Self-resetting steel-concrete composite joint and its flexural bearing capacity calculation method
By designing a self-resetting steel-concrete composite joint, and utilizing a combination of energy-dissipating steel bars and friction energy-dissipating webs, the problems of low post-earthquake repair efficiency and poor energy dissipation capacity of prestressed connection joints are solved, achieving efficient assembly, easy repair, and good seismic performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- FUZHOU UNIV
- Filing Date
- 2026-04-14
- Publication Date
- 2026-06-02
AI Technical Summary
Existing prestressed precast concrete frame joints have low post-earthquake repair efficiency, large residual deformation, poor energy dissipation capacity, and are inconvenient to construct. Traditional energy dissipation components occupy space and are cumbersome to construct.
A self-resetting steel-concrete composite joint is adopted, which combines precast reinforced concrete columns, first and second steel beams, friction energy dissipation webs and tensile yield energy dissipation assemblies. Energy is dissipated by the buckling deformation of the energy dissipation steel bars and the sliding friction of the friction energy dissipation webs. Combined with the self-resetting ability of the prestressed steel strands, the flexural bearing capacity of each section is calculated to ensure structural stability.
It achieves efficient assembly, easy repair, small residual deformation, and strong energy dissipation capacity of the structure, reduces the risk of steel beam damage and premature yielding of prestressed steel strands, and improves construction safety and seismic performance.
Smart Images
Figure CN122129096A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of steel-concrete composite beam-column joints, and more particularly to a self-resetting steel-concrete composite joint and its flexural bearing capacity calculation method. Background Technology
[0002] Prestressed precast concrete frame joints are prone to collision damage at the beam-column interface due to the relative rotation of the connection, hindering post-earthquake repair and resulting in low repair efficiency. Furthermore, prestressing tendons typically require tensioning on the outer side of the span, posing challenges for high-altitude operations. Under seismic loads, these joints exhibit significant residual deformation and poor energy dissipation capacity. Adding ordinary steel reinforcement for energy dissipation presents difficulties for post-earthquake repair, while friction dampers and steel plates, while improving energy dissipation capacity, incur space requirements and complex construction requirements. Summary of the Invention
[0003] The purpose of this invention is to provide a self-resetting steel-concrete composite joint and its flexural bearing capacity calculation method. The structure has high assembly efficiency, small residual deformation, controllable loss, easy repair and good energy dissipation capacity, and good seismic performance.
[0004] To achieve the above objectives, the present invention provides a self-resetting steel-concrete composite joint, comprising a precast reinforced concrete column and a composite beam. A first steel beam is connected to one side of the precast reinforced concrete column via a first connecting plate, and a second steel beam is connected to one end of the composite beam. Prestressed steel strands are threaded through the composite beam, and one end of the prestressed steel strands is connected to the first steel beam. A friction energy-dissipating web is connected between the middle of the first steel beam and the second steel beam, and tensile yield energy-dissipating assemblies are connected between the upper sides of the first steel beam and the lower sides of the second steel beam.
[0005] As a further improvement of the present invention, each of the tensile yield energy dissipation assemblies includes two flange connecting plates arranged side by side and spaced apart, the two flange connecting plates being connected by at least two energy dissipation steel bars.
[0006] As a further improvement of the present invention, the energy-dissipating steel bars on the tensile yield energy-dissipating assembly are parallel to each other and arranged in a horizontal direction, and the energy-dissipating steel bars are parallel to the prestressed steel strands.
[0007] As a further improvement of the present invention, the energy-consuming steel bar has a contraction section in the middle, and the cross-sectional dimension of the contraction section of the energy-consuming steel bar is smaller than the cross-sectional dimensions of the two ends of the energy-consuming steel bar; the cross-sectional area of the contraction section of the energy-consuming steel bar is 0.7-0.9 of the cross-sectional area of the two ends of the energy-consuming steel bar.
