A concrete beam-column structure with local inner arrangement of thin-walled steel pipes and a method for installing the same

Abstract

The present application belongs to the technical field of concrete beam-column structure, and specifically relates to a beam-column structure with locally internally arranged thin-walled steel pipes and a mounting method thereof. By reasonably arranging the internally arranged steel pipes and steel bars, the effects of reducing the self weight and improving the bearing capacity of the structure are achieved. The application of the steel pipes not only enhances the bending and shearing resistance of the concrete components, but also effectively delays the generation and expansion of cracks. In addition, due to the high strength and rigidity of the steel pipes, the structure can still remain stable under high load conditions, and is particularly suitable for occasions requiring high bearing capacity, such as bridges and buildings. A new design method of internally arranged steel pipe concrete is proposed by fully considering the stress characteristics of the beam-column components. Through detailed analysis of the structural details and working principles, professional technicians can implement the present application according to the description, so as to effectively improve the safety and economy of the engineering structure. The present application is used for improving the shearing, bending and overall stability of the structure.

Description

Technical Field

[0001] This invention belongs to the field of concrete beam-column structure technology, specifically relating to a concrete beam-column structure with locally internal thin-walled steel pipes and its installation method. Background Technology

[0002] Since its inception, reinforced concrete structures have undergone numerous innovations, gradually evolving into various new structural forms, such as composite structures like internally reinforced steel-concrete structures and externally encased thin-walled steel tube concrete structures, as well as box-type structures such as box girders and hollow columns. The emergence of these new structures has brought new development opportunities to traditional concrete structures. This paper studies a locally internally reinforced thin-walled steel tube concrete structure, an innovative form aimed at improving overall performance and economy through structural design improvements. Currently, domestic and international scholars have conducted preliminary research on the load-bearing capacity of internally reinforced thin-walled steel tube concrete beams, but the research is still in its early stages. Research mainly focuses on flexural load-bearing capacity, with results showing that internally reinforced thin-walled steel tube concrete beams have high ductility. The thickness of the thin-walled steel tube, the longitudinal reinforcement ratio, and whether or not concrete is used to fill the interior significantly affect the beam's flexural performance. For example, Cai Jian conducted flexural tests on multiple internally reinforced thin-walled steel tube concrete beams and established corresponding calculation methods. Xie Hengyan's research further demonstrates that internally reinforced thin-walled steel tube concrete beams not only have strong deformation capacity but also relatively high flexural stiffness. However, research on the shear performance of this type of beam has not yet been conducted, and the calculation methods and design theories for shear bearing capacity are still lacking. Compared with beam research, research on the bearing capacity of columns with internal thin-walled steel tubes is even scarcer, with almost no relevant experimental data and theoretical results. However, reinforced concrete hollow piers with similar structural characteristics have been widely used in bridge engineering, and their research results can provide a reference for this project. Related studies have shown that box-section columns have larger moments of inertia and torsional stiffness. Compared with solid columns of the same volume, box-section columns have significantly improved ultimate bearing capacity, ductility, and energy dissipation capacity. In addition, research on some precast assembled steel-concrete composite columns shows that the bearing capacity and stiffness of solid columns are generally higher than those of hollow columns, especially under large eccentric loading, where the bending stiffness of hollow columns is significantly lower. These results provide a reference for the design of columns with internal thin-walled steel tubes, but more experiments are still needed to improve the bearing capacity calculation methods. Summary of the Invention

[0003] This invention provides a beam-column structure with locally internal thin-walled steel pipes and its installation method, in order to solve the technical problems existing in the prior art, such as the inability to accurately locate the defect position inside the thin-walled steel pipe, the need to manually mark the defect, and the inability to mark the high-level defect inside the thin-walled steel pipe.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A concrete beam-column structure with locally internally fitted thin-walled steel pipes is provided. Thin-walled steel pipes are set in the core position of the beams and columns. End flanges are installed at both ends of the thin-walled steel pipes. Connecting reinforcing bars are welded on the end flanges. Reinforcing bars are set on the thin-walled steel pipes and pass through the end flanges at both ends of the thin-walled steel pipes.

[0006] Thin-walled steel pipes are manufactured using high-frequency plate rolling and welding technology, and the material is Q355 steel.

[0007] A filler inlet pipe is installed at one end of the thin-walled steel pipe and an overflow pipe is installed at the other end.

