Hollow steel reinforced concrete beam and connecting joint thereof with a cable

Abstract

The application discloses a hollow steel reinforced concrete beam and a connecting joint thereof with a cable, and belongs to the technical field of building structure engineering. The joint comprises the following parts: a hollow thin-wall steel provided with studs, concrete casted outside the hollow thin-wall steel, flange plates welded at the end of the hollow thin-wall steel, first fasteners arranged between the flange plates and the concrete, cable connecting lug plates arranged between two flange plates at the end of two adjacent beams, second fasteners sequentially penetrating through the first flange plate, the lug plate and the second flange plate, and a pin shaft penetrating through the cable connecting hole of the lug plate and the end of the cable. The hollow thin-wall steel reinforced concrete structure is adopted to reduce the dead weight, and the external concrete coating solves the problem of steel corrosion; the flange splicing type joint does not need to be welded and cast in situ on site; the cable pin shaft type connection is convenient to disassemble and can quickly replace the cable or overhaul the joint. The application is suitable for the boundary constraint component of a marine flexible photovoltaic system and other engineering structures which need to be regularly maintained and modularly assembled.

Description

Technical Field

[0001] This invention relates to the field of building structure engineering technology, and in particular to a connection technology between a steel-concrete composite beam and cables, specifically a hollow steel-concrete beam and its connection node with cables. Background Technology

[0002] Flexible photovoltaic technology has been widely used in onshore photovoltaic fields due to its advantages of being lightweight, flexible, and easy to install. In recent years, as photovoltaic development has expanded to the ocean, offshore flexible photovoltaic systems are facing a series of new technical challenges.

[0003] When flexible photovoltaic systems are used in marine environments, their boundary constraint components need to address the following issues simultaneously: if a pure steel structure is used, the steel will corrode severely in the high salt spray and high humidity environment of the ocean, resulting in extremely high maintenance costs; if a pure concrete structure is used, the self-weight of the components will increase significantly, which will not only be detrimental to marine transportation and hoisting operations, but also place greater load demands on the underlying foundation structure.

[0004] While some existing technologies propose using solid steel-concrete composite components to replace pure steel or pure concrete components, the self-weight of solid components remains relatively large, failing to fully leverage the advantages of lightweight design. Furthermore, the connection nodes between traditional flexible photovoltaic cables and rigid components (such as ear plate nodes, steel anchor box nodes, and cross-shaped node plate nodes) often employ on-site welding. However, harsh offshore construction conditions make it difficult to guarantee welding quality, and the nodes are not removable, causing significant inconvenience for later inspection and maintenance.

[0005] Therefore, there is an urgent need for a boundary constraint component and its connection node with the cable that is both corrosion resistant and significantly lightweight, and can be assembled for construction and easy to maintain. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a hollow steel-concrete composite beam and its connection node with the cable, aiming to solve the technical problems of easy corrosion of steel components, heavy self-weight of concrete components, inability to assemble traditional connection nodes for construction and difficulty in maintenance in offshore flexible photovoltaic systems.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a hollow steel-concrete composite beam and its connection node with cables, comprising: Hollow steel section, wherein a number of studs are fixedly provided on the outer wall of the hollow steel section; Concrete is poured and poured to cover the outside of the hollow steel section to form a hollow steel-concrete beam; The flange plate is directly welded to the end of the hollow steel section, and a first fastener is provided between the flange plate and the concrete. The first fastener is used to strengthen the connection between the flange plate and the concrete. The cable-connecting lugs are located between two flange plates at the ends of two adjacent hollow steel-concrete beam sections; The second fastener passes through the first flange plate, the cable connecting lug plate, and the second flange plate in sequence to fasten the three together. The cable connecting lug plate has a cable connecting hole, and a pin passes through the cable connecting hole. The pin also passes through the end of the cable to connect the cable to the cable connecting lug plate.

[0008] Furthermore, the first fastener is one or more combinations of anchor bars, shear keys, or studs, with one end connected to the flange plate and the other end anchored inside the concrete. The first fastener is an auxiliary structure that strengthens the connection between the flange plate and the concrete, and can be selected or omitted depending on the stress requirements.

[0009] Furthermore, the second fastener is a high-strength bolt, and the cable connecting lug is clamped between the two flange plates and fixed by the second fastener.

