Multi-section pressure-bearing type expansion anti-floating anchor rod structure and construction method thereof

Abstract

The multi-section pressure-bearing type expansion anti-floating anchor rod structure comprises a foundation raft plate (2), an annular anchoring seat (4) is fixedly installed on a raft plate embedded part (3), and the multi-section pressure-bearing type expansion anti-floating anchor rod structure is characterized in that a cylinder body (5) is vertically arranged in a drill hole in the bottom of the anchoring seat (4); an anti-floating expansion structure (6) is arranged at the bottom of the cylinder body (5), or one or more anti-floating expansion structures (6) are arranged in the middle of the cylinder body (5) at intervals, an anti-floating anchor rod (10) is inserted into an inner cavity of the cylinder body (5), and an expanded cone frustum (11) is arranged at the bottom of the anti-floating anchor rod (10) and corresponds to the anti-floating expansion structure (6) located in the middle of the cylinder body (5). And collapse or caving of a soil layer around a pile hole is avoided when the long anchor rod is installed, the installation depth and the installation precision of the anchor rod are guaranteed, and the drawing resistance and the floating resistance are remarkably improved.

Description

Technical Field

[0001] The invention relates to an anti-floating anchor rod structure and a construction method thereof, in particular to a multi-section pressure-bearing expanded anti-floating anchor rod structure and a construction method thereof, belonging to the technical field of underground foundation engineering. Background Art

[0002] With the continuous development of urbanization and the continuous advancement of construction technology, the construction of underground space is becoming more and more common, and the anti-floating problem of the foundation of buildings at a certain depth underground is prominent. For underground structures with large construction areas and deep foundations, the groundwater buoyancy that buildings need to bear is very huge. When the number of building floors is relatively small, when the groundwater level is high and the weight of the building structure is not enough to resist the buoyancy of the groundwater, the basement floor will be damaged and cracked under the action of groundwater. In severe cases, the concrete columns of the basement may even be destroyed. In the prior art, anti-floating anchor rods are set to offset part of the buoyancy of groundwater, and the anti-floating pull rods are fixed in the underground soil layer to transfer the load to the soil layer to achieve the anti-floating of the building structure. The existing anti-floating anchor rods have a simple structure and poor pull-out resistance. For underground structures with large construction areas and deep foundations, the basement floor often still has insufficient anti-floating force, resulting in damage and cracking of the basement floor, affecting the safety of the building structure, especially in the rainy season in the south, the situation is more serious. For a long time, there has been a lack of an anti-floating anchor structure that is easy to install and construct, has strong pull-out resistance, and can effectively prevent the basement from being destroyed under the huge pressure of groundwater to solve this technical problem. Summary of the invention

[0003] The purpose of the present invention is to provide a multi-section pressure-bearing expanded anti-floating anchor structure with a reasonable structure and prestressed tension expansion embedded anti-floating anchor structure, which can be reliably embedded in the soil layer around the pile hole and form an integral structure with the surrounding rock and soil layers, and the pull-out resistance and anti-floating performance are significantly improved, fundamentally avoiding the damage and cracking of the basement floor due to insufficient anti-buoyancy, thereby improving the safety of the building structure.

[0004] The second purpose of the present invention is to provide a construction method using a multi-section pressure-bearing expanded anti-floating anchor structure, which is convenient for installation and construction, avoids the collapse or collapse of the soil layer around the pile hole when installing long anchor rods, ensures the installation depth and installation accuracy of the anchor rod, and significantly improves the pull-out resistance and anti-floating performance.

[0005] To achieve the above-mentioned first invention purpose, the technical solution of the present invention is: a multi-section pressure-bearing expanded anti-floating anchor structure, including a foundation raft, a raft embedded part is pre-embedded and fixed in the foundation raft, an annular anchor seat is installed and fixed on the raft embedded part, and the bottom soil of the anchor seat is provided with a borehole for installing the anti-floating anchor structure, characterized in that: a cylinder is vertically arranged in the bottom borehole of the anchor seat, an anti-floating expansion structure is arranged at the bottom of the cylinder, or one or more anti-floating expansion structures are arranged at intervals in the middle of the cylinder, an anti-floating anchor is inserted into the inner cavity of the cylinder, an expanded head cone is arranged at the bottom of the anti-floating anchor and corresponding to the anti-floating expansion structure located in the middle of the cylinder, the large diameter end of the expanded head cone is located at the lower end, and the small diameter end of the expanded head cone is located at the upper end, the upper end of the anti-floating anchor is higher than the upper surface of the anchor seat, and the upper end of the anti-floating anchor is the anchor tensioning end.

