Fabricated stainless steel high performance concrete composite column

Abstract

The application discloses an assembled stainless steel high-performance concrete composite column body, which comprises a stainless steel high-performance concrete composite formwork and core concrete poured into an inner cavity formed by the stainless steel high-performance concrete composite formwork; the stainless steel high-performance concrete composite formwork is formed into a square frame structure by two wrapping formworks and two fastening formworks; and the wrapping formworks and the fastening formworks are fixed by being pulled tightly through preinstalled fasteners. The formwork of the application is connected by a connection mode of factory prefabrication and on-site dry assembly, field welding is avoided, construction difficulty is significantly reduced, and split hoisting construction can be realized, so that the single-time hoisting weight is reduced.

Description

Technical Field

[0001] This invention relates to the field of nuclear chemical and marine engineering structural technology, specifically to a prefabricated stainless steel high-performance concrete composite column. Background Technology

[0002] In engineering construction, nuclear chemical and marine engineering structures must meet stringent requirements for corrosion resistance, cleanliness, and radiation protection, and stainless steel is commonly used as the lining material for these structures. To control costs, thin stainless steel plates of about 1-3 mm are typically used as outer formwork, with concrete poured directly onto their surface. However, the stainless steel plates themselves have low rigidity, making them prone to defects such as bulging and deformation during concrete pouring and use. This not only affects the appearance quality but may also weaken their protective performance and reduce the overall durability of the structure.

[0003] To enhance the rigidity of the stainless steel cladding and prevent bulging during subsequent concrete pouring, an ultra-high performance concrete layer is introduced to form a composite shell structure. However, existing solutions still have significant drawbacks: the connection between the high-performance concrete layer and the stainless steel plate relies on on-site welding of shear members, which can damage the materials' corrosion resistance due to the high temperatures at the construction site, and construction in nuclear clean areas is strictly limited; using stainless steel for all shear members would be too costly, while using carbon steel presents technical challenges in welding dissimilar materials. These factors limit the application of this composite structure in high-standard projects.

[0004] Therefore, there is an urgent need for a new type of stainless steel high-performance concrete composite formwork system that can completely avoid on-site welding, ensure construction cleanliness, and at the same time have high rigidity and high economy, so as to meet the stringent requirements of special engineering projects such as nuclear chemical industry and marine engineering for structural performance and construction quality.

[0005] In the prior art, for example, a UHPC-stainless steel composite formwork structure and construction method with external concrete is disclosed in CN119531566A. It adopts a UHPC-stainless steel composite formwork and sets staggered hole PBL shear keys to realize the collaborative work between stainless steel and concrete.

[0006] However, the aforementioned existing technologies mainly focus on the construction and organization of cylindrical ventilation shaft structures. Their combined formwork and connection systems are not specifically designed for the assembly structure described in this application, which is "a closed rectangular cylindrical structure formed by assembling multiple rectangular formwork units and used for columns." At the same time, their PBL shear connection structure does not provide the overall solution adopted in this application, which is "a composite setting of stainless steel PBL segments and carbon steel PBL segments, combined with high-performance concrete layer height control to expose the carbon steel segments and interlock with the core concrete." Therefore, there is still room for further improvement in terms of corrosion resistance, economy, and compatibility with assembly construction.

[0007] For example, the paper "Mechanical Behavior in Perfobond RibShear Connector with UHPC-Steel Composite Structure with Coarse Aggregate" published by Maojun Duan et al. (KSCE Journal of Civil Engineering, 2020, DOI: 10.1007 / s12205-020-0923-3) conducted experimental and numerical analysis on the mechanical behavior of PBL shear connectors in UHPC-steel composite structures.

[0008] However, this literature pertains to the study of the stress performance of connectors, focusing on the influence of PBL connector parameters on load-bearing capacity and deformation. It does not address the specific structure and construction method of the "stainless steel high-performance concrete composite mold shell segmented assembly into columns" described in this application. Nor does it propose the complete structure of "heterogeneous material segmented composite PBL (stainless steel segment / carbon steel segment) + staggered holes and graded hole diameter matching (difference between high-performance concrete layer and core concrete aggregate)" adopted in this application. Therefore, it cannot solve the comprehensive technical problems addressed in this application, such as the tendency of thin stainless steel cladding to bulge during the pouring stage, and the need to simultaneously consider corrosion resistance and economy. Summary of the Invention

