A composite reinforcing structure and method for an H-shaped steel column of an in-service plant building

Abstract

The application relates to a composite reinforcing structure and method for an H-shaped steel column of an in-service plant, which comprises the following steps: H-shaped steel column surface cleaning; steel reinforcement framework and H-shaped steel column 1 combined structure manufacturing; ultra-high performance concrete jet pouring; and fiber reinforced composite material encapsulation protective layer construction. The beneficial effects of the application are as follows: the steel reinforcement connecting rod linear section is provided with a groove, the steel reinforcement connecting rod is clamped on the stud nail through the groove and the stud nail to realize preliminary positioning and improve positioning accuracy; the steel reinforcement connecting rod two end bending sections are connected with H-shaped steel column flanges to realize secondary fixing; the stud nail shear connector and the steel reinforcement connecting rod double mechanical biting cooperation are adopted to ensure reliable force transmission between the H-shaped steel and the ultra-high performance concrete layer; the steel reinforcement framework cooperates with the stud nail to constrain the core steel, improves overall bending stiffness and stability; and the high toughness of the ultra-high performance concrete and the constraint effect of the fiber reinforced composite material are combined to make the component have good deformation capacity and energy dissipation capacity.

Description

Technical Field

[0001] This invention belongs to the field of building reinforcement and renovation engineering technology, and particularly relates to a composite reinforcement structure and method for H-shaped steel columns in in-service factory buildings. Background Technology

[0002] In recent years, with increasing age, a number of buildings, represented by old steel-structured factory buildings, are prone to corrosion of their columns, beams, and other components under the combined effects of the natural and industrial production environments. Equipment impacts during production, the impact loads from crane operation, and long-term exposure to uneven loads cause slight bending deformation in some H-shaped steel columns. Under certain special working conditions, the lateral displacement of the column tops in the overall factory structure increases, requiring strengthened lateral restraint. Furthermore, the factory buildings lack dedicated fire protection facilities, and the H-shaped steel columns cannot effectively prevent the spread of fire in the event of a fire, posing a significant fire safety hazard. To address these issues, post-construction reinforcement and renovation methods are often adopted to improve structural load-bearing capacity and stability, limit structural deformation, and enhance the structure's corrosion resistance and fire resistance.

[0003] Adhesive steel plates are prone to failure. Steel-bonded reinforcement relies on structural adhesive, but under actual stress, the adhesive is subjected to tensile and shear stress. Vertical deformation can cause the adhesive layer to crack, weakening the bond strength. In addition, steel plates are prone to corrosion, further reducing the reinforcement effect. Construction quality is highly dependent. The reinforcement plan has extremely high requirements for design and construction quality. Any mistake may cause the reinforced structure to fail to meet safety requirements, and traditional methods are difficult to adapt quickly to complex construction needs. Increased self-weight and high maintenance costs. Traditional reinforcement often uses steel or steel plates, which significantly increases the self-weight of the structure, making transportation and installation difficult. At the same time, regular anti-corrosion treatment is required, resulting in high maintenance costs.

[0004] Therefore, there is an urgent need to design a composite reinforcement structure and method for H-shaped steel columns in in-service factory buildings to overcome the defects of traditional construction and explore innovative methods that can improve load-bearing capacity without affecting normal use. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a composite reinforcement structure and method for H-shaped steel columns in in-service factory buildings.

[0006] The construction method for this composite reinforcement structure for H-shaped steel columns in in-service factory buildings is characterized by the following steps: S1 and H-shaped steel column surface cleaning; S2. Fabrication of the combined structure of the reinforcing steel frame and H-shaped steel column 1: Bend both ends of the reinforcing steel connecting rod and set a groove in the middle section; weld studs to the surface of the web of the H-shaped steel column, and place the reinforcing steel connecting rod on the studs to secure the grooves and studs; weld both ends of the reinforcing steel connecting rod to the flange surface of the H-shaped steel column; weld longitudinal reinforcing bars between the reinforcing steel connecting rods to form a reinforcing steel frame; S3. Ultra-high performance concrete spraying: Ultra-high performance concrete is sprayed in layers between the flanges and web of the H-shaped steel column. S4. Construction of fiber-reinforced composite material encapsulation protective layer: Wrap the H-shaped steel column with fiber-reinforced composite material.

[0007] Preferably, in step S2, the studs are evenly distributed along the height direction of the H-shaped steel column, and the studs are oriented perpendicular to the web of the H-shaped steel column and parallel to the flange of the H-shaped steel column.

