Through type edge sealing concrete beam and cantilever steel beam junction joint and design method
By installing reinforced concrete corbels, longitudinal steel bars, stirrups and other structural measures at the junction of the cantilevered steel beam and the edge-sealed concrete beam, the problems of low force transmission efficiency and poor seismic performance of traditional nodes were solved, efficient and convenient rigid connection was achieved, and the safety of the structure and construction efficiency were improved.
Patent Information
- Application Number
- CN202511020289.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-23
- Publication Date
- 2025-09-26
AI Technical Summary
The junction between traditional cantilever steel beams and edge-sealed concrete beams has poor seismic performance, complex construction and high cost, and is unable to effectively transmit bending moments, resulting in weak links in the structure and difficulty in achieving rigid connections.
By adopting the junction node of through-type edge-sealed concrete beam and cantilevered steel beam, and setting reinforced concrete corbels and longitudinal through-steel bars, stirrups and other structural measures, a closed load-bearing space is formed, which improves the node stiffness and shear bearing capacity and simplifies construction.
It effectively transmits internal forces, improves node stiffness and shear bearing capacity, reduces on-site embedded parts and welding work, reduces construction costs, and enhances structural safety.
Smart Images
Figure CN120701009A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of structural engineering technology, and specifically relates to a junction node between a through-type edge-sealed concrete beam and a cantilevered steel beam and a design method thereof, which is suitable for the rigid connection of components made of different materials in a steel-concrete hybrid structure of a high-rise building. Background Art
[0002] With the acceleration of urbanization and the diversification of building functions, steel-concrete hybrid structural systems are widely used in super-high-rise buildings, combining the lightweight and high strength of steel with the fire and corrosion resistance of concrete. In such structures, the junctions between steel and concrete components are critical force transmission points, and their performance directly affects the overall structural safety.
[0003] The interface between the cantilevered steel beam and the edge-sealed concrete beam presents a sudden change in material and structure, resulting in highly complex mechanical properties. As a critical node connecting two dissimilar materials and transmitting surrounding loads, the interface is a vulnerable link. Actual earthquake damage analysis has also shown that improper structural treatment of this interface can lead to concentrated deformation and damage in components under earthquake action, potentially causing failure. Therefore, the performance and construction of the interface node are crucial to the overall structure.
[0004] Traditional junction nodes mostly use embedded parts hinged connection, and are connected by bolts or welding. Although this method can alleviate structural mutations caused by material differences, it has significant defects: low node redundancy leads to insufficient seismic energy absorption capacity; it cannot effectively transmit bending moments, which weakens the collaborative work between steel and concrete; the workload of on-site welding is large, and the embedded parts require high precision; the excessive amount of steel increases construction costs. Actual earthquake damage analysis shows that such nodes often experience stress concentration under the action of earthquakes, causing the junction area to become a structural weak link. In addition, in some special cases, reinforced concrete beams need to be overlapped on steel beams for connection. How to effectively connect reinforced concrete beams with steel beams is a difficult problem in the engineering community.
[0005] Therefore, this field urgently needs an intersection node solution that can achieve rigid connection, improve node integrity, simplify construction technology and be economical and efficient, so as to meet the dual requirements of modern buildings for structural safety and construction efficiency. Summary of the Invention
[0006] In response to the shortcomings of the existing technology, the present invention provides a junction node and design method for a through-type edge-sealed concrete beam and a cantilevered steel beam. Through an innovative reinforced concrete corbel structure, it solves the problems of low force transmission efficiency, poor seismic performance, and complex construction of traditional nodes.
[0007] In order to solve the above technical problems, the present invention provides a through-type edge-sealed concrete beam and cantilever steel beam junction node, comprising: Cantilevered steel beams, edge-sealed concrete beams, and reinforced concrete corbels wrapped around the junction of the two; The node also includes: Upper reinforcement, lower reinforcement, stirrups and waist reinforcement arranged within a certain height range of reinforced concrete corbel; An edge-sealed concrete beam that is arranged throughout a certain height range on one or both sides of the reinforced concrete corbel.