[0009] In order to overcome the defects of the existing technology, the present invention aims to provide a prefabricated stainless steel high-performance concrete composite column. The formwork of the composite column adopts a connection method of factory prefabrication and on-site dry assembly, avoiding on-site welding, significantly reducing the construction difficulty, and at the same time enabling split hoisting construction, reducing the weight of a single hoisting.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A prefabricated stainless steel high-performance concrete composite column includes a stainless steel high-performance concrete composite mold shell and core concrete poured into the inner cavity formed by the stainless steel high-performance concrete composite mold shell. The stainless steel high-performance concrete composite formwork is assembled from two wrapping formworks and two fastening formworks to form a square frame structure. The wrapping formworks and the fastening formworks are tightened and fixed by pre-installed fasteners.

[0011] Both the wrapping mold and the fastening mold include a stainless steel plate and a high-performance concrete layer poured inside the stainless steel plate. Several staggered-hole composite PBL shear members are welded to the inner side of the stainless steel plate. The staggered hole composite PBL shear member includes a stainless steel segment PBL welded to the stainless steel plate and a carbon steel segment PBL connected to the stainless steel segment PBL. The stainless steel segment PBL has a first hole, and the carbon steel segment PBL has a second hole.

[0012] The pre-installed fasteners include high-strength screws, high-strength nuts, and washers. The high-strength screws are pre-embedded in the fastening mold along the direction perpendicular to the column height and are fixed as the high-performance concrete layer of the fastening mold is poured. The two ends of the high-strength screws extend from opposite sides of the fastening mold. The stainless steel plate enclosing the mold shell has a through hole at the position corresponding to the high-strength screw. A PVC pipe coaxially connected to the through hole is pre-embedded in the high-performance concrete layer enclosing the mold shell. The length of the PVC pipe is the same as the thickness of the high-performance concrete layer. The two ends of the high-strength screw pass through the through holes and PVC pipes of the corresponding wrapping mold shells and extend out to the outside of the wrapping mold shells. The protruding end is fitted with the gasket and threadedly connected to the high-strength nut. By tightening the high-strength nut, the wrapping mold shell clamps and pulls the fastening mold shell to form a closed rectangular cylindrical structure. After the stainless steel high-performance concrete composite mold shell is assembled, the core concrete is poured into the inner cavity to form the composite column.

[0013] Both the wrapping mold and the fastening mold include a stainless steel plate and a high-performance concrete layer cast on its inner surface; the high-performance concrete layer fills the spaces between the staggered composite PBL shear members, and its height is the same as the height of the stainless steel PBL segment during casting, so that the carbon steel PBL segment is exposed outside the high-performance concrete layer.

[0014] The material of the high-performance concrete layer is selected from one of ultra-high performance concrete (UHPC), high-strength concrete, or polyurethane concrete.

[0015] The stainless steel section PBL has a first hole, and the carbon steel section PBL has a second hole; the diameter of the second hole is larger than the diameter of the first hole, and the first hole and the second hole are staggered along the length of the shear member, and the distance between adjacent holes is 50~100mm.

[0016] The core concrete is equipped with square spiral stirrups.

[0017] A composite formwork unit for the stainless steel high-performance concrete composite column includes two longer wrapping formworks and two shorter fastening formworks. Both the wrapping mold and the fastening mold are made of stainless steel plate and a high-performance concrete layer cast on its inner surface. The inner surface of the stainless steel plate is welded with several staggered composite PBL shear members extending along the column height direction. The casting height of the high-performance concrete layer is the same as the height of the stainless steel PBL section, so that the carbon steel PBL section is exposed outside the high-performance concrete layer. Multiple sets of through holes are opened on the stainless steel plate that wraps the mold shell. A PVC pipe coaxially connected with the through holes is pre-embedded in the high-performance concrete layer that wraps the mold shell to form a reserved through hole for the high-strength screw. Multiple sets of high-strength screws are pre-embedded in the fastening mold shell. The high-strength screws are arranged perpendicular to the column height, and the two ends of each set of high-strength screws extend from opposite sides of the fastening mold shell. During assembly, the high-strength screws extending from the fastening mold shell are inserted into the through holes and PVC pipes of the corresponding wrapping mold shell, and locked on the outside of the wrapping mold shell by washers and high-strength nuts, so that the wrapping mold shell clamps and pre-tightens the fastening mold shell.

