Fabricated prestressed steel-concrete composite structure system

Abstract

The invention discloses a fabricated prestressed steel-concrete composite structure system which comprises n vertical bearing columns, m rectangular column net units defined by four vertical bearing columns are formed on a horizontal building surface, and i elevation levels are distributed in the height direction of a building. All the column net units are provided with beam slab modules with the same height at the same elevation level, and each module comprises prestressed superposed beams arranged along the four sides of the rectangular column net units and light composite floor slabs which are laid on the prestressed superposed beams on the same layer and are integrated with heat preservation layers; the prestressed superposed beam is connected with the vertical load-bearing column in a bolt-welding mixed mode through the first profile steel connecting piece and the second profile steel connecting piece. Aiming at the problems of an existing fabricated concrete frame structure system, in node connection, through unique design of first and second profile steel connecting pieces and bolting and welding mixed connection, beam end rigidity is in smooth transition, brittle failure under strong shock is avoided, node ductile deformation and energy dissipation performance are improved, and the anti-seismic requirement is met.

Description

Technical Field

[0001] This invention relates to the technical field of prefabricated concrete frame structures and steel-concrete composite structures, and particularly to a prefabricated prestressed steel-concrete composite structure system. Background Technology

[0002] In the field of architectural engineering design and construction, the selection and optimization of structural systems play a decisive role in the overall performance of buildings, life-cycle cost control, and construction organization efficiency. While traditional cast-in-place concrete structural systems possess inherent advantages such as strong structural integrity and good seismic performance, they also have drawbacks including relatively long construction cycles, numerous on-site wet work procedures, and a large amount of construction waste, causing significant pollution to the urban environment. With the accelerated advancement of building industrialization and the popularization of green building concepts, prefabricated buildings, with their significant advantages such as factory prefabrication, on-site assembly construction, strong quality control, and high environmental friendliness, are gradually becoming an important development direction for the transformation and upgrading of the construction industry.

[0003] As one of the main structural forms of prefabricated buildings, the prefabricated concrete frame structure system typically uses cast-in-place or precast concrete columns as vertical load-bearing members, combined with precast concrete composite beams as horizontal load-bearing members, forming a spatial load-bearing system through reliable connections between the beams and vertical load-bearing columns. However, after extensive engineering practice, existing prefabricated concrete frame structure systems still face several technical challenges that urgently need to be addressed: 1. Weak node connections are a prominent issue: Traditional prefabricated structural beams and vertical load-bearing columns often use mechanical connection methods such as sleeve grouting connection or high-strength bolt connection. These connection structures are prone to brittle failure under strong earthquakes, making it difficult to meet the seismic design requirements of "strong nodes and weak components".

[0004] 2. Bottlenecks in improving construction efficiency: Due to the traditional "layer-by-layer construction" organizational model, there is an unavoidable waiting time between each process, making it difficult to achieve a breakthrough in construction progress.

[0005] 3. Cracking control faces technical challenges: When using ordinary floor slab components, the slab thickness must be increased to meet deformation control requirements when the span exceeds 6m. This not only leads to a significant increase in the self-weight of the structure, but also causes material waste.

[0006] 4. Inherent defects in thermal performance: Conventional composite floor slab construction requires on-site pouring of the upper layer of concrete. This construction process makes it difficult to achieve overall integration of the insulation layer, affecting the thermal performance of the building envelope. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a prefabricated prestressed steel-concrete composite structural system to solve many issues associated with existing prefabricated concrete frame structures. In terms of node connections, a unique design and hybrid bolted-welded connection of the first and second type steel connectors ensures a smooth transition of beam end stiffness, avoiding brittle failure under strong earthquakes, improving node ductility and energy dissipation performance, and meeting seismic design requirements. Regarding construction efficiency, a modular three-dimensional flow-line operation is adopted. After the entire column is constructed, rectangular column grid units are divided. Through simultaneous layer-by-layer and cross-layer process coupling, waiting time for processes is reduced, construction progress is improved, and the bottleneck of traditional "layer-by-layer construction" is overcome. For crack control, a lightweight composite floor slab with integrated insulation is used. Compared to ordinary concrete floor slabs, it does not require excessive increases in slab thickness to meet deformation control requirements, avoiding increased structural weight and material waste. In terms of thermal performance, the lightweight composite floor slab with integrated insulation avoids the problem of difficult overall integration of the insulation layer caused by on-site pouring of the upper concrete layer in conventional composite floor slabs, thus improving the thermal performance of the building envelope.

[0008] To achieve the above objectives, this invention discloses a prefabricated prestressed steel-concrete composite structure system, comprising n vertical load-bearing columns. The key feature is that the n vertical load-bearing columns form m rectangular column grid units on the horizontal building surface. Each rectangular column grid unit is enclosed by four vertical load-bearing columns and distributed across i elevation levels along the building height direction. All column grid units have beam-slab modules of the same height at the same building elevation level. The beam-slab modules include prestressed composite beams arranged along the four sides of the rectangular column grid unit. The prestressed composite beam is laid on the same layer of prestressed composite beam and has an integrated insulation layer. The prestressed composite beam is connected to the vertical load-bearing column by means of a first steel connector and a second steel connector. The first steel connector creates a transition area in the beam body of the prestressed composite beam with a continuous and stable change in bending stiffness. Node concrete is also poured between the vertical load-bearing column, the prestressed composite beam and the lightweight composite floor slab. Wherein: n=4m, m>i≥2, and m and i are positive integers.

[0009] Furthermore, modular 3D flow operations are performed according to the following rules: S1. Full column construction: On the horizontal building surface, n vertical load-bearing columns are hoisted and positioned according to the construction drawings; S2. Rectangular column grid unit division: The horizontal building plan is divided into m rectangular column grid units by n vertical load-bearing columns; S3. Progressive construction on the same floor: For the j-1 level, execute the following when construction reaches the first matrix column grid unit: Installation of the prestressed composite beam of the first beam-slab module; For the j-1 level, the following should be executed simultaneously during construction of the second matrix column grid unit: Installation of lightweight composite floor slabs for the first beam-slab module; Installation of the prestressed composite beam of the second beam-slab module; For the j-1 level, the following steps are executed simultaneously when construction reaches the a-th matrix column grid unit: Concrete pouring at the nodes of beam-slab module a-2; Installation of lightweight composite floor slab for beam-slab module a-1; Installation of the prestressed composite beam of beam module a; S4. Cross-layer process coupling: Construction at level j will commence when the following conditions are met: Beam installation trigger: After the installation of the prestressed composite beam of the m-th beam-slab module in the j-1 level is completed, if the joint concrete strength of the 1st beam-slab module in the j-1 level reaches the preset threshold, the installation of the prestressed composite beam of the 1st beam-slab module in the j-1 level will be initiated. Pouring Synchronization Trigger: When the m-th unit node at the j-1 level is being poured, the following will be executed synchronously: Installation of the lightweight composite floor slab for the first beam-slab module of the j-th elevation level; Installation of the prestressed composite beam of the second beam-slab module at the j-th elevation level; For the j-th elevation level, the following steps are executed simultaneously when construction reaches the a-th matrix grid unit: Concrete pouring at the nodes of beam-slab module a-2; Installation of lightweight composite floor slab for beam-slab module a-1; Installation of the prestressed composite beam of beam module a; S5: Final finishing touches: Synchronous execution occurs when j=i and a=m: Concrete pouring for the nodes of the (m-1)th beam-slab module; Installation of lightweight composite floor slabs for the m-th beam-slab module; Immediately after the lightweight composite floor slab installation of the m-th beam-slab module is completed, the concrete pouring of the m-th beam-slab module node is carried out. Where: j is the current construction elevation level number: j=2,3...i; 'a' represents the current construction unit number: a = 3, 4, ... m.