[0006] Furthermore, a plurality of annularly distributed side wall deformation windows are provided on the middle side wall of the cylinder, and deformation bifurcated pieces are provided at the upper ends of the side wall deformation windows, with the bifurcated parts of the deformation bifurcated pieces facing the bottom end of the cylinder.

[0007] Furthermore, the anti-floating expansion structure is composed of a plurality of strip expansion structures distributed along the axial direction of the cylinder, and the strip expansion structures are distributed in a ring shape, and separation seams distributed along the axial direction of the cylinder are provided between adjacent strip expansion structures.

[0008] Furthermore, the anti-floating and expansion structure and the cylinder are an integrated structure, and the connection portion between the anti-floating and expansion structure and the cylinder is easily deformed and has good toughness.

[0009] Furthermore, the anti-floating and expansion structure is connected to the cylinder through a connecting structure, and the thickness of the anti-floating and expansion structure is not less than the wall thickness of the cylinder.

[0010] Furthermore, an annular fixing groove is provided at the lower end of the outer surface of the anti-floating and expansion structure, and a temporary restraining ring is installed in the annular fixing groove.

[0011] Furthermore, an annular fixing groove is provided on the bottom end surface of the anti-floating and expansion structure, and a temporary restraining ring is installed in the annular fixing groove.

[0012] Furthermore, the diameter of the small diameter end of the expanded truncated cone is smaller than the inner diameter of the cylinder, and the diameter of the large diameter end of the expanded truncated cone is larger than the inner diameters of the cylinder and the anti-floating expansion structure.

[0013] To achieve the above second invention objective, the technical solution of the present invention is: a construction method using a multi-section pressure-bearing expanded anti-floating anchor structure, characterized by comprising the following steps: a. First, drill a certain depth of pile holes in the soil at the bottom of the foundation raft for installing the anti-floating anchor structure to ensure the verticality of the pile holes; b. Then, a fixed anchor seat is installed on the foundation raft at the upper end of the pile hole so that the center hole on the anchor seat is approximately located on the axis of the pile hole; c. Assemble the anti-floating anchor rod inside the cylinder, check and ensure that the anti-floating expansion structure and the deformed bifurcated piece are in a closed state, and press the upper end of the cylinder against the bottom of the anchor seat or fix the upper end of the cylinder to the anchor seat; d. Then, the cylinder and the anti-floating anchor rod are integrally inserted and pressed into the pile hole, so that the cylinder and the anti-floating anchor rod reach a predetermined depth, and the tensioning end of the anchor rod at the upper end of the anti-floating anchor rod is higher than the upper surface of the center hole of the anchor seat; e. Then connect the tensioning end of the anchor rod with the tensioning end of the tensioning device, start the tensioning device to slowly tension the anti-floating anchor rod at the upper end of the anchor seat, keep the cylinder still during the tensioning process, and the expansion cone squeezes and opens the anti-floating expansion structure during the tensioning process; f. After tensioning to a certain degree, keep it for a while, and inject cement slurry into the cylinder after the anti-floating anchor rod 10 is stressed and stable. After solidification, remove the tensioning device to complete the installation operation.

[0014] The beneficial effects of the present invention are: 1. The present invention adopts a sleeve-type prestressed tensioned expansion embedded fixed expansion anti-floating anchor structure. The cylinder can not only serve as a force-bearing component, but also protect the soil of the pile hole during the installation process, avoiding the collapse or collapse of the soil layer around the pile hole when installing a long anchor rod, ensuring the installation depth and installation accuracy of the anchor rod, and can be tightened under the action of prestress, ultimately playing a good anti-floating role.

[0015] 2. The present invention is provided with an anti-floating expansion structure on the cylinder, and a corresponding expanded cone is provided on the anti-floating anchor rod. When subjected to radial outward expansion force, the strip-shaped expansion structure will produce plastic deformation and bend outward, embedding into the soil around the pile hole and forming a whole with it, thereby greatly enhancing the static friction between the anchor rod structure and the soil.

[0016] 3. According to the depth of the anchor rod and the abundance of groundwater, the present invention can add deformable bifurcated parts on the outer circumference of multiple parts of the cylinder. The deformable bifurcated parts can be expanded outward and embedded in the surrounding soil, which can further increase the contact area and embedding force between the cylinder and the surrounding soil.

