Assembly type prestress SCCB and combination column frame connecting structure and construction technology

Abstract

The invention discloses a fabricated prestressed SCCB and combination column frame connecting structure and a construction technology, and belongs to the technical field of building construction. The frame connecting structure comprises steel reinforced concrete columns, stiff concrete-filled steel tubular columns and assembly type prestress SCCBs, the steel reinforced concrete columns are arranged on the two sides of the stiff concrete-filled steel tubular columns respectively, and the assembly type prestress SCCBs are connected between the stiff concrete-filled steel tubular columns and the steel reinforced concrete columns. The fabricated prestress SCCB on one side of the stiff concrete-filled steel tubular column is connected with the steel reinforced concrete column through an inner flange plate, and the other side of the stiff concrete-filled steel tubular column is connected with the steel reinforced concrete column through an outer flange plate; the assembly type prestress SCCB is connected with the stiff concrete-filled steel tubular column through longitudinal steel plates, and longitudinal steel bars between the assembly type prestress SCCB and the stiff concrete-filled steel tubular column are connected through straight thread sleeves. According to the method, excessive concentration of local stress is effectively avoided, weak areas of the structure during stress are reduced, safety and reliability are improved, and ductility and shock resistance of the structure are enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of building construction, and in particular relates to an assembled prestressed SCCB and combined column frame connection structure and a construction process. Background Art

[0002] With the acceleration of urbanization and the continuous development of infrastructure construction, the demand for high-rise buildings and large-span structures is increasing. Although traditional cast-in-place concrete structures have good durability and bearing capacity, they have many shortcomings in construction speed, environmental performance and cost control. Therefore, the development of new efficient, environmentally friendly and economical large-span structural systems has become one of the research hotspots in the field of civil engineering. Prefabricated construction technology is a modern construction method that improves construction speed and efficiency by prefabricating components in factories and then assembling them on site. Prefabricated construction technology has the advantages of short construction period, low labor demand and clean construction environment. It is widely used in high-rise buildings, large public buildings and large-span industrial buildings. Vigorously developing prefabricated buildings and accelerating intelligent construction technology have become the main tasks for the development of new building industrialization in my country.

[0003] While prefabricated frame structures have been widely used and promoted in the construction field, the problem of prefabricated node connection has always been a key research point in the development of prefabricated buildings. The design and construction quality control of nodes are difficult. If the node connection is not firm or has defects, it may have an adverse effect on the stability and safety of the overall structure. In order to overcome the difficulties of prefabricated node connection and improve the overall performance of prefabricated buildings, many experts and scholars in my country are committed to exploring and optimizing various connection methods. The design of prefabricated nodes requires comprehensive consideration of multiple factors such as material properties, connection form, and stress state, while the construction process requires high precision and high efficiency, which increases the difficulty of design and construction. Summary of the invention

[0004] In view of the above-mentioned technical problems, the present invention provides an assembled prestressed SCCB (Steel-encased concrete composite beam, that is, an outer steel-concrete composite beam) and a composite column frame connection structure and a construction process. Through two different node connection structures and construction processes, the overall performance of the frame structure is excellent. The tight connection at the nodes can well transmit the internal force between the upper and lower columns, effectively avoiding excessive concentration of local stress, reducing the weak areas of the structure when subjected to stress, improving the safety and reliability of the structure, and enhancing the ductility and seismic resistance of the structure. The use of outer steel-concrete and composite columns improves the fire resistance and corrosion resistance of the structure.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] The present invention discloses a prefabricated prestressed SCCB and composite column frame connection structure, comprising a steel-concrete column, a rigid steel tube concrete column and a prefabricated prestressed SCCB, wherein the SCCB is an externally-clad steel-concrete composite beam, steel-concrete columns are respectively arranged on both sides of the rigid steel tube concrete column, and the prefabricated prestressed externally-clad steel-concrete composite beam is connected between the rigid steel tube concrete column and the steel-concrete column, the prefabricated prestressed externally-clad steel-concrete composite beam on one side of the rigid steel tube concrete column is connected to the steel-concrete column through an inner flange, and the other side is connected through an outer flange; the prefabricated prestressed externally-clad steel-concrete composite beam and the rigid steel tube concrete column are both connected through longitudinal steel plates, and the longitudinal steel bars between the prefabricated prestressed externally-clad steel-concrete composite beam and the rigid steel tube concrete column are connected through straight threaded sleeves.