[0010] Furthermore, the first type of steel connector includes a pair of non-continuous embedded prestressed composite beam ends, first flange plates that support the upper and lower longitudinal reinforcements thereon, and a first web plate disposed between the two; a section of the first web plate embedded in the prestressed composite beam ends extends toward the mid-span of the beam and forms an extension section with a gradually decreasing cross-sectional height; this extension section is used to construct a transition region in the beam body where the bending stiffness changes continuously and smoothly.

[0011] Furthermore, at least a portion of the cross-sectional height of the extension exhibits a linear or non-linear variation.

[0012] Furthermore, the overall cross-sectional height of the extension section varies linearly, with its upper and lower edges extending obliquely and converging relatively to form a wedge-shaped structure.

[0013] Furthermore, the second type of steel connector includes a pair of transverse stiffening plates with grouting holes disposed in the steel sleeve of the vertical load-bearing column node, and a second web plate disposed between the two; the second web plate extends horizontally out of the node steel sleeve and is aligned and connected with the first web plate; at the upper and lower edges of the section of the second web plate extending out of the node steel sleeve, second flange plates for receiving the node steel sleeve are respectively provided; the upper and lower second flange plates are aligned and connected with the upper and lower first flange plates respectively.

[0014] Furthermore, the first steel connector and the prestressed composite beam are constructed according to the following steps: A1: Determine the embedding depth, flange stopping position, web extension length, and gradient slope of the first type of steel connector according to construction requirements; A2: In the prefabrication plant, the first flange plate and the first web plate are welded according to the construction requirements, and the extension section of the first web plate is cut and processed to form a transition zone with a gradually decreasing cross-sectional height. A3: Insert the first flange plate and the first web plate into place; A4: Weld an upper steel plate to each upper longitudinal reinforcement of the prestressed composite beam, and weld a lower steel plate to each lower longitudinal reinforcement of the prestressed composite beam. A5: The lower steel plate with the lower longitudinal ribs already welded is vertically welded to the first flange plate at the bottom of the first steel connector to form a continuous fillet weld; the upper steel plate with the upper longitudinal ribs already welded is vertically welded to the first flange plate at the top to form a continuous fillet weld. A6: Arrange high-strength prestressed steel wire bundles at the bottom of the prestressed composite beam, and tension and temporarily anchor them according to the pre-tensioning process; A7: Erect end formwork and side formwork to enclose and form the pouring cavity for the prestressed composite beam concrete. A8: Arrange stirrups and other structural reinforcement bars to build the steel reinforcement skeleton of the prestressed composite beam; A9: Pour the concrete for the prestressed composite beam and cure it to the specified strength; A10: After the concrete of the beam reaches the specified strength, the pre-tensioned high-strength prestressed steel bar bundles are released so that the prestress can be transferred to the concrete of the beam through the bond force.

[0015] Furthermore, in step A8, the spacing of the stirrups tied in the embedded part of the first steel connector is smaller than the spacing of the stirrups in other parts; a through groove is also reserved on a section of the plate at the end of the first web embedded in the prestressed composite beam, which is used to arrange tie bars through the web reinforcement of the prestressed composite beam.

[0016] Furthermore, the second type of steel connector and the vertical load-bearing column are constructed according to the following steps: B1: Fabricate the node steel sleeves of the vertical load-bearing columns in the prefabrication plant, and determine the position and extension length of the second type of steel connectors embedded in the column; B2: Weld two transverse stiffening plates at precise positions on the inner wall of the node steel sleeve. Grouting holes are reserved on the transverse stiffening plates. B3: Ensure that the second flange plates of the upper and lower sections of the second steel connector are aligned with the upper and lower transverse stiffening plates respectively, and then insert the second web plate of the second steel connector between the two transverse stiffening plates through the slot opened on the wall of the node steel sleeve. B4: The section of the second web extending to the node steel sleeve is fully penetrated and bevel-welded to the inner wall of the node steel sleeve and the two transverse stiffening plates; the second flange is continuously filled-in welded to the outer wall of the node steel sleeve. B5: Weld the node steel sleeve to all segment steel pipes as one unit to form the column body restraint steel pipe of the vertical load-bearing column; B6: Hoist and position the column restraint steel pipe, pour column concrete inside the column restraint steel pipe, and ensure that the grouting holes of the transverse stiffening plate are filled tightly.

[0017] Furthermore, the prestressed composite beam is installed according to the following steps: C1: When hoisting the prestressed composite beam, roughly align the first steel connector extending outward from the end of the prestressed composite beam with the second steel connector extending outward from the vertical load-bearing column. The first web of the first steel connector and the second web of the second steel connector are both reserved with fixing holes in their exposed parts. C2: First, use mounting bolts or some high-strength bolts in conjunction with connecting plates to temporarily fix the first and second web plates, and adjust the position and elevation of the prestressed composite beam to the design position; C3: Replace the mounting bolts with high-strength bolts, and perform initial and final tightening according to design requirements to complete the shear connection between the first and second web plates; C4: The butt joints of the upper and lower first flange plates and the second flange plates are welded on site to complete the bending connection; C5: Perform necessary anti-corrosion and fireproofing treatment on the node area.