[0008] Furthermore, when the cantilever steel beam is connected to the edge-sealed concrete beam on only one side: The certain height range of the reinforced concrete corbel is the cantilever steel beam height plus 100 mm; The reinforced concrete corbel is located in the area above the upper flange of the cantilevered steel beam and the upper reinforcement is provided; The reinforced concrete corbel is located in the area below the lower flange of the cantilevered steel beam and the lower reinforcement is provided; The reinforced concrete corbel stirrups are arranged at intervals along the length of the reinforced concrete corbel; Reinforced concrete corbel waist reinforcement, arranged in the edge area of the reinforced concrete corbel; The upper longitudinal reinforcement of the edge-sealed concrete beam extends into the opposite side of the reinforced concrete corbel and bends downward; The longitudinal reinforcement at the lower part of the edge-sealed concrete beam extends into the opposite side of the reinforced concrete corbel, passes through the web of the cantilevered steel beam and then bends upward; The longitudinal reinforcement of the floor slab on one side of the edge-sealed concrete beam extends into the opposite side of the reinforced concrete corbel and bends downward; Transverse stiffening ribs are arranged along the longitudinal direction of the cantilevered steel beam.
[0009] Furthermore, when both sides of the cantilevered steel beam are connected to edge-sealed concrete beams: The certain height range of the reinforced concrete corbel is the cantilever steel beam height plus 100 mm; The reinforced concrete corbel is located in the area above the upper flange of the cantilevered steel beam and the upper reinforcement is provided; The reinforced concrete corbel is located in the area below the lower flange of the cantilevered steel beam and the lower reinforcement is provided; The reinforced concrete corbel stirrups are arranged at intervals along the length of the reinforced concrete corbel; Reinforced concrete corbel waist reinforcement, arranged in the edge area of the reinforced concrete corbel; The upper longitudinal reinforcement of the edge-sealed concrete beam passes through the reinforced concrete corbel; The longitudinal reinforcement at the lower part of the edge-sealed concrete beam passes through the reinforced concrete corbel and the web of the cantilevered steel beam; The longitudinal reinforcement of the floor slabs on both sides passes through the reinforced concrete corbels.
[0010] Furthermore, when the floor slab elevations of the edge-sealed concrete beams on both sides of the cantilevered steel beam are different: The upper longitudinal reinforcement of the edge-sealed concrete beam passes through the reinforced concrete corbel; The longitudinal reinforcement at the bottom of the edge-sealed concrete beam passes through the reinforced concrete corbel, passes through the web of the cantilevered steel beam and then bends upward; The longitudinal reinforcement of the high floor slab passes through the reinforced concrete corbel and bends downward; The longitudinal reinforcement of the lower floor slab passes through the reinforced concrete corbel, passes through the web of the cantilevered steel beam and then bends upward; Transverse stiffening ribs are arranged along the longitudinal direction of the cantilevered steel beam.
[0011] Furthermore, the outer coverage range of the reinforced concrete corbel along the longitudinal length of the cantilever steel beam is the width of the edge-sealed concrete beam plus 300 mm, and the length along the span direction of the edge-sealed concrete beam is the width of the cantilever steel beam plus 150 mm.
[0012] Furthermore, when the cantilevered steel beam overlaps multiple edge-sealed concrete beams or the beams on both sides are not in the same straight line: The longitudinal length of the reinforced concrete corbel is the distance between the two farthest edge-sealed concrete beams plus 300 mm; The length in the span direction is the width of the cantilever steel beam plus 150 mm.
[0013] Furthermore, the length of the straight section of the upper and lower longitudinal reinforcements of the edge-sealed concrete beam and the floor slab longitudinal reinforcement after bending is not less than 12 times the diameter D of the reinforcement.