[0007] Furthermore, the assembled prestressed steel-concrete composite beam has a notch II and a notch I at one end connected to the inner flange and at the upper and lower end faces connected to the rigid steel tube concrete column end. After connecting the inner flange, the straight threaded sleeve and the longitudinal steel plate, concrete is poured in the notch I and the notch II.

[0008] Furthermore, an inner flange or an outer flange with bolt holes is fixed to the end of the cantilever beam of the steel concrete column.

[0009] Furthermore, one end of the prefabricated prestressed steel-clad-concrete composite beam is fixed with a holed inner flange or outer flange by pre-buried anchor bars, and the other end is provided with notches I on both sides of the upper and lower end faces, and the ends of the longitudinal reinforcements in the prefabricated prestressed steel-clad-concrete composite beam are placed in the notch I, and the upper and lower side surfaces of the prefabricated prestressed steel-clad-concrete composite beam connected to the inner flange end are provided with notches II, and concrete is poured in the notches I and II after the frame is connected.

[0010] The construction process of the assembled prestressed SCCB and the composite column frame connection structure is carried out in the following steps:

[0011] Frame assembly: first place two steel concrete columns on both sides of the rigid steel tube concrete column with a reserved prestressed channel with a notch Ⅰ at the end, and then assemble the two ends of the assembled prestressed outer steel-concrete composite beam with the steel concrete column and the rigid steel tube concrete column to form a frame structure;

[0012] Connection node: The connection end of the steel-concrete column is provided with an inner flange or an outer flange. One end of the assembled prestressed external steel-concrete composite beam is fixed with an inner flange or an outer flange with a hole by pre-buried anchor bars. The other end has notches Ⅰ on both sides of the upper and lower end faces. The end of the longitudinal steel bar of the beam is placed in notch Ⅰ. The steel-concrete column is provided with an inner flange or an outer flange. The upper and lower sides of the external steel-concrete beam connected to the inner flange end are provided with notches Ⅱ. The inner flanges or outer flanges of the two are aligned with each other, and bolts are respectively passed through the bolt holes of the two inner flanges or outer flanges, and the nuts are tightened. Concrete is poured in the notch Ⅱ to complete the connection.

[0013] The reserved prestressed tendons extending out of the assembled prestressed steel-concrete composite beam are passed through the reserved holes between the rigid steel tube concrete column and its cantilever beam, and fixed to the rigid steel tube concrete column with anchors after prestressing. The two prestressed tendons are staggered in an arc shape in the rigid steel tube concrete column. The assembled prestressed steel-concrete composite beam is tightly fitted with the cantilever beam of the rigid steel tube concrete column. The upper and lower connecting end faces are both provided with notches Ⅰ. The longitudinal steel bars between the assembled prestressed steel-concrete composite beam and the cantilever beam of the rigid steel tube concrete column in the notch Ⅰ are extended for a section and connected by a straight threaded sleeve. Longitudinal steel plates are respectively placed on the upper and lower connecting end faces of the assembled prestressed steel-concrete composite beam and the cantilever beam of the rigid steel tube concrete column. The vertical bolts embedded at the top and bottom of the connection area between the cantilever beam of the rigid steel tube concrete column and the assembled prestressed steel-concrete composite beam are passed through their bolt holes, the nuts are tightened to connect the longitudinal steel plates, and concrete is poured in the notch Ⅰ to complete the connection.

[0014] Furthermore, the prefabrication method of the steel-concrete column is to place the steel after tying the column longitudinal reinforcement and the column stirrups, fix the inner flange or outer flange with bolt holes at the end of the cantilever beam, support the formwork and pour concrete to complete the prefabrication of the steel-concrete column.

[0015] Furthermore, the prefabrication method of the assembled prestressed external steel-concrete composite beam is to embed anchor bars at the connection between the external steel-concrete composite beam and the inner / outer flange, embed prestressed bars with corrugated pipes at the bottom of the external steel-concrete composite beam, fix the inner flange or outer flange with holes by the embedded anchor bars, then tie the longitudinal steel bars and beam stirrups to form a steel skeleton, fix the external steel by welding it to the beam stirrups, support the formwork and pour concrete to form an assembled prestressed external steel-concrete composite beam with embedded prestressed bars, pass the reserved prestressed bars through the reserved channels of the prefabricated rigid steel tube concrete column, use the post-tensioning method to tension the prestressed bars and then anchor them to both sides of the rigid steel tube concrete column, the upper and lower end faces of the cantilever connection end of the prefabricated rigid steel tube concrete column are provided with notches I, the end of the longitudinal steel bars of the beam is placed in notch I, the upper and lower side faces of the internal flange end of the assembled prestressed external steel-concrete composite beam are provided with notches II, and after the frame is connected, the notches I and II are used for post-pouring concrete.