[0018] Compared with the prior art, the significant advantages of the present invention are: (1) In terms of node connection, the unique design of the first type of steel connector and the second type of steel connector and the bolted and welded hybrid connection method make the beam end stiffness transition smoothly, avoid the problem that traditional connection structure is prone to brittle failure under strong earthquake action, improve the ductility deformation and energy dissipation performance of the node, and meet the seismic design requirements of "strong node and weak component". (2) In terms of construction efficiency, the modular three-dimensional flow operation rules are adopted. After the construction of the entire column, the rectangular column grid unit is divided. Then, through the same-layer progressive construction and cross-layer process coupling, the process is closely connected, reducing the waiting time between processes, greatly improving the construction progress, and breaking through the bottleneck of the traditional "layer-by-layer construction" organization mode. (3) For crack control, the system uses lightweight composite floor slabs with integrated insulation layers. Compared with ordinary floor slabs, lightweight composite floor slabs do not require excessive increases in slab thickness to meet the same deformation control requirements, thus avoiding the problems of significantly increased structural self-weight and material waste. In terms of thermal performance, since the lightweight composite floor slabs integrate insulation layers, the problem of difficulty in the overall integration of insulation layers caused by the need for on-site pouring of upper concrete in conventional composite floor slab construction is avoided, effectively improving the thermal performance of the building envelope; (4) In terms of the selection of connectors, after the first steel connector is embedded into the end of the prestressed composite beam at a predetermined depth, its flange stops penetrating, while the web continues to extend a distance towards the mid-span of the beam. In the extended section, its cross-sectional height gradually decreases in a linear or nonlinear manner, eventually forming a small residual cross-sectional height. This design constructs a stiffness buffer / transition zone, the core objective of which is to achieve a continuous and smooth transition of the bending stiffness of the prestressed composite beam cross-sectional height from the pure concrete area to the area containing the complete steel section, avoiding stress concentration caused by abrupt changes and delaying crack propagation. In this area, cracks in the beam concrete appear later and are more dispersed and finer, which is conducive to maintaining the contribution of concrete and making the overall stiffness degradation more gradual. At the same time, this design can also improve hysteresis performance. A smoother stiffness change and reduced stress concentration help to obtain a fuller hysteresis curve with less pinching effect, which means that the structure has a stronger energy dissipation capacity and a smaller degree of stiffness / strength degradation; (5) In the structural design of the prestressed composite beam, the first type of steel connector adopts a non-continuous design, which not only simplifies the overall structure of the prestressed composite beam, but also avoids the complexity brought about by the continuous arrangement of steel along the beam in the traditional design. This design not only greatly reduces the amount of steel used and lowers the cost, but also makes the assembly and welding work in the construction process simpler and more efficient. At the same time, due to the simple and clear structure of the first type of steel connector, the error and uncertainty in the construction process are greatly reduced, and the reliability of the node and the safety of the overall structure are improved. On the other hand, the present invention uses the first flange plate to bear the stress of the longitudinal reinforcement of the prestressed composite beam, which simplifies the detailed design of the end of the prestressed composite beam and reduces the cumbersome construction of dense openings or complex bending of the steel bars on the first flange plate. This simple structural design not only reduces the construction difficulty and improves the construction efficiency, but also reduces the potential reliability hazards of the node caused by construction quality problems. In addition, the through groove reserved on the first web plate provides convenience for the through arrangement of tie bars, further enhancing the connection performance of the node; (6) In addition, the present invention further optimizes the bolted-welded connection design to ensure the reliability and efficiency of the connection method. The connection between the first type of steel connector and the prestressed composite beam and the second type of steel connector adopts a strategy combining multiple fixing methods. On the one hand, the first flange plate of the first type of steel connector is welded and fixed to the longitudinal reinforcement of the prestressed composite beam with the help of steel pads. This rigid connection method can provide a stable force transmission path and ensure the integrity and coordination of the structure under stress. On the other hand, fixing holes are opened in the exposed parts of the first web and the second web for installing high-strength bolts. This bolt connection method not only facilitates quick on-site installation, positioning and error adjustment, but also has the ability to slip and deform, which can dissipate some seismic energy and meet the seismic performance requirements. In addition, the first flange plate and the second flange plate are aligned and welded after the bolts are tightened to ensure the tightness of the connection and the final stiffness; (7) Regarding the introduction of prestress, this invention applies prestress to the concrete of the beam by pre-tensioning high-strength prestressed steel wire bundles, effectively enhancing the load-bearing capacity and crack resistance of the entire prestressed composite beam. The prestressed steel wire bundles ensure that the concrete beam is uniformly stressed after the application of prestress, thereby improving the overall stability and durability of the structure. In addition, the application of prestressing technology further optimizes the mechanical properties of the prestressed composite beam, enabling it to better adapt to various complex working conditions and extreme load conditions; (8) Regarding the vertical load-bearing columns, a method of welding the transverse stiffening plates to the extension of the second web plate is adopted: two transverse stiffening plates with grouting holes are installed inside the node steel sleeve, with the same height as the upper and lower second flange plates. The extension of the second web plate is welded to the inner wall of the node steel sleeve and to these two transverse stiffening plates. This method provides strong bending, shear and pull-out anchorage for the extended steel section, ensuring that the bending moment and shear force of the prestressed composite beam can be effectively transferred to the core area of ​​the column. This method significantly enhances the integrity, stiffness and bearing capacity of the core area of ​​the vertical load-bearing column. The transverse stiffening plates play a restraining role on the concrete of the core column, improving its strength and deformation capacity. The grouting holes on the transverse stiffening plates can ensure that the concrete in the core area of ​​the node is poured densely and avoid voids. (9) Regarding the prefabrication and construction of beams and columns, a scientific and reasonable procedure is strictly followed, with clear quality control and technical requirements set at each stage to ensure the construction quality and performance of the entire connection node. In the construction of prestressed composite beams, each step is closely linked. From determining the geometric parameters of the first type of steel connector to welding, embedding, arranging reinforcement, pouring concrete, and applying prestress, all have been verified through practice. In terms of reinforcement arrangement, the spacing of stirrups in different parts is reasonably adjusted, and through slots are reserved on the first web for passing through tie bars, which further enhances the connection performance and overall stability of the node. In the construction of vertical load-bearing columns, from the fabrication of node steel sleeves in the prefabrication plant to determining the position and extension length of the second type of steel connector, and then to welding, hoisting, and pouring concrete, the rigor and standardization of the construction are demonstrated. In particular, during the installation of the second type of steel connector, the positioning and welding process ensures that it can provide reliable anchorage for the transmission of bending moment and shear force of the prestressed composite beam, while enhancing the integrity, stiffness, and bearing capacity of the core area of ​​the vertical load-bearing column. In the on-site connection of prestressed composite beams and vertical load-bearing columns, temporary fixing is first performed to adjust the position and elevation. Then, high-strength bolts are used to complete the shear connection, followed by welding and anti-corrosion and fireproofing treatment. This reasonable connection procedure can adapt to complex stress conditions and ensure the stability and durability of the connection. In addition, effective quality control can be implemented at each stage of the construction process, thereby ensuring the reliability of the joints and the safety of the overall structure. Attached Figure Description

[0019] 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.

[0020] Figure 1This is a schematic diagram of the matrix column grid unit structure of the combined structural system in Embodiment 1; Figure 2 This is a schematic diagram of the modular construction process of the combined structural system in Example 1; Figure 3 This is a structural schematic diagram (I) of the beam-column connection node in Embodiment 1; Figure 4 This is a structural schematic diagram (II) of the beam-column connection node in Embodiment 1; Figure 5 This is a schematic diagram of the assembly relationship between the first steel connector and the second steel connector in Embodiment 1; Figure 6 This is a schematic diagram of the steel reinforcement skeleton structure of the prestressed composite beam in Example 1; Figure 7 This is a schematic diagram of the end structure of the prestressed composite beam in Example 1 (I); Figure 8 This is a schematic diagram of the end structure of the prestressed composite beam in Example 1 (II); Figure 9 This is a schematic diagram of the end structure of the prestressed composite beam in Example 1 (III); Numbering in the diagram: 1-First type of steel connector, 2-Prestressed composite beam, 3-Second type of steel connector, 4-Vertical load-bearing column, 5-Connecting plate, 6-High-strength bolt, 7-Lightweight composite floor slab; 101-First flange plate, 102-First web plate, 103-Extension section, 104-Upper steel pad plate, 105-Lower steel pad plate, 106-Waist steel pad plate, 107-Beam end steel plate, 108-Through groove; 201-Longitudinal reinforcement, 202-Prestressed steel reinforcement bundle, 203-Waist reinforcement, 204-Stirrups, 205-Tie reinforcement, 206-Beam concrete; 301-Transverse stiffening plate, 302-Second web plate, 303-Second flange plate; 401-Node steel sleeve. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0022] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0023] Figure 1 The first embodiment of the present invention is shown: a prefabricated prestressed steel-concrete composite structure system, comprising n vertical load-bearing columns 4, characterized in that: the n vertical load-bearing columns 4 form m rectangular column grid units on the horizontal building surface, each rectangular column grid unit is enclosed by 4 vertical load-bearing columns 4, and is distributed at i elevation levels along the building height direction; all column grid units are provided with beam-slab modules of the same height at the same building elevation level; the beam-slab modules include prestressed composite beams 2 arranged along the four sides of the rectangular column grid unit, and A lightweight composite floor slab 7, with an integrated insulation layer, is laid on the same-layer prestressed composite beam 2. The prestressed composite beam is connected to the vertical load-bearing column 4 by bolting and welding through a first steel connector 1 and a second steel connector 3. The first steel connector 1 creates a transition area in the beam body of the prestressed composite beam 2 with a continuous and stable change in bending stiffness. Node concrete is also poured between the vertical load-bearing column 4, the prestressed composite beam 2, and the lightweight composite floor slab 7. Wherein: n=4m, m>i≥2, and m and i are positive integers.

