Reinforced concrete column cap joint structure

Abstract

The present application belongs to the field of cast-in-place reinforced concrete frame structure, more particularly to a reinforced concrete column cap joint structure. The present application adds a cylindrical steel sleeve to replace all ring-shaped steel bars and stirrups in the core area of the column cap structure, solving the problem of congestion of steel bars in the column cap structure area. In addition, during the cast-in-place concrete construction process, the steel sleeve in the present application also serves as a component part of the concrete pouring formwork, replacing the traditional irregular and difficult-to-support wooden formwork at the reinforced concrete joint, avoiding material waste caused by cutting of irregular wooden formwork, greatly improving the construction efficiency of formwork erection, and improving the concrete pouring quality. The steel sleeve in the present application is a monolithic steel structure, and after the completion of concrete pouring construction, the steel sleeve can constrain the concrete at the outer edge of the column cap structure, which is stronger than the traditional stirrup constraint, and the overall integrity is better under the combined action of studs and reinforcing ribs.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of cast-in-place reinforced concrete frame structure, more particularly, a reinforced concrete column cap joint structure. BACKGROUND

[0002] In the design of building structure, the core area of beam-column joint is the key part of reinforced concrete frame structure, and is also the key part of design and construction. In practical application, due to the limitation of building conditions, complex joints may occur, in which one column is connected with multiple beams and the beams are not orthogonal to the column. When there are many beams and the beams are not orthogonal to the column, the longitudinal reinforcement of the beams often does not meet the anchorage length requirement. At present, the common method is to set a reinforced concrete column cap at the beam-column joint, and the longitudinal reinforcement of the beams is anchored in the column cap area to solve the problem of insufficient anchorage length of the longitudinal reinforcement of the beams. At the same time, the shear force and bending moment at the end of the beam are transmitted to the column through the column cap to ensure the transmission of the resultant force, avoid local stress concentration, and reduce the risk of local damage of the core area of the joint.

[0003] The current reinforced concrete column cap, whether in terms of force calculation requirement or construction requirement, makes the steel bars in the column cap too dense, resulting in great difficulty in construction of this part, and frequent problems in concrete pouring quality. With the increase of seismic fortification intensity or the increase of complexity of structural system, the steel bars in the column cap will be more dense, the construction difficulty will also increase, and the concrete pouring quality will be more difficult to guarantee. Such problems directly affect the construction quality of the joint, the progress of the main structure, the acceptance rate, and more importantly, the stability and bearing capacity of the whole structure. Therefore, it is necessary to reduce the steel bars in the column cap as much as possible to ensure the construction quality and convenience, while maintaining the necessary strength, stiffness and ductility of the column cap from the design and construction.

[0004] The arrangement mode of the current conventional reinforced concrete column cap joint structure can be referred to Figure 1 and Figure 2 In the same horizontal plane at the top or bottom of the column cap, the horizontal direction (X direction) and vertical direction (Y direction) frame beam single / multi-layer longitudinal reinforcement will pass through the column cap, or all / part of the frame beam longitudinal reinforcement will be anchored in the column cap. In the hoop direction in the column cap area, the column cap single / multi-layer hoop reinforcement will be distributed in the same horizontal plane at the top or bottom of the column cap. In the height range of the column cap area, the column cap stirrup with small layer spacing is densely distributed along the vertical direction (Z direction). The column cap stirrup has large diameter and many stirrup limbs. The column cap stirrup, hoop reinforcement and longitudinal reinforcement of the horizontal direction beam (X direction) and vertical direction beam (Y direction) are arranged in a staggered manner. The main disadvantages of the current conventional column cap structure are as follows:

[0005] 1) The number of steel bars in the current conventional column cap structure is large, and the steel bars in different directions are crossed and stacked, which leads to difficulty in positioning and binding of the steel bars, and position deviation is easy to occur during installation, affecting the bearing capacity of the column cap.

[0006] 2) Due to the dense concentration of rebar in the horizontal (X), vertical (Y), and vertical (Z) directions within the column cap, the theoretical net spacing between rebars is often less than 100mm. In actual construction, this is further impacted by the space occupied by hooks, binding wire joints, and rebar positioning blocks and washers at each layer. Therefore, the net clearance within the column cap, allowing concrete to pass smoothly, is much smaller than 100mm, sometimes even failing to meet the minimum clear spacing requirement of 50mm for concrete pouring. Concrete within the column cap of a concrete frame is difficult to pour and vibrate, potentially causing quality issues such as concrete voids and honeycombs, further weakening the joint strength and impacting construction progress.