[0008] Concrete is poured around the outer periphery of the thin-walled steel pipe, and studs are installed around the outer periphery of the thin-walled steel pipe to tightly connect the thin-walled steel pipe to the surrounding concrete.

[0009] The studs on the thin-walled steel pipe are evenly distributed along the length of the thin-walled steel pipe. The length of the studs is 6cm and the diameter of the studs is not less than 1cm.

[0010] The reinforcing bars are placed at the top and bottom of the thin-walled steel pipe.

[0011] The end wing rings at both ends of the thin-walled steel pipe have openings at the positions of the reinforcing bars at the upper and lower ends. Wire mesh is welded and fixed to the end wing rings. The reinforcing bars at the upper and lower parts of the thin-walled steel pipe pass through the wire mesh through the circular openings to the end wing rings.

[0012] The outer sides of the reinforcing bars at the top and bottom of the thin-walled steel pipe are fixed by several stirrups.

[0013] The connection between the reinforcing bars is achieved by extruding the reinforcing bar sleeves.

[0014] A design method for a concrete beam-column structure with locally internally fitted thin-walled steel pipes involves installing end flanges at both ends of the thin-walled steel pipes, extending connecting reinforcing bars outward by welding to the outer side of the end flanges at both ends of the thin-walled steel pipes, and setting reinforcing bars at the upper and lower parts of the thin-walled steel pipes to connect and fix the beams and columns at the connection nodes.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] This invention discloses a concrete beam-column structure with locally internally reinforced thin-walled steel pipes. By installing end flanges at both ends of the thin-walled steel pipes and welding reinforcing bars, the overall stability and load-bearing capacity of the structure are enhanced. Simultaneously, the design of the reinforcing bars passing through the end flanges makes the connection between the reinforcing bars and the steel pipes more robust, reducing positioning deviations caused by weak connections.

[0017] Furthermore, the high-frequency coil welding process improves the manufacturing precision of steel pipes and reduces welding defects, thereby lowering the possibility of internal defects in the steel pipes. Q355 steel has high strength and toughness, enabling it to better resist external stress and reduce defects caused by insufficient material properties.

[0018] Furthermore, the design of the filler inlet pipe and overflow pipe facilitates the injection of testing media or filler material into the steel pipe, enabling non-destructive testing (such as ultrasonic testing) and thus accurately locating defects within the steel pipe. Simultaneously, these pipes can also be used to remove excess material, avoiding testing errors caused by uneven filling.

[0019] Furthermore, using studs to secure the connection between the steel pipe and the concrete increases the friction and bonding force between them, ensuring a tight bond and reducing defects caused by relative slippage. In addition, this design allows for indirect assessment of the internal condition of the steel pipe by observing changes in the concrete surface.

[0020] Furthermore, the evenly distributed studs around the thin-walled steel pipe provide a more stable connection, reducing local stress concentration and lowering the risk of defects caused by stress concentration. At the same time, the specific dimensions of the studs ensure sufficient connection strength, further improving the structural safety.

[0021] Furthermore, larger diameter steel bars improve the overall stiffness and load-bearing capacity of the structure, reducing defects caused by steel bar deformation. At the same time, the placement of the steel bars helps to distribute the load and reduce localized stress concentration.

[0022] Furthermore, the design of the wire mesh and circular openings ensures a precise connection between the reinforcing bars and the end flanges, reducing positioning deviations caused by weak connections. At the same time, the wire mesh provides additional support, enhancing the overall structural stability.

[0023] Furthermore, the use of stirrups strengthens the connection between the reinforcing bars and the steel pipe, reducing defects caused by the movement of the reinforcing bars. At the same time, the evenly distributed stirrups improve the overall stiffness and shear resistance of the structure.

[0024] Furthermore, the rebar sleeve extrusion connection is a reliable connection method that reduces the defects caused by traditional welding connections. This connection method not only improves the connection strength but also simplifies the construction process and reduces errors caused by manual operation.