[0024] Please see Figure 2 In practice, the modular three-dimensional assembly line operation shall be carried out according to the following rules: S1. Full column construction: On the horizontal building surface, the n vertical load-bearing columns are hoisted and positioned according to the construction drawings; S2. Rectangular column grid unit division: The horizontal building plan is divided into m rectangular column grid units by n vertical load-bearing columns 4; S3. Progressive construction on the same floor: For the j-1 level, execute the following when construction reaches the first matrix column grid unit: Installation of the prestressed composite beam 2 of the first beam-slab module; For the j-1 level, the following should be executed simultaneously during construction of the second matrix column grid unit: Installation of the lightweight composite floor slab 7 of the first beam-slab module; Installation of the prestressed composite beam 2 of the second beam-slab module; For the j-1 level, the following steps are executed simultaneously when construction reaches the a-th matrix column grid unit: Concrete pouring at the nodes of beam-slab module a-2; Installation of lightweight composite floor slab 7 of beam-slab module a-1; Installation of prestressed composite beam 2 of beam-slab module a; S4. Cross-layer process coupling: Construction at level j will commence when the following conditions are met: Beam installation trigger: After the installation of the prestressed composite beam of the m-th beam-slab module in the j-1 level is completed, if the joint concrete strength of the 1st beam-slab module in the j-1 level reaches the preset threshold, the installation of the 2nd prestressed composite beam of the 1st beam-slab module in the j-1 level will be initiated; Pouring Synchronization Trigger: When the m-th unit node at the j-1 level is being poured, the following will be executed synchronously: Installation of the lightweight composite floor slab 7 of the first beam-slab module of the j-th elevation level; Installation of prestressed composite beam 2 of the second beam-slab module in the j-th elevation level; For the j-th elevation level, the following steps are executed simultaneously when construction reaches the a-th matrix grid unit: Concrete pouring at the nodes of beam-slab module a-2; Installation of lightweight composite floor slab 7 of beam-slab module a-1; Installation of prestressed composite beam 2 of beam-slab module a; S5: Final finishing touches: Synchronous execution occurs when j=i and a=m: Concrete pouring for the nodes of the (m-1)th beam-slab module; Installation of the lightweight composite floor slab 7 of the m-th beam-slab module; Immediately after the installation of the lightweight composite floor slab 7 in the m-th beam-slab module is completed, the concrete pouring of the m-th beam-slab module node is carried out. Where: j is the current construction elevation level number: j=2,3...i; 'a' represents the current construction unit number: a = 3, 4, ... m.

[0025] This modular, three-dimensional, continuous construction method makes the entire construction process of the prefabricated prestressed steel-concrete composite structure system more orderly and efficient. By rationally arranging the time and sequence of each construction procedure, time and space resources are fully utilized, reducing idle and waiting time during construction and greatly improving construction efficiency. At the same time, modular construction allows for a more rational arrangement of personnel and equipment on the construction site, reducing safety hazards caused by overlapping operations.

[0026] like Figures 3 to 5As shown, in this embodiment, the first steel connector 1 includes a pair of non-continuous embedded prestressed composite beam 2 ends, first flange plates 101 that support the upper and lower longitudinal reinforcements 201, and a first web plate 102 disposed between the two; a section of the first web plate 102 embedded in the end of the prestressed composite beam 2 extends toward the mid-span of the beam and forms an extension section 103 with a gradually decreasing cross-sectional height; the extension section 103 is used to construct a transition region in the beam body with a continuous and stable change in bending stiffness.

[0027] In practical applications, at least a portion of the cross-sectional height of the extension segment 103 varies linearly or non-linearly. In this embodiment, preferably, the overall cross-sectional height of the transition segment varies linearly, with its upper and lower edges extending obliquely and converging to form a wedge-shaped structure. This wedge-shaped structure design further enhances the smoothness of the transition region, making the change in bending stiffness more uniform, thereby further optimizing the seismic performance of the structure. In other embodiments, the overall cross-sectional height of the transition segment may also vary non-linearly, or a combination of linear and non-linear variations may be used to meet specific engineering requirements or optimize structural performance. Furthermore, using a cross-sectional height design with non-linear variations, or a combination of non-linear and linear variations, may involve more complex geometries and manufacturing processes. However, in some cases, this design can provide superior performance compared to linear variations. For example, under certain specific dynamic response or load conditions, it can more effectively disperse stress and energy.

[0028] In this embodiment, the second type of steel connector 3 includes a pair of transverse stiffening plates 301 with grouting holes disposed in the node steel sleeve 401 of the vertical load-bearing column 4, and a second web plate 302 disposed between the two; the second web plate 302 extends horizontally out of the node steel sleeve 401 and is aligned and connected with the first web plate 102; at the upper and lower edges of the section of the second web plate 302 extending out of the node steel sleeve 401, second flange plates 303 for receiving the node steel sleeve 401 are also respectively provided; the upper and lower second flange plates 303 are aligned and connected with the upper and lower first flange plates 101 respectively.

[0029] Please see Figures 6 to 9 In specific implementation, the first steel connector 1 and the prestressed composite beam 2 are constructed according to the following steps: A1: Determine the embedding depth, flange stopping position, web extension length, and gradient slope of the first type of steel connector 1 according to the construction requirements; A2: At the prefabrication plant or construction site, weld the first flange plate 101 and the first web plate 102 according to the construction requirements, and cut and process the extension section 103 of the first web plate 102 to form a transition zone with a gradually decreasing cross-sectional height. A3: Insert the first flange plate 101 and the first web plate 102 into place; A4: Weld an upper steel plate 104 at each upper longitudinal reinforcement 201 of the prestressed composite beam 2, and weld a lower steel plate 105 at each lower longitudinal reinforcement 201 of the prestressed composite beam 2. A5: The lower steel plate 105, which has been welded to the lower longitudinal rib 201, is vertically welded to the first flange plate 101 at the lower part of the first steel connector 1 to form a continuous fillet weld; the upper steel plate 104, which has been welded to the upper longitudinal rib 201, is vertically welded to the upper first flange plate 101 to form a continuous fillet weld. A6: Arrange high-strength prestressed steel wire bundles 202 at the bottom of the prestressed composite beam 2, and tension and temporarily anchor them according to the pre-tensioning process. A7: Erect end formwork and side formwork to enclose and form the pouring cavity for the prestressed composite beam 2 concrete 206; A8: Arrange stirrups 204 and other structural steel bars to build the steel reinforcement cage of prestressed composite beam 2; A9: Pour the prestressed composite beam 206 concrete and cure it to the specified strength; A10: After the beam concrete 206 reaches the specified strength, the pre-tensioned high-strength prestressed steel bar bundle 202 is released so that it can transfer the prestress to the beam concrete 206 through the bond force.