[0008] As a further improvement of the present invention, the first steel beam includes a first vertical plate connected to a first connecting plate, and a first flat plate is connected to both the upper and lower sides of the first vertical plate. A first through hole is provided on the first vertical plate. The second steel beam includes a second vertical plate, and a second flat plate is connected to both the upper and lower sides of the second vertical plate. A second through hole is provided on the second vertical plate. The first vertical plate and the second vertical plate are arranged adjacent to each other at one end and sandwiched in the middle by two friction energy dissipation webs. A transversely arranged strip hole is provided on one side of the friction energy dissipation web, and a third through hole is provided on the other side. The strip hole and the first through hole are locked together by a first bolt, and the third through hole and the second through hole are locked together by a second bolt.
[0009] To achieve the above objectives, this invention also provides a method for calculating the flexural bearing capacity of a self-resetting steel-concrete composite joint. The connection section between the precast reinforced concrete column and the first connecting plate is section aa; the connection section between the first connecting plate and the first steel beam is section bb; the connection section of the friction-dissipating web at the joint between the first and second steel beams is section cc; and the vertical section of the composite beam is section dd. The flexural bearing capacity of section aa is M. a The flexural bearing capacity of section bb is M b The flexural bearing capacity of section cc is M c The flexural bearing capacity of section dd is M d The beam end shear forces corresponding to each section reaching its flexural bearing capacity are as follows: , , , The distance from section aa to the beam end is l, the distance from section aa to section bb is l1, the distance from section bb to section cc is l2, the distance from section cc to section dd is l3, and the distance from section dd to the beam end is l4. The beam end bearing capacity is determined by the minimum shear force. Control, then:
[0010]
[0011] The flexural bearing capacity of the self-centering steel-concrete composite joint is calculated using the above formula. .
[0012] As a further improvement of the present invention, the flexural bearing capacity M of the section aa a The calculation formula is as follows:
[0013] In the formula, : The effective cross-sectional area of the high-strength bolts; the precast reinforced concrete column is connected to the first connecting plate by high-strength bolts; The tensile strength of high-strength bolts; The total number of high-strength bolts arranged on the tension flange side of the precast reinforced concrete column; The distance between the centers of the upper and lower flanges of the steel beam.
[0014] As a further improvement of the present invention, the flexural bearing capacity M of the section bb b The calculation formula is as follows:
[0015] In the formula, : Yield strength of the flange steel near the beam-column junction; : Section modulus of elasticity of steel section.
[0016] As a further improvement of the present invention, the flexural bearing capacity M of the section cc c The calculation formula is as follows:
[0017] In the formula, The bending moment provided for the energy-consuming steel bar (72), The bending moment provided for the initial prestress, The bending moment provided by friction, The additional bending moment provided by the prestressed steel strands when the interface rotates; The axial force of the energy-dissipating steel bar This refers to the frictional force generated by the high-strength bolts at the web of the friction energy dissipation plate. For the first The initial prestress of the prestressed steel strand, This refers to the preload force of high-strength bolts; Yield strength of energy-consuming steel bars; : These represent the cross-sectional area of the energy-consuming steel bar and the effective area of a single prestressed steel strand, respectively; : These represent the elastic model of the energy-dissipating steel bar and the elastic modulus of the prestressed steel strand, respectively; : These represent the lengths of the energy-consuming steel bar and the prestressed steel strand, respectively; The relative rotation angle between the beam ends at the splice surface when the energy-consuming steel bar yields; : These represent the hole shape coefficient and friction coefficient of the high-strength bolt holes in the web, respectively; : These represent the number of high-strength bolts and the number of force-transmitting friction surfaces on one side of the friction energy dissipation web, respectively; d: Distance between the centers of the energy-dissipating steel bars at the top and bottom of the beam; d1: Distance from the center of the upper energy-dissipating steel bar to the center of the upper steel beam flange; d2: Distance from the center of the upper steel beam flange to the center of the upper steel strand; d3: Center distance between the upper and lower steel strands.