[0010] Furthermore, the hollow steel section has a cross-sectional shape that is circular, square, or polygonal; and the hollow steel section is made of Q355 or Q390 steel.

[0011] Furthermore, the concrete is high-strength concrete with a strength grade of not less than C40.

[0012] Furthermore, the stud is a cylindrical head weld stud, welded to the outer wall of the hollow steel section.

[0013] Furthermore, the flange plate is one of a necked welding flange, a slip-on flange, or a socket welding flange.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. Significantly reduces the self-weight of components and lowers construction difficulty: By using hollow steel sections and encasing them in concrete, the self-weight can be reduced compared to solid steel-concrete beams, effectively reducing the cost of marine transportation and hoisting; at the same time, the hollow design reduces the amount of concrete used, thus lowering material costs.

[0016] 2. Excellent corrosion resistance: The hollow steel sections are completely encased in external concrete, isolating the steel from direct contact with seawater and significantly extending the service life of the components. The concrete itself has good durability in marine environments, further enhancing the overall structure's corrosion resistance. Furthermore, only the steel components in the joint areas require anti-corrosion treatment, greatly reducing the amount of anti-corrosion materials and coating work required for the overall structure.

[0017] 3. Achieve fully prefabricated construction: The welding of flange plates and hollow steel sections is completed in the factory; on site, only the flange plates and intermediate ear plates of the two beam sections need to be passed through and fastened at one time with the second fastener, without the need for on-site welding or cast-in-place work.

[0018] 4. Convenient cable replacement: When replacing cables, simply pull out the pin to separate the old cable, insert the new cable, and reinsert the pin to complete the fixation. There is no need to remove the second fastener, and the two beams remain continuous, greatly reducing the difficulty of operation and maintenance.

[0019] 5. Factory prefabrication and quality control: All components can be completed in the factory, which helps to ensure processing accuracy and welding quality, and only assembly is required on site. Attached Figure Description

[0020] Figure 1 This is an axonometric view of a hollow steel-concrete composite member according to an embodiment of the present invention; Figure 2 Axonometric view of a hollow steel-concrete composite member with flanges; Figure 3 This is an isometric view of the flange splicing connection node of the present invention; Figure 4 This is a top view of the flange splicing connection node of the present invention; Figure 5 This is a front view schematic diagram of the flange splicing connection node of the present invention; Figure 6 This is a cross-sectional view of the flange splicing connection node of the present invention; Figure 7 This is an isometric view of the flange splicing connection node (without concrete) of the present invention; Figure 8 This is a front view schematic diagram of the flange splicing connection node (without concrete) of the present invention.

[0021] Explanation of reference numerals in the attached drawings: 1. Stud; 1-1. First fastener; 1-2. Second fastener; 2. Concrete; 3. Hollow steel section; 4. Cable connection lug; 5. Hollow steel-concrete beam; 6. Cable connection hole; 7. Flange plate. Detailed Implementation

[0022] The following is in conjunction with the appendix Figures 1 to 8 The present invention provides a detailed description of a hollow steel-concrete composite beam and its connection node with cables.

[0023] like Figures 1 to 2As shown, this embodiment provides a hollow steel-concrete beam 5, which is constructed as follows: First, a number of studs 1 are welded to the outer surface of the hollow steel 3 at predetermined intervals; then, a formwork is erected on the outside of the hollow steel 3 and high-strength concrete 2 is poured to form the hollow steel-concrete beam 5. The hollow steel 3 is a circular steel pipe made of Q355 steel, the concrete 2 is C40 high-strength concrete, and the studs 1 are cylindrical head weld studs.

[0024] The flange plate 7 is directly welded to the end of the hollow steel section 3. In this embodiment, the flange plate 7 is a flat-welded flange, and a first fastener 1-1 is provided between the flange plate 7 and the concrete 2. In this embodiment, the first fastener 1-1 is a weld stud, with one end welded to the back of the flange plate 7 and the other end anchored inside the concrete 2. Several studs are evenly arranged around the perimeter of the flange plate. The first fastener 1-1 is used to strengthen the connection between the flange plate 7 and the concrete 2, transfer part of the tensile force borne by the flange plate to the concrete, and reduce the stress concentration at the welded joint between the flange plate and the hollow steel section.

[0025] like Figures 3 to 6 As shown, this embodiment provides a flange splicing connection node for connecting two hollow steel-concrete beams 5 and connecting flexible photovoltaic cables.