[0008] Preferably, in step S2, the two ends of the reinforcing bar connecting rod are bent sections, and the middle part of the reinforcing bar connecting rod is a straight section; the bent sections at both ends of the reinforcing bar connecting rod are symmetrically welded to the flange surfaces on both sides of the H-shaped steel column; the longitudinal reinforcing bars are welded between the straight sections of the reinforcing bar connecting rod, and the longitudinal reinforcing bars are parallel to the web and flanges of the H-shaped steel column and perpendicular to the straight sections of the reinforcing bar connecting rod.

[0009] Preferably, in step S2, both the steel bar connecting rod and the longitudinal steel bar are ribbed steel bars.

[0010] Preferably, step S3 also includes the following steps: S31. Base treatment: Remove the loose and weak ultra-high performance concrete and wash the ultra-high performance concrete. S32. Shotcrete construction: Shotcrete ultra-high performance concrete in layers, with the interval between layers controlled before the initial setting of the current ultra-high performance concrete layer; repeat steps S31 and S32 until the ultra-high performance concrete covers the steel reinforcement skeleton. S33. Curing treatment: After the ultra-high performance concrete is sprayed, cover it for moisturizing and curing.

[0011] Preferably, in step S3, ultra-high performance concrete is sprayed and poured within the space formed by the interlocking steel plates surrounding the H-shaped steel column.

[0012] Preferably, in step S3, the spliced ​​steel plates are U-shaped, and the two sides of the spliced ​​steel plates are provided with bent sections with bolt holes. The bent sections of the two spliced ​​steel plates are attached to each other and fixed by bolts.

[0013] Preferably, step S3 includes applying an interface agent to the inner surface of the flange and the web surface of the H-shaped steel column.

[0014] Preferably, step S4 is followed by applying a weather-resistant protective coating to the outer surface of the fiber-reinforced composite material encapsulation protective layer.

[0015] This composite reinforcement structure for H-shaped steel columns in in-service factory buildings, constructed using the aforementioned method, comprises an H-shaped steel column, a steel reinforcement cage, ultra-high performance concrete, and fiber-reinforced composite material. The web of the H-shaped steel column is welded with studs. The steel reinforcement cage includes steel connecting rods and longitudinal reinforcing bars. The connecting rods have bent ends and a straight section in the middle, with grooves on the straight section. The connecting rods are secured to the studs via these grooves. The bent ends of the connecting rods are symmetrically welded to the flanges on both sides of the H-shaped steel column, and the longitudinal reinforcing bars are welded between the straight sections of the connecting rods. The ultra-high performance concrete is poured between the web and flanges of the H-shaped steel column. The fiber-reinforced composite material covers the H-shaped steel column.

[0016] The beneficial effects of this invention are: 1) The straight section of the reinforcing bar connecting rod of the present invention is provided with a groove. When installing the reinforcing bar connecting rod, it is secured to the stud through the groove, and the reinforcing bar connecting rod is placed on the stud to achieve initial positioning and improve positioning accuracy. Secondary fixing is achieved by connecting the bent sections at both ends of the reinforcing bar connecting rod to the flange of the H-shaped steel column. The stud and the reinforcing bar connecting rod form a spatial truss, so that the ultra-high performance concrete can be subjected to force as a whole with the reinforcing bar skeleton. The use of the stud, a shear-resistant connector, and the double mechanical interlocking effect of the reinforcing bar connecting rod ensures reliable force transmission between the H-shaped steel and the ultra-high performance concrete layer.

[0017] 2) This invention combines ultra-high performance concrete (UHPC) with H-shaped steel columns, fully leveraging the tensile strength of steel and the compressive strength of UHPC to form a synergistic working mechanism. The column's load-bearing capacity is significantly improved compared to a pure H-shaped steel column. Enhanced bending stiffness: The steel reinforcement skeleton forms a spatial truss structure, which, combined with shear studs, effectively restrains the core steel, improving overall bending stiffness and stability. Superior ductility and seismic performance: After embedding the steel reinforcement skeleton, UHPC is poured. Once formed, fiber-reinforced composite materials are used to wrap and tightly connect the two. The high toughness of UHPC and the restraining effect of the fiber-reinforced composite materials combine to give the component excellent deformation and energy dissipation capabilities, meeting the seismic requirements of high-intensity earthquake zones.

