Fabricated anchor rod foundation structure of 1 + X type power transmission line and construction method

Abstract

The invention relates to the technical field of overhead power transmission line engineering, and discloses a 1 + X type power transmission line fabricated anchor rod foundation structure and a construction method.The 1 + X type power transmission line fabricated anchor rod foundation structure comprises a prefabricated anchor rod, a groove type prefabricated bearing platform and a U-shaped prefabricated bearing platform are connected to the prefabricated anchor rod, and a connecting steel plate is connected to the upper end of the prefabricated anchor rod through double nuts; a grouting part is arranged between the groove type prefabricated bearing platform and the U-shaped prefabricated bearing platform, a prefabricated hollow main column is connected to the grouting part, and the prefabricated hollow main column is connected with an iron tower base plate through foundation bolts. A 1 + X arrangement mode is adopted, a designer can select 4-9 anchor rods according to upper loads, the arrangement mode is more flexible and economical compared with an existing square arrangement mode, mechanical connection of the foundation bolts, the main column longitudinal steel bars and the anchor rods is achieved through the connecting steel plates, and compared with traditional connection achieved through anchoring force between the steel bars and concrete, the connection efficiency is improved. The force transmission mode is more direct, and the uplift bearing capacity of the foundation is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of overhead power transmission line engineering, and in particular to a 1+X type transmission line assembled anchor rod foundation structure and a construction method. Background Art

[0002] Traditional cast-in-place anchor foundations for power transmission lines are generally used in geological conditions with a thin overburden layer, such as upper soil and lower rock. They consist of three parts: anchor rods, caps, and main columns. The base plate is used to withstand the downward compressive load transmitted by the upper tower, while the upward pull load is primarily borne by the anchor rods embedded in the rock. The construction sequence is to excavate to the bottom elevation of the base plate, drill holes into the rock using an anchor drill rig, and then pour concrete or mortar and anchor rods into the rock holes. After the grouting solidifies, the anchor rods, concrete, and rock form a single unit. The base plate and main column reinforcement are then tied, anchor bolts are embedded, and concrete is poured. Construction is completed once the foundation reaches the required strength.

[0003] At present, most rock anchor foundations and construction methods still use the method of on-site reinforcement binding and pouring. The transportation of materials such as cement, sand, gravel, and steel bars is difficult, and it is easy to cause material waste and environmental pollution. The cast-in-place foundation requires on-site concrete maintenance, which is easily affected by the construction environment, resulting in concrete quality not meeting the expected standards. It also increases the manual labor on the construction site, which is not conducive to the promotion of mechanized construction of power transmission and transformation projects.

[0004] Currently developed prefabricated anchor foundations are mostly column-less, which doesn't work well with slightly deeper overburden on-site. Alternatively, they use steel, which doesn't meet durability requirements and is prone to corrosion, leading to failure. Other prefabricated anchor foundations utilize prefabricated caps and columns. While this reduces on-site labor, the heavy components make them difficult to transport and assemble.

[0005] The number of anchor rods in traditional anchor foundations is generally limited to two square anchor rod arrangements of 2×2 and 3×3. The number and arrangement of anchor rods are single. When selecting anchor rods according to the upper load in the design, it is impossible to ensure the accurate number, which easily leads to great waste.

[0006] In traditional construction, anchor bolting involves inserting anchor bars into drilled holes, filling the area around the bars with fine stone concrete or mortar, and then allowing the grout to solidify to form the anchor. Inadequate grouting around the anchor bars due to construction quality and other factors can result in the anchor bar's bearing capacity failing to meet design requirements, and its durability can also be affected.

[0007] Regarding this type of prefabricated foundation, there is a lack of relevant specifications or standards to guide the design.

[0008] Based on this, a 1+X type transmission line assembled anchor foundation structure and construction method are proposed. Summary of the Invention

[0009] The purpose of the present invention is to solve the above problems and to propose a 1+X type transmission line assembled anchor foundation structure and construction method.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions: A 1+X type transmission line assembled anchor foundation structure includes a prefabricated anchor, a groove-shaped prefabricated pedestal and a U-shaped prefabricated pedestal are connected to the prefabricated anchor, the upper end of the prefabricated anchor is connected to a connecting steel plate via a double nut, a grouting part is provided between the groove-shaped prefabricated pedestal and the U-shaped prefabricated pedestal, a prefabricated hollow main column is connected to the grouting part, and the prefabricated hollow main column is connected to an iron tower base plate via anchor bolts.