[0025] Furthermore, this installation method integrates the characteristics of the aforementioned beam-column structure with locally integrated thin-walled steel pipes. Through optimizations in end flanges, connecting reinforcements, steel bars, and studs, it significantly improves the overall stability and load-bearing capacity of the structure. Simultaneously, these designs facilitate non-destructive testing, accurately locate defects, reduce the need for manual marking, and solve the problem of marking defects at high locations. Attached Figure Description

[0026] Figure 1 Schematic diagram of beam section;

[0027] Figure 2 : Schematic diagram of column section;

[0028] Figure 3 : Structural construction diagram;

[0029] Figure 4 : Schematic diagram of stirrup studs;

[0030] Figure 5 : Schematic diagram of steel pipe structure within beam-column structure;

[0031] Figure 6 Simplified diagram of steel pipes inside beam-column structure:

[0032] Figure 7 Perspective view of the beam after construction is complete;

[0033] Figure 8 Perspective view of the column after construction is completed;

[0034] Figure 9 Schematic diagram of the AA section of the uncast functional material steel pipe;

[0035] Figure 10 Schematic diagram of the BB section of the steel pipe;

[0036] Figure 11 Schematic diagram of the AA section of the steel pipe used for casting functional materials;

[0037] Figure 12 : Precast steel pipe components with completed concrete pouring;

[0038] Figure 13 : Schematic diagram of ESTRC1 and RC load-displacement curves;

[0039] Figure 14 : ESTRC1, RC load-deflection curve schematic diagram.

[0040] Labeling Explanation: 1. Thin-walled steel pipe; 2. Reinforcing bar; 3. Stirrup; 4. Stud; 5. End flange; 6. Connecting reinforcing bar; 7. Reinforcing bar sleeve; 8. Filler inlet pipe; 9. Overflow pipe; 10. Wire mesh. Detailed Implementation

[0041] To further understand the content of this invention, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments are merely illustrative and not limiting of the invention.

[0042] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0043] See Figures 1 to 12A concrete beam-column structure with thin-walled steel pipes embedded in certain areas, wherein thin-walled steel pipes 1 are installed in the core parts of both the beam and column structures, such as... Figure 1 , Figure 2 As shown in the figure, studs 4 are evenly arranged along the long side of the outer periphery of the thin-walled steel pipe 1. Several reinforcing bars 2 are set at the upper and lower parts of the thin-walled steel pipe 1, and the reinforcing bars 2 are placed longitudinally along the long side of the thin-walled steel pipe 1, as shown in the figure. Figure 3 As shown, the reinforcing bars 2 between beams and columns, between beams and beams, and between columns are fixed by reinforcing bar sleeves, as shown. Figure 7 and 8 As shown, wire mesh 10 is welded to the openings at both ends of the reinforcing bar 2, as... Figure 11 As shown in the figure, several stirrups 3 are evenly fixed around the outer periphery of the openings at both ends of the reinforcing bar 2, such as... Figure 4 As shown, the stirrups 3 are horizontally fixed to the outside of the reinforcing bar 2 along the direction of the reinforcing bar 2. End flanges 5 are welded to the outer periphery of the openings at both ends of the thin-walled steel pipe 1. The end flanges 5 have an annular plate structure, and connecting reinforcing ribs 6 are welded onto the end flanges 5. A filler inlet pipe 8 and an overflow pipe 9 are respectively provided at both ends on one side of the thin-walled steel pipe 1. Figure 7 and Figure 8 As shown; thin-walled steel pipe 1 is placed in beams and columns, and steel bars 2 are connected and assembled, then concrete is poured to form the structure. Figure 5 The structure shown; during concrete pouring, a certain space is left between the concrete and the end flanges at both ends of the steel pipe as a construction joint by using a pouring formwork. Figure 12 As shown in the image.

[0044] This embodiment provides a concrete beam-column structure with locally internally reinforced thin-walled steel tubes and its installation method, which is used to improve the shear and bending resistance and overall stability of the structure. The specimen is composed of thin-walled steel tubes, reinforcing bars, and concrete. By rationally configuring the thin-walled steel tubes 1 and reinforcing bars 2, the self-weight of the structure is reduced and the load-bearing capacity is improved. The specific implementation steps are as follows:

[0045] During installation, prefabricated steel pipe components need to be manufactured according to the actual design requirements of the beams and columns. In this embodiment, the beam cross-section is 300mm × 450mm, and the column cross-section is 450mm × 450mm. Based on the dimensions of the beams and columns, the required thin-walled steel pipe 1 is prepared. The thin-walled steel pipe 1 is manufactured using high-frequency plate rolling and welding technology and has undergone anti-corrosion treatment; the material is Q355 steel. A filler inlet pipe 8 and an overflow pipe 9 are installed at both ends of the outer side of the thin-walled steel pipe 1, respectively. Studs 4 are evenly arranged along the long side of the outer circumference of the thin-walled steel pipe 1, with a spacing of 200cm and a diameter of not less than 1cm. The length and spacing of the studs can be flexibly arranged according to design requirements to ensure… The thin-walled steel pipe 1 and the concrete work together; end wing rings 5 ​​are welded to the outer periphery of both ends of the thin-walled steel pipe 1. The end wing rings 5 ​​are ring-shaped plate structures. Openings are made on the end wing rings 5 ​​at the upper and lower ends of the thin-walled steel pipe 1. Wire mesh 10 is welded to the openings at both ends of the thin-walled steel pipe 1. The wire mesh 10 can prevent the concrete poured outside the steel pipe from flowing into the steel pipe. Compared with setting a solid plate structure at the opening of the thin-walled steel pipe 1, the self-weight of the structure is further reduced while achieving the same effect; connecting reinforcing ribs 6 extending outward are welded to the end wing rings 5 ​​on both sides of the steel pipe to strengthen the connection between the thin-walled steel pipe 1 and the concrete. In addition, the connecting reinforcing ribs 6 can also be welded to the inner wall of the thin-walled steel pipe 1.

[0046] The prefabricated steel pipe components are numbered and then transported to the processing site. Thin-walled steel pipes 1 are placed in the reinforced concrete formwork, specifically at the core positions of beams and columns within the formwork. The spacers in the formwork are positioned below the flanges of the end rings 5 ​​at both ends of the thin-walled steel pipes 1, providing support for the thin-walled steel pipes 1 in the beam structure. The connecting reinforcing bars 6 extending outward from the end rings 5 ​​in the column structure serve as temporary supports for the thin-walled steel pipes 1. The length of the connecting reinforcing bars 6 is 300mm pre-reserved according to the design. Reinforcing bars 2 are evenly distributed above and below the thin-walled steel pipes 1. In this example, the diameter of the reinforcing bars 2 is 20mm, but the diameter can be adjusted according to design strength requirements. Several stirrups 3 are installed outside the reinforcing bars 2 at the top and bottom of the thin-walled steel pipes 1. In this embodiment, the spacing of the stirrups 3 is 150mm, but the diameter and spacing can also be adjusted in real-time according to design strength requirements. Stirrups 3 are used to restrict the lateral expansion of concrete and prevent structural damage due to shear stress. The circular holes of the end flanges 5 correspond to the positions, shapes, and sizes of the reinforcing bars 2. The reinforcing bars 2 are passed through the holes of the end flanges 5. The reinforcing bars 2 between beams can be directly connected by compression through the reinforcing bar sleeves 7. However, the reinforcing bars 2 between beams and columns require bending the reinforcing bars 2 in the column structure to be in a straight line with the reinforcing bars 2 in the beam structure before being connected by compression using the reinforcing bar sleeves 7. After the beam structure and column structure are connected, concrete is poured outside the thin-walled steel pipe 1 to complete the installation.

[0047] In a preferred embodiment of the present invention, after the precast steel pipe is manufactured, a concrete pour can be performed first. The thin-walled steel pipe 1 of the beam and column is placed in the outer mold and the concrete is poured in the first pour. The mold leaves a 5 cm distance from the end flanges 5 at both ends of the thin-walled steel pipe 1, so that there is a 5 cm space between the end plates on both sides of the thin-walled steel pipe 1 and the concrete after the first pour. This space serves as a construction joint for the secondary pour on the construction site. After the concrete has completely solidified, the precast steel pipe is transported to the construction site. At the construction site, the beam structure and column structure are combined and connected according to the design, and the reserved construction joint is poured with concrete in the second pour at the connection node to strengthen the stability of the connection between the beam structure and the column structure, speed up the construction, and reduce the on-site construction period.