[0018] A construction method for a stainless steel high-performance concrete composite column as described above includes the following steps: S1: Create the wrapping mold; Weld staggered-hole composite PBL shear members to the inner surface of the stainless steel plate enclosing the mold shell, and open through holes at the positions corresponding to the high-strength screws; before pouring the high-performance concrete layer enclosing the mold shell, fix the PVC pipe at the position corresponding to the through hole, so that the PVC pipe and the through hole are coaxially connected; then pour high-performance concrete between adjacent stainless steel PBL sections to form a high-performance concrete layer, and obtain the enclosing mold shell after curing. S2: Make a fastening mold shell; Weld staggered-hole composite PBL shear members to the inner surface of the stainless steel plate of the fastening mold shell; before pouring the high-performance concrete layer of the fastening mold shell, fix the high-strength screws in the fastening mold shell according to the design position, so that the high-strength screws are arranged in a direction perpendicular to the column height, and the two ends extend from the opposite sides of the fastening mold shell; then pour high-performance concrete between adjacent stainless steel PBL sections and cure it to obtain the fastening mold shell with embedded high-strength screws. S3: Assembled mold shell; Two wrapping mold shells extending along the column height are respectively used as the two opposite long sides of the rectangular cross section, and two fastening mold shells are respectively used as the two opposite short sides of the rectangular cross section. They are joined together in a "two long sides clamping two short sides" manner to form a rectangular cylindrical structure, so that the high-strength screws extending from both sides of the fastening mold shell are respectively inserted into the through holes of the corresponding wrapping mold shell and the PVC pipe. S4: Locking and securing; Washers are sequentially fitted onto the protruding ends of the high-strength screws on the outside of the mold shell and high-strength nuts are tightened to clamp and tighten the mold shell, forming a closed rectangular cylindrical structure. S5: Place the steel cage; According to the design requirements, the steel cage is tied, and the square spiral stirrups are fixed to the longitudinal bars to keep the longitudinal bars at a fixed spacing and position. The tied steel cage is then placed into the rectangular cylindrical structure formed by the formwork. S6: Pour the core concrete; Core concrete is poured into the rectangular cylindrical cavity formed by the mold shell, compacted by vibration and cured to form the composite column.

[0019] The beneficial effects of this invention are: (1) High-strength screws, high-strength nuts and washers are used on the construction site to achieve prefabricated dry connection, avoiding on-site welding. This not only reduces the difficulty of construction and improves the construction speed and quality, but also meets the construction requirements of the nuclear clean area. (2) The high-performance concrete layer and the thin stainless steel plate are firmly bonded together by composite PBL, which improves the overall rigidity of the mold shell and effectively prevents the stainless steel plate from bulging and deforming when the core concrete is poured. (3) The composite PBL shear component design not only improves the interfacial performance between materials and ensures the reliability of the connection, but also significantly reduces the material cost; (4) The formwork can be constructed by splitting and hoisting each piece, which significantly reduces the weight of a single hoisting and lowers the difficulty of hoisting construction. Attached Figure Description

[0020] Figure 1 Schematic diagram of the cross-section of a stainless steel high-performance concrete formwork column. Figure 2 Schematic diagram of stainless steel high-performance concrete formwork assembly Figure 3 Schematic diagram of a single-piece encapsulated mold shell In the diagram, 1. Stainless steel high-performance concrete composite formwork; 11. Encasing formwork; 111. Through hole; 12. Fastening formwork; 121. PVC pipe; 122. High-strength bolt; 13. Stainless steel plate; 14. High-performance concrete layer; 2. Pre-installed fasteners; 21. High-strength nut; 22. Washer; 3. Staggered hole composite PBL shear member; 31. Stainless steel PBL segment; 311. First hole; 32. Carbon steel PBL segment; 321. Second hole; 4. Longitudinal reinforcement; 5. Square spiral stirrup; 6. Core concrete. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings.