[0018] 3) The ultra-high performance concrete of the present invention has extremely low permeability and high resistance to chloride ion erosion, effectively isolating corrosive media and protecting the internal H-beam core; the outer fiber-reinforced composite material winding layer provides additional waterproof, anti-corrosion and UV protection, forming a multi-protection system to improve overall durability and protection. Attached Figure Description

[0019] Figure 1 This is a flowchart of the overall construction method for the device. Figure 2 This is a schematic diagram of an H-shaped steel column structure; Figure 3This is a schematic diagram of a combined structure of steel reinforcement cage and H-shaped steel columns; Figure 4 This is a schematic diagram of the overall structure of the device; Figure 5 This is an exploded view of the overall structure of the device.

[0020] Explanation of reference numerals in the attached drawings: 1. H-shaped steel column; 2. Steel tie rod; 3. Longitudinal steel bar; 4. Stud; 5. Ultra-high performance concrete; 6. Fiber-reinforced composite material. Detailed Implementation

[0021] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0022] Example 1 As one embodiment, a construction method for a composite reinforcement structure for H-shaped steel columns in in-service factory buildings is proposed, such as... Figure 1-5 As shown, it includes the following steps: S1, H-shaped steel column 1 surface cleaning; specifically, remove rust, oil and impurities from the web and flange surfaces of the H-shaped steel column 1 until the metal luster is exposed. By removing surface contaminants and oxide layers, the mechanical bonding force and adhesion strength between the subsequent interface agent and the steel are improved, ensuring a reliable connection between the reinforcement layer and the substrate. S2. Fabrication of the combined structure of the reinforcing steel cage and H-beam steel column 1: Bend both ends of the reinforcing steel connecting rod 2 and create a groove in the middle section; weld studs 4 to the web surface of the H-beam steel column 1, and place the reinforcing steel connecting rod 2 on the studs 4, securing the groove and the studs 4; weld both ends of the reinforcing steel connecting rod 2 to the flange surface of the H-beam steel column 1; weld longitudinal reinforcing bars 3 between the reinforcing steel connecting rods 2 to form a reinforcing steel cage; specifically, as follows... Figure 3 As shown, the studs 4 are evenly distributed along the height direction of the H-shaped steel column 1. The studs 4 are perpendicular to the web of the H-shaped steel column 1 and parallel to the flange of the H-shaped steel column 1. They are used to form shear-resistant connectors to withstand the horizontal shear force between the steel reinforcement cage and the concrete interface, prevent relative slippage between the two, and ensure the overall coordinated operation of the composite structure. The studs 4 can also be arranged in a quincunx or rectangular pattern. By optimizing the shear force transmission path through spacing and arrangement, stress concentration can be avoided, and connection efficiency and reliability can be improved. Prepare a steel bar connecting rod 2, which has bent sections at both ends and a straight section in the middle; the bent sections are easy to weld and fix to the flange of the H-shaped steel column 1, and the straight section is used to support the longitudinal steel bars 3 to form a spatial truss structure, providing lateral constraints and longitudinal reinforcement; The bent sections at both ends of the steel bar connector 2 are symmetrically welded to the flange surfaces on both sides of the H-beam 1, and the weld appearance is inspected. The symmetrical arrangement ensures that the load is evenly distributed and avoids eccentric force. The appearance inspection can detect welding defects in time and ensure the reliability of the connection. The longitudinal reinforcement 3 is directly welded to the reinforcement connecting rod 2. The longitudinal reinforcement 3 is parallel to the web and flange of the H-beam 1, close to the reinforcement connecting rod 2 and perpendicular to the reinforcement connecting rod 2, forming a combined structure of reinforcement skeleton and H-beam 1. The longitudinal reinforcement 3 and the reinforcement connecting rod 2 form a grid-like skeleton, which constrains the deformation of the five layers of ultra-high performance concrete, prevents concrete cracking and spalling, and improves the longitudinal bearing capacity of the component. The steel bar connecting rod 2 is made of HRB400 or HRB500 grade hot-rolled ribbed steel bar. The high-strength ribbed steel bar provides sufficient yield strength and surface interlocking effect. The diameter and length range ensures that the skeleton stiffness is moderate, which can effectively restrain the ultra-high performance concrete 5 and facilitate construction operation. The length coefficient ensures that the protective layer thickness is uniform. The longitudinal reinforcement 3 is made of HRB400 or HRB500 hot-rolled ribbed steel bars. The longitudinal reinforcement 3 bears part of the longitudinal load and restrains concrete shrinkage. The symmetrical