, the sealing connection piece (4), the anchor rod (26) comprises a finish rolled screw bar (10), the finish rolled screw bar (10) being fixed in position on the sealing connection piece (4) by means of the upper limit nut (13).
  17. 17. Anchor pile structure according to any one of claims 7-13, 16, characterized in that a lower limit nut (19) is arranged below, i.e. outside, the load bearing connection piece (18), the anchor shank (26) comprising finish rolled rebars (10), the finish rolled rebars (10) being fixed by positioning on the load bearing connection piece (18) by means of the lower limit nut (19).
  18. 18. Anchor pile structure according to any one of claims 7-13, 16,17, characterized in that an upper annular pressure plate (5) is arranged on the underside of the sealing connection (4), i.e. on the container side, for fixing and sealing the container (6) with the sealing connection (4).
  19. 19. Anchor pile structure according to any one of claims 7-13, 16-18, characterized in that a lower annular pressure plate (17) is arranged on the upper side of the load-bearing connection piece (18), i.e. on the container side, for fixing and sealing the container (6) with the load-bearing connection piece (18).
  20. 20. Anchor pile structure according to any one of claims 7-13, 16-19, characterized in that a squeeze-expansion grouting pipe connection sleeve (27) is provided on the sealing connection piece (4), the squeeze-expansion grouting pipe (11) passing through the squeeze-expansion grouting pipe connection sleeve (27) from top to bottom to communicate with one end of the squeeze-expansion grouting machine (16) located inside the sealed flexible hollow container (6).

Description

Construction method of anchor pile structure and anchor pile structure formed by same Technical Field The invention relates to the technology of the foundation field, in particular to a construction method of an anchor pile structure for a sandy land or a sandy soil foundation and the anchor pile structure formed by the method. Background The technical scheme adopted is that the precast pile is constructed step by step and split structure scheme is adopted, namely, the precast pile is firstly driven, then the precast pile is relied on for hole guiding, sand hole collapse is avoided, slurry replacement is carried out after an anchor body is installed, finally, squeezing, expanding and grouting and anchor bottom grouting are carried out, and a split anchor pile structure is formed. The applicant discloses in publication No. CN118048899A, published in year 5 and month 17 of 2024, a grouting expansion anchor pile structure and a construction method thereof, which essentially relates to a grouting expansion anchor pile structure which is assembled into a whole in advance and a pile sinking method for hole guiding implantation or stirring implantation. The in-depth research shows that the anchor pile structure and the construction method have four defects when applied to sandy soil sites: 1. The scheme disclosed in CN118048899a adopts a pile-planting method, namely, a drilling machine is firstly used for hole-planting, then a precast pile is planted in a drilled hole, but holes collapse easily to be generated at least in a foundation (or a sandy soil field) with loose sand on the shallow surface layer of the foundation, so that the precast pile (and an anchor body structure) is hard to sink in place, and the bearing capacity can not meet the design requirement, and the scheme adopts a stirring pile machine for stirring the dense sand at the pile position into cement, and then the precast pile is planted in the cement-soil stirring pile, but the sand is dense when meeting water, the precast pile becomes more dense soon after construction is completed, the subsequent integral precast pile and the anchor body structure are difficult to plant, the design elevation is difficult to reach, and the bearing capacity is difficult to meet the design requirement. 2. In the anchor pile disclosed in the above CN118048899a, the precast pile and the anchor structure are assembled in advance, and the anchor structure is easily damaged when the integrated structure is carried, moved and lowered into the hole during the construction process. 3. In the anchor pile disclosed in CN118048899a, the grouting is performed only in the grouting bag of the anchor body structure, the grouting is not performed at the end of the anchor rod, the sediment at the bottom of the anchor rod is not reinforced, and the compression bearing capacity of the anchor body structure-pile structure is not high. 4. In the anchor pile disclosed in CN118048899a, only the stirring implantation or the hole-guiding implantation mode can be used for construction, and the static pressure/hammering/vibration process cannot be used for construction, otherwise, the anchor body structure is easy to be damaged by load, and the application range is greatly limited. In summary, the construction process and the anchor pile structure disclosed in CN118048899a involve contradictions between the characteristics of simultaneous tensile and compression resistance, and the convenience of construction (workability) of the sandy foundation and the damage resistance of the anchor pile structure at the time of construction. Disclosure of Invention In view of the above-described problems in the prior art, i.e., in view of the above-described contradiction between the construction process involving the anchor pile and the anchor pile structure disclosed in CN118048899a, it is an object of the present invention to provide a construction method for an anchor pile structure suitable for a foundation with loose sand at least a shallow subsurface portion, and an anchor pile structure formed by the method, which can satisfy the requirements of the bearing capacity (i.e., the performance of simultaneously resisting tension and compression) of the anchor pile structure, i.e., the advantages of the technical scheme of retaining the anchor pile of CN118048899a, and which can be applied to the condition of a foundation (i.e., a sandy soil site) with easy hole where at least a shallow subsurface portion is loose sand, i.e., the construction under the condition is good, and the construction is convenient and reliable, while maintaining the anchor pile structure in the construction process. That is, the present invention aims to solve the contradiction between the construction process related to the anchor pile and the anchor pile structure disclosed in CN118048899a, and the present invention can achieve the compromise of the good construction performance of the sandy soil field, the satisfactory bear