[0016] The beneficial effects of the present invention are:

[0017] 1. The present invention uses two different node connection structures and construction processes to make the overall performance of the frame structure superior. The tight connection at the node can well transmit the internal force between the upper and lower columns, effectively avoiding excessive concentration of local stress, reducing the weak area of ​​the structure when subjected to stress, improving the safety and reliability of the structure, and enhancing the ductility and seismic resistance of the structure. The ductility of the structure refers to the ability of the structure to undergo inelastic deformation without significantly reducing the bearing capacity of the structure.

[0018] 2. The use of the prestressed SCCB and the composite column of the present invention improves the fire resistance and corrosion resistance of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the framework structure of the present invention.

[0020] Figure 2 for Figure 1 Schematic diagram of the bolt connection structure of the Chinese and foreign flanges.

[0021] Figure 3 for Figure 2 Schematic diagram of the connection end structure of the prefabricated prestressed SCCB.

[0022] Figure 4 for Figure 2 Schematic diagram of section II.

[0023] Figure 5 for Figure 2 Schematic diagram of the II-II cross section.

[0024] Figure 6 for Figure 1Schematic diagram of the bolt connection structure of the inner flange.

[0025] Figure 7 for Figure 6 Schematic diagram of the connection end structure of the prefabricated prestressed SCCB.

[0026] Figure 8 for Figure 6 Schematic diagram of the III-III cross section.

[0027] Fig. 9 for Figure 1 Schematic diagram of the structure of the connection between the middle longitudinal steel plate and the straight thread sleeve.

[0028] Fig.10 for Fig. 9 Schematic diagram of the connection end structure of the prefabricated prestressed SCCB.

[0029] Fig.11 for Fig. 9 Schematic diagram of the IV-IV cross-section of a medium-strength steel tube concrete column in which the rigid steel tube is a circular steel tube.

[0030] Fig.12 for Fig. 9 Schematic diagram of the IV-IV cross section of a medium-strength steel tube concrete column in which the stiffening steel tube is a square steel tube.

[0031] In the figure: 1 post-cast concrete; 2 assembled prestressed steel-concrete composite beam; 3 prestressed tendons; 4 embedded anchor bars; 5 beam longitudinal reinforcement; 6 steel-encased steel; 7 column longitudinal reinforcement; 8 concrete; 9 inner flange; 10 outer flange; 11 column stirrups; 12 beam stirrups; 13 cantilever beam; 14 bolt hole; 15 steel-concrete column; 16 steel; 17 straight threaded sleeve; 18 rigid steel tube concrete column; 19 anchor; 20 longitudinal steel plate, 21 notch I, 22 notch II. DETAILED DESCRIPTION

[0032] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0033] Embodiment: The present invention discloses an assembled prestressed SCCB and composite column frame connection structure, comprising a steel-concrete column 15, a rigid steel tube concrete column 18 and an assembled prestressed externally-clad steel-concrete composite beam 2, wherein the steel-concrete columns 15 are respectively arranged on both sides of the rigid steel tube concrete column 18, and the assembled prestressed externally-clad steel-concrete composite beam 2 is connected between the rigid steel tube concrete column 18 and the steel-concrete column 15, and the assembled prestressed externally-clad steel-concrete composite beam 2 on one side of the rigid steel tube concrete column 18 is connected to the steel-concrete column 15 by an inner flange 9, and the other side is connected by an outer flange 10; the prefabricated prestressed externally-clad steel-concrete composite beam 2 and the rigid steel tube concrete column 18 are both connected and anchored to the prestressed steel bars 3 in the beam by longitudinal steel plates 20, and are fixed by anchors 19 after prestressing, and the longitudinal steel bars between the assembled prestressed externally-clad steel-concrete composite beam 2 and the rigid steel tube concrete column 18 are connected by straight threaded sleeves.