[0018] As a further improvement of the present invention, the flexural bearing capacity M of the section dd d The calculation formula is as follows: When satisfied hour:
[0019] Not satisfied hour:
[0020] In the formula: : These represent the yield strength of the steel reinforcement in the compression zone and tension zone, respectively; : These represent the cross-sectional areas of the reinforcing bars in the compression zone and tension zone, respectively; The magnitude of the axial compressive force of the section equivalent to the initial prestress; : These represent the vertical distances from the reinforcement bars in the compression zone and tension zone to the edge of the cross section, respectively; : Equivalent rectangular stress diagram coefficient, taken as 1.0; : Axial compressive strength of concrete; : These represent the cross-sectional width and the height of the compression zone, respectively; : These represent the relative limit pressure zone height, section height, and effective section height, respectively.
[0021] Beneficial effects Compared with the prior art, the advantages of the self-resetting steel-concrete composite joint and its flexural bearing capacity calculation method of the present invention are as follows: 1. In the tensile yield energy dissipation assembly, energy is dissipated by the buckling deformation of the energy-dissipating steel bar. This improves the energy dissipation capacity of the joint and reduces damage to the steel beam, while also preventing premature yielding of the prestressed steel strands. After the energy-dissipating steel bar yields due to an earthquake, only the tensile yield energy dissipation assembly needs to be replaced; the rest of the self-resetting steel-concrete composite joint does not require replacement, thus reducing maintenance costs.
[0022] 2. In each tensile yield energy dissipation assembly, the two flange connecting plates are connected by at least two energy dissipation steel bars. Compared with other shapes of structures, the energy dissipation steel bars have lower production costs, lower production difficulty, and faster production speed, which is conducive to the rapid and large-scale replacement of tensile yield energy dissipation assemblies after an earthquake.
[0023] 3. If the cross-sectional dimensions of the energy-dissipating steel bar are all the same, the location of the fracture is unpredictable should the energy-dissipating steel bar break during yielding. If the fracture occurs at the connection between the energy-dissipating steel bar and the flange connecting plate, and the earthquake continues after the fracture, the broken energy-dissipating steel bar will continue to swing up and down. During this process, the broken end of the energy-dissipating steel bar is prone to colliding with the first or second steel beam and causing damage. To solve this problem, a contraction section is provided in the middle of the energy-dissipating steel bar. The cross-sectional dimensions of the contraction section are smaller than those of the two ends of the energy-dissipating steel bar. Even if the energy-dissipating steel bar breaks, the fracture location is basically located at the contraction section, setting the fracture in a controllable position. That is, the energy-dissipating steel bar breaks in the middle. At this time, even if the broken ends of the energy-dissipating steel bar still swing up and down due to the earthquake, the two broken sections of the energy-dissipating steel bar are short in length and the swing amplitude is small, making it less likely to collide with the first or second steel beam, thus reducing the risk of damage to the steel beam.
[0024] 4. The friction energy dissipation web has transversely arranged strip holes to improve the rotation capacity of the steel-concrete composite beam and minimize the probability of damage to the composite beam and precast reinforced concrete columns during an earthquake.
[0025] 5. The connection method of tensioning prestressed steel strands in a single span beam is adopted, that is, the prestressed steel strands do not pass through the precast reinforced concrete columns. Compared with the connection method of the prestressed steel strands passing through the core area of the node, it can effectively avoid the impact of the prestressed steel strands when the core area of the node is damaged, and can also improve construction efficiency by pre-tensioning the steel strands, thereby avoiding high-altitude operations and improving construction safety.
[0026] 6. In the calculation method of the flexural bearing capacity of the self-resetting steel-concrete composite joint, the flexural bearing capacity of each section and the corresponding beam end shear force are calculated, and the flexural bearing capacity of the composite joint is obtained by using the minimum beam end shear force, so as to ensure the stability and feasibility of the calculated structure.