[0007] 3) Due to the large number of intersections of concrete components at the column caps, many special-shaped wooden formworks are required, the formwork construction efficiency is low, the cutting of special-shaped formworks is wasteful and cannot be reused, and the large number of special-shaped formwork joints leads to poor appearance of concrete molding.

[0008] 4) Conventional construction joints between upper and lower floors are left in the concrete slab, meaning there will be a construction joint at the base of the column. For high-intensity areas or frame structures with high seismic resistance, additional vertical reinforcement is required at the construction joint to resist horizontal shear forces and improve the seismic resistance of the construction joint. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a reinforced concrete column cap node structure, which can make construction easier and more effectively ensure the bearing capacity of the column cap.

[0010] In order to solve the above technical problems, the present application adopts the following technical scheme: the reinforced concrete column cap joint structure comprises a cast-in-place concrete structure of a reinforced concrete beam and a reinforced concrete column, the reinforced concrete column is arranged vertically, the reinforced concrete beam is arranged horizontally, the radial section of the reinforced concrete beam and the radial section of the reinforced concrete column are both rectangular, the reinforced concrete beam and the reinforced concrete column intersect to form a beam-column joint, the reinforced concrete beam comprises beam longitudinal reinforcement and beam stirrups fixedly connected together, the reinforced concrete column comprises column longitudinal reinforcement and column stirrups fixedly connected together, the beam longitudinal reinforcement and the column longitudinal reinforcement both extend into the core area of the beam-column joint for anchoring, a steel sleeve is further arranged at the beam-column joint, the steel sleeve is a cylindrical sleeve, the steel sleeve is coaxially arranged with the reinforced concrete column, the upper end surface of the steel sleeve is not lower than the upper surface of the reinforced concrete beam, the lower end surface of the steel sleeve is not higher than the lower surface of the reinforced concrete beam, the upper end surface of the steel sleeve is fixedly provided with a steel sleeve top plate arranged horizontally, the lower end surface of the steel sleeve is fixedly provided with a steel sleeve bottom plate arranged horizontally, the outer peripheral edge of the steel sleeve top plate and the inner cavity of the steel sleeve are both in closed connection, the center of the steel sleeve bottom plate is provided with a steel sleeve bottom opening with the same size as the radial section of the reinforced concrete column, when the beam-column joint is located at an intermediate floor, the center of the steel sleeve top plate is provided with a steel sleeve top opening with the same size as the radial section of the reinforced concrete column, the side wall of the steel sleeve is provided with a side reserved opening hole through which the reinforced concrete beam passes, the inner cavity section size of the side reserved opening hole is consistent with the radial section size of the reinforced concrete beam, the inner cavity area of the steel sleeve is not provided with the beam stirrups and the column stirrups, the steel sleeve, the reinforced concrete beam and the reinforced concrete column are fixedly connected into an integral whole through the cast-in-place concrete structure corresponding to the reinforced concrete beam and the reinforced concrete column, and the steel sleeve and the cast-in-place concrete structure filled in the inner cavity form a column cap structure at the beam-column joint.

[0011] Through the above technical scheme, compared with the prior art, the present application adds a cylindrical steel sleeve to replace all the hoop reinforcement and stirrups in the beam-column joint column cap structure range, that is, the problem of the traditional reinforced concrete column cap that “in the column cap area height range, the column cap stirrups are densely distributed along the vertical direction (Z direction) with small layer spacing, the column cap stirrups have large diameter and many limbs; the column cap stirrups, the hoop reinforcement and the longitudinal reinforcement of the horizontal beam (X direction) and the vertical beam (Y direction) are staggered arranged” is avoided; meanwhile, the influence of the space occupation such as hook, binding wire joint, steel reinforcement positioning pad, gasket and the like in actual construction is also avoided, the problem of steel reinforcement congestion in the original column cap area is solved; the on-site operation process of steel reinforcement positioning, binding and bending in the core area of the column cap joint is greatly reduced, the construction difficulty is reduced, and the construction period is saved. The present application is especially suitable for the case that part of the reinforced concrete beams are arranged obliquely relative to the reinforced concrete column.