[0011] Preferably, the bottom plates of the trough-shaped prefabricated pedestal and the U-shaped prefabricated pedestal are provided with steel bar positioning holes, and the prefabricated anchor rods are connected to the positioning holes.

[0012] Preferably, two trough-shaped prefabricated caps are provided, and the U-shaped prefabricated cap is provided between the two trough-shaped prefabricated caps. Concave and convex shear grooves are provided on the inner side of the prefabricated cap along the height direction.

[0013] Preferably, the connecting steel plate is arranged in the grouting part, and grouting holes are opened at the top of the prefabricated hollow main column, the connecting steel plate and the center of the tower base plate.

[0014] Preferably, the surface of the prefabricated anchor rod is concave-convex.

[0015] Preferably, the anchor bolt is connected to a connecting strip, the connecting strip is connected to a connecting plate via screws, the connecting plate is connected to a sleeve, a telescopic column is slidably connected in the sleeve, one end of the telescopic column is connected to an embedded plate, an abutment frame is rotatably connected to the sleeve, and the other end of the abutment frame is rotatably connected to the telescopic column; The connecting plate is rotatably connected to a deflection block through a hinge frame, the deflection block is connected to an embedded plate through a connecting rope, one side of the deflection block is connected to a sleeve block, the connecting plate is connected to a pressing block through a spring, and the pressing block is connected to a storage rod and a plug column; The connecting plate is connected to a tube plate, a separation rod is slidably connected to the tube plate, and an abutment plate and a push bar are connected to the separation rod.

[0016] A construction method for a 1+X type transmission line assembled anchor foundation structure, using a 1+X type transmission line assembled anchor foundation structure, comprises the following steps: S1: Excavate to the depth of the precast trough cap height, use an anchor drill to complete the drilling of precast anchors, place the precast anchors and grout; S2: The top of the precast anchor rod passes through the pre-opened holes of the U-shaped precast cap and the trough-shaped precast cap, and the stress-bearing steel bars are inserted in the length direction of the construction joint between the trough-shaped precast cap and the U-shaped precast cap, and additional connecting steel bars are inserted into the steel bar positioning holes on both sides of the joint; S3: The prefabricated hollow main column, tower base plate, connecting steel plate and anchor bolts welded together in the factory are hoisted onto the U-shaped prefabricated cap and fixed. The top of the prefabricated anchor rod extends out of the connecting steel plate and is exposed to a certain height. The pad and nut are placed in sequence from the top. The nut at the top of the prefabricated anchor rod is fixed with a hollow hydraulic wrench, and a certain pre-tightening force is applied according to the force required; S4: Insert the steel bars on the top surface of the bottom plate from the reserved through-reinforcement holes on the side of the prefabricated hollow main column, penetrate the bottom plate and form a steel mesh with other steel bars on the top surface of the bottom plate, and pour grouting material from the grouting holes on the top of the prefabricated hollow main column until the top surface of the trough-shaped prefabricated pedestal, the prefabricated hollow main column, the construction joint and the hollow part are filled. When the grouting material reaches the required strength, complete the construction and backfill the bottom plate.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. This application utilizes high-strength, non-shrinkage cement-based grouting material, addressing the high transportation costs, waste, and environmental pollution associated with small quantities of commercial concrete and long distances. It also avoids the unreliable quality of on-site self-mixed concrete. Grouting can be carried out on-site simply by adding water and mixing according to the required mix ratio. Strength is achieved in 1-3 days, significantly shortening the construction period. This approach minimizes material waste and is environmentally friendly and pollution-free.

[0018] 2. This application retains the advantage of good durability of concrete structure by changing from cast-in-place to prefabricated assembly. The connecting steel plates, nuts, etc. are all wrapped in concrete to form a whole, avoiding the disadvantage of easy rust of traditional metal prefabricated structures.

[0019] 3. This application significantly reduces the weight of components by dividing and hollowing the components, and the final component weight is controlled within the range of 200-500kg, which is more convenient for long-distance transportation and on-site lifting.