[0022] A stainless steel high-performance concrete composite mold shell is divided into a wrapping mold shell 11 and a fastening mold shell 12, both of which are composed of a thin stainless steel plate 13 and a high-performance concrete layer 14. The inner surface of the plate is provided with several composite PBL shear members 3 arranged along the column height direction. The composite PBL shear member 3 is composed of a stainless steel section welded to the stainless steel plate and a continuous carbon steel section. The two sections are staggered with holes spaced at 50~100mm. The hole diameter on the stainless steel section is smaller than that on the carbon steel section, so as to adapt to the particle size difference between the high-performance concrete slurry and the core concrete aggregate. The material of the high-performance concrete layer 14 can be selected according to the actual project requirements for strength, corrosion resistance, and cost. The material includes, but is not limited to, ultra-high performance concrete (UHPC), ordinary high-strength concrete, or polyurethane concrete. UHPC is suitable for nuclear and chemical engineering projects with extremely high requirements for corrosion resistance and strength; ordinary high-strength concrete is suitable for conventional high-rise buildings; and polyurethane concrete is suitable for marine engineering projects with special requirements for toughness and impact resistance.

[0023] The high-performance concrete layer 14 is poured between the shear members, and its height is flush with the stainless steel section, exposing the carbon steel section. Before pouring high-performance concrete, several high-strength screws are pre-embedded inside the fastening mold shell. The high-strength screws are arranged perpendicular to the column height, and after the casting is completed, their two ends extend from opposite sides of the fastening mold shell. The mold shell is provided with a through hole at the position corresponding to the high-strength screw, and a PVC pipe is pre-embedded at the corresponding position before pouring high-performance concrete to form a screw passage channel coaxially connected with the through hole; A composite column constructed using the aforementioned mold shell is formed by joining two wrapping mold shells and two fastening mold shells in a "two long clamping two short" manner; The high-strength bolts pre-embedded and extended on both sides of the fastening mold shell are inserted into the corresponding through holes and PVC pipes on both sides of the mold shell to achieve the positioning and assembly of the outer mold of the mold shell column; A washer is placed at the protruding end of the high-strength screw on the outside of the mold shell and the high-strength nut is tightened to clamp and tighten the mold shell, forming a closed rectangular cylindrical structure. Inside the assembled rectangular cylindrical formwork, a steel cage with tied reinforcement bars is placed. Square spiral stirrups 5 can be configured according to the design to further enhance the overall performance of the formwork column. 6. Core concrete was poured inside the cylindrical structure.

[0024] Example: Construction of a stainless steel high-performance concrete composite formwork and column for structural columns in nuclear chemical and marine engineering.

[0025] Reference Figures 1 to 3The manufacturing and assembly process of the stainless steel high-performance concrete composite mold shell provided in this specific embodiment is as follows: First, the mold shell unit is fabricated. A 1-3mm thick 304 stainless steel plate is used as stainless steel plate 13. Several staggered-hole composite PBL shear members 3 are welded onto its inner surface along the column height direction according to design requirements. The stainless steel section PBL31 is spot-welded to the stainless steel plate 13 using argon arc welding, while the carbon steel section PBL32, made of Q235B steel, is pre-connected to the stainless steel section PBL31 in the factory using reliable processes such as friction welding. The mold shell consists of two types: a wrapping mold shell 11 and a fastening mold shell 12. In this process, the stainless steel plate 13 enclosing the formwork 11 has through holes 111 at positions corresponding to the high-strength screws 122, and PVC pipes 121 are pre-embedded at corresponding positions before the high-performance concrete layer 14 is poured, so that the PVC pipes 121 and the through holes 111 are coaxially connected. The fastening formwork 12 also has high-strength screws 122 pre-embedded at designed positions before the high-performance concrete layer 14 is poured, so that the high-strength screws 122 are arranged perpendicular to the column height, and their two ends extend from opposite sides of the fastening formwork 12. Subsequently, high-performance concrete 14 is poured between the staggered-hole composite PBL shear members 3, with the pouring height flush with the stainless steel section PBL 31. After curing, the enclosing formwork 11 and the fastening formwork 12 are formed.