[0027] The invention will become clearer from the following description, taken in conjunction with the accompanying drawings, which are used to explain embodiments of the invention. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 A three-dimensional view of a self-resetting steel-concrete composite joint; Figure 2 This is the front view of a self-resetting steel-concrete composite joint. Figure 3 This is a magnified view of a self-resetting steel-concrete composite joint. Figure 4 for Figure 2 1-1 view; Figure 5 Layout diagram of the first steel beam, the second steel beam, the friction energy dissipation web, and the tensile yield energy dissipation assembly; Figure 6 This is a connection diagram of the first steel beam, the second steel beam, the friction energy dissipation web, and the tensile yield energy dissipation assembly. Figure 7 An enlarged view of the tensile yield energy dissipation assembly; Figure 8 This is a schematic diagram showing the positions of each section of a self-resetting steel-concrete composite joint. Figure 9 This is a schematic diagram of the calculation model for the flexural bearing capacity of section cc; Figure 10 This is one of the schematic diagrams for calculating the flexural bearing capacity of the cross section dd; Figure 11 This is the second schematic diagram of the calculation model for the flexural bearing capacity of the section dd. Detailed Implementation
[0030] Embodiments of the present invention will now be described with reference to the accompanying drawings.
[0031] Example Specific embodiments of the present invention are as follows: Figures 1 to 7As shown, a self-resetting steel-concrete composite joint includes a precast reinforced concrete column 1 and two composite beams 3, located on the left and right sides of the precast reinforced concrete column 1, respectively. The composite beams 3 are steel-concrete composite beams. A first steel beam 2 is connected to one side of the precast reinforced concrete column 1 via a vertically arranged first connecting plate 10. Specifically, the precast reinforced concrete column 1 is connected to the first connecting plate 10 via multiple high-strength bolts 11. A second steel beam 4 is connected to one end of the composite beam 3 near the precast reinforced concrete column 1. Four prestressed steel strands 6 are threaded through each composite beam 3, with one end of each strand connected to the first steel beam 2. A friction-dissipating web 5 connects the middle of the first steel beam 2 and the second steel beam 4. Tensile yield energy-dissipating assemblies 7 connect the upper and lower sides of both the first steel beam 2 and the second steel beam 4. The first steel beam 2 and the second steel beam 4 have the same height.
[0032] Among them, the prestressed steel strand 6 can be a standard steel strand made of seven steel wires twisted together, for example, with a nominal diameter of 15.2 mm.
[0033] The first steel beam 2 includes a first vertical plate 22 perpendicularly connected to the first connecting plate 10. First flat plates 23 are connected to both the upper and lower sides of the first vertical plate 22, and a vertically arranged reinforcing plate 24 is connected between the upper and lower first flat plates 23. One end of the first flat plate 23 is also connected to the first connecting plate 10. The first vertical plate 22 has three vertically arranged first through holes 21. The second steel beam 4 includes a second vertical plate 42 and a second connecting plate 41 connected to each other. The second vertical plate 42 and the second connecting plate 41 are perpendicular to each other. The second connecting plate 41 is vertically arranged and connected to the composite beam 3 at one end near the precast reinforced concrete column 1. Second flat plates 43 are connected to both the upper and lower sides of the second vertical plate 42, and the second flat plates 43 are also connected to the second connecting plate 41. The second vertical plate 42 has three vertically arranged second through holes 44. The first vertical plate 22 and the second vertical plate 42 are arranged adjacent to each other at one end and sandwiched between two friction energy-dissipating web plates 5, forming friction. Figure 4 As shown. The friction energy dissipation web 5 has three transversely arranged strip holes 51 on one side and three third through holes 52 on the other side. The strip holes 51 are locked to the first through hole 21 by a first bolt 81. During an earthquake, the first bolt 81 can slide along the length of the strip hole 51; the third through hole 52 is locked to the second through hole 44 by a second bolt 82.
[0034] An anchor plate 9 is connected to one end of the composite beam 3 away from the precast reinforced concrete column 1. The anchor plate 9 is provided with a first anchor nut 61, and the reinforcing plate 24 of the first steel beam 2 is provided with a second anchor nut 62. The prestressed steel strand 6 passes through the anchor plate 9, the composite beam 3, the second connecting plate 41, and the reinforcing plate 24 in sequence. The two ends of the prestressed steel strand 6 are threadedly connected to the first anchor nut 61 and the second anchor nut 62, respectively. The preload of the steel strand can be adjusted by the first anchor nut 61 and the second anchor nut 62.