[0012] In addition, during the concrete casting construction process, the steel sleeve in the present invention also serves as a component of the concrete casting formwork (the bottom opening of the steel sleeve at the center of the steel sleeve bottom plate is directly used for the casting formwork of the reinforced concrete column below the beam-column node, and the outer end surface with the reserved opening on the side is directly used for the casting formwork of the reinforced concrete beam. If it is suitable for the middle floor, the top opening of the steel sleeve at the center of the steel sleeve top plate is directly used for the casting formwork of the reinforced concrete column above the beam-column node), replacing the special-shaped and difficult-to-support wooden formwork at the traditional reinforced concrete column cap node, which not only avoids the material waste caused by the cutting of special-shaped wooden formwork, but also greatly improves the construction efficiency of formwork support. At the same time, the steel sleeve can more effectively prevent bulging and mold expansion during the concrete pouring process than the traditional wooden formwork, and the visual quality of the concrete is better; it solves the problems of the existing beam-column node column cap structure area being difficult to pour and vibrate concrete, and improves the quality of concrete pouring.

[0013] The steel sleeve in the present invention is an integral steel structure. After the concrete pouring construction is completed, the steel sleeve can constrain the concrete at the outer edge of the column cap, which is stronger than the traditional stirrup constraint (in the preferred scheme below, the integrity is better under the combined action of bolts, reinforcing ribs and other components). The seismic bearing capacity of the node is also better than the strength, stiffness and ductility of traditional nodes. It can also enable the node to work as expected in the structural design without premature damage, truly realizing the structural design concept of "strong node and weak component".

[0014] A preferred solution is to pre-install several studs on the lower surface of the steel sleeve top plate and the upper surface of the steel sleeve bottom plate. The studs consist of an integral stud post and a stud cap. The stud cap is located at the end of the stud post, and the end of the stud post without the stud cap is vertically fixed to the corresponding steel sleeve top plate and steel sleeve bottom plate. The studs enhance the bond between the steel sleeve as a whole and the cast-in-place concrete, allowing them to better integrate and work together, ensuring proper load distribution at the beam-column joint.

[0015] A preferred solution is to provide a transverse connection plate between two opposing side walls of the side reserved openings, so that the side reserved openings form multiple small openings spaced vertically apart. The transverse connection plate is integral with the steel sleeve, and a number of studs are pre-fixed to the outer surface of the transverse connection plate. The studs include an integrally fixed stud column and a stud cap. The stud cap is located at the end of the stud column, and the end of the stud column without the stud cap is vertically fixed to the corresponding transverse connection plate. Retaining a transverse connection plate of a certain width at the opening of the side reserved opening can more effectively ensure the structural strength of the steel sleeve after the beam opening (i.e., the above-mentioned side reserved opening) is opened. Similar to the studs installed inside the steel sleeve, the studs installed on the outer surface of the transverse connection plate can also increase the bond between the steel sleeve as a whole and the cast-in-place concrete, allowing them to better integrate and work together, ensuring a reasonable distribution of load at the beam-column joint.

[0016] In order to further effectively ensure the structural strength of the steel sleeve after the beam hole is opened (i.e. the above-mentioned side reserved hole), the preferred solution is that the inner wall of the steel sleeve is fixed with reinforcing ribs arranged in a ring shape along the circumference of the steel sleeve in the area where the transverse reserved connecting plate is located.

[0017] The scheme of the present invention is applicable to the beam-column nodes of the middle floors and the beam-column nodes of the top floors. For the beam-column nodes of the middle floors, that is, a steel sleeve top opening is opened at the center of the steel sleeve top plate. At this time, the preferred scheme is that an upper connecting column is fixedly provided on the upper surface of the steel sleeve top plate in a closed connection. The upper connecting column is coaxially arranged with the reinforced concrete column, and the inner cavity cross-sectional size of the upper connecting column is consistent with the radial cross-sectional size of the reinforced concrete column. The vertical spacing value between the upper end face of the upper connecting column and the upper surface of the steel sleeve top plate in the vertical direction is set to e, e≥the beam width size of the reinforced concrete beam, and at the same time e≥300mm; there is a column construction joint between the concrete of the beam-column node core area corresponding to the inner cavity of the upper connecting column and the reinforced concrete column above the beam-column node, the height position of the column construction joint is not lower than the upper surface of the steel sleeve top plate, and the difference between the elevation value of the column construction joint and the elevation value of the upper surface of the steel sleeve top plate is 0 to 50mm.