[0026] Next, on-site assembly is carried out. The mold shells are hoisted to the construction position in sections, and two wrapping mold shells 11 and two fastening mold shells 12 are joined together using a "two long clamps two short" method to form a rectangular cylindrical structure. The high-strength screws 122 extending from both sides of the fastening mold shell 12 pass through the through holes 111 and PVC pipes 121 of the corresponding wrapping mold shells 11 and extend outwards from the outside of the wrapping mold shells 11. On the outside of the mold shells, washers 22 are fitted onto the protruding ends of the high-strength screws 122 and high-strength nuts 21 are tightened, thereby clamping and pulling the fastening mold shells 12 tightly with the wrapping mold shells 11, forming a closed rectangular cylindrical structure. The "two long clamps two short" method means that the two wrapping mold shells arranged along the long side of the column section and the two fastening mold shells arranged along the short side of the column section are interlocked, so that the high-strength screws are passed through along the cross-sectional direction and form a uniform clamping force on the four mold shells. This arrangement helps reduce the number of seams on the long side, improves the continuity of the exposed stainless steel surface, and facilitates the installation and positioning of high-strength bolts.

[0027] Next, the reinforcing steel cage is tied. According to design requirements, 12 HRB400 grade steel bars are used as longitudinal reinforcement 4, fixed on the tying platform at the four corners and three-thirds points of each side of the rectangular section, ensuring they are parallel and accurately spaced. This makes the longitudinal reinforcing steel bars of the rectangular section more evenly distributed along the perimeter, improving the stress and crack control effect under the combined action of axial compression and bending moment, and providing a reliable longitudinal skeleton for the square spiral stirrups to form a stable constraint boundary, thereby improving the overall ductility and stability of the column. Subsequently, starting from one end of the reinforcing cage, the stirrups are spirally advanced along the longitudinal reinforcement, forming a continuous spiral constraint structure. The square spiral stirrups are tied and fixed at their inflection points using binding wire, completing the tying of the square spiral stirrups 5. The square spiral stirrups are continuously set along the column height, forming a more uniform and continuous lateral constraint on the core concrete, reducing the risk of local buckling and brittle cracking, and improving the column's ductility and energy dissipation capacity. After the reinforcing cage is tied and checked for errors, it can be hoisted into the formwork, preparing for the subsequent core concrete pouring.

[0028] Finally, the core concrete is poured. Self-compacting core concrete 6 is poured into the rectangular cavity formed by the formwork, and carefully vibrated to ensure compaction, especially ensuring that the core concrete 6 fully interlocks with the stainless steel high-performance concrete composite formwork 1 through the carbon steel section PBL32. After pouring, it is cured as required to ultimately form a high-performance composite column.

[0029] This specific embodiment clearly illustrates the entire process of the invention, from mold shell fabrication to overall molding, through complete technological steps, fully demonstrating the feasibility, reliability, and superiority of the invention. The above description is merely a specific embodiment of the invention, but the scope of protection of the invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this invention should be included within the scope of protection of this invention.

Claims

1. A prefabricated stainless steel high-performance concrete composite column, characterized in that, It includes a stainless steel high-performance concrete composite mold shell (1) and a core concrete (6) poured into the inner cavity formed by the stainless steel high-performance concrete composite mold shell (1). The stainless steel high-performance concrete composite mold shell (1) is assembled from two wrapping mold shells (11) and two fastening mold shells (12) to form a square frame structure. The wrapping mold shell (11) and the fastening mold shell (12) are tightened and fixed by pre-installed fasteners (2).

2. The prefabricated stainless steel high-performance concrete composite column according to claim 1, characterized in that, Both the wrapping mold (11) and the fastening mold (12) include a stainless steel plate (13) and a high-performance concrete layer (14) poured inside the stainless steel plate (13). Several staggered hole composite PBL shear members (3) are welded to the inside of the stainless steel plate (13). The staggered hole composite PBL shear member (3) includes a stainless steel section PBL (31) welded to the stainless steel plate (13) and a carbon steel section PBL (32) connected to the stainless steel section PBL (31). The stainless steel section PBL (31) is provided with a first hole (311) and the carbon steel section PBL (32) is provided with a second hole (321).