[0020] 4. During on-site assembly, the components are assembled by simply tightening the nuts on the top surface of the steel plate with a hollow hydraulic wrench. No on-site welding or other operations are required, resulting in a higher degree of mechanization. The connecting steel bars are simply passed through the prefabricated holes and secured, making construction convenient.

[0021] 5. This application utilizes a 1+X layout, allowing designers to select 4-9 anchor rods based on the upper load. This is more flexible and economical than the previous 2×2 and 3×3 square layouts. Because the outer X anchor rods are arranged in a circular pattern around the outside of the main column, the anchor rods are equidistant from the main column, resulting in a more even and reasonable force distribution on each anchor rod. The mechanical connection between the anchor bolts, the main column longitudinal reinforcement, and the anchor rods is achieved through connecting steel plates. Compared to traditional connections that rely on the anchoring force between steel and concrete, this provides a more direct force transmission method and a higher foundation pullout bearing capacity.

[0022] 6. This application uses prefabricated anchor rods instead of anchor bars, thereby avoiding the anchor rod quality problems caused by misaligned anchor bars, inadequate grouting, etc. in traditional construction, and effectively improving the reliability and durability of the anchor rods. The prefabricated anchor rods are processed in the factory, and the quality can fully meet the design requirements. The on-site construction is simple. After the anchor rods are fully formed, the overall bearing capacity is basically the same as that of the cast-in-place anchor rods.

[0023] 7. This application adopts a deflection block structure, which can quickly unfold the embedded plate and embedded disc structure, thereby improving the structural stability of the anchor rod foundation structure connected to the ground. The deflection block structure can be folded, which improves the transportation and carrying convenience of this part of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic structural diagram of a prefabricated hollow main column connection according to an embodiment of the present invention is shown; Figure 2 A schematic structural diagram of a prefabricated anchor rod connection provided in an embodiment of the present invention is shown; Figure 3 It shows a schematic structural diagram of a connection point of connecting steel plates provided in an embodiment of the present invention; Figure 4 A schematic diagram of a prefabricated anchor rod structure provided in an embodiment of the present invention is shown; Figure 5 A schematic diagram of an on-site grouting structure of an anchor rod provided in accordance with an embodiment of the present invention is shown; Figure 6 It shows a schematic structural diagram of the connection portion of the connecting strips provided in accordance with an embodiment of the present invention; Figure 7 It shows a schematic structural diagram of the connection of the telescopic column provided in an embodiment of the present invention; Figure 8 A side structural schematic diagram of a tube sheet connection provided according to an embodiment of the present invention is shown.

[0025] Legend: 1. Prefabricated anchor rod; 2. Prefabricated hollow main column; 3. Grooved prefabricated pedestal; 4. U-shaped prefabricated pedestal; 5. Connecting steel plate; 6. Tower base plate; 7. Anchor bolt; 8. Grouting part; 9. Connecting strip; 10. Connecting plate; 11. Screw; 12. Deflection block; 13. Embedded plate; 14. Articulated frame; 15. Tube plate; 16. Telescopic column; 17. Embedded plate; 18. Casing; 19. Abutment frame; 20. Separation rod; 21. Abutment plate; 22. Pushing strip; 23. Sleeve block; 24. Insert column; 25. Pressing block; 26. Storage rod; 27. Spring. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention. Example

[0027] See also Figure 1-Figure 5 , the present invention provides a technical solution: A 1+X type transmission line assembled anchor foundation structure includes a prefabricated anchor rod 1, which is connected to a trough-shaped prefabricated pedestal 3 and a U-shaped prefabricated pedestal 4. The anchor rod arrangement is changed to a 1+X form, that is, X anchor rods are arranged in a ring around a central anchor rod, the number of anchor rods is more flexible, the anchor rods are more evenly stressed, and the arrangement is more reasonable. At the same time, the specifications and types of prefabricated components are further optimized. The upper end of the prefabricated anchor rod 1 is connected to a connecting steel plate 5 through a double nut, and a grouting part 8 is set between the trough-shaped prefabricated pedestal 3 and the U-shaped prefabricated pedestal 4. Each component can also serve as a structural outer mold, eliminating the manual operation processes such as on-site formwork and demoulding. Only grouting and setting of a small amount of connecting steel bars are required on site. The grouting part 8 is connected to a prefabricated hollow main column 2, and the prefabricated hollow main column 2 is connected to an iron tower base plate 6 through anchor bolts 7. While ensuring the durability of the foundation structure, the concrete components of the anchor rod foundation are split into components, which is convenient for factory prefabrication and on-site assembly.