[0035] Each tensile yield energy dissipation assembly 7 includes two parallel and spaced-apart flange connecting plates 71, which are connected by at least two energy-dissipating steel bars 72. The two flange connecting plates 71 are respectively connected to the first steel beam 2 and the second steel beam 4. In this embodiment, the two flange connecting plates 71 are connected by four energy-dissipating steel bars 72, such as... Figure 7 As shown, the two flange connecting plates 71 in the tensile yield energy dissipation assembly 7 are connected to the first plate 23 of the first steel beam 2 and the second plate 43 of the second steel beam 4 respectively by four third bolts 73.
[0036] The energy-dissipating steel bars 72 on the tensile yield energy-dissipating assembly 7 are parallel to each other and arranged in a horizontal direction, and the energy-dissipating steel bars 72 are parallel to the prestressed steel strands 6.
[0037] In this embodiment, the energy-dissipating steel rod 72 has a contraction section 721 in the middle, and the cross-sectional dimension of the contraction section 721 is smaller than the cross-sectional dimensions of the two ends of the energy-dissipating steel rod 72. The cross-sectional area of the contraction section 721 is 0.7-0.9 times the cross-sectional area of the two ends of the energy-dissipating steel rod 72. Both the contraction section 721 and the two ends of the energy-dissipating steel rod 72 are cylindrical, and they are connected by a conical surface.
[0038] The calculation method for the flexural bearing capacity of the self-resetting steel-concrete composite joint is as follows: First, the connection section between the precast reinforced concrete column 1 and the first connecting plate 10 is section aa; the connection section between the first connecting plate 10 and the first steel beam 2 is section bb; the connection section of the friction energy dissipation web 5 at the splice between the first steel beam 2 and the second steel beam 4 is section cc; and the vertical section of the composite beam 3 is section dd. Figures 8 to 11 As shown. The flexural bearing capacity of section aa is M. a The flexural bearing capacity of section bb is M b The flexural bearing capacity of section cc is M c The flexural bearing capacity of section dd is M d .
[0039] The flexural bearing capacity M of section aa a The calculation formula is as follows:
[0040] In the formula, : Effective cross-sectional area of high-strength bolt 11; The tensile strength of high-strength bolt 11; The total number of the two rows of high-strength bolts 11 arranged on the tension flange side of the precast reinforced concrete column 1 is 12 in this embodiment; The distance between the centers of the upper and lower flanges of the steel beam is the distance between the centers of the upper and lower first flat plates 23.
[0041] The flexural bearing capacity M of section bb b The calculation formula is as follows:
[0042] In the formula, : Yield strength of flange steel near the beam-column junction, i.e., yield strength at the connection between the upper and lower first flat plates 23 and the first connecting plate 10; : Section modulus of elasticity of steel section.
[0043] The flexural bearing capacity M of section cc c The calculation formula is as follows:
[0044] In the formula, The bending moment provided for the energy-consuming steel bar 72 The bending moment provided for the initial prestress, The bending moment provided by friction, Additional bending moment provided by the prestressed steel strand 6 when the interface rotates; The axial force of the energy-consuming steel bar 72 The frictional force generated by the five high-strength bolts 11 at the web plate is used for friction energy dissipation. For the first The initial prestress of prestressed steel strand 6, Preload for high-strength bolt 11; Yield strength of energy-consuming steel bar 72; : These represent the cross-sectional area of the energy-consuming steel bar 72 and the effective area of a single prestressed steel strand 6, respectively; : These represent the elastic model of the energy-dissipating steel bar 72 and the elastic modulus of the prestressed steel strand 6, respectively; : These represent the lengths of the energy-consuming steel bar 72 and the prestressed steel strand 6, respectively; The relative rotation angle of the beam end at the splice surface when the energy-consuming steel bar 72 yields; : These represent the hole shape coefficient and friction coefficient of the high-strength bolt hole (i.e., the third through hole 52) at the web. : These represent the number of high-strength bolts 11 on one side of the friction energy dissipation web 5 and the number of force transmission friction surfaces, respectively; d: Center distance between the upper and lower energy-dissipating steel bars 72 of the second steel beam 4; d1: The distance from the center of the upper energy-dissipating steel bar 72 to the center of the upper steel beam flange, that is, the distance from the center of the upper energy-dissipating steel bar 72 to the center of the second plate 43 at the upper end of the second steel beam 4; d2: The distance from the center of the upper steel beam flange to the center of the upper steel strand 6, that is, the distance from the center of the second plate 43 at the upper end of the second steel beam 4 to the center of the upper steel strand 6; d3: Center distance between the upper and lower steel strands.