[0017] 4. The present invention is easy to install. After the cylinder and the anti-floating expansion structure are installed, prestressing is performed. After the anti-floating anchor rod is stabilized by force, cement slurry is injected into the cylinder. This not only ensures the integrity of the anchor rod structure, but also solidifies the rock and soil layer near the pile hole, making it a larger integral structure with better stability and anti-floating performance. It fundamentally avoids damage and cracking of the basement floor due to insufficient anti-buoyancy, thereby improving the safety of the building structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention.

[0019] Figure 2 It is a usage state diagram of the present invention.

[0020] Figure 3 It is a structural schematic diagram of a first embodiment of the cylinder of the present invention.

[0021] Figure 4 It is a structural schematic diagram of a second embodiment of the cylinder of the present invention.

[0022] Figure 5 It is a structural schematic diagram of a third embodiment of the cylinder of the present invention.

[0023] Figure 6 It is a structural schematic diagram of the first embodiment of the anti-floating anchor rod of the present invention.

[0024] Figure 7 It is a schematic structural diagram of a second embodiment of the anti-floating anchor rod of the present invention.

[0025] Figure 8 It is a structural schematic diagram of the annular fixing groove of the present invention.

[0026] In the figure: soil 1, foundation raft 2, raft embedded parts 3, anchor seat 4, cylinder 5, anti-floating expansion structure 6, bifurcated opening 7, side wall deformation window 8, deformed bifurcated part 9, anti-floating anchor rod 10, expanded head frustum 11, annular fixing groove 12, temporary restraining ring 13, anchor rod tensioning end 14, grouting connection port 15. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0028] See also Figures 1 to 8A multi-stage pressure-bearing expanded anti-floating anchor structure of the present invention comprises a foundation raft 2, a raft embedded part 3 is pre-embedded and fixed in the foundation raft 2, an annular anchor seat 4 is installed and fixed on the raft embedded part 3, and a bottom soil body 1 of the anchor seat 4 is provided with a borehole for installing the anti-floating anchor structure, characterized in that: a cylinder 5 is vertically arranged in the bottom borehole of the anchor seat 4, an anti-floating expansion structure 6 is arranged at the bottom of the cylinder 5, or one or more anti-floating expansion structures 6 are arranged at intervals in the middle of the cylinder 5, an anti-floating anchor 10 is inserted into the inner cavity of the cylinder 5, an expanded head frustum 11 is arranged at the bottom of the anti-floating anchor 10 and corresponding to the anti-floating expansion structure 6 located in the middle of the cylinder 5, the large diameter end of the expanded head frustum 11 is located at the lower end, and the small diameter end of the expanded head frustum 11 is located at the upper end, the upper end of the anti-floating anchor 10 is higher than the upper surface of the anchor seat 4, and the upper end of the anti-floating anchor 10 is the anchor tensioning end 14.

[0029] A plurality of annularly distributed side wall deformation windows 8 are arranged on the middle side wall of the cylinder 5 , and deformation bifurcated pieces 9 are respectively arranged at the upper ends of the side wall deformation windows 8 , with the bifurcated parts of the deformation bifurcated pieces 9 facing the bottom end of the cylinder 5 .

[0030] The anti-floating expansion structure 6 is composed of a plurality of strip expansion structures distributed along the axial direction of the cylinder 5 , and the strip expansion structures are distributed in a ring shape, and separation seams distributed along the axial direction of the cylinder 5 are provided between adjacent strip expansion structures.

[0031] The anti-floating and expansion structure 6 and the cylinder 5 are an integrated structure, and the connection portion between the anti-floating and expansion structure 6 and the cylinder 5 is easily deformable and has good toughness.

[0032] The anti-floating and expansion structure 6 is connected to the cylinder 5 via a connecting structure, and the thickness of the anti-floating and expansion structure 6 is not less than the wall thickness of the cylinder 5 .

[0033] An annular fixing groove 12 is provided at the lower end of the outer surface of the anti-floating and expansion structure 6 , and a temporary restraining ring 13 is installed in the annular fixing groove 12 .

[0034] An annular fixing groove 12 is formed on the bottom end surface of the anti-floating and expansion structure 6 , and a temporary restraining ring 13 is installed in the annular fixing groove 12 .