[0028] Specifically, such as Figure 1 As shown, steel bar positioning holes are opened on the bottom plates of the trough-shaped prefabricated pedestal 3 and the U-shaped prefabricated pedestal 4, and the prefabricated anchor rods 1 are connected to the positioning holes. Through reasonable design, the components are further divided into blocks or hollowed, which reduces the weight of the prefabricated components and facilitates long-distance transportation and on-site assembly.

[0029] Specifically, such as Figure 2 As shown, two trough-shaped prefabricated caps 3 are provided, and the U-shaped prefabricated cap 4 is provided between the two trough-shaped prefabricated caps 3 .

[0030] Specifically, such as Figure 3 As shown, the connecting steel plate 5 is arranged in the grouting part 8, and grouting holes are opened at the top of the prefabricated hollow main column 2, the center of the connecting steel plate 5 and the tower base plate 6. High-strength non-shrinkage cement-based grouting material is used for the anchor rods, the hollow parts of the components and the joints. Compared with traditional fine stone concrete materials, it has early strength, quick drying, slight expansion, longer service life, more convenient and environmentally friendly on-site use.

[0031] This embodiment provides two prefabricated anchor rods with different shapes, specifically Figure 4 As shown, the surface of the prefabricated anchor rod 1 is concave and convex. The inserted anchor bar is replaced by the prefabricated anchor rod 1. During construction, the prefabricated anchor rod 1 is inserted into the anchor rod hole and the remaining part is grouted. The shape after grouting is as follows Figure 5 As shown, the construction quality and durability of the anchor rod can be improved. The surface of the precast anchor rod 1 is designed to be concave and convex. Before grouting, a concrete interface agent is applied to ensure that the interface bonding effect between the subsequent grouting and the precast anchor rod 1 is no less than the shear bearing capacity between the outer surface of the anchor rod and the rock formation, ensuring a reliable interface connection.

[0032] In summary, the present embodiment provides a method for constructing a 1+X type transmission line assembled anchor foundation structure. First, the ground needs to be excavated to the bottom elevation of the foundation slab. The anchor drilling rig completes the anchor drilling, places the prefabricated anchor 1, and grouts the anchor. After the anchor reaches the required strength, it is tested. Two trough-shaped prefabricated caps 3 are placed in the corresponding position of the foundation pit with the U-shaped prefabricated cap 4 as the center. The top of the prefabricated anchor rod 1 passes through the pre-opened hole on the prefabricated cap 3. A 50mm distance is left between the prefabricated caps as a construction joint. Along the length direction of the construction joint between the trough-shaped prefabricated cap 3 and the U-shaped prefabricated cap 4, the corresponding stress-bearing steel bars are inserted, and additional connecting steel bars are inserted into the steel bar positioning holes on both sides of the joint. The prefabricated hollow main column 2, the tower base plate 6, the connecting steel plate 5, the tower base plate 6 and the anchor bolts 7 are welded in the factory. Specifically, the top of the prefabricated hollow main column 2 is fixed to the tower base plate 6 and the column top through the exposed anchor bolts 7. The bottom of the longitudinal reinforcement of the prefabricated hollow main column 2, the bottom of the anchor bolts 7 and the connecting steel plate 5 are welded in the factory to form a whole, and are hoisted onto the trough-type prefabricated pedestal 3 and the U-type prefabricated pedestal 4 for temporary fixation. At this time, the top of the prefabricated anchor rod 1 extends out of the connecting steel plate 5 and is exposed at a predetermined height, and the pads and nuts are placed in sequence from the top.