[0048] The filler inlet pipe 8 and overflow pipe 9 on the outside of the thin-walled steel pipe 1 can be fixed to the thin-walled steel pipe 1 by welding or threading. In this embodiment, the filler inlet pipe 8 and overflow pipe 9 on the outside of the thin-walled steel pipe 1 are fixed to the thin-walled steel pipe 1 by threading and bolting. The filler inlet pipe 8 is used to pour functional materials into the thin-walled steel pipe 1. The functional materials can be various materials such as shock-absorbing materials, sound-insulating materials or heat-insulating materials, so as to achieve the effects of earthquake resistance, sound insulation or heat insulation. The shock-absorbing functional material can be lightweight rubber concrete. Whether the shock-absorbing functional material needs to be poured can be determined according to the actual earthquake resistance requirements, or an appropriate amount of shock-absorbing functional material can be poured into the thin-walled steel pipe 1 according to the actual needs.

[0049] If the construction site needs to achieve a certain seismic resistance effect and requires pouring, and it is necessary to pour the entire space inside the thin-walled steel pipe 1, then it is necessary to judge whether the functional material inside the thin-walled steel pipe 1 has been completely poured according to the state of the overflow pipe 9. If there is overflow from the overflow pipe 9, then the pouring is complete. At this time, the filler inlet pipe 8 and the overflow pipe 9 are unscrewed from the thin-walled steel pipe 1 along the thread, and the original openings of the filler inlet pipe 8 and the overflow pipe 9 are sealed with micro-expansion pebbles concrete to ensure the sealing of the thin-walled steel pipe 1 after pouring.

[0050] When it is not necessary to completely pour functional materials into the thin-walled steel pipe 1, equipment pipelines can also be laid inside the thin-walled steel pipe 1. When making steel pipe prefabrication components, the pipelines can be reserved in the thin-walled steel pipe 1 in advance according to specific needs, which effectively solves the problem of occupying the internal space of the building, improves the aesthetics of the building, and increases the space utilization rate of the structure.

[0051] The beams and columns in this design have all undergone optimized design, taking into account the shape, structural features, and connection relationships of each component in detail. Calculations show that the overall weight of the components is reduced by 20%-30%, significantly reducing the structural resistance requirements, reducing material consumption and construction costs. At the same time, it increases the load-bearing capacity of the structure by 1.3-1.5 times and the ductility by 1.2-1.3 times.

[0052] Shear bearing capacity test: A three-point loading simulation test method is used on the precast steel pipe component. The load is applied at the midpoint of the precast steel pipe component, and supports are placed at both ends of the precast steel pipe component. This method is used to simulate the bending stress of beams and columns in actual use, and to test the bending performance and bending strength of the precast steel pipe component, and then to test its shear bearing capacity. Three-point loading simulation tests were conducted on both the partially internally reinforced steel pipe concrete beam-column structure ESTRC1 and the ordinary reinforced concrete beam-column structure RC, as shown in Table 1 below. The beam length of both ESTRC1 and RC is 2m, and their shear span ratio λ is 2. In ESTRC1, the width bt × height ht × thickness tw of the thin-walled steel pipe 1 is 150mm × 250mm × 6mm; the thickness h1 of the bottom outer concrete of the thin-walled steel pipe 1 is 100mm. Measurements of the width, height, and thickness of the thin-walled steel pipe 1 and the thickness of the outer concrete of the steel pipe are as follows: Figure 1 and Figure 2 The ordinary reinforced concrete beam-column structure shown in the figure does not have steel pipes inside.

[0053] Table 1

[0054]

[0055] Three-point loading simulation tests were conducted to record and compare data such as cracking load, cracking displacement, peak load, shear capacity, peak displacement, and displacement ductility coefficient of the steel pipes in the ESTRC1 concrete beam-column structure with locally integrated steel pipes and the RC ordinary reinforced concrete beam-column structure, as shown in Table 2 below. Simultaneously, load-displacement curves were plotted by recording loads and corresponding displacements at different time points, as shown in Table 2 below. Figure 13 As shown. From Figure 13As can be seen, the peak load that the concrete beam-column structure ESTRC1 with internal steel pipes can withstand is higher than that of the ordinary reinforced concrete beam-column structure RC, meaning that the bearing capacity of the concrete beam-column structure ESTRC1 with internal steel pipes is stronger. Before applying the peak load to both the concrete beam-column structure ESTRC1 with internal steel pipes and the ordinary reinforced concrete beam-column structure RC, when the same load is applied, the displacement change of the concrete beam-column structure ESTRC1 with internal steel pipes is smaller, meaning that the bearing capacity of the concrete beam-column structure ESTRC1 with internal steel pipes is stronger. After applying the peak load to both the concrete beam-column structure ESTRC1 with internal steel pipes and the ordinary reinforced concrete beam-column structure RC, the displacement change of the concrete beam-column structure ESTRC1 with internal steel pipes is more stable than that of the ordinary reinforced concrete beam-column structure RC, meaning that the bearing capacity of the concrete beam-column structure ESTRC1 with internal steel pipes is stronger.