[0045] The flexural bearing capacity M of section dd d The calculation formula is as follows: When satisfied hour:
[0046] Not satisfied hour:
[0047] In the formula: : These represent the yield strength of the steel reinforcement in the compression zone and tension zone, respectively; : These represent the cross-sectional areas of the reinforcing bars in the compression zone and tension zone, respectively; The magnitude of the axial compressive force of the section equivalent to the initial prestress; : These represent the vertical distances from the reinforcement bars in the compression zone and tension zone to the edge of the cross section, respectively; : Equivalent rectangular stress diagram coefficient, taken as 1.0; : Axial compressive strength of concrete; : These represent the cross-sectional width and the height of the compression zone, respectively; : These represent the relative limit pressure zone height, section height, and effective section height, respectively.
[0048] The beam end shear forces corresponding to each section reaching its flexural bearing capacity are as follows: , , , The distance from section aa to the beam end is l, the distance from section aa to section bb is l1, the distance from section bb to section cc is l2, the distance from section cc to section dd is l3, and the distance from section dd to the beam end is l4. The beam end bearing capacity is determined by the minimum shear force. Control, therefore, the flexural bearing capacity of the nodal region The calculation formula is:
[0049] The bending bearing capacity of the node area can be obtained through the above calculation steps. .
[0050] This self-resetting steel-concrete composite joint allows for the complete replacement of the tensile yield energy dissipation assembly. It utilizes the buckling deformation of the energy-dissipating steel bars for energy dissipation, improving the joint's energy dissipation capacity while reducing steel beam damage and preventing premature yielding of the prestressed steel strands. Compared to connections where the steel strands penetrate the joint's core area, the single-span prestressed steel strand tensioning effectively avoids the impact on the prestressed steel strands in the event of core area failure and improves construction efficiency by pre-tensioning the steel strands, thus avoiding high-altitude work. The friction energy-dissipating web has transversely arranged strip holes to enhance the rotational capacity of the steel-concrete composite beam. This joint dissipates energy through the buckling deformation of the energy-dissipating steel bars and the sliding friction of the friction energy-dissipating web, while providing self-resetting capability through post-tensioned unbonded prestressed steel strands. After an earthquake, it can be reused by completely replacing the tensile yield energy dissipation assembly.
[0051] The tensile yield energy dissipation assembly can also concentrate the plastic deformation of the node on the energy dissipation steel bar, thereby effectively reducing the plastic damage of the steel beam. It can also improve the stiffness of the rotating section, thereby reducing the stress change rate of the prestressed steel strand and preventing the prestressed steel strand from yielding too early. After the earthquake, the function can be restored by replacing the tensile yield energy dissipation assembly, making it easier to achieve post-earthquake functional restoration.
[0052] Due to the addition of the tensile yield energy dissipation assembly and prestressed steel strands, the self-resetting steel-concrete composite joint exhibits excellent energy dissipation and self-resetting capabilities. At the same time, its bearing capacity is superior to that of joints with only tensile yield energy dissipation assemblies or prestressed steel strands, indicating that the proposed novel self-resetting steel-concrete composite joint has better seismic performance.