[0018] After adopting the above solution, the steel sleeve extends upwards by a certain distance relative to the top surface of the column cap structure, which can effectively solve the problem of insufficient shear resistance of the construction joints caused by the traditional practice of segmented casting of the upper and lower reinforced concrete frame columns at the elevation of the floor beams and slab top surfaces. Compared with the traditional practice of setting a large number of vertical shear steel bars of a certain length at the segmented casting interface of the upper column bottom to resist shear damage of the interface, the columnar steel sleeve of the present invention is higher than the segmented casting surface by a certain distance, which not only reduces the additional vertical shear steel bars at the construction joints, but also serves as a template to ensure the casting quality of the column base. It achieves multiple effects simultaneously, effectively improves the shear resistance of the node construction joints, and further comprehensively improves the seismic performance of the nodes.

[0019] For the top-floor beam-column joints, the steel sleeve top plate is a complete closed structure, so there is no need to set up upper connecting columns.

[0020] In some preferred embodiments, a lower connecting column is fixedly provided on the lower surface of the steel sleeve bottom plate in a closed connection. The lower connecting column is coaxially arranged with the reinforced concrete column, and the inner cavity cross-sectional size of the lower connecting column is consistent with the radial cross-sectional size of the reinforced concrete column. The vertical spacing value between the lower end face of the lower connecting column and the lower surface of the lower connecting column in the vertical direction is set to e, e ≥ the beam width of the reinforced concrete beam, and at the same time e ≥ 300mm. The lower connecting column not only facilitates the pouring formwork of the reinforced concrete column below the beam-column node, but also effectively increases the overall performance between the steel sleeve and the cast-in-place concrete, so that they can better combine and work together to ensure a reasonable distribution of the load on the beam-column node.

[0021] The preferred solution is to align the upper surface of the reinforced concrete beam with the upper end surface of the steel sleeve, and to ensure that the axial length of the steel sleeve is at least 100 mm greater than the beam height of the reinforced concrete beam. This solution ensures that the column cap structure has a reasonable axial length, effectively ensuring the load-bearing capacity of the core area of ​​the column cap node.

[0022] A preferred embodiment of the present invention further includes a reinforced concrete floor slab integrally connected to the reinforced concrete beam and steel sleeve. The top surface of the reinforced concrete floor slab is flush with the top surface of the reinforced concrete beam, while the bottom surface of the reinforced concrete floor slab is higher than the bottom surface of the reinforced concrete beam. The reinforced concrete floor slab includes slab reinforcement, which is fixedly connected to the longitudinal beam reinforcement and beam stirrups. The slab reinforcement at the junction of the reinforced concrete floor slab and the steel sleeve extends to the outer edge of the steel sleeve and is bent. This embodiment effectively ensures the bonding performance of the reinforced concrete floor slab. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0024] Figure 1 It is a top view of a reinforced concrete column cap node structure provided by the prior art;

[0025] Figure 2 It is a side view of a reinforced concrete column cap node structure provided by the prior art;

[0026] Figure 3 This is a top view of a reinforced concrete column cap node structure provided by the present invention;

[0027] Figure 4 This is a side view of a reinforced concrete column cap node structure provided by the present invention;

[0028] Figure 5 This is an axonometric view of a reinforced concrete column cap node structure provided by the present invention;

[0029] Figure 6 yes Figures 3 to 5 An isometric view of a steel sleeve in the illustrated embodiment;

[0030] Figure 7 yes Figure 6 A vertical cross-sectional view of a steel sleeve in the illustrated embodiment;

[0031] Figure 8 yes Figure 6 A top view of a steel sleeve in the illustrated embodiment;

[0032] Figure 9 yes Figure 6 A schematic diagram of the positioning dimensions of a steel sleeve in the embodiment shown;

[0033] Figure 10 It is an axonometric view of another reinforced concrete column cap node structure provided by the present invention;

[0034] Figure 11 yes Figure 10 An isometric view of a steel sleeve in the illustrated embodiment;

[0035] Figure 12 yes Figure 10 A vertical cross-sectional view of a steel sleeve in the illustrated embodiment;

[0036] Figure 13 yes Figure 10A top view of a steel sleeve in the illustrated embodiment.