[0056] Table 2

[0057]

[0058] in, Crack load, in kN; Crack displacement, in mm; Peak load (given by design requirements, and is known data in this embodiment), in kN; Shear capacity, unit: kN; Peak displacement, in mm; For: displacement ductility coefficient; The calculation is performed using the "general yield moment method", namely: ,in For: Yield load and corresponding displacement, taken as the displacement value when the load is reduced to 85% of the peak load. If the specimen terminates loading due to excessive deformation, the ultimate displacement Δu is the displacement value at the termination of loading. Shear bearing capacity. .

[0059] By comparing the above test data of the ESTRC1 concrete beam-column structure with partially internal steel pipes and the ordinary reinforced concrete beam-column structure RC, the shear bearing capacity of the ESTRC1 concrete beam-column structure with partially internal steel pipes can be determined. Compared to the shear bearing capacity of ordinary reinforced concrete beam-column structures The shear capacity of the ESTRC1 concrete beam-column structure with partially internal steel pipes increased from 253.21 to 480.915, meaning the shear capacity increased by 1.8 times; the ductility coefficient of the ESTRC1 concrete beam-column structure with partially internal steel pipes also increased. The ductility coefficient was increased from 3.7 to 4.9, which means the ductility coefficient increased by 1.3 times; while the weighing data in Table 1 shows that the concrete beam-column structure ESTRC1 with local internal steel pipes reduced its weight by 0.09t, which is a weight reduction of 20%.

[0060] Bending capacity test: A four-point loading simulation test method was used on the precast steel pipe component. The load was applied to the middle area of ​​the beam and column structure, while the supports were still located at both ends of the precast steel pipe component as the other two loading points. This method can generate a pure bending moment region in which the bending moment of the beam is constant. The four-point loading simulation test was carried out on the concrete beam-column structure ESTRC1 with partial internal steel pipe of the present invention and the ordinary reinforced concrete beam-column structure RC. As shown in Table 3 below, the beam length of the concrete beam-column structure ESTRC1 with partial internal steel pipe and the ordinary reinforced concrete beam-column structure RC is 2.9m. The width bt × height ht × thickness tw of the thin-walled steel pipe 1 in the concrete beam-column structure ESTRC1 with partial internal steel pipe is 150mm × 250mm × 6mm; the thickness h1 of the bottom outer concrete of the thin-walled steel pipe 1 in the concrete beam-column structure ESTRC1 with partial internal steel pipe is 100mm; the ordinary reinforced concrete beam-column structure RC does not have steel pipe inside.

[0061] Table 3

[0062]

[0063] Four-point loading simulation tests were conducted to record and compare data such as cracking load, cracking displacement, peak load, peak displacement, and displacement ductility coefficient of the steel pipes in the ESTRC1 concrete beam-column structure with locally embedded steel pipes and the RC ordinary reinforced concrete beam-column structure, as shown in Table 4 below. Simultaneously, by measuring the load and corresponding deflection values ​​at different time points, load-deflection curves were plotted to visually demonstrate the elastic changes of the ESTRC1 concrete beam-column structure with locally embedded steel pipes and the RC ordinary reinforced concrete beam-column structure under load, as shown in Table 4 below. Figure 14 As shown. From Figure 14 It can be seen that before the peak load is applied, under the same load, the deflection of the concrete beam-column structure ESTRC1 with local internal steel pipe is smaller, that is, the elastic change of the concrete beam-column structure ESTRC1 with local internal steel pipe is smaller; while after the peak load, the deflection change curve of the concrete beam-column structure ESTRC1 with local internal steel pipe tends to be stable, that is, the flexural bearing capacity of the concrete beam-column structure ESTRC1 with local internal steel pipe is stronger.