[0034] The assembled prestressed external steel-concrete composite beam 2 is connected to one end of the inner flange 9 and the upper and lower end faces of the cantilever end of the rigid steel tube concrete column 18 are both provided with a notch Ⅰ21 and a reserved prestressed channel. After connecting the inner flange 9, the straight threaded sleeve 17 and the longitudinal steel plate 20, and tensioning the prestress of the assembled embedded prestressed tendons 3, it is anchored by the anchor 19, and concrete 1 is poured in the notch.

[0035] An inner flange 9 or outer flange 10 with bolt holes is fixed to the end of the cantilever beam 13 of the steel concrete column 15, and is connected to the inner flange 9 or outer flange 10 on the assembled prestressed outer steel-concrete composite beam 2 by bolts.

[0036] At the end of the assembled prestressed outer steel-concrete composite beam 2, the inner flange 9 or the outer flange 10 with a hole is fixed by pre-embedded anchor bars 4, and then the longitudinal steel bars 5 and the beam stirrups 12 are tied to form a steel skeleton, and the outer steel is fixed by welding on the beam stirrups 12, and the assembled embedded prestressed tendons 3 are placed at the bottom of the assembled prestressed outer steel-concrete composite beam 2, and the formwork is supported and concrete is poured to form the assembled outer steel-concrete composite beam 2 with embedded prestressed tendons 3. A notch Ⅰ21 is reserved on both sides of the upper and lower end surfaces of the cantilever connection end of the prefabricated rigid steel tube concrete column 18, and the assembled embedded prestressed tendons 3 extend out of the notch Ⅰ21 end of the assembled prestressed outer steel-concrete composite beam 2, and the end of the longitudinal steel bars 5 of the beam is placed in the notch Ⅰ21. The upper and lower side surfaces of the assembled prestressed outer steel-concrete composite beam 2 connected to the inner flange 9 end are provided with notches Ⅱ22, and after the frame is connected, the notches Ⅰ21 and Ⅱ22 are used for post-casting concrete.

[0037] Anchor bars 4 are embedded at one end of the assembled prestressed steel-concrete composite beam 2, and prestressed bars 3 with corrugated tubes are embedded at the bottom of the assembled prestressed steel-concrete composite beam 2, and one end extends out of a reserved channel for passing through a prefabricated rigid steel tube concrete column 18, and an inner flange 9 or an outer flange 10 with a hole is fixed by the embedded anchor bars 4. The upper and lower end surfaces of the other end are provided with notches Ⅰ21 on both sides, and the prestressed bars 3 pass through the reserved channel of the prefabricated rigid steel tube concrete column 18. The prestressed bars 3 are tensioned by the post-tensioning method and then anchored to both sides of the prefabricated rigid steel tube concrete column 18 and fixed with anchors 19. The ends of the longitudinal reinforcement bars 5 in the assembled prestressed steel-concrete composite beam 2 are placed in the notch Ⅰ21, and the upper and lower side surfaces of the assembled prestressed steel-concrete composite beam 2 connected to the inner flange 9 are provided with notches Ⅱ22. After the frame is connected, concrete 1 is post-poured in the notch Ⅰ21 and the notch Ⅱ22.

[0038] The construction process of the prefabricated prestressed SCCB and combined column frame connection structure of the present invention is carried out according to the following steps:

[0039] Frame assembly: first hoist two steel concrete columns 15 and place them on both sides of the rigid steel tube concrete column 18 with notches and reserved prestressed channels at the ends, and then assemble the two ends of the assembled prestressed outer steel-concrete composite beam 2 with the steel concrete column 15 and the rigid steel tube concrete column 18 to form a frame structure;

[0040] Connect the nodes:

[0041] (1) Connect the inner and outer flanges:

[0042] The connecting end of the steel-concrete column 15 is provided with an inner flange 9 or an outer flange 10. One end of the assembled prestressed outer steel-concrete composite beam 2 is fixed with a hole inner flange 9 or an outer flange 10 by a pre-buried anchor bar 4. The other end has a notch Ⅰ 21 on both sides of the upper and lower end faces. The end of the longitudinal steel bar 5 of the beam is placed in the notch Ⅰ 21. The upper and lower side faces of the outer steel-concrete beam 2 connected to the inner flange 9 are provided with a notch Ⅱ 22. The inner flanges 9 or outer flanges 10 of the two are aligned with each other, and bolts are respectively passed through the bolt holes 14 of the two inner flanges 9 or outer flanges 10, and the nuts are tightened. Concrete 1 is poured in the notch Ⅱ 22 to complete the connection.