[0030] During construction, the quality of each step must be strictly controlled. In step A1, when determining various dimensional parameters, precise engineering calculations and actual site conditions must be combined to ensure that the first steel connector 1 can perfectly fit the prestressed composite beam 2. In step A2, during welding and cutting, welding quality must be guaranteed to avoid problems such as incomplete welding and missing welding. The surface of the transition zone after cutting should be flat and smooth to ensure its mechanical properties. In step A3, when embedding the first flange plate 101 and the first web plate 102, professional hoisting equipment and positioning tools must be used to ensure accurate embedding position and control the deviation within a very small range. In steps A4 and A5, when welding the steel pads, the welding process requirements must be strictly followed, and the welding current, voltage, and welding speed must be controlled to ensure the strength and quality of the weld. For the arrangement of the high-strength prestressed steel bar bundle 202 in step A6, its position must be accurate and its arrangement must be neat. Tensioning and temporary anchoring must be carried out according to the standard process of pre-tensioning, and the magnitude and uniformity of the tension force must be precisely controlled. When setting up the formwork in step A7, the formwork must be installed firmly and level to prevent deformation or grout leakage during concrete pouring. In step A8, when arranging the stirrups 204 and other structural reinforcement, ensure that the spacing, quantity, and binding quality of the reinforcement meet design requirements to build a stable prestressed composite beam 2 reinforcement skeleton. In step A9, when pouring the prestressed composite beam 2 concrete 206, use layered pouring and vibration compaction to ensure the concrete's density and integrity. During concrete curing, take appropriate curing measures based on ambient temperature and humidity to ensure the concrete reaches the specified strength. In step A10, when releasing the pre-tensioned high-strength prestressed steel reinforcement bundles 202, operate slowly and evenly to avoid excessive prestress loss or cracks in the beam concrete 206 due to excessively fast release speed. Simultaneously, throughout the entire construction process, professional quality inspection personnel should conduct strict quality inspection and acceptance at each step to ensure that the construction quality of the connection nodes meets design and specification requirements.

[0031] In a specific application, in step A1, the first flange plate 101 of the first steel connector 1 is located at a distance from the end face of the prestressed composite beam 2. The insertion stops at the point where it stops; the first web 102 continues to extend its length. The extension segment 103 forms a gradient slope at both the upper and lower edges. The transition region, whose geometric parameters satisfy the relation （Ⅰ） :

[0032] In the formula: The net span of the prestressed composite beam 2; The distance between the end of the first flange plate 101 and the end of the prestressed composite beam 2; Extension segment 103 length; The total length from the end of the prestressed composite beam 2 to the end of the extension 103; Extension 103 starting height; Total height of section 2 of the prestressed composite beam; Distance from the wing edge stopping position Web height at the location; The remaining cross-sectional height at the end of extension 103; The web extension coordinates are positively directed towards the mid-span of the beam, with the origin located at the position where the first flange plate 101 stops embedding. The extended segment has a gradually changing slope of 103. The ratio of the extension length of extension segment 103 to the first flange insertion stop position; The ratio of the minimum embedment depth of the first flange plate 101 to its span; The ratio of the residual height of extension segment 103 to the initial height of the web; The ratio of the residual height of extension section 103 to the height of prestressed composite beam 2; Span utilization coefficient ; Gradual slope adjustment factor for load response; Regarding uniformly distributed loads A monotonically increasing function; Design value of maximum bending moment at mid-span of prestressed composite beam; steel yield strength; Design value of uniformly distributed load on beam.

[0033] The application of the aforementioned geometric parameter relationships is of great significance in practical engineering. When determining these parameters, it is necessary to comprehensively consider factors such as the net span of the prestressed composite beam 2 and the design value of the uniformly distributed load it bears. By calculating and applying these relationships, reasonable geometric parameters can be accurately determined for the first steel connector 1, thereby ensuring that it performs optimally in the beam structure.

[0034] For example, when the clear span of the prestressed composite beam 2 is large or the design value of the uniformly distributed load it bears is high, it is necessary to appropriately increase the embedment depth of the first flange plate 101 and the length of the extension section 103 according to the relationship to ensure that the prestressed composite beam 2 has sufficient bending resistance and stability. At the same time, the adjustment of the gradual slope also needs to be accurately calculated according to the actual situation to ensure that the change in bending stiffness in the transition area meets the design requirements.

[0035] Taking the standard floor frame beam of a high-rise office building as an example, the relationship is... （Ⅰ） Verification required: 1. Design input parameters: Prestressed composite beam 2 clear span (Structural axis spacing minus support width); Prestressed composite beam section height 2 (Dimensions indicated on the structural construction drawings); Uniformly distributed load design value (Including the combined values ​​of dead load and live load); Maximum bending moment at mid-span (Calculation results from structural analysis software); steel yield strength (Measured values ​​using Q390 grade steel); Extension 103 starting height (Specifications of HN550×200 steel section).

[0036] 2. Explanation of coefficient values:

[0037] 3. Parameter calculation process: (1) Determine the stopping position of the first flange plate 101 : ; Values: ; Note: Meets seismic anchorage requirements Satisfying moment transfer ; (2) Determine the web extension length : ; Note: Coefficient Achieve efficient transition of short extension segment 103; (3) Determine the total length from the end of the prestressed composite beam 2 to the end of the extension section 103. : ; Validation constraints: ; (4) Determine the stiffness adjustment coefficient : ; Note: Logarithmic function response to load intensity, Corresponding to a moderately gradual slope; (5) Determine the unilateral cutting slope : ; Note: Slope is positively correlated with load. It is inversely correlated with span; (6) Determine the web height function : ; Key points: ; ; (7) Determine the height of the residual section : ; Validation constraints: ; (8) Total length of steel section : ; The prestressed composite beam 2 extends 200mm outward at its end for connection to the vertical load-bearing column 4. .

[0038] 4. Cutting rules for extension segment 103: Cutting line on the top edge of the plate: ; Cutting line on the bottom edge: .

[0039] 5. Construction and Zoning of Prestressed Composite Beam 2: |← Left section steel-covered area→|← Middle concrete area→|← Right section steel-covered area→| 0 ────────3055mm ─────── 4945mm ───────8000mm; The complete area of ​​the first flange plate 101 and the first web plate 102 in the prestressed composite beam 2: 0 ~ 2350mm (flange + web); The gradient zone of extension section 103: 2350 ~ 3055 mm (the cross-sectional height of extension section 103 is 550 → 469 mm); Central concrete zone: 3055~4945 mm (pure concrete section); Symmetry: The two covered areas are of equal length (3055 mm each) and their midpoints are aligned.

[0040] 6. Implementation Results: (1) The stress concentration factor was reduced from 2.8 in the traditional design to 1.5; (2) Steel usage is reduced by 28% (compared to continuous arrangement); (3) Construction time for key nodes is reduced by 35%; (4) The rotational capacity of the plastic hinge is increased to 0.032 rad (meeting the seismic requirements of high intensity areas).

[0041] In subsequent engineering design, the design scheme of prestressed composite beam 2 can be further optimized based on construction experience and results. For example, the coefficients in the geometric parameter relationships can be adjusted according to different engineering needs and load conditions to achieve better mechanical performance and economic benefits. New materials can also be tried to improve the quality and performance of prestressed composite beam 2.

[0042] In this embodiment, in step A3, a beam end steel plate 107 is installed at the cutoff position where the first flange plate 101 and the first web plate 102 are embedded. Using the beam end steel plate 107 as a reference, the first flange plate 101 and the first web plate 102 are then embedded into place, ensuring better accuracy and stability of the embedding position. The installation of the beam end steel plate 107 must strictly follow the design requirements, and its flatness, verticality, and other deviations must be controlled within a very small range to ensure precise positioning for the embedding of the first flange plate 101 and the first web plate 102. In step A7, the beam end steel plate 107 acts as the end formwork enclosing the concrete pouring cavity 206 of the beam, effectively avoiding the cumbersome procedures of traditional formwork installation and improving construction efficiency. The beam end steel plate 107 is tightly integrated with the concrete 206 of the beam, enhancing the integrity and stability of the prestressed composite beam 2. During subsequent use, the beam end steel plate 107 also provides some protection, preventing damage to the beam ends from external forces.