[0033] Use a hollow hydraulic wrench to tighten the nut on the top of the prefabricated anchor rod 1 to ensure a tight connection between the prefabricated anchor rod 1 and the connecting steel plate 5; Insert the top surface steel bars of the bottom plate into the reserved through-bar holes on the side of the prefabricated hollow main column 2, passing through the entire bottom plate and forming a steel mesh together with other top surface steel bars of the bottom plate; Prepare the grouting material according to the grouting material instructions. Pour the mixed grouting material into the grouting port on the top of the prefabricated hollow main column 2 and flow out from the grouting hole of the connecting steel plate 5 until it fills the top surface of the trough-shaped prefabricated base 3 and the prefabricated hollow main column 2. The construction joint between the trough-shaped prefabricated base and the prefabricated hollow main column 2 and the hollow part of the prefabricated hollow main column 2 are finally connected as a whole through the grouting part 8. When the grouting material reaches the designed strength and the construction is completed, the bottom plate is backfilled. Example

[0034] See also Figure 6-Figure 8 The anchor rod foundation structure of this embodiment differs from that of Example 1 in that: The anchor bolt 7 is connected to a connecting bar 9, and two connecting bars 9 are provided. By setting the connecting bar 9 to connect an additional stabilizing structure, the stability of the anchor rod foundation structure is improved and the stability load of the anchor rod is reduced. The connecting bar 9 is connected to a connecting plate 10 by a screw 11. The connecting plate 10 is connected to a sleeve 18, and a telescopic column 16 is slidably connected in the sleeve 18. A telescopic structure is formed between the sleeve 18 and the telescopic column 16. When the telescopic column 16 is stored, the space occupancy rate can be reduced. When it is necessary to stabilize the connectivity of the anchor rod foundation structure, the telescopic column 16 needs to be in an extended state. One end of the telescopic column 16 is connected to an embedded plate 17. The embedded plate 17 can increase the force-bearing area, and then rely on the increase in the bearing soil area to improve the stability of the structural connection. An abutment frame 19 is rotatably connected to the sleeve 18, and the other end of the abutment frame 19 is rotatably connected to the telescopic column 16. When the telescopic column 16 contracts, the V-shaped angle of the abutment frame 19 is reduced, that is, when the abutment frame 19 is deformed, the telescopic column 16 starts to extend and retract synchronously. The connecting plate 10 is rotatably connected to the deflection block 12 through the hinge frame 14. When it is necessary to adjust the connection structure below the connecting plate 10 to expand, it is only necessary to pull the deflection block 12. When the connection structure below the connecting plate 10 is retracted, the space occupancy rate of the structure can be reduced, which is convenient for carrying and transportation. The deflection block 12 is connected to the embedded plate 13 through a connecting rope. The embedded plate 13 can further improve the firmness of the structure set under the ground. A sleeve block 23 is connected to one side of the deflection block 12. The connecting plate 10 is connected to a pressing block 25 through a spring 27. The pressing block 25 is connected to a storage rod 26 and a plug column 24. When it is necessary to cancel the limit of the plug column 24, it is only necessary to squeeze the spring 27. The connecting plate 10 is connected to the tube plate 15, and a separation rod 20 is slidably connected to the tube plate 15. The separation rod 20 is connected to the abutment plate 21 and the pushing bar 22. Two separation rods 20 are connected to a single tube plate 15, and the two separation rods 20 are symmetrically connected to the tube plate 15. When the deflection block 12 is flipped, the pushing bar 22 can be pushed to move in the direction of the tube plate 15. The synchronously moving abutment plate 21 can push the abutment frame 19 to deflect, thereby increasing its V-shaped angle, thereby pushing the telescopic column 16 to move downward. The operator presses the spring 27 to insert the plug 24 into the sleeve block 23, thereby limiting the deflection block 12 structure and simultaneously ensuring that the telescopic column 16 structure is fixed. At this time, the connecting bar 9 can be connected to the anchor bolt 7, and the structure connected to the other end of the connecting bar 9 is simultaneously buried under the ground, thereby forming a traction limit for the anchor rod and improving the stability of the anchor rod structure.

[0035] The above description of the embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A 1+X type transmission line assembled anchor foundation structure, comprising a prefabricated anchor (1), characterized in that: The prefabricated anchor rod (1) is connected to a trough-shaped prefabricated pedestal (3) and a U-shaped prefabricated pedestal (4); the upper end of the prefabricated anchor rod (1) is connected to a connecting steel plate (5) via a double nut; a grouting portion (8) is provided between the trough-shaped prefabricated pedestal (3) and the U-shaped prefabricated pedestal (4); the grouting portion (8) is connected to a prefabricated hollow main column (2); and the prefabricated hollow main column (2) is connected to an iron tower base plate (6) via anchor bolts (7).