[0014] Furthermore, the web of the cantilevered steel beam has openings for the longitudinal reinforcement of the lower portion of the edge-sealed concrete beam to pass through; The transverse stiffening ribs are made of Q355C, with the same thickness as the web of the cantilever steel beam, and are connected by groove welds or fillet welds.
[0015] On the other hand, the present application also seeks protection for a design method of the above-mentioned node, comprising: S1: The bending capacity of the cantilever steel beam is calculated according to the following formula:
[0016] Where: M —Bending moment at the end of the steel beam; γ ——Plastic development coefficient of steel beam section, 1.05 for I-section; W ——net section modulus of steel beam; f ——Bending strength coefficient of steel; S2: The shear bearing capacity of the cantilever steel beam is calculated according to the following formula:
[0017] Where: V — shear force on the ends of the steel beam; I——moment of inertia of the gross section of the steel beam; S - Calculate the area moment of the gross section above or below the shear stress about the neutral axis; t w ——the thickness of the web of the steel beam; f v ——Steel shear strength coefficient; S3: The bending bearing capacity of the normal section of the edge-sealed reinforced concrete beam is calculated according to the following formula:
[0018]
[0019] And should meet the following requirements:
[0020]
[0021] When the above conditions are not met, the following formula should be used:
[0022] Where: M u —Bending moment on the cross section of a pure reinforced concrete beam; α 1——Approximate value coefficient according to the specification; f c ——Design value of concrete axial compressive strength; f y 、 f y ’ ——Design values of tensile and compressive strength of steel bars; A s 、 A s ’ — cross-sectional area of longitudinal reinforcement in tension and compression zones; b — Cross-sectional width of edge-sealed reinforced concrete beams; h 0——Effective height of edge-sealed reinforced concrete beam section; ζ b ——height of relative limit pressure zone; a s ’ - the distance from the point of resultant force of the compressive longitudinal reinforcement to the compressive edge of the section; x ——Height of the cross section of the compression zone.
[0023] Further: To ensure the rationality of the initial section, the shear section verification should be performed before calculating the shear bearing capacity of the inclined section of the edge-sealed reinforced concrete beam: when h 0 / b ≤4:
[0024] when h 0 / b ≥6 hours:
[0025] When 4< h 0 / b When <6, it is determined by linear interpolation; Where: V ——Design value of the maximum shear bearing capacity of the inclined section of edge-sealed reinforced concrete beam; β c ——Concrete strength influence coefficient.
[0026] Beneficial technical effects: The present invention proposes a construction method for the junction of a through-type edge-sealed concrete beam and a cantilevered steel beam. Compared with traditional methods, this junction can effectively transmit internal forces and ensure node rigidity. The junction area is composed of a cantilevered steel beam, an edge-sealed concrete beam, a reinforced concrete corbel, longitudinal through-steel bars, and transverse stirrups. As an efficient and convenient junction at the junction of different materials, its characteristics are: (1) By setting reinforced concrete corbels at the junction, while ensuring that the concrete in the junction area effectively constrains the end of the cantilevered steel beam, structural measures such as through longitudinal reinforcement and stirrups are added to significantly improve the shear bearing capacity of the node junction.