[0064] Table 4

[0065]

[0066] in, Crack load, in kN; Crack displacement, in mm; Peak load (given by design requirements, and is known data in this embodiment), in kN; Flexural bearing capacity, unit: kN; Peak displacement, in mm; For: displacement ductility coefficient; The calculation is performed using the "general yield moment method", namely: ,in The yield load and corresponding displacement are taken as the displacement value when the load is reduced to 85% of the peak load. If the specimen terminates loading due to excessive deformation, the ultimate displacement Δu is the displacement value at the termination of loading. Bending capacity. Where a is the distance between the loading points at both ends of the structure.

[0067] By comparing the above test data of the ESTRC1 concrete beam-column structure with partially internal steel pipes and the ordinary reinforced concrete beam-column structure RC, the shear bearing capacity of the ESTRC1 concrete beam-column structure with partially internal steel pipes can be determined. Compared to the flexural bearing capacity of ordinary reinforced concrete beam-column structures The flexural capacity of the ESTRC1 concrete beam-column structure with partially internal steel pipes increased from 243.96 to 446.91, meaning the flexural capacity increased by 1.8 times; the ductility coefficient of the ESTRC1 concrete beam-column structure with partially internal steel pipes also increased. The ductility coefficient was increased from 3.7 to 4.9, which means the ductility coefficient increased by 1.3 times; and the weighing data in Table 4 shows that the concrete beam-column structure ESTRC1 with local internal steel pipes reduced its weight by 0.09t, which is a weight reduction of 20%.

[0068] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A concrete beam-column structure with locally internally fitted thin-walled steel pipes, characterized in that, Thin-walled steel pipes (1) are installed in the core position of beams and columns. End wing rings (5) are installed at both ends of the thin-walled steel pipes (1). Connecting reinforcing bars (6) are welded on the end wing rings (5). Reinforcing bars (2) are installed on the thin-walled steel pipes (1). The reinforcing bars (2) pass through the end wing rings (5) at both ends of the thin-walled steel pipes (1). Concrete is poured around the outer periphery of the thin-walled steel pipes (1). Studs (4) are installed around the outer periphery of the thin-walled steel pipes (1). The thin-walled steel pipes (1) are tightly connected to the surrounding concrete through the studs (4). Openings are set at the upper and lower ends of the end wing rings (5) at both ends of the thin-walled steel pipes (1) corresponding to the positions of the reinforcing bars (2). Wire mesh (10) is fixed on the end wing rings (5) by welding. The reinforcing bars (2) at the upper and lower parts of the thin-walled steel pipes (1) pass through the wire mesh (10) through the openings and end wing rings (5).

2. The beam-column structure with locally internally fitted thin-walled steel pipes according to claim 1, characterized in that, The thin-walled steel pipe (1) is made by high-frequency plate rolling and welding process, and the material is Q355 steel.

3. A concrete beam-column structure with locally internally reinforced thin-walled steel pipes according to claim 2, characterized in that, The thin-walled steel pipe (1) has a filler inlet pipe (8) at one end and an overflow pipe (9) at the other end.

4. A concrete beam-column structure with locally internally reinforced thin-walled steel pipes according to claim 2, characterized in that, The studs (4) on the thin-walled steel pipe (1) are evenly distributed along the length of the thin-walled steel pipe (1), the length of the studs (4) is 6cm, and the diameter of the studs (4) is not less than 1cm.

5. A concrete beam-column structure with locally internally reinforced thin-walled steel pipes according to claim 1, characterized in that, The reinforcing bars (2) are placed at the top and bottom of the thin-walled steel pipe (1).

6. A concrete beam-column structure with locally internally reinforced thin-walled steel pipes according to claim 1, characterized in that, The thin-walled steel pipe (1) is fixed by several stirrups (3) on the outside of the upper and lower reinforcing bars (2).

7. A beam-column structure with locally internally fitted thin-walled steel pipes according to claim 6, characterized in that, The connection between the reinforcing bars (2) is achieved by extrusion connection through the reinforcing bar sleeve (7).

8. An installation method for a concrete beam-column structure with locally embedded thin-walled steel pipes, based on a beam-column structure with locally embedded thin-walled steel pipes (1) as described in any one of claims 1 to 7, characterized in that, End wing rings (5) are installed at both ends of the thin-walled steel pipe (1). Connecting reinforcing bars (6) are extended outward by welding on the outer side of the end wing rings (5) at both ends of the thin-walled steel pipe (1). Reinforcing bars (2) are set at the upper and lower parts of the thin-walled steel pipe (1). The beam and column are connected and fixed at the connection node by the reinforcing bars (2).

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