3. The prefabricated stainless steel high-performance concrete composite column according to claim 2, characterized in that, The pre-installed fastener (2) includes a high-strength screw (122), a high-strength nut (21), and a washer (22). The high-strength screw (122) is embedded in the fastening mold (12) along the direction perpendicular to the column height and is fixed as the high-performance concrete layer (14) of the fastening mold (12) is poured. The two ends of the high-strength screw (122) extend from the opposite sides of the fastening mold (12). The stainless steel plate (13) of the mold shell (11) has a through hole (111) at the position corresponding to the high-strength screw (122). A PVC pipe (121) coaxially connected to the through hole (111) is pre-embedded in the high-performance concrete layer (14) of the mold shell (11). The length of the PVC pipe (121) is the same as the thickness of the high-performance concrete layer (14). The two ends of the high-strength screw (122) pass through the through hole (111) and PVC pipe (121) of the corresponding wrapping mold (11) and extend out to the outside of the wrapping mold (11). The protruding end is fitted with the gasket (22) and threadedly connected to the high-strength nut (21). By tightening the high-strength nut (21), the wrapping mold (11) clamps and pulls the fastening mold (12) to form a closed rectangular cylindrical structure.

4. A prefabricated stainless steel high-performance concrete composite column according to claim 3, characterized in that, The core concrete (6) is poured into the inner cavity of the stainless steel high-performance concrete composite mold (1) to form the composite column. The core concrete (6) is provided with square spiral stirrups (5).

5. A prefabricated stainless steel high-performance concrete composite column according to claim 3, characterized in that, Both the wrapping mold (11) and the fastening mold (12) include a stainless steel plate (13) and a high-performance concrete layer (14) cast on its inner surface; the high-performance concrete layer (14) fills between the staggered hole composite PBL shear members (3), and its height is the same as the height of the stainless steel segment PBL (31) during casting, so that the carbon steel segment PBL (32) is exposed outside the high-performance concrete layer (14).

6. A prefabricated stainless steel high-performance concrete composite column according to claim 5, characterized in that, The material of the high-performance concrete layer (14) is selected from one of ultra-high performance concrete, high-strength concrete or polyurethane concrete.

7. A prefabricated stainless steel high-performance concrete composite column according to claim 2, characterized in that, The stainless steel section PBL (31) has a first hole (311) and the carbon steel section PBL (32) has a second hole (321); the diameter of the second hole (321) is larger than the diameter of the first hole (311), and the first hole (311) and the second hole (321) are staggered along the length of the shear member, and the distance between adjacent holes is 50~100mm.

8. A construction method for a stainless steel high-performance concrete composite column as described in any one of claims 2-7, characterized in that, Includes the following steps: S1: Weld staggered hole composite PBL shear member (3) on the inner surface of stainless steel plate (13) covering the mold shell (11), and open through hole (111) at the position corresponding to the high strength screw (122); Before pouring the high performance concrete layer (14) covering the mold shell (11), fix PVC pipe (121) at the position corresponding to the through hole (111) so that the PVC pipe (121) and the through hole (111) are coaxially connected; then pour high performance concrete between adjacent stainless steel PBL (31) segments to form a high performance concrete layer (14), and obtain the mold shell (11) after curing. S2: Weld staggered hole composite PBL shear member (3) on the inner surface of the stainless steel plate (13) of the fastening mold (12); Before pouring the high-performance concrete layer (14) of the fastening mold (12), fix the high-strength screw (122) in the fastening mold (12) according to the design position, so that the high-strength screw (122) is arranged in a direction perpendicular to the column height, and both ends extend from the opposite sides of the fastening mold (12); then pour high-performance concrete between adjacent stainless steel PBL (31) sections and cure it to obtain the fastening mold (12) with embedded high-strength screw (122). S3: Two wrapping mold shells (11) extending along the column height direction are respectively used as the two opposite long sides of the rectangular cross section, and two fastening mold shells (12) are respectively used as the two opposite short sides of the rectangular cross section. They are joined together to form a rectangular cylindrical structure by using the two long sides clamping the two short sides. The high-strength screws (122) extending from both sides of the fastening mold shell (12) are respectively inserted into the through holes (111) and PVC pipes (121) of the corresponding wrapping mold shells (11). S4: Place washers (22) on the protruding end of the high-strength screw (122) on the outside of the outer side of the mold shell (11) and tighten the high-strength nut (21) so that the mold shell (11) clamps and pulls the mold shell (12) tightly to form a closed rectangular cylindrical structure. S5: Tie the steel cage according to the design requirements, fix the square spiral stirrups (5) and the longitudinal bars (4) to keep the longitudinal bars (4) at a fixed spacing and position, and put the tied steel cage into the rectangular cylindrical structure composed of the mold shell; S6: Pour core concrete (6) into the rectangular cylindrical cavity formed by the mold shell, vibrate and compact it, and cure it to form the composite column.

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