[0043] In specific implementation, in step A4, a steel pad 106 is welded to each web reinforcement 203 of the prestressed composite beam 2; in step A5, the steel pad 106 with the completed web reinforcement 203 is vertically welded to the first web 102 and / or the beam end steel plate 107 to form a continuous fillet weld. This welding method can significantly enhance the connection strength between the web reinforcement 203 and the first web 102 and the beam end steel plate 107, thereby improving the overall stability of the prestressed composite beam 2. During the welding process, attention should be paid to controlling the welding quality to avoid problems such as incomplete welding or missed welding. The size and shape of the continuous fillet weld must be strictly constructed according to the design requirements to ensure that it meets the relevant standards.

[0044] In practical application, in step A8, the spacing of the stirrups 204 tied in the embedded part of the first steel connector 1 is smaller than the spacing of the stirrups 204 in other parts; a through groove 108 is also reserved on a section of the plate surface at the end of the first web 102 embedded in the prestressed composite beam 2. This through groove 108 is used to arrange tie bars 205 through the web reinforcement 203 of the prestressed composite beam 2. This arrangement of stirrups 204 can effectively enhance the restraint effect of the embedded part of the first steel connector 1, and improve the shear resistance and overall stability of this area. The practice of reserving the through groove 108 and allowing the tie bars 205 to pass through further strengthens the connection and collaborative working ability of the internal reinforcement of the prestressed composite beam 2, so that the prestressed composite beam 2 can better transfer and disperse the force when bearing load, avoiding damage caused by local stress concentration.

[0045] During construction, the dimensional and positional accuracy requirements for the reserved through groove 108 are high, and construction must be carried out strictly in accordance with the design drawings. The dimensions of the through groove 108 should ensure that the tie bar 205 can pass through smoothly, and there should be sufficient clearance between it and the web reinforcement 203 to ensure the convenience of construction operations and the effective anchorage of the tie bar 205. At the same time, the material and specifications of the tie bar 205 must also meet the design requirements, and its tensile strength, elongation and other performance indicators should meet the stress requirements of the prestressed composite beam 2 under different working conditions.

[0046] In actual engineering, strict testing and acceptance of the construction quality of the prestressed composite beam 2 are also required. Besides checking the quality of the reinforcing steel binding and welding, the strength and density of the concrete also need to be tested. Non-destructive testing methods such as ultrasonic testing and rebound testing can be used to test the internal quality of the concrete to ensure that the construction quality of the prestressed composite beam 2 meets the design requirements. The appearance quality of the prestressed composite beam 2 also needs careful inspection to ensure that the surface is smooth, free of cracks, honeycomb, pitting, and other defects. During the acceptance process, evaluation must be strictly carried out in accordance with relevant standards and specifications. Any non-compliant parts must be rectified promptly until they meet the acceptable standards.

[0047] Please refer to Figure 5 In specific application scenarios, the second steel connector 3 and the vertical load-bearing column 4 are constructed according to the following steps: B1: Fabricate the node steel sleeve 401 of the vertical load-bearing column 4 in the prefabrication plant, and determine the position and extension length of the second type steel connector 3 embedded in the column; B2: Weld two transverse stiffening plates 301 at precise positions on the inner wall of the node steel sleeve 401. Grouting holes are reserved on the transverse stiffening plates 301. B3: Ensure that the upper and lower second flange plates 303 of the second steel connector 3 are aligned with the upper and lower two transverse stiffening plates 301 respectively, and then insert the second web plate 302 of the second steel connector 3 between the two transverse stiffening plates 301 through the slot opened on the wall of the node steel sleeve 401. B4: The second web plate 302 is extended to a section of the node steel sleeve 401 and is fully penetrated bevel welded to the inner wall of the node steel sleeve 401 and the two transverse stiffening plates 301; the second flange plate 303 is continuously filled-in welded to the outer wall of the node steel sleeve 401. B5: Weld the node steel sleeve 401 to all the segment steel pipes as one piece to form the column restraint steel pipe of the vertical load-bearing column 4; B6: Hoist and position the column restraint steel pipe, pour column concrete inside the column restraint steel pipe, and ensure that it is filled tightly through the grouting hole of the transverse stiffening plate 301.

[0048] After completing the above construction steps, a rigorous inspection of the connection quality between the second type steel connector 3 and the vertical load-bearing column 4 is required. First, a visual inspection should be conducted on the areas of full penetration bevel welding and continuous fillet welds to check for defects such as incomplete welds, porosity, and slag inclusions. For welds with questionable quality, further testing should be performed using non-destructive testing methods such as ultrasonic testing or radiographic testing to ensure the welding quality meets design requirements. After the column concrete is poured, the concrete strength should be tested. Concrete test blocks can be reserved during the pouring process, cured according to standard curing conditions, and then subjected to compressive strength tests. Simultaneously, non-destructive testing methods such as ultrasonic testing should be used to inspect the internal quality of the column concrete to check for internal defects. For the grouting holes on the transverse stiffening plate 301, it should be checked whether they are completely filled with concrete. A preliminary judgment can be made by tapping; if abnormal sounds are detected, a detailed inspection should be conducted using methods such as core drilling. If incomplete grouting is found, pressure grouting or other measures should be taken promptly.

[0049] like Figures 3 to 5 As shown, specifically, the prestressed composite beam 2 and the vertical load-bearing column 4 are connected on-site according to the following steps: C1: When hoisting the prestressed composite beam 2, the first steel connector 1 extending outward from the end of the prestressed composite beam 2 is roughly aligned with the second steel connector 3 extending outward from the vertical load-bearing column 4. The first web 102 of the first steel connector and the second web 302 of the second steel connector are both reserved with fixing holes in their exposed parts. C2: First, use mounting bolts or some high-strength bolts 6 in conjunction with connecting plate 5 to temporarily fix the first web 102 and the second web 302, and adjust the position and elevation of the prestressed composite beam 2 to the design position; C3: Replace the installation bolts with high-strength bolts 6, and perform initial and final tightening according to design requirements to complete the shear connection between the first web plate 102 and the second web plate 302; C4: The butt joints of the upper and lower first flange plates 101 and the second flange plates 303 are welded on site to complete the bending connection; C5: Perform necessary anti-corrosion and fireproofing treatment on the node area.