[0027] (2) Considering the restraining effect of the edge-sealed concrete beam and the floor slab on the flange of the cantilever steel beam, a closed force space is formed. This is not only beneficial to the overall stability of the cantilever steel beam and improves the structural safety, but also can fully guarantee the node stiffness and effectively transfer the bending moment and shear force of the edge-sealed concrete beam to the cantilever steel beam, making the force transmission path of the structure more reliable. (3) Concrete components do not require embedded parts, which reduces the on-site component embedding and welding work, makes construction convenient, and has good economy. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0029] Figure 1 This is a schematic diagram of the cantilevered steel beams and the edge-sealed concrete beams for this application; Figure 2 This is a schematic diagram of the cantilevered steel beams overlapped with edge-sealed concrete beams (multiple runs) for this application; Figure 3 Schematic diagram of a cantilevered steel beam with edge-sealed concrete beam on only one side for this application; Figure 4 Schematic diagram of cantilevered steel beams with sealed edge concrete beams on both sides for this application; Figure 5 This is a schematic diagram of the cantilevered steel beams overlapped with the edge-sealed concrete beams (drop slabs) for this application; Figure 6 Schematic diagram of cantilevered steel beams with edge-sealed concrete beams (drop slabs) on both sides for this application; Figure 7 This is a top view of the cantilevered steel beams and the edge-sealed concrete beams in this application; Figure 8 This is a top view schematic diagram of the cantilevered steel beams and edge-sealed concrete beams (multiple tracks) overlapped in this application.
[0030] Among them, 1. Cantilever steel beam; 2. Edge-sealed concrete beam; 3. Reinforced concrete corbel; 4. Upper reinforcement of reinforced concrete corbel; 4A. Lower reinforcement of reinforced concrete corbel; 5. Stirrups of reinforced concrete corbel; 6. Waist reinforcement of reinforced concrete corbel; 7. Floor slab; 8. Transverse stiffener; 9. Upper longitudinal reinforcement of edge-sealed concrete beam; 9A. Lower longitudinal reinforcement of edge-sealed concrete beam; H1 Width of edge-sealed concrete beam; H2 External coverage of reinforced concrete corbel (along the longitudinal direction of cantilever steel beam); H3 Distance between the two farthest edge-sealed concrete beams; H4 External coverage of reinforced concrete corbel (along the span direction of edge-sealed concrete beam); h1 Elevation when floor slab is at a high place; h2 Elevation when floor slab is at a low place. DETAILED DESCRIPTION
[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.
[0032] like Figure 1-6 As shown, the technical solution adopted by the present invention to solve the key technical problems is: using the upper steel bars 4 of the reinforced concrete corbel and the lower steel bars 4A of the reinforced concrete corbel, the reinforced concrete corbel stirrups 5 and the reinforced concrete corbel waist bars 6 to form a reinforced concrete corbel 3, and the reinforced concrete corbel 3 is outsourced to the junction of the edge-sealed concrete beam 2 and the cantilever steel beam 1 to transmit internal force. Figure 1 In the figure, H1 is the width of the edge-sealed concrete beam, and H2 is the outer coverage range of the reinforced concrete corbel.
[0033] When a cantilever steel beam has a sealed concrete beam on only one side, upper longitudinal reinforcement 4D22 (D is the bar diameter, the rest are the same) and lower longitudinal reinforcement 4D22, stirrups D12@150, and waist reinforcement D12@150 are arranged within a certain height range of the reinforced concrete corbel (usually the cantilever steel beam height + 100 mm). The upper longitudinal reinforcement 9 of the sealed concrete beam extends into the opposite side of the reinforced concrete corbel and bends downward. The lower longitudinal reinforcement 9A of the sealed concrete beam extends into the opposite side of the reinforced concrete corbel, passes through the cantilever steel beam web, and bends upward. The longitudinal reinforcement 7 of the floor slab on one side of the sealed concrete beam extends into the opposite side of the reinforced concrete corbel and bends downward. Transverse stiffeners 8 are provided along the longitudinal direction of the cantilever steel beam.
[0034] When both sides of a cantilever steel beam are enclosed by edge-sealed concrete beams, upper and lower longitudinal bars (4D22, 4D22), stirrups (D12@150, and D12@150) are arranged within a certain height range of the reinforced concrete corbel (typically the cantilever steel beam height + 100 mm). Upper longitudinal bars (9) of the edge-sealed concrete beam extend through the reinforced concrete corbel; lower longitudinal bars (9A) extend through the reinforced concrete corbel and pass through the cantilever steel beam web. Longitudinal bars (7) of the floor slabs on both sides of the edge-sealed concrete beam extend through the reinforced concrete corbel. Transverse stiffeners (8) are optional for cantilever steel beams.