arrangement ensures balanced stress. The quantity and spacing range can adapt to different column cross-section sizes and load levels to prevent longitudinal cracks from developing. The reinforcing bar 2 and the longitudinal reinforcing bar 3 can be made of ribbed steel bars of the same specification, which reduces costs; S3. Ultra-high performance concrete 5 spraying: Ultra-high performance concrete 5 is sprayed in layers between the flanges and web of the H-shaped steel column 1; specifically, as follows Figure 4 and Figure 5 As shown, five layers of ultra-high performance concrete (UHPC) are sprayed onto the exterior of the combined structure of the steel reinforcement cage and H-shaped steel column 1 to form a partial outer structure; the amount of UHPC 5 is reduced while ensuring performance, thereby reducing the structural self-weight and material costs; the compressive strength of the UHPC 5 is not less than 120 MPa and the tensile strength is not less than 8 MPa, ensuring the load-bearing capacity requirements through high strength; the UHPC 5 is UHPC. S31. Base treatment: Remove the loose and weak ultra-high performance concrete 5 and rinse the ultra-high performance concrete 5; by removing the weak layer, cleaning the surface and wetting it, the water absorption of the base can be reduced, and the rapid water loss of the ultra-high performance concrete 5 can be avoided to affect the hydration reaction and ensure the quality of interlayer bonding. S32. Shotcrete Construction: Apply ultra-high performance concrete 5 in layers, with the interval between layers controlled before the initial setting of the current layer of ultra-high performance concrete 5; repeat steps S31 and S32 until the ultra-high performance concrete 5 encapsulates the reinforcing steel skeleton; specifically, spray ultra-high performance concrete 5 in 2-3 layers, with the interval between layers controlled before initial setting to ensure tight bonding between layers, and the total thickness is set according to structural requirements; control the release of hydration heat through layered spraying to prevent temperature cracks; the layers bond together to form a whole before initial setting, ensuring density and uniformity, and adapting to different reinforcement thickness requirements. S33. Curing treatment: After the ultra-high performance concrete 5 is sprayed, cover it with a moisture-retaining curing agent to keep the surface of the ultra-high performance concrete 5 moist, ensure that the cement is fully hydrated, develop high strength and high toughness, prevent early drying shrinkage cracking, and ensure long-term performance. Before S3, the process also includes: applying an interface agent to the inner surface of the flange and the web surface of the H-beam steel column 1. The interface agent is epoxy or cement-based penetrating crystalline type, with a coating thickness of 0.5-1.0 mm, to enhance the bonding performance between the H-beam steel 1 and the ultra-high performance concrete 5; by filling the micro-unevenness of the steel, the interface bonding strength is improved, and the intrusion of corrosive media is blocked. Epoxy-based agents are suitable for dry environments, while penetrating crystalline types are suitable for humid environments. The thickness range ensures uniform coverage and prevents dripping. S4, Fiber Reinforced Composite Material 6 Encapsulation Protective Layer Construction: (e.g.) Figure 4 and Figure 5 As shown, the H-shaped steel column 1 is wrapped with fiber-reinforced composite material 6, forming an encapsulated protective layer that provides passive constraint pressure, restricts the lateral expansion of the ultra-high performance concrete 5, and improves its compressive strength and ductility. The overlap width ensures fiber continuity and overall stress performance, forming a sealed protective layer. The fiber-reinforced composite material 6 is FRP, which can be carbon fiber reinforced composite material, glass fiber reinforced composite material, or basalt fiber reinforced composite material. Multiple fiber types are suitable for different environments. The materials are adjusted according to general atmospheric environment, coastal corrosion environment, and chemical corrosion environment. The unit area mass and number of layers ensure moderate constraint stress, providing effective circumferential constraint while avoiding brittle failure due to excessive reinforcement. The use of HRB400 or HRB500 grade hot-rolled ribbed steel bars, ultra-high performance concrete 5 with a compressive strength ≥120MPa, and high-strength fiber-reinforced composite material 6 achieves a balance between high performance and material conservation. S4 is followed by: applying a weather-resistant protective coating to the outer surface of the protective layer of the fiber-reinforced composite material 6; the coating is a polyurethane or fluorocarbon coating, which can isolate ultraviolet rays, moisture and oxygen, and prevent the fiber-reinforced composite material 6 from aging and degradation and interfacial adhesion degradation. Polyurethane is suitable for general environments, while fluorocarbon is suitable for harsh environments. The thickness ensures protective durability and extends the service life of the structure.