[0026] The specific connection method is as follows: The flange plates 7 at the ends of the two hollow steel-concrete beams 5 are placed opposite each other, with a gap reserved in the middle for placing the cable connection lugs 4. Place the cable connecting lug 4 in the gap between the two flange plates 7 and align the bolt holes; Pass the second fasteners 1-2 through the left flange plate 7, the cable connecting ear plate 4, and the right flange plate 7 in sequence, and tighten the nuts to secure the three together. The cable connection lug 4 has a cable connection hole 6 pre-set on it. The cable end is provided with a connector. After aligning the connector at the cable end with the lug of the cable connection lug 4, the pin is inserted into the cable connection hole 6 and simultaneously passes through the connector at the cable end to complete the connection between the cable and the beam.

[0027] The second fastener 1-2 uses a high-strength bolt (grade 10.9, specification M24), along with a lock nut and a flat washer. The second fastener 1-2 passes through the two flange plates 7 and the middle cable connecting lug 4, and is the only fastener that secures the three together.

[0028] The procedure for replacing the cable is as follows: When it is necessary to replace the cable, simply pull the pin out of the cable connection hole 6 to separate the end of the old cable from the cable connection lug 4 and remove the old cable; then place the connector of the new cable end at the lug of the cable connection lug 4, and reinsert the pin to complete the cable replacement. The entire process does not require disassembling the second fastener 1-2, and the two beam sections and the cable connection lug remain continuously fixed, eliminating the need to readjust the beam alignment.

[0029] like Figures 7 to 8 As shown, to more clearly illustrate the assembly relationship of the metal components, this embodiment demonstrates the connection node structure in the state before concrete pouring. It can be seen that the hollow steel section 3, flange plate 7, cable connection lug plate 4, first fastener 1-1, second fastener 1-2, and stud 1 are all prefabricated components in the factory, requiring only on-site assembly according to the design drawings.

[0030] It should be noted that the first fastener 1-1 is one or more combinations of anchor bars, shear keys, or studs, used to strengthen the connection between the flange plate and the concrete, and can be selected or omitted according to the stress requirements. The second fastener 1-2 uses high-strength bolts, and grade 10.9 or 8.8 can be selected according to the design load requirements. In marine environments, the surface of the fasteners should be hot-dip galvanized or otherwise treated for corrosion protection. Stud 1 is a cylindrical head weld stud, welded to the outer wall of the hollow steel section 3, used to enhance the bond strength and shear resistance between the concrete 2 and the hollow steel section 3.

[0031] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A hollow steel-concrete composite beam and its connection node with cables, characterized in that, include: Hollow steel section, wherein a number of studs are fixedly provided on the outer wall of the hollow steel section; Concrete is poured and poured to cover the outside of the hollow steel section to form a hollow steel-concrete beam; The flange plate is directly welded to the end of the hollow steel section, and a first fastener is provided between the flange plate and the concrete. The first fastener is used to strengthen the connection between the flange plate and the concrete. The cable-connecting lugs are located between two flange plates at the ends of two adjacent hollow steel-concrete beam sections; The second fastener passes through the first flange plate, the cable connecting lug plate, and the second flange plate in sequence to fasten the three together. The cable connecting lug plate has a cable connecting hole, and a pin passes through the cable connecting hole. The pin also passes through the end of the cable to connect the cable to the cable connecting lug plate.

2. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, The first fastener is one or more combinations of anchor bars, shear keys, or studs, with one end connected to the flange plate and the other end anchored inside the concrete.

3. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, The second fastener is a high-strength bolt, and the cable connecting lug is clamped between two flange plates and fixed by the second fastener.

4. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, When replacing the cable, simply pull out the pin to separate the old cable from the cable connecting lug, insert the new cable, and then reinsert the pin to complete the fixation.

5. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, The hollow steel section has a cross-sectional shape that is circular, square, or polygonal; the hollow steel section is made of Q355 or Q390 steel.

6. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, The concrete is high-strength concrete with a strength grade of not less than C40.

7. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, The stud is a cylindrical head weld stud, which is welded to the outer wall of the hollow steel section.

8. The hollow steel-concrete composite beam and its connection node with the cable according to claim 1, characterized in that, The flange is one of a necked welding flange, a slip-on flange, or a socket welding flange.

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