[0035] When both sides of a cantilevered steel beam are surrounded by edge-sealed concrete beams and the floor slab elevations are different, upper longitudinal bars 4D22, lower longitudinal bars 4D22, stirrups D12@150, and waist bars D12@150 are arranged within a certain height range of the reinforced concrete corbel (this range is usually the cantilevered steel beam height + 100 mm). The upper longitudinal bars 9 of the edge-sealed concrete beam pass through the reinforced concrete corbel; the lower longitudinal bars 9A of the edge-sealed concrete beam pass through the reinforced concrete corbel, pass through the cantilevered steel beam web, and bend upward; at the higher elevation, h 1. The longitudinal reinforcement of the edge-sealed concrete beam floor passes through the reinforced concrete corbel and bends downward; located at the lower elevation h The longitudinal reinforcement of the edge-sealed concrete beam floor slabs at two locations passes through the reinforced concrete corbels, passes through the web of the cantilevered steel beam, and bends upward; transverse stiffening ribs 8 are provided along the longitudinal direction of the cantilevered steel beam.
[0036] In this embodiment, the outer coverage range of the reinforced concrete corbel along the longitudinal length H2 of the cantilever steel beam is the width of the edge-sealed concrete beam + 300 mm, and the outer coverage range of the reinforced concrete corbel along the span direction of the edge-sealed concrete beam is the width of the cantilever steel beam + 150 mm (75 mm on each side).
[0037] In this embodiment, when multiple edge-sealed concrete beams are overlapped on both sides of the cantilever steel beam, or when the edge-sealed concrete beams on both sides of the cantilever steel beam are not in the same straight line, the outer coverage range of the reinforced concrete corbel along the longitudinal length H2 of the cantilever steel beam is the farthest distance between the two edge-sealed concrete beams H3 + 300 mm, and the outer coverage range of the reinforced concrete corbel along the span direction of the edge-sealed concrete beam H4 is the width of the cantilever steel beam + 150 mm (75 mm on each side).
[0038] In this embodiment, the length of the straight section of the upper and lower longitudinal reinforcements of the edge-sealed concrete beam and the longitudinal reinforcements of the edge-sealed concrete beam floor slab after bending is not less than 12D.
[0039] In this embodiment, a hole is opened in a certain range of the web height of the cantilever steel beam for the longitudinal reinforcement 9A at the lower part of the edge-sealed concrete beam to pass through; the transverse stiffening ribs are made of Q355C steel with the same thickness as the web of the cantilever steel beam and are connected to the cantilever steel beam using groove welds or fillet welds, and the spacing between the transverse stiffening ribs is 0.5 m.
[0040] In this embodiment, the bending bearing capacity of the cantilever steel beam is calculated according to the following formula:
[0041] Where: M —Bending moment at the end of the steel beam; γ ——Plastic development coefficient of steel beam section, 1.05 for I-section; W ——net section modulus of steel beam; f ——Bending strength coefficient of steel.
[0042] The shear bearing capacity of cantilever steel beams is calculated according to the following formula:
[0043] Where: V — shear force on the ends of the steel beam; I ——moment of inertia of the gross section of the steel beam; S ——Calculate the area moment of the gross section above (or below) the shear stress point about the neutral axis; t w ——the thickness of the web of the steel beam; fv ——Shear strength coefficient of steel.