[0037] The parts in the figure are marked as follows: 1-steel sleeve; 101-steel sleeve side wall plate; 102-stud; 103-side reserved opening; 104-steel sleeve top plate; 105-steel sleeve bottom plate; 106-reinforcement rib; 107-transverse reserved connection plate; 108-upper connecting column; 109-lower connecting column; 2-reinforced concrete beam; 201-beam longitudinal reinforcement; 202-beam stirrups; 3-reinforced concrete column; 301-column longitudinal reinforcement; 302-column stirrups; 4-reinforced concrete floor slab; 5-traditional column cap node; 501-traditional column cap node circumferential reinforcement; 502-traditional column cap node stirrups. DETAILED DESCRIPTION

[0038] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0039] See also Figures 3 to 13The application discloses a reinforced concrete column cap joint structure, which comprises a cast-in-situ concrete structure of a reinforced concrete beam 2 and a reinforced concrete column 3, the reinforced concrete column 3 is arranged in the vertical direction, the reinforced concrete beam 2 is arranged in the horizontal direction, the radial section of the reinforced concrete beam 2 and the radial section of the reinforced concrete column 3 are both rectangular, the reinforced concrete beam 2 and the reinforced concrete column 3 intersect to form a beam-column joint, the reinforced concrete beam 2 comprises beam longitudinal steel bars 201 and beam stirrups 202 which are fixedly connected together, the reinforced concrete column 3 comprises column longitudinal steel bars 301 and column stirrups 302 which are fixedly connected together, the beam longitudinal steel bars 201 and the column longitudinal steel bars 301 both extend into a core area of the beam-column joint for anchoring, a steel sleeve 1 is further arranged at the beam-column joint, the steel sleeve 1 is a cylindrical sleeve, the steel sleeve 1 is coaxially arranged with the reinforced concrete column 3, the upper end surface of the steel sleeve 1 is not lower than the upper surface of the reinforced concrete beam 2, the lower end surface of the steel sleeve 1 is not higher than the lower surface of the reinforced concrete beam 2, a steel sleeve top plate 104 arranged in the horizontal direction is fixedly arranged on the upper end surface of the steel sleeve 1, a steel sleeve bottom plate 105 arranged in the horizontal direction is fixedly arranged on the lower end surface of the steel sleeve 1, the outer peripheral edge of the steel sleeve top plate 104 and the inner cavity of the steel sleeve 1 are in closed connection, the outer peripheral edge of the steel sleeve bottom plate 105 and the inner cavity of the steel sleeve 1 are in closed connection, a steel sleeve bottom opening which is consistent with the radial section size of the reinforced concrete column 3 is arranged at the center of the steel sleeve bottom plate 105, when the beam-column joint is located at a middle floor, a steel sleeve top opening which is consistent with the radial section size of the reinforced concrete column 3 is arranged at the center of the steel sleeve top plate 104, the side wall of the steel sleeve 1 is provided with a side reserved opening hole 103 through which the reinforced concrete beam 2 passes, the inner cavity section size of the side reserved opening hole 103 is consistent with the radial section size of the reinforced concrete beam 2, the inner cavity area of the steel sleeve 1 is not provided with the beam stirrups 202 and the column stirrups 302, the steel sleeve 1, the reinforced concrete beam 2 and the reinforced concrete column 3 are fixedly connected into an integral whole through the cast-in-situ concrete structure corresponding to the reinforced concrete beam 2 and the reinforced concrete column 3, and the steel sleeve 1 and the cast-in-situ concrete structure filled in the inner cavity of the steel sleeve 1 form a column cap structure at the beam-column joint.