[0035] The diameter of the small diameter end of the expanded cone 11 is smaller than the inner diameter of the cylinder 5 , and the diameter of the large diameter end of the expanded cone 11 is larger than the inner diameters of the cylinder 5 and the anti-floating expansion structure 6 .

[0036] A construction method using a multi-stage pressure-bearing expanded anti-floating anchor structure, characterized by comprising the following steps: a. First, a certain depth of pile holes for installing anti-floating anchor structures are drilled in the soil 1 at the bottom of the foundation raft 2 to ensure the verticality of the pile holes; b. Then, a fixed anchor seat 4 is installed on the foundation raft 2 at the upper end of the pile hole so that the center hole on the anchor seat 4 is approximately located on the axis line of the pile hole; c. Assemble the anti-floating anchor rod 10 inside the cylinder 5, check and ensure that the anti-floating expansion structure 6 and the deformable bifurcated member 9 are in a closed state, and place the upper end of the cylinder 5 against the bottom of the anchor seat 4 or fix the upper end of the cylinder 5 to the anchor seat 4; d. Then, the cylinder 5 and the anti-floating anchor rod 10 are integrally inserted and pressed into the pile hole, so that the cylinder 5 and the anti-floating anchor rod 10 reach a predetermined depth, and the anchor rod tensioning end 14 at the upper end of the anti-floating anchor rod 10 is higher than the upper surface of the center hole of the anchor seat 4; e. Then connect the anchor tensioning end 14 with the tensioning end of the tensioning device, start the tensioning device to slowly tension the anti-floating anchor 10 at the upper end of the anchor seat 4, keep the cylinder 5 still during the tensioning process, and the expanded cone 11 squeezes and opens the anti-floating expansion structure 6 during the tensioning process; f. After the tension is finally stretched to a certain extent, it is maintained for a period of time. After the anti-floating anchor rod 10 is stressed and stabilized, cement slurry is injected into the cylinder 5. After solidification, the tensioning device is removed to complete the installation operation.

[0037] See also Figure 1 , Figure 2 The anti-floating anchor structure of the present invention is arranged in the soil 1 at the bottom of the foundation raft 2, and the anti-floating anchor structure is evenly distributed in a certain area and reaches a certain number. The foundation raft 2 is pre-embedded and fixed with a raft embedded part 3 near the location where the anti-floating anchor structure is installed, and a ring-shaped anchor seat 4 is installed and fixed on the raft embedded part 3. A center hole is opened in the middle of the anchor seat 4. The anchor seat 4 is used to limit or fix the cylinder 5, and the anchor seat 4 is also used to connect and fix the tensioning device.

[0038] A cylinder 5 is vertically arranged in the bottom drill hole of the anchor seat 4. The cylinder 5 is made of a high-strength seamless stainless steel pipe, or a steel cage as a frame, and an anti-floating expansion structure 6 is fixedly installed on the steel cage frame. The bottom of the cylinder 5 is provided with an anti-floating expansion structure 6, and according to the actual engineering pull-out resistance requirements, one or more anti-floating expansion structures 6 can be added in the middle of the cylinder 5. The anti-floating expansion structure 6 is composed of a plurality of strip expansion structures distributed along the axial direction of the cylinder 5, and the strip expansion structures are distributed in an annular shape. Separation seams distributed along the axial direction of the cylinder 5 are arranged between adjacent strip expansion structures. When the strip expansion structure is subjected to radial outward expansion force, the root and nearby parts of the strip expansion structure will produce plastic deformation and bend outward, thereby increasing the oblique upward static friction with the soil 1.

[0039] The inner cavity of the cylinder 5 is provided with an anti-floating anchor rod 10 inserted therein. The anti-floating anchor rod 10 has high strength and good tensile strength. The outer diameter of the anti-floating anchor rod 10 is smaller than the inner diameter of the cylinder 5. The bottom of the anti-floating anchor rod 10 and the anti-floating expansion structure 6 located in the middle of the cylinder 5 are provided with an expanded head frustum 11. The large diameter end of the expanded head frustum 11 is located at the lower end, and the small diameter end of the expanded head frustum 11 is located at the upper end. The large diameter of the expanded head frustum 11 is larger than the inner diameter of the cylinder 5. The anti-floating anchor rod 10 will not be pulled out of the cylinder 5 when subjected to prestress and later stress. The expanded head frustum 11 is a solid frustum structure fixedly arranged on the anti-floating anchor rod 10. The outer surface of the frustum is smooth. When the anti-floating anchor rod 10 is prestressed and pulled, the outer conical surface of the expanded head frustum 11 squeezes each strip expansion structure on the anti-floating expansion structure 6, so that each strip expansion structure opens outward and fits with the surrounding soil 1.