2. A 1+X type transmission line assembled anchor foundation structure according to claim 1, characterized in that: Steel bar positioning holes are provided on the bottom plates of the trough-shaped prefabricated pedestal (3) and the U-shaped prefabricated pedestal (4), and the prefabricated anchor rods (1) are connected to the positioning holes.

3. The 1+X type transmission line assembled anchor foundation structure according to claim 1, characterized in that: Two trough-shaped prefabricated supports (3) are provided, and the U-shaped prefabricated support (4) is provided between the two trough-shaped prefabricated supports (3).

4. The 1+X type transmission line assembled anchor foundation structure according to claim 1, characterized in that: The connecting steel plate (5) is arranged in the grouting portion (8), and grouting holes are provided at the top of the prefabricated hollow main column (2), the connecting steel plate (5), and the center of the iron tower base plate (6).

5. The 1+X type transmission line assembled anchor foundation structure according to claim 1, characterized in that: The surface of the prefabricated anchor rod (1) is concave-convex.

6. The 1+X type transmission line assembled anchor foundation structure according to claim 1, characterized in that: The anchor bolt (7) is connected to a connecting strip (9), the connecting strip (9) is connected to a connecting plate (10) via a screw (11), the connecting plate (10) is connected to a sleeve (18), a telescopic column (16) is slidably connected in the sleeve (18), one end of the telescopic column (16) is connected to an embedded plate (17), the sleeve (18) is rotatably connected to an abutment frame (19), and the other end of the abutment frame (19) is rotatably connected to the telescopic column (16); The connecting plate (10) is rotatably connected to a deflection block (12) via a hinge frame (14); the deflection block (12) is connected to an embedded plate (13) via a connecting rope; one side of the deflection block (12) is connected to a sleeve block (23); the connecting plate (10) is connected to a pressing block (25) via a spring (27); and the pressing block (25) is connected to a receiving rod (26) and an insertion column (24); The connecting plate (10) is connected to a tube plate (15), a separation rod (20) is slidably connected to the tube plate (15), and the separation rod (20) is connected to an abutment plate (21) and a push bar (22).

7. A construction method for a 1+X type transmission line assembled anchor foundation structure, using the 1+X type transmission line assembled anchor foundation structure according to claim 1, characterized in that: The following steps are involved: S1: excavate to the depth of the trough-shaped prefabricated cap (3), use an anchor drilling machine to complete the drilling of the prefabricated anchor rod (1), place the prefabricated anchor rod (1) and grout; S2: The top of the prefabricated anchor rod (1) passes through the pre-opened holes of the U-shaped prefabricated pedestal (4) and the trough-shaped prefabricated pedestal (3), and the stress-bearing steel bars are inserted in the length direction of the construction joint between the trough-shaped prefabricated pedestal (3) and the U-shaped prefabricated pedestal (4), and additional connecting steel bars are inserted into the steel bar positioning holes on both sides of the joint; S3: The prefabricated hollow main column (2), the tower base plate (6), the connecting steel plate (5) and the anchor bolts (7) welded together in the factory are hoisted onto the U-shaped prefabricated pedestal (4) and fixed. The top of the prefabricated anchor rod (1) extends out of the connecting steel plate (5) and is exposed to a certain height. The pad and nut are placed in sequence from the top. The top nut of the prefabricated anchor rod (1) is fixed with a hollow hydraulic wrench, and a pre-tightening force is applied according to the force required. S4: Insert the steel bars on the top surface of the bottom plate from the reserved through-reinforcement holes on the side of the prefabricated hollow main column (2), penetrate the bottom plate and form a steel mesh with other steel bars on the top surface of the bottom plate, and pour grouting material from the grouting holes on the top of the prefabricated hollow main column (2) until the top surface of the trough-shaped prefabricated pedestal (3), the prefabricated hollow main column (2), the construction joint and the hollow part are filled. When the grouting material reaches the required strength, the construction is completed and the bottom plate is backfilled.

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