[0044] In this embodiment, the bending bearing capacity of the normal section of the edge-sealed reinforced concrete beam is calculated according to the following formula:
[0045]
[0046] And should meet the following requirements:
[0047]
[0048] When the above conditions are not met, the following formula should be used:
[0049] Where: M u —Bending moment on the cross section of a pure reinforced concrete beam; α 1——Approximate value coefficient according to the specification; f c ——Design value of concrete axial compressive strength; f y 、 f y ’ ——Design values of tensile and compressive strength of steel bars; A s 、 A s ’ — cross-sectional area of longitudinal reinforcement in tension and compression zones; b — Cross-sectional width of edge-sealed reinforced concrete beams; h 0——Effective height of edge-sealed reinforced concrete beam section; ζ b ——height of relative limit pressure zone; a s ’ - the distance from the point of resultant force of the compressive longitudinal reinforcement to the compressive edge of the section; x ——height of the cross section of the compression zone; To ensure the rationality of the initial section, the shear section verification should be performed before calculating the shear bearing capacity of the inclined section of the edge-sealed reinforced concrete beam: 1 When h 0 / b ≤4:
[0050] 2 When h 0 / b ≥6 hours:
[0051] 3 when 4< h 0 / b When <6, it is determined by linear interpolation.
[0052] Where: V ——Design value of maximum shear bearing capacity of inclined section of reinforced concrete beam; β c ——Concrete strength influence coefficient 。
[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.
Claims
1. A junction node between a through-type edge-sealed concrete beam and a cantilevered steel beam, characterized in that: include: A cantilevered steel beam (1), an edge-sealed concrete beam (2), and a reinforced concrete corbel (3) enclosed at the junction of the two beams; The node also includes: Upper steel bars (4), lower steel bars (4A), stirrups (5) and waist bars (6) arranged within a certain height range of the reinforced concrete corbel (3); The upper steel bars (4) are arranged in the area of the reinforced concrete corbel (3) located above the upper flange of the cantilevered steel beam (1); The lower steel bars (4A) are arranged in the area of the reinforced concrete corbel (3) below the lower flange of the cantilevered steel beam (1); The stirrups (5) are arranged at intervals along the length direction of the reinforced concrete corbel (3); The waist reinforcement (6) is arranged at the edge area of the reinforced concrete corbel (3); An edge-sealed concrete beam (2) is arranged through a certain height range on one side or both sides of the reinforced concrete corbel (3).
2. The node according to claim 1, wherein: When the cantilever steel beam (1) is connected to the edge-sealed concrete beam (2) on only one side: The reinforced concrete corbel (3) has a certain height range of the cantilever steel beam (1) plus 100 mm; The upper longitudinal reinforcement (9) of the edge-sealed concrete beam (2) extends into the opposite side of the reinforced concrete corbel (3) and bends downward; The lower longitudinal reinforcement (9A) of the edge-sealed concrete beam (2) extends into the opposite side of the reinforced concrete corbel (3), passes through the web of the cantilevered steel beam (1), and then bends upward; The longitudinal reinforcement of the floor slab (7) on one side of the edge-sealed concrete beam (2) extends into the opposite side of the reinforced concrete corbel (3) and bends downward; The cantilever steel beam (1) is provided with transverse stiffening ribs (8) along the longitudinal direction.
3. The node according to claim 1, wherein: When both sides of the cantilever steel beam (1) are connected to the edge-sealed concrete beam (2): The reinforced concrete corbel (3) has a certain height range of the cantilever steel beam (1) plus 100 mm; The upper longitudinal reinforcement (9) of the edge-sealed concrete beam (2) passes through the reinforced concrete corbel (3); The lower longitudinal reinforcement (9A) of the edge-sealed concrete beam (2) passes through the reinforced concrete corbel (3) and through the web of the cantilevered steel beam (1); The longitudinal reinforcement of the floor slabs (7) on both sides passes through the reinforced concrete corbels (3).