[0040] In addition, in order to increase the contact area and the fitting force between the cylinder 5 and the surrounding soil, the present invention provides a plurality of annularly distributed side wall deformation windows 8 on the middle side wall of the cylinder 5, and the upper ends of the side wall deformation windows 8 are respectively provided with deformation bifurcated pieces 9, and the bifurcated parts of the deformation bifurcated pieces 9 face the bottom end of the cylinder 5. The purpose is to cause the deformation bifurcated pieces 9 to undergo plastic deformation when the inside of the cylinder 5 is squeezed or under the action of the anti-floating anchor rod 10 and the expanded head frustum 11, so that the deformation bifurcated pieces 9 are stretched outward, and the deformation bifurcated pieces 9 are embedded in the surrounding soil to form an integral structure with the surrounding soil, thereby improving the anti-pullout effect.

[0041] In addition, in order to avoid the anti-floating and expansion structure 6 from accidentally opening during the transportation process and the process of inserting and fixing the cylinder 5 into the pile hole, in order to solve this technical problem, the present invention provides an annular fixing groove 12 at the lower end of the outer surface of the anti-floating and expansion structure 6, and a temporary restraining ring 13 is installed in the annular fixing groove 12. An annular fixing groove 12 can also be provided on the bottom end face of the anti-floating and expansion structure 6, and a temporary restraining ring 13 is installed in the annular fixing groove 12. The temporary restraining ring 13 is a restraining ring made of hard plastic, which has limited strength and is easily broken under the action of external force, thus playing a role of temporary restraint. When the anti-floating and expansion structure 6 is squeezed by the expanded cone 11, when the squeezing force is greater than the tensile strength of the temporary restraining ring 13, the temporary restraining ring 13 will break quickly, and the anti-floating and expansion structure 6 will open quickly.

[0042] The construction method of the multi-stage pressure-bearing expansion anti-floating anchor structure adopted by the present invention is as follows: first, a pile hole of a certain depth for installing the anti-floating anchor structure is drilled in the soil 1 at the bottom of the foundation raft 2 to ensure the verticality of the pile hole. Then, the anchor seat 4 is fixedly installed on the foundation raft 2 at the upper end of the pile hole, so that the center hole on the anchor seat 4 is approximately located on the axis line of the pile hole. The anti-floating anchor 10 is assembled inside the cylinder 5, and it is checked and ensured that the anti-floating expansion structure 6 and the deformed bifurcated member 9 are in a closed state, and the upper end of the cylinder 5 is pressed against the bottom of the anchor seat 4 or the upper end of the cylinder 5 is fixed to the anchor seat 4. Then, the cylinder 5 and the anti-floating anchor 10 are integrally inserted and pressed into the pile hole, so that the cylinder 5 and the anti-floating anchor 10 reach a predetermined depth, and the anchor tensioning end 14 at the upper end of the anti-floating anchor 10 is higher than the upper surface of the center hole of the anchor seat 4. Then connect the anchor tensioning end 14 with the tensioning end of the tensioning device, start the tensioning device to slowly tension the anti-floating anchor 10 at the upper end of the anchor seat 4, keep the cylinder 5 immobile during the tensioning process, and the expanded cone 11 squeezes and opens the anti-floating expansion structure 6 during the tensioning process. Finally, after tensioning to a certain degree, keep it for a period of time, and after the anti-floating anchor 10 is stabilized by force, inject cement slurry or concrete mortar into the cylinder 5, and remove the tensioning device after solidification to complete the installation operation.

[0043] The above content is a further detailed description of the present invention in combination with specific implementation methods. It cannot be considered that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, the present invention will also have various simple substitutions, improvements and changes without departing from the concept of the present invention. Various simple substitutions, improvements and changes made should be deemed to belong to the scope of protection of the present invention.