[0040] The "reinforced concrete beam 2 and reinforced concrete column 3 intersect to form a beam-column node" described in the present invention can be orthogonal or oblique. "Orthogonal" means that the axial direction of the reinforced concrete beam 2 is perpendicular to one of the side surfaces of the reinforced concrete column 3, and "oblique" means that there is no vertical connection between the axial direction of the reinforced concrete beam 2 and any side surface of the reinforced concrete column 3. The present invention is particularly suitable for situations where some reinforced concrete beams 2 are arranged obliquely relative to the reinforced concrete column 3. The steel sleeve 1 structure can ensure that the longitudinal reinforcement 201 of the beam has sufficient anchorage length in the core area of ​​the beam-column node. In specific implementation, the radius r of the steel sleeve can be reasonably designed according to the anchorage length of the longitudinal reinforcement 201 of the beam. The arrangement of the longitudinal reinforcement 201 of the beam and the longitudinal reinforcement 301 of the column at the column cap structure can refer to the existing technical settings. If the longitudinal reinforcement 201 of the beam is symmetrically arranged on both sides of the column cap structure, the corresponding longitudinal reinforcement 201 of the beam can directly penetrate the column cap structure in the horizontal direction. For the beam-column joints of the middle floors, the reinforced concrete columns 3 of the upper and lower floors are usually arranged coaxially. Accordingly, the column longitudinal reinforcement 301 can directly penetrate the column cap structure vertically.

[0041] When the present invention is implemented, it usually also includes a reinforced concrete floor slab 4 connected to the reinforced concrete beam 2 and the steel sleeve 1. In order to effectively ensure the reliability of the overall structure, the reinforced concrete floor slab 4 is preferably arranged in such a way that the top surface of the reinforced concrete floor slab 4 is flush with the top surface of the reinforced concrete beam 2, and the bottom surface of the reinforced concrete floor slab 4 is higher than the bottom surface of the reinforced concrete beam 2. The reinforced concrete floor slab 4 includes plate steel bars, and the plate steel bars, beam longitudinal steel bars 201 and beam stirrups 202 are fixedly connected into a whole. The plate steel bars at the junction of the reinforced concrete floor slab 4 and the steel sleeve 1 extend to the outer edge of the steel sleeve 1 and are bent.

[0042] The overall construction sequence during the specific implementation of the present invention is as follows:

[0043] Step A, tying and installing the column longitudinal reinforcement 301 and the column stirrups 302 outside the steel sleeve 1; no column stirrups 302 are set within the inner cavity of the steel sleeve 1, nor are traditional column cap node annular reinforcements 501 and traditional column cap node stirrups 502 required, and the steel sleeve 1 is used instead to constrain the concrete at the column cap structure; the wall thickness parameter of the steel sleeve 1 can be equivalently converted according to the structural strength of the traditional column cap node annular reinforcement 501 and traditional column cap node stirrups 502, as long as it is ensured to be not less than the area equivalently converted according to the steel strength of the traditional column cap node annular reinforcement 501 and traditional column cap node stirrups 502, so as to ensure that the steel sleeve 1 has sufficient structural strength, the wall thickness parameter of the steel sleeve 1 can usually be reasonably taken in the range of ≥8mm;

[0044] Step B: installing the column formwork below the node core area;

[0045] Step C: Install the steel sleeve 1 (place it directly on top of the column formwork below the node core area);

[0046] Step D: Install the beam slab bottom formwork and beam side formwork (the template closing surface is the outer surface of the steel sleeve 1, eliminating the need for installing special-shaped wooden formwork in the core area of ​​the traditional column cap node);

[0047] Step E: Tie and install the longitudinal beam reinforcement 201 and the beam stirrups 202; tie and install the slab reinforcement (the slab reinforcement at the junction of the reinforced concrete floor slab 4 and the steel sleeve 1 is extended to the outer edge of the steel sleeve 1 and bent. The bending length must meet the concrete cover thickness requirements);

[0048] Step F, concrete pouring.