[0043] (2) Connecting rigid steel tube concrete columns 18:

[0044] The reserved prestressed tendons 3 extending from the assembled prestressed outer steel-concrete composite beam 2 are passed through the reserved channel between the rigid steel tube concrete column 18 and its cantilever beam, and then prestressed and fixed to the rigid steel tube concrete column 18 with anchors 19. The two prestressed tendons 3 are staggered in an arc shape in the rigid steel tube concrete column 18. The assembled prestressed outer steel-concrete composite beam 2 is tightly fitted with the cantilever beam of the rigid steel tube concrete column 18, and the upper and lower connecting end faces are both provided with a notch Ⅰ21. The assembled prestressed outer steel-concrete composite beam in the notch Ⅰ21 2 and the cantilever beam of the rigid steel tube concrete column 18 are extended out for a section and connected by a straight threaded sleeve 17. Longitudinal steel plates 20 are placed on the upper and lower connecting end faces of the assembled prestressed external steel-concrete composite beam 2 and the cantilever beam of the rigid steel tube concrete column 18 respectively. The vertical bolts embedded at the top and bottom of the connection area between the cantilever beam 13 of the rigid steel tube concrete column 18 and the assembled prestressed external steel-concrete composite beam 2 are passed through their bolt holes, and the nuts are tightened to connect the longitudinal steel plates 20. Concrete 1 is poured in the gap I 21 to complete the connection.

[0045] The prefabrication method of the steel-concrete column 15 is to tie the column longitudinal reinforcement 7 and the column stirrups 11 according to the design requirements, place the steel 16, fix the inner flange 9 or the outer flange 10 with bolt holes at the end of the cantilever beam 13, support the formwork and pour the concrete 8 to complete the prefabrication of the steel-concrete column 15.

[0046] The prefabrication method of the assembled prestressed external steel-concrete composite beam 2 is to embed and fix the prestressed tendons 3 in the beam according to the design requirements, then tie the longitudinal steel bars 5 and the beam stirrups 12 to form a steel skeleton, fix the external steel 6 by welding it to the beam stirrups 12, support the formwork, and pour concrete 8 to form the assembled prestressed external steel-concrete composite beam 2.

[0047] The components not described in detail in this application are all existing conventional technologies and will not be described in detail here.

[0048] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. An assembled prestressed SCCB and composite column frame connection structure, characterized in that: The invention comprises a steel-concrete column, a rigid steel tube concrete column and an assembled prestressed SCCB, wherein the SCCB is an outer-clad steel-concrete composite beam, steel-concrete columns are respectively arranged on both sides of the rigid steel tube concrete column, and an assembled prestressed outer-clad steel-concrete composite beam is connected between the rigid steel tube concrete column and the steel-concrete column, the assembled prestressed outer-clad steel-concrete composite beam on one side of the rigid steel tube concrete column is connected to the steel-concrete column through an inner flange, and the other side is connected through an outer flange; the assembled prestressed outer-clad steel-concrete composite beam and the rigid steel tube concrete column are both connected through longitudinal steel plates, and the longitudinal reinforcement between the assembled prestressed outer-clad steel-concrete composite beam and the rigid steel tube concrete column is connected through a straight threaded sleeve.

2. According to claim 1, the prefabricated prestressed SCCB and composite column frame connection structure is characterized in that: The assembled prestressed steel-concrete composite beam has one end connected to the inner flange and the upper and lower end faces connected to the rigid steel tube concrete column end with notches II and I. After connecting the inner flange, the straight threaded sleeve and the longitudinal steel plate, concrete is poured in notches I and II.

3. According to claim 1, the prefabricated prestressed SCCB and composite column frame connection structure is characterized in that: An inner flange or an outer flange with bolt holes is fixed at the end of the cantilever beam of the steel concrete column.