[0023] Example 2 As another embodiment, this second embodiment, based on the first embodiment, proposes another construction method for a composite reinforcement structure of H-shaped steel columns in in-service factory buildings, such as... Figure 1-5 As shown, it includes the following steps: S1, H-shaped steel column 1 surface cleaning; S2. Fabrication of the combined structure of the reinforcing steel frame and H-shaped steel column 1: Bend both ends of the reinforcing steel link 2 and set a groove in the middle section; weld studs 4 to the web surface of the H-shaped steel column 1, and place the reinforcing steel link 2 on the studs 4 to secure the groove and the studs 4; weld both ends of the reinforcing steel link 2 to the flange surface of the H-shaped steel column 1; weld longitudinal steel bars 3 between the reinforcing steel link 2 to form a reinforcing steel frame; S3. Ultra-high performance concrete 5 spraying: Ultra-high performance concrete 5 is sprayed in layers between the flange and web of the H-shaped steel column 1; specifically, ultra-high performance concrete 5 is sprayed in the space formed by the interlocking steel plates surrounding the H-shaped steel column 1 and the space enclosed by the interlocking steel plates and the H-shaped steel column 1. The interlocking steel plates are U-shaped, and the two sides of the interlocking steel plates are provided with bent sections with bolt holes. The bent sections bend outwards, and the bent sections of the two interlocking steel plates are attached to each other and fixed with bolts to prevent leakage of ultra-high performance concrete 5; the modular design realizes factory prefabrication and rapid on-site assembly, shortening the construction period; S4. Construction of the protective layer of fiber-reinforced composite material 6: Wrap the H-shaped steel column 1 with fiber-reinforced composite material 6; specifically, the steel pipe does not need to be disassembled, and the fiber-reinforced composite material 6 is wrapped around the outside of the steel pipe.

[0024] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0025] Example 3 As another embodiment, this third embodiment proposes, based on the second embodiment, a composite reinforcement structure for H-shaped steel columns in in-service factory buildings, such as... Figure 1-5As shown, the structure includes an H-shaped steel column 1, a reinforcing steel frame, ultra-high performance concrete 5, and fiber-reinforced composite material 6. The web of the H-shaped steel column 1 is welded with studs 4. The reinforcing steel frame includes reinforcing bar 2 and longitudinal reinforcing bars 3. The two ends of the reinforcing bar 2 are bent sections, and the middle section is a straight section with grooves. The reinforcing bar 2 is secured to the studs 4 through the grooves and the studs 4. The bent sections at both ends of the reinforcing bar 2 are symmetrically welded to the flanges on both sides of the H-shaped steel column 1, and the longitudinal reinforcing bars 3 are welded between the straight sections of the reinforcing bar 2. The ultra-high performance concrete 5 is poured between the web and flanges of the H-shaped steel column 1. The fiber-reinforced composite material 6 covers the H-shaped steel column 1, forming a multi-layered synergistic system of steel-concrete-composite materials. Each layer has a clear and complementary function, achieving a comprehensive improvement in load-bearing capacity, ductility, and durability, suitable for both new construction reinforcement and existing reinforcement. Specifically, such as Figure 3 As shown, the steel reinforcement skeleton is formed by welding steel reinforcement rods 2 and longitudinal steel bars 3 to form a spatial truss structure. The bent section of the steel reinforcement rod 2 is welded to the flange of the H-beam 1 to form lateral restraint, and the longitudinal steel bars 3 are welded to the straight section of the steel reinforcement rod 2 to form longitudinal stiffeners. The spatial truss structure provides a three-dimensional restraint effect, suppressing local buckling of the core steel and lateral deformation of the five layers of ultra-high performance concrete. The bent section is reliably anchored, and the longitudinal steel bars 3 are continuously connected, which together improve the overall stability and deformation capacity of the component. The ultra-high performance concrete cladding layer 5 covers the outer surface of the flange and both sides of the web of the H-shaped steel column 1, while the inner surface of the flange of the H-shaped steel column 1 is exposed or partially wrapped. The thickness range adapts to different load and protection requirements, covering the main stress area to improve load-bearing capacity and durability. Exposing the inner surface of the flange saves materials, reduces self-weight, and facilitates on-site connection, achieving an optimal balance between performance and economy.

[0026] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 2 can be referred to each other, and will not be repeated in this application.