[0053] The frame with the new self-resetting steel-concrete composite joint exhibits good load-bearing capacity and self-resetting ability, which can provide the possibility for post-earthquake repair. It is recommended that reinforcement measures be taken for the column bases of this type of frame in actual engineering to further improve the seismic performance of the frame.
[0054] In the above embodiments, the nodes are planar nodes that connect two beams on the left and right. In addition to the above embodiments, the present invention is still effective for other node types such as edge nodes and spatial nodes corresponding to the actual structure (i.e., the case where beams are set in both the in-plane and out-of-plane vertical directions). In this case, the corresponding bolt holes are set at the square steel tubes on the column to connect with the beams in the direction perpendicular to the paper.
[0055] The present invention has been described above in conjunction with the preferred embodiments, but the present invention is not limited to the embodiments disclosed above, but should cover various modifications and equivalent combinations made in accordance with the essence of the present invention.
Claims
1. A self-resetting steel-concrete composite joint, comprising a precast reinforced concrete column (1) and a composite beam (3), characterized in that, A first steel beam (2) is connected to one side of a precast reinforced concrete column (1) via a first connecting plate (10). A second steel beam (4) is connected to one end of a composite beam (3). A prestressed steel strand (6) is threaded through the composite beam (3). One end of the prestressed steel strand (6) is connected to the first steel beam (2). A friction energy dissipation web (5) is connected between the middle of the first steel beam (2) and the second steel beam (4). Tensile yield energy dissipation assemblies (7) are connected between the upper sides of the first steel beam (2) and the lower sides of the second steel beam (4).
2. The self-resetting steel-concrete composite joint according to claim 1, characterized in that, Each of the tensile yield energy dissipation assemblies (7) includes two parallel and spaced flange connecting plates (71), which are connected by at least two energy dissipation steel bars (72). The two flange connecting plates (71) are respectively connected to the first steel beam (2) and the second steel beam (4); the composite beam (3) is a steel-concrete composite beam.
3. A self-resetting steel-concrete composite joint according to claim 2, characterized in that, The energy-dissipating steel bars (72) on the tensile yield energy-dissipating assembly (7) are parallel to each other and arranged in the horizontal direction, and the energy-dissipating steel bars (72) are parallel to the prestressed steel strands (6).
4. A self-resetting steel-concrete composite joint according to claim 2, characterized in that, The energy-consuming steel bar (72) has a contraction section (721) in the middle. The cross-sectional dimension of the contraction section (721) of the energy-consuming steel bar (72) is smaller than the cross-sectional dimensions at both ends of the energy-consuming steel bar (72). The cross-sectional area of the contraction section (721) of the energy-consuming steel bar (72) is 0.7-0.9 of the cross-sectional area at both ends of the energy-consuming steel bar (72).
5. A self-resetting steel-concrete composite joint according to claim 2, characterized in that, The first steel beam (2) includes a first vertical plate (22) connected to the first connecting plate (10). The upper and lower sides of the first vertical plate (22) are connected to the first flat plate (23). The first vertical plate (22) is provided with a first through hole (21). The second steel beam (4) includes a second vertical plate (42). The upper and lower sides of the second vertical plate (42) are connected to the second flat plate (43). The second vertical plate (42) is provided with a second through hole (44). The first vertical plate (22) and the second vertical plate (42) are arranged adjacent to each other at one end and sandwiched in the middle by two friction energy dissipation web plates (5). The friction energy dissipation web plate (5) is provided with a transversely arranged strip hole (51) on one side and a third through hole (52) on the other side. The strip hole (51) is locked to the first through hole (21) by a first bolt (81), and the third through hole (52) is locked to the second through hole (44) by a second bolt (82).