[0050] In summary, regarding node connections, the unique design of the first type of steel connector 1 and the second type of steel connector 3, along with a hybrid bolted-welded connection method, ensures a smooth transition in beam end stiffness. This avoids the brittle failure issues common in traditional connection structures under strong earthquakes, improves the ductility and energy dissipation performance of the nodes, and meets the seismic design requirements of "strong nodes and weak components." In terms of construction efficiency, a modular three-dimensional flow operation rule is adopted. After the entire column is constructed, rectangular column grid units are divided. Then, through progressive construction within the same floor and coupling of cross-floor processes, each process is closely connected, reducing waiting time between processes and significantly improving construction progress, breaking through the bottleneck of the traditional "layer-by-layer construction" organizational model. For crack control, the system uses a lightweight composite floor slab 7 with integrated insulation. Compared to ordinary floor slabs, the lightweight composite floor slab 7 does not require excessive increases in thickness to meet the same deformation control requirements, thus avoiding significant increases in structural self-weight and material waste. In terms of thermal performance, the lightweight composite floor slab 7 integrates an insulation layer, avoiding the problem of inconsistent insulation layer integration caused by the need for on-site pouring of the upper concrete layer in conventional composite floor slab construction. This effectively improves the thermal performance of the building envelope. Regarding the selection of connectors, after the first steel connector 1 is embedded to a predetermined depth at the end of the prestressed composite beam 2, its flange stops penetrating further, while the web continues to extend a distance towards the mid-span of the beam. In the extension section 103, its cross-sectional height gradually decreases linearly or non-linearly, ultimately forming a smaller residual cross-sectional height. This design constructs a stiffness buffer / transition zone, the core objective of which is to achieve a continuous and smooth transition of the flexural stiffness of the prestressed composite beam 2's cross-sectional height from the pure concrete region to the region containing the complete steel section, avoiding stress concentration caused by abrupt changes and delaying crack propagation. In this region, cracks in the beam concrete 206 appear later, are more dispersed and finer, which helps maintain the contribution of concrete and makes the overall stiffness degradation more gradual. Simultaneously, this design also improves hysteresis performance. A smoother stiffness change and reduced stress concentration contribute to a fuller hysteresis curve with less pinching effect, meaning the structure has a stronger energy dissipation capacity and less stiffness / strength degradation. In the structural design of the prestressed composite beam 2, the first steel connector 1 adopts a non-continuous design, which not only simplifies the overall structure of the prestressed composite beam 2 but also avoids the complexity of arranging steel sections along the entire length of the beam in traditional designs. This design significantly reduces the amount of steel used, lowers costs, and makes assembly and welding during construction simpler and more efficient. Simultaneously, the simple and clear structure of the first steel connector 1 greatly reduces errors and uncertainties during construction, improving the reliability of the joints and the safety of the overall structure. Furthermore, this invention utilizes the first flange plate 101 to support the longitudinal reinforcement 201 of the prestressed composite beam 2, simplifying the detailed design of the ends of the prestressed composite beam 2 and reducing the cumbersome construction of densely perforated holes or complex bending of the reinforcement in the first flange plate 101.This simple structural design not only reduces construction difficulty and improves construction efficiency, but also reduces potential reliability issues at joints caused by construction quality problems. Furthermore, the through groove 108 pre-reserved on the first web 102 facilitates the through arrangement of the tie bars 205, further enhancing the connection performance of the joint. In addition, this invention further optimizes the bolted-welded connection design to ensure the reliability and efficiency of the connection method. The connection between the first steel connector 1 and the prestressed composite beam 2 and the second steel connector 3 adopts a strategy combining multiple fixing methods. On one hand, the first flange plate 101 of the first steel connector 1 is welded and fixed to the longitudinal reinforcement 201 of the prestressed composite beam 2 using steel pads. This rigid connection method provides a stable force transmission path, ensuring the integrity and synergy of the structure under stress. On the other hand, fixing holes are opened on the exposed parts of the first web 102 and the second web 302 for installing high-strength bolts 6. This bolted connection method not only facilitates rapid on-site installation, positioning, and error adjustment, but also has slip deformation capability, which can dissipate some seismic energy and meet seismic performance requirements. Furthermore, the first flange plate 101 and the second flange plate 303 are aligned and welded after bolt tightening, ensuring a tight connection and final stiffness. Regarding prestressing, this invention utilizes pre-tensioned high-strength prestressed steel reinforcement bundles 202 to apply prestress to the beam concrete 206, effectively enhancing the load-bearing capacity and crack resistance of the entire prestressed composite beam 2. The prestressed steel reinforcement bundles 202 ensure that the concrete beam is uniformly stressed after prestressing, thereby improving the overall stability and durability of the structure. Furthermore, the application of prestressing technology further optimizes the mechanical properties of the prestressed composite beam 2, enabling it to better adapt to various complex working conditions and extreme load conditions. Regarding the vertical load-bearing column 4, a method of extending and welding the transverse stiffening plate 301 to the second web plate 302 is adopted: two transverse stiffening plates 301 with grouting holes are installed inside the node steel sleeve 401, with their height being the same as the upper and lower second flange plates 303. The extension section 103 of the second web plate 302 is welded to the inner wall of the node steel sleeve 401 and to these two transverse stiffening plates 301. This method provides strong bending, shear, and pull-out anchorage for the extended steel section, ensuring that the bending moment and shear force of the prestressed composite beam 2 can be effectively transferred to the column core area. This method significantly enhances the integrity, stiffness, and bearing capacity of the core area of ​​the vertical load-bearing column 4. The transverse stiffening plate 301 acts as a constraint on the core column concrete, improving its strength and deformation capacity. The grouting holes on the transverse stiffening plate 301 ensure the compactness of the concrete pouring in the core area of ​​the joint, preventing voids. Regarding the prefabrication and construction of beams and columns, the construction process of this invention strictly follows scientific and reasonable steps, with clear quality control and technical requirements at each stage to ensure the construction quality and performance of the entire connection joint. In the construction of the prestressed composite beam 2, each step is closely linked.From determining the geometric parameters of the first type of steel connector 1 to welding, embedding, reinforcement arrangement, concrete pouring, and prestressing, all processes underwent practical verification. In particular, when determining the geometric parameters of the first type of steel connector 1, calculations and the application of relevant formulas ensured that it could construct a transition zone with continuously and smoothly changing bending stiffness within the beam, thereby avoiding stress concentration and cracking. Regarding reinforcement arrangement, the spacing of stirrups 204 at different locations was rationally adjusted, and a through groove 108 was reserved on the first web 102 for the passage of tie bars 205, further enhancing the connection performance and overall stability of the joint. In the construction of the vertical load-bearing column 4, from the prefabrication of the joint steel sleeve 401 in the prefabrication plant to determining the position and extension length of the second type of steel connector 3, and then to welding, hoisting, and concrete pouring, the rigor and standardization of the construction were evident. Especially during the installation of the second type of steel connector 3, positioning and welding processes ensure that it provides reliable anchorage for the transfer of bending moment and shear force in the prestressed composite beam 2, while enhancing the integrity, stiffness, and bearing capacity of the core area of ​​the vertical load-bearing column 4. In the on-site connection process between the prestressed composite beam 2 and the vertical load-bearing column 4, temporary fixing is first performed, and the position and elevation are adjusted. Then, high-strength bolts 6 are used to complete the shear connection, and finally welding and anti-corrosion and fireproofing treatment are carried out. This reasonable connection procedure can adapt to complex stress conditions and ensure the stability and durability of the connection parts. Furthermore, effective quality control can be implemented at each stage of the entire construction process, thereby ensuring the reliability of the nodes and the safety of the overall structure.

[0051] The above description discloses only one preferred embodiment of the present invention, and should not be construed as limiting the scope of the present invention. Those skilled in the art will understand that all or part of the processes of the above embodiments can be implemented, and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A prefabricated prestressed steel-concrete composite structure system, comprising n vertical load-bearing columns, characterized in that: n vertical load-bearing columns form m rectangular column grid units on the horizontal building surface. Each rectangular column grid unit is enclosed by 4 vertical load-bearing columns and is distributed at i elevation levels along the building height direction. All column grid units have beam-slab modules of the same height at the same building elevation level. The beam-slab module includes prestressed composite beams arranged along the four sides of the rectangular column grid unit, and a lightweight composite floor slab with an integrated insulation layer laid on the prestressed composite beams at the same level. The prestressed composite beams are connected to the vertical load-bearing columns by bolting and welding through a first type of steel connector and a second type of steel connector. The first type of steel connector creates a transition area with continuously and smoothly changing bending stiffness in the beam body of the prestressed composite beam. Node concrete is also poured between the vertical load-bearing columns, the prestressed composite beams, and the lightweight composite floor slabs. Wherein: n=4m, m>i≥2, and m and i are positive integers.