4. According to claim 1, the prefabricated prestressed SCCB and composite column frame connection structure is characterized in that: One end of the assembled prestressed steel-clad-concrete composite beam is fixed with a hole inner flange or outer flange by pre-buried anchor bars, and the other end is provided with notches I on both sides of the upper and lower end faces, and the ends of the longitudinal reinforcements in the assembled prestressed steel-clad-concrete composite beam are placed in the notch I. The upper and lower side surfaces of the assembled prestressed steel-clad-concrete composite beam connected to the inner flange end are provided with notches II, and concrete is poured in the notches I and II after the frame is connected.

5. The construction process of the prefabricated prestressed SCCB and composite column frame connection structure according to any one of claims 1 to 3 is characterized in that: Follow these steps: Frame assembly: first place two steel concrete columns on both sides of the rigid steel tube concrete column with a reserved prestressed channel with a notch Ⅰ at the end, and then assemble the two ends of the assembled prestressed outer steel-concrete composite beam with the steel concrete column and the rigid steel tube concrete column to form a frame structure; Connection node: The connection end of the steel-concrete column is provided with an inner flange or an outer flange. One end of the assembled prestressed external steel-concrete composite beam is fixed with an inner flange or an outer flange with a hole by pre-buried anchor bars. The other end has notches Ⅰ on both sides of the upper and lower end faces. The end of the longitudinal steel bar of the beam is placed in notch Ⅰ. The steel-concrete column is provided with an inner flange or an outer flange. The upper and lower sides of the external steel-concrete beam connected to the inner flange end are provided with notches Ⅱ. The inner flanges or outer flanges of the two are aligned with each other, and bolts are respectively passed through the bolt holes of the two inner flanges or outer flanges, and the nuts are tightened. Concrete is poured in the notch Ⅱ to complete the connection. The reserved prestressed tendons extending out of the assembled prestressed steel-concrete composite beam are passed through the reserved holes between the rigid steel tube concrete column and its cantilever beam, and fixed to the rigid steel tube concrete column with anchors after prestressing. The two prestressed tendons are staggered in an arc shape in the rigid steel tube concrete column. The assembled prestressed steel-concrete composite beam is tightly fitted with the cantilever beam of the rigid steel tube concrete column. The upper and lower connecting end faces are both provided with notches Ⅰ. The longitudinal steel bars between the assembled prestressed steel-concrete composite beam and the cantilever beam of the rigid steel tube concrete column in the notch Ⅰ are extended for a section and connected by a straight threaded sleeve. Longitudinal steel plates are respectively placed on the upper and lower connecting end faces of the assembled prestressed steel-concrete composite beam and the cantilever beam of the rigid steel tube concrete column. The vertical bolts embedded at the top and bottom of the connection area between the cantilever beam of the rigid steel tube concrete column and the assembled prestressed steel-concrete composite beam are passed through their bolt holes, the nuts are tightened to connect the longitudinal steel plates, and concrete is poured in the notch Ⅰ to complete the connection.

6. The construction process of the prefabricated prestressed SCCB and composite column frame connection structure according to claim 5 is characterized by: The prefabrication method of the steel-concrete column is to place the steel after tying the column longitudinal reinforcement and the column stirrups, fix the inner flange or outer flange with bolt holes at the end of the cantilever beam, support the formwork and pour concrete to complete the prefabrication of the steel-concrete column.

7. The construction process of the prefabricated prestressed SCCB and composite column frame connection structure according to claim 5 is characterized by: The prefabrication method of the assembled prestressed external steel-concrete composite beam is to embed anchor bars at the connection between the external steel-concrete composite beam and the inner / outer flange, embed prestressed bars with corrugated pipes at the bottom of the external steel-concrete composite beam, fix the inner flange or outer flange with holes by the embedded anchor bars, then tie the longitudinal steel bars and beam stirrups to form a steel skeleton, fix the external steel by welding on the beam stirrups, support the formwork and pour concrete to form an assembled prestressed external steel-concrete composite beam with embedded prestressed bars, pass the reserved prestressed bars through the reserved channels of the prefabricated rigid steel tube concrete column, use the post-tensioning method to tension the prestressed bars and then anchor them to both sides of the rigid steel tube concrete column, the upper and lower end faces of the cantilever connection end of the prefabricated rigid steel tube concrete column are provided with notches I, the end of the longitudinal steel bars of the beam is placed in the notch I, the upper and lower side faces of the internal flange end of the assembled prestressed external steel-concrete composite beam are provided with notches II, and the notches I and II are used for post-pouring concrete after the frame is connected.

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