Claims

1. A multi-stage pressure-bearing expanded anti-floating anchor structure, comprising a foundation raft (2), a raft embedded part (3) embedded and fixed in the foundation raft (2), an annular anchor seat (4) installed and fixed on the raft embedded part (3), a bottom soil (1) of the anchor seat (4) being provided with a drill hole for installing the anti-floating anchor structure, characterized in that: A cylinder (5) is vertically arranged in the bottom borehole of the anchor seat (4), an anti-floating expansion structure (6) is arranged at the bottom of the cylinder (5), or one or more anti-floating expansion structures (6) are arranged at intervals in the middle of the cylinder (5), an anti-floating anchor rod (10) is inserted into the inner cavity of the cylinder (5), and an expanded head frustum (11) is arranged at the bottom of the anti-floating anchor rod (10) and corresponding to the anti-floating expansion structure (6) located in the middle of the cylinder (5), the large diameter end of the expanded head frustum (11) is located at the lower end, and the small diameter end of the expanded head frustum (11) is located at the upper end, the upper end of the anti-floating anchor rod (10) is higher than the upper surface of the anchor seat (4), and the upper end of the anti-floating anchor rod (10) is the anchor rod tensioning end (14).

2. A multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: A plurality of side wall deformation windows (8) distributed in an annular shape are provided on the middle side wall of the cylinder (5), and deformation bifurcated pieces (9) are respectively provided at the upper ends of the side wall deformation windows (8), with the bifurcated portions of the deformation bifurcated pieces (9) facing the bottom end of the cylinder (5).

3. The multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: The anti-floating expansion structure (6) comprises a plurality of strip-shaped expansion structures distributed along the axial direction of the cylinder (5), and the strip-shaped expansion structures are distributed in a ring shape, and separation seams distributed along the axial direction of the cylinder (5) are provided between adjacent strip-shaped expansion structures.

4. The multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: The anti-floating and expansion structure (6) and the cylinder (5) are an integrated structure, and the connection portion between the anti-floating and expansion structure (6) and the cylinder (5) is easily deformable and has good toughness.

5. The multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: The anti-floating and expansion structure (6) is connected to the cylinder (5) via a connecting structure, and the thickness of the anti-floating and expansion structure (6) is not less than the wall thickness of the cylinder (5).

6. The multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: An annular fixing groove (12) is provided at the lower end of the outer surface of the anti-floating and expansion structure (6), and a temporary restraining ring (13) is installed in the annular fixing groove (12).

7. The multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: An annular fixing groove (12) is provided on the bottom end surface of the anti-floating and expansion structure (6), and a temporary restraining ring (13) is installed in the annular fixing groove (12).

8. The multi-section pressure-bearing expanded anti-floating anchor structure according to claim 1, characterized in that: The diameter of the small diameter end of the expanded truncated cone (11) is smaller than the inner diameter of the cylinder (5), and the diameter of the large diameter end of the expanded truncated cone (11) is larger than the inner diameters of the cylinder (5) and the anti-floating expansion structure (6).

9. A construction method using a multi-stage pressure-bearing expanded anti-floating anchor structure, characterized in that The following steps are involved: a. First, a pile hole of a certain depth for installing an anti-floating anchor structure is drilled in the soil (1) at the bottom of the foundation raft (2), and the verticality of the pile hole is ensured; b. Then, a fixed anchor seat (4) is installed on the foundation raft (2) at the upper end of the pile hole, so that the center hole on the anchor seat (4) is approximately located on the axis of the pile hole; c. Assemble the anti-floating anchor rod (10) inside the cylinder (5), check and ensure that the anti-floating expansion structure (6) and the deformable bifurcated member (9) are in a closed state, and place the upper end of the cylinder (5) against the bottom of the anchor seat (4) or fix the upper end of the cylinder (5) to the anchor seat (4); d. Then, the cylinder (5) and the anti-floating anchor rod (10) are integrally inserted and pressed into the pile hole, so that the cylinder (5) and the anti-floating anchor rod (10) reach a predetermined depth, and the anchor rod tensioning end (14) at the upper end of the anti-floating anchor rod (10) is higher than the upper surface of the center hole of the anchor seat (4); e. Then, the tensioning end (14) of the anchor rod is connected to the tensioning end of the tensioning device, and the tensioning device is started to slowly tension the anti-floating anchor rod (10) at the upper end of the anchor seat (4). During the tensioning process, the cylinder (5) is kept stationary, and during the tensioning process, the expanded cone (11) squeezes and opens the anti-floating expansion structure (6); f. After tensioning to a certain degree, the tensioning device is maintained for a period of time. After the anti-floating anchor rod (10) is stabilized by force, cement slurry is injected into the cylinder (5). After solidification, the tensioning device is removed to complete the installation operation.

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