[0027] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

Claims

1. A construction method for a composite reinforcement structure for H-shaped steel columns in in-service factory buildings, characterized in that, Includes the following steps: S1, H-shaped steel column (1) Surface cleaning; S2. Construction of the combined structure of steel reinforcement cage and H-shaped steel column (1): Bend both ends of the steel reinforcement rod (2) and set a groove in the middle section; weld studs (4) on the web surface of the H-shaped steel column (1), and place the steel reinforcement rod (2) on the studs (4) to secure the groove and the studs (4); weld both ends of the steel reinforcement rod (2) to the flange surface of the H-shaped steel column (1); weld longitudinal steel bars (3) between the steel reinforcement rods (2) to form a steel reinforcement cage; S3, Ultra-high performance concrete (5) spraying: Ultra-high performance concrete (5) is sprayed in layers between the flange and web of the H-shaped steel column (1). S4. Construction of the protective layer of fiber reinforced composite material (6): Wrap the H-shaped steel column (1) with fiber reinforced composite material (6).

2. The construction method for the composite reinforcement structure for H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, In step S2, the studs (4) are evenly distributed along the height direction of the H-shaped steel column (1), and the studs (4) are perpendicular to the web of the H-shaped steel column (1) and parallel to the flange of the H-shaped steel column (1).

3. The construction method for the composite reinforcement structure of H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, In step S2, the two ends of the steel bar connecting rod (2) are bent sections, and the middle part of the steel bar connecting rod (2) is a straight section; the bent sections at both ends of the steel bar connecting rod (2) are symmetrically welded to the flange surfaces on both sides of the H-shaped steel column (1); the longitudinal steel bar (3) is welded between the straight sections of the steel bar connecting rod (2), and the longitudinal steel bar (3) is parallel to the web and flange of the H-shaped steel column (1) and perpendicular to the straight sections of the steel bar connecting rod (2).

4. The construction method for the composite reinforcement structure for H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, In step S2, both the steel bar connecting rod (2) and the longitudinal steel bar (3) are ribbed steel bars.

5. The construction method for the composite reinforcement structure for H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, Step S3 also includes the following steps: S31. Base treatment: Remove the loose and weak ultra-high performance concrete (5) and rinse the ultra-high performance concrete (5). S32, Shotcrete construction: Shotcrete ultra-high performance concrete (5) in layers, with the interval between layers controlled before the initial setting of the current ultra-high performance concrete (5) layer; repeat steps S31 and S32 until the ultra-high performance concrete (5) wraps the steel reinforcement skeleton. S33. Curing treatment: After the ultra-high performance concrete (5) is sprayed, cover it for moisturizing and curing.

6. The construction method for the composite reinforcement structure of H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, In step S3, ultra-high performance concrete (5) is sprayed and poured in the space formed by the spliced ​​steel plates surrounding the H-shaped steel column (1).

7. The construction method for the composite reinforcement structure for H-shaped steel columns in in-service factory buildings according to claim 6, characterized in that, In step S3, the spliced ​​steel plates are U-shaped, and the two sides of the spliced ​​steel plates are provided with bent sections with bolt holes. The bent sections of the two spliced ​​steel plates are attached to each other and fixed by bolts.

8. The construction method for the composite reinforcement structure for H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, Before step S3, an interface agent is applied to the inner surface of the flange and the web surface of the H-shaped steel column (1).

9. The construction method for the composite reinforcement structure for H-shaped steel columns in in-service factory buildings according to claim 1, characterized in that, Step S4 is followed by applying a weather-resistant protective coating to the outer surface of the fiber-reinforced composite material (6) encapsulation protective layer.

10. A composite reinforcement structure for H-shaped steel columns in in-service factory buildings, manufactured by the construction method described in any one of claims 1-9, characterized in that, The structure includes an H-shaped steel column (1), a reinforcing cage, ultra-high performance concrete (5), and fiber-reinforced composite material (6); the web of the H-shaped steel column (1) is welded with studs (4); the reinforcing cage includes reinforcing bar connecting rods (2) and longitudinal reinforcing bars (3); the ends of the reinforcing bar connecting rods (2) are bent sections, and the middle is a straight section with a groove; the reinforcing bar connecting rods (2) are secured to the studs (4) by the grooves and the studs (4); the bent sections at both ends of the reinforcing bar connecting rods (2) are symmetrically welded to the flanges on both sides of the H-shaped steel column (1), and the longitudinal reinforcing bars (3) are welded between the straight sections of the reinforcing bar connecting rods (2); the ultra-high performance concrete (5) is poured between the web and flanges of the H-shaped steel column (1); and the fiber-reinforced composite material (6) covers the H-shaped steel column (1).

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