2. The prefabricated prestressed steel-concrete composite structure system according to claim 1, characterized in that: Perform modular 3D flow operations according to the following rules: S1. Full column construction: On the horizontal building surface, n vertical load-bearing columns are hoisted and positioned according to the construction drawings; S2. Rectangular column grid unit division: The horizontal building plan is divided into m rectangular column grid units by n vertical load-bearing columns; S3. Progressive construction on the same floor: For the j-1 level, execute the following when construction reaches the first matrix column grid unit: Installation of the prestressed composite beam of the first beam-slab module; For the j-1 level, the following should be executed simultaneously during construction of the second matrix column grid unit: Installation of lightweight composite floor slabs for the first beam-slab module; Installation of the prestressed composite beam of the second beam-slab module; For the j-1 level, the following steps are executed simultaneously when construction reaches the a-th matrix column grid unit: Concrete pouring at the nodes of beam-slab module a-2; Installation of lightweight composite floor slab for beam-slab module a-1; Installation of the prestressed composite beam of beam module a; S4. Cross-layer process coupling: Construction at level j will commence when the following conditions are met: Beam installation trigger: After the installation of the prestressed composite beam of the m-th beam-slab module in the j-1 level is completed, if the joint concrete strength of the 1st beam-slab module in the j-1 level reaches the preset threshold, the installation of the prestressed composite beam of the 1st beam-slab module in the j-1 level will be initiated. Pouring Synchronization Trigger: When the m-th unit node at the j-1 level is being poured, the following will be executed synchronously: Installation of the lightweight composite floor slab for the first beam-slab module of the j-th elevation level; Installation of the prestressed composite beam of the second beam-slab module at the j-th elevation level; For the j-th elevation level, the following steps are executed simultaneously when construction reaches the a-th matrix grid unit: Concrete pouring at the nodes of beam-slab module a-2; Installation of lightweight composite floor slab for beam-slab module a-1; Installation of the prestressed composite beam of beam module a; S5: Final finishing touches: Synchronous execution occurs when j=i and a=m: Concrete pouring for the nodes of the (m-1)th beam-slab module; Installation of lightweight composite floor slabs for the m-th beam-slab module; Immediately after the lightweight composite floor slab installation of the m-th beam-slab module is completed, the concrete pouring of the m-th beam-slab module node is carried out. Where: j is the current construction elevation level number: j=2,3...i; 'a' represents the current construction unit number: a = 3, 4, ... m.

3. The prefabricated prestressed steel-concrete composite structure system according to claim 2, characterized in that: The first type of steel connector includes a pair of non-continuous embedded prestressed composite beam ends, first flange plates that support the upper and lower longitudinal reinforcements, and a first web plate located between the two; a section of the first web plate embedded in the prestressed composite beam ends extends toward the mid-span of the beam and forms an extension section with a gradually decreasing cross-sectional height; this extension section is used to construct a transition region in the beam body with a continuous and stable change in bending stiffness.

4. The prefabricated prestressed steel-concrete composite structure system according to claim 3, characterized in that: At least a portion of the cross-sectional height of the extension section varies linearly or nonlinearly.

5. The prefabricated prestressed steel-concrete composite structural system according to claim 4, characterized in that: The overall cross-sectional height of the extension section varies linearly, with its upper and lower edges extending obliquely and converging relatively to form a wedge-shaped structure.

6. The prefabricated prestressed steel-concrete composite structural system according to claim 5, characterized in that: The second type of steel connector includes a pair of transverse stiffening plates with grouting holes disposed in the steel sleeve of the vertical load-bearing column node, and a second web plate disposed between the two; the second web plate extends horizontally out of the node steel sleeve and is aligned and connected with the first web plate; at the upper and lower edges of the section of the second web plate extending out of the node steel sleeve, a second flange plate for receiving the node steel sleeve is also provided respectively; the upper and lower second flange plates are aligned and connected with the upper and lower first flange plates respectively.

7. The prefabricated prestressed steel-concrete composite structural system according to any one of claims 3-5, characterized in that: The first steel connector and the prestressed composite beam are constructed according to the following steps: A1: Determine the embedding depth, flange stopping position, web extension length, and gradient slope of the first type of steel connector according to construction requirements; A2: In the prefabrication plant, the first flange plate and the first web plate are welded according to the construction requirements, and the extension section of the first web plate is cut and processed to form a transition zone with a gradually decreasing cross-sectional height. A3: Insert the first flange plate and the first web plate into place; A4: Weld an upper steel plate to each upper longitudinal reinforcement of the prestressed composite beam, and weld a lower steel plate to each lower longitudinal reinforcement of the prestressed composite beam. A5: The lower steel plate with the lower longitudinal ribs already welded is vertically welded to the first flange plate at the bottom of the first steel connector to form a continuous fillet weld; the upper steel plate with the upper longitudinal ribs already welded is vertically welded to the first flange plate at the top to form a continuous fillet weld. A6: Arrange high-strength prestressed steel wire bundles at the bottom of the prestressed composite beam, and tension and temporarily anchor them according to the pre-tensioning process; A7: Erect end formwork and side formwork to enclose and form the pouring cavity for the prestressed composite beam concrete. A8: Arrange stirrups and other structural reinforcement bars to build the steel reinforcement skeleton of the prestressed composite beam; A9: Pour the concrete for the prestressed composite beam and cure it to the specified strength; A10: After the concrete of the beam reaches the specified strength, the pre-tensioned high-strength prestressed steel bar bundles are released so that the prestress can be transferred to the concrete of the beam through the bond force.

8. The prefabricated prestressed steel-concrete composite structural system according to claim 7, characterized in that: In step A8, the spacing of the stirrups tied in the embedded part of the first steel connector is smaller than the spacing of the stirrups in other parts; a through groove is also reserved on a section of the plate at the end of the first web embedded in the prestressed composite beam, which is used to arrange tie bars through the web reinforcement of the prestressed composite beam.

9. The prefabricated prestressed steel-concrete composite structural system according to claim 7, characterized in that: The second type of steel connector and the vertical load-bearing column are constructed according to the following steps: B1: Fabricate the node steel sleeves of the vertical load-bearing columns in the prefabrication plant, and determine the position and extension length of the second type of steel connectors embedded in the column; B2: Weld two transverse stiffening plates at precise positions on the inner wall of the node steel sleeve. Grouting holes are reserved on the transverse stiffening plates. B3: Ensure that the second flange plates of the upper and lower sections of the second steel connector are aligned with the upper and lower transverse stiffening plates respectively, and then insert the second web plate of the second steel connector between the two transverse stiffening plates through the slot opened on the wall of the node steel sleeve. B4: The section of the second web extending to the node steel sleeve is fully penetrated and bevel-welded to the inner wall of the node steel sleeve and the two transverse stiffening plates; the second flange is continuously filled-in welded to the outer wall of the node steel sleeve. B5: Weld the node steel sleeve to all segment steel pipes as one unit to form the column body restraint steel pipe of the vertical load-bearing column; B6: Hoist and position the column restraint steel pipe, pour column concrete inside the column restraint steel pipe, and ensure that the grouting holes of the transverse stiffening plate are filled tightly.

10. The prefabricated prestressed steel-concrete composite structural system according to claim 6, 8, or 9, characterized in that: The prestressed composite beam is installed according to the following steps: C1: When hoisting the prestressed composite beam, roughly align the first steel connector extending outward from the end of the prestressed composite beam with the second steel connector extending outward from the vertical load-bearing column. The first web of the first steel connector and the second web of the second steel connector are both reserved with fixing holes in their exposed parts. C2: First, use mounting bolts or some high-strength bolts in conjunction with connecting plates to temporarily fix the first and second web plates, and adjust the position and elevation of the prestressed composite beam to the design position; C3: Replace the mounting bolts with high-strength bolts, and perform initial and final tightening according to design requirements to complete the shear connection between the first and second web plates; C4: The butt joints of the upper and lower first flange plates and the second flange plates are welded on site to complete the bending connection; C5: Perform necessary anti-corrosion and fireproofing treatment on the node area.

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