4. The node according to claim 1, wherein: When the floor slabs (7) of the edge-sealed concrete beams (2) on both sides of the cantilevered steel beam (1) have different elevations: The upper longitudinal reinforcement (9) of the edge-sealed concrete beam (2) passes through the reinforced concrete corbel (3); The lower longitudinal reinforcement (9A) of the edge-sealed concrete beam (2) passes through the reinforced concrete corbel (3), passes through the web of the cantilevered steel beam (1), and then bends upward; The longitudinal reinforcement of the upper floor slab (7) passes through the reinforced concrete corbel (3) and bends downward; The longitudinal reinforcement of the lower floor slab (7) passes through the reinforced concrete corbel (3), passes through the web of the cantilevered steel beam (1) and then bends upward; The cantilever steel beam (1) is provided with transverse stiffening ribs (8) along the longitudinal direction.
5. The node according to any one of claims 1 to 4, characterized in that: The outer coverage range of the reinforced concrete corbel (3) along the longitudinal length of the cantilever steel beam (1) is the width of the edge-sealed concrete beam (2) plus 300 mm, and the length along the span direction of the edge-sealed concrete beam (2) is the width of the cantilever steel beam (1) plus 150 mm.
6. The node according to claim 1, wherein: When a cantilevered steel beam (1) overlaps multiple edge-sealed concrete beams (2) or the beams on both sides are not in the same straight line: The longitudinal length of the reinforced concrete corbel (3) is the distance between the two farthest edge-sealed concrete beams (2) plus 300 mm; The length in the span direction is the width of the cantilever steel beam (1) plus 150 mm.
7. The node according to claim 2 or 4, characterized in that: The straight length of the upper longitudinal reinforcement (9) and the lower longitudinal reinforcement (9A) of the edge-sealed concrete beam (2) and the longitudinal reinforcement of the floor slab (7) after bending is not less than 12 times the diameter D of the reinforcement.
8. The node according to claim 2 or 4, characterized in that: The web of the cantilevered steel beam (1) has openings for the lower longitudinal reinforcement of the edge-sealed concrete beam (2) to pass through; The transverse stiffening ribs (8) are made of Q355C and have the same thickness as the web of the cantilever steel beam (1), and are connected by groove welds or fillet welds.
9. A method for designing a node according to any one of claims 1 to 8, characterized in that: include: S1: The bending capacity of the cantilever steel beam (1) is calculated according to the following formula: Where: M —Bending moment at the end of the steel beam; γ ——Plastic development coefficient of steel beam section, 1.05 for I-section; W ——net section modulus of steel beam; f ——Bending strength coefficient of steel; S2: The shear capacity of the cantilever steel beam (1) is calculated according to the following formula: Where: V — shear force on the ends of the steel beam; I ——moment of inertia of the gross section of the steel beam; S - Calculate the area moment of the gross section above or below the shear stress about the neutral axis; t w ——the thickness of the web of the steel beam; f v ——Steel shear strength coefficient; S3: The bending bearing capacity of the normal section of the edge-sealed reinforced concrete beam (2) is calculated according to the following formula: And should meet the following requirements: When the above conditions are not met, the following formula should be used: Where: M u —Bending moment on the cross section of a pure reinforced concrete beam; α 1——Approximate value coefficient according to the specification; f c ——Design value of concrete axial compressive strength; f y 、 f y ’ ——Design values of tensile and compressive strength of steel bars; A s 、 A s ’ — cross-sectional area of longitudinal reinforcement in tension and compression zones; b — Cross-sectional width of edge-sealed reinforced concrete beams; h 0——Effective height of edge-sealed reinforced concrete beam section; ζ b ——height of relative limit pressure zone; a s ’ - the distance from the point of resultant force of the compressive longitudinal reinforcement to the compressive edge of the section; x ——Height of the cross section of the compression zone.
10. The design method according to claim 9, characterized in that: To ensure the rationality of the initial section, the shear section verification should be performed before calculating the shear bearing capacity of the inclined section of the edge-sealed reinforced concrete beam: when h 0 / b ≤4: when h 0 / b ≥6 hours: When 4< h 0 / b When <6, it is determined by linear interpolation; Where: V ——Design value of the maximum shear bearing capacity of the inclined section of edge-sealed reinforced concrete beam; β c ——Concrete strength influence coefficient.