6. The method for calculating the flexural bearing capacity of a self-resetting steel-concrete composite joint according to claim 1, characterized in that, The connection section between the precast reinforced concrete column (1) and the first connecting plate (10) is section aa; the connection section between the first connecting plate (10) and the first steel beam (2) is section bb; the connection section of the friction energy dissipation web (5) at the splice of the first steel beam (2) and the second steel beam (4) is section cc; the vertical section of the composite beam (3) is section dd; the flexural bearing capacity of section aa is M. a The flexural bearing capacity of section bb is M b The flexural bearing capacity of section cc is M c The flexural bearing capacity of section dd is M d The beam end shear forces corresponding to each section reaching its flexural bearing capacity are as follows: , , , The distance from section aa to the beam end is l, the distance from section aa to section bb is l1, the distance from section bb to section cc is l2, the distance from section cc to section dd is l3, and the distance from section dd to the beam end is l4. The beam end bearing capacity is determined by the minimum shear force. Control, then: The flexural bearing capacity of the self-centering steel-concrete composite joint is calculated using the above formula. .
7. The method for calculating flexural bearing capacity according to claim 6, characterized in that, The flexural bearing capacity M of section aa a The calculation formula is as follows: In the formula, : The effective cross-sectional area of the high-strength bolt (11); the precast reinforced concrete column (1) is connected to the first connecting plate (10) by the high-strength bolt (11); : Tensile strength of high-strength bolt (11); : The total number of high-strength bolts (11) arranged on the tension flange side of the precast reinforced concrete column (1); The distance between the centers of the upper and lower flanges of the steel beam.
8. The method for calculating flexural bearing capacity according to claim 6, characterized in that, The flexural bearing capacity M of the section bb b The calculation formula is as follows: In the formula, : Yield strength of the flange steel near the beam-column junction; : Section modulus of elasticity of steel section.
9. The method for calculating flexural bearing capacity according to claim 6, characterized in that, The flexural bearing capacity M of the section cc c The calculation formula is as follows: In the formula, The bending moment provided for the energy-consuming steel bar (72), The bending moment provided for the initial prestress, The bending moment provided by friction, Additional bending moment provided by the prestressed steel strand (6) when the interface rotates; The axial force of the energy-consuming steel bar (72) The frictional force generated by the high-strength bolts (11) at the web (5) for friction energy dissipation. For the first The initial prestress of the prestressed steel strand (6), Preload of high-strength bolt (11); Yield strength of energy-consuming steel bar (72); : These represent the cross-sectional area of the energy-consuming steel bar (72) and the effective area of a single prestressed steel strand (6), respectively; : These represent the elastic model of the energy-dissipating steel bar (72) and the elastic modulus of the prestressed steel strand (6), respectively; : These represent the lengths of the energy-consuming steel bar (72) and the prestressed steel strand (6), respectively; The relative rotation angle of the beam end at the splice surface when the energy-consuming steel bar (72) yields; : These represent the hole shape coefficient and friction coefficient of the high-strength bolt holes in the web, respectively; : These represent the number of high-strength bolts (11) on one side of the friction energy dissipation web (5) and the number of force transmission friction surfaces, respectively; d: Center distance between the upper and lower energy-dissipating steel bars (72) of the beam; d1: Distance from the center of the upper energy-consuming steel bar (72) to the center of the upper steel beam flange; d2: Distance from the center of the upper steel beam flange to the center of the upper steel strand (6); d3: Center distance between the upper and lower steel strands (6).
10. The method for calculating flexural bearing capacity according to claim 6, characterized in that, The flexural bearing capacity M of the section dd d The calculation formula is as follows: When satisfied hour: Not satisfied hour: In the formula: : These represent the yield strength of the steel reinforcement in the compression zone and tension zone, respectively; : These represent the cross-sectional areas of the reinforcing bars in the compression zone and tension zone, respectively; The magnitude of the axial compressive force of the section equivalent to the initial prestress; : These represent the vertical distances from the reinforcement bars in the compression zone and tension zone to the edge of the cross section, respectively; : Equivalent rectangular stress diagram coefficient, taken as 1.0; : Axial compressive strength of concrete; : These represent the cross-sectional width and the height of the compression zone, respectively; : These represent the relative limit pressure zone height, section height, and effective section height, respectively.