[0049] From the above specific embodiments, it can be seen that the present invention installs a steel sleeve 1 at the column cap structure of the beam-column node, and uses the steel sleeve 1 to replace the annular steel bars and stirrups within the original column cap structure ( Figure 1 and Figure 2 The traditional column cap node annular reinforcement 501 and traditional column cap node stirrups 502 shown in the figure solve the problems of a large number of steel bars in the core area of ​​the node, the crossing of steel bars in all directions, and the space occupied by steel bar hooks, positioning pads, steel bar joints, etc., which reduces the construction processes such as stirrup binding and bending, and improves construction efficiency. Since the problem of excessive space occupied by steel bars in the core area of ​​the column cap node is solved, the difficulty of concrete pouring can also be reduced and the quality of concrete pouring can be improved. In addition, during the construction process, the steel sleeve 1 can replace the complex and difficult-to-support special-shaped wooden formwork in the traditional reinforced concrete structure. This replacement not only reduces the material loss caused by cutting the special-shaped wooden formwork, but also significantly improves the work efficiency of the formwork installation. Compared with traditional wooden formwork, the steel sleeve 1 is stronger and can more effectively prevent the problems of mold expansion and deformation during the concrete pouring process, thereby ensuring the quality of concrete pouring. The steel sleeve 1 in the present invention is an integral steel structure. After the concrete pouring construction is completed, the steel sleeve 1 can constrain the concrete at the outer edge of the core area of ​​the column cap node, which is stronger than the traditional stirrup constraint (in the preferred embodiment below, the integrity is better under the combined action of components such as the bolts 102 and the reinforcing ribs 106). The seismic bearing capacity of the node is also better than the strength, stiffness and ductility of the traditional node, and the node can also work as expected in the structural design without premature damage, truly realizing the structural design concept of "strong node and weak component".

[0050] In certain preferred embodiments, a plurality of studs 102 are pre-fixed to the lower surface of the steel sleeve top plate 104 and the upper surface of the steel sleeve bottom plate 105. The studs 102 include a stud column and a stud cap fixed together. The stud cap is located at the end of the stud column. The end of the stud column without the stud cap is vertically fixed to the corresponding steel sleeve top plate 104 and steel sleeve bottom plate 105. More specifically, the studs 102 can generally be fixed by welding and spaced as evenly as possible. The studs 102 are usually made of the same material as the steel sleeve 1. The specific parameters of the studs 102 can be calculated based on actual working conditions. In a specific embodiment of the present invention, the stud column portion of the studs 102 has a diameter of 16 mm and an overall axial length of 80 mm. They are evenly arranged on the inner wall of the steel sleeve 1 at intervals of 200 mm.

[0051] In other preferred embodiments, a transverse connecting plate 107 is provided between two opposing side walls of the reserved side openings 103, forming a plurality of vertically spaced small openings. The transverse connecting plate 107 is integral with the steel sleeve 1. Several studs 102 are pre-fixed to the outer surface of the transverse connecting plate 107. The studs 102 include integrally fixed stud posts and stud caps. The stud caps are located at the ends of the stud posts, and the ends of the stud posts without stud caps are vertically fixed to the corresponding transverse connecting plates 107. It is understood that the arrangement of the transverse connecting plates 107 should meet the structural requirements for the spacing of the beam waist reinforcement. A "transverse connecting plate 107" means that its length is horizontal and its thickness remains consistent with the side wall of the steel sleeve 1 (i.e., the steel sleeve side wall plate 101), forming a component of the steel sleeve side wall plate 101. The width value of the horizontal reserved connecting plate 107 in the vertical direction is set to c, and the specific value of c can be calculated according to the actual working conditions. In the specific embodiment of the present invention, the value of c is 180mm. Generally, one or two horizontal reserved connecting plates 107 are provided (when the beam height ≥800, two horizontal reserved connecting plates 107 are retained; when the beam height is <800, one horizontal reserved connecting plate 107 is retained). The side reserved openings 103 are divided into multiple small openings by the horizontal reserved connecting plate 107. The clearance height dimensions in the vertical direction can be the same or different. When one horizontal reserved connecting plate 107 is retained, the horizontal reserved connecting plate 107 is set in the center, and the clearance height dimension of each small opening in the vertical direction is d=(beam height-c) / 2. When two transverse reserved connecting plates 107 are retained, the clearance height dimension of a small hole in the middle in the vertical direction is set to b, and b can be taken as a fixed value. For example, in a specific embodiment of the present invention, b=210mm, and the clearance height dimensions of the upper and lower small holes in the vertical direction are taken to be the same, both d, d=(beam height-2c-b) / 2.

[0052] In some preferred embodiments, in order to further effectively ensure the structural strength of the steel sleeve 1 after the beam hole is opened (i.e. the side reserved opening hole 103 described above), the inner wall of the steel sleeve 1 is correspondingly fixedly provided with a reinforcing rib 106 arranged in a ring shape along the circumferential direction of the steel sleeve 1 in the region where the transverse reserved connecting plate 107 is located. The plate thickness of the reinforcing rib 106 can be taken as the same as the wall thickness of the steel sleeve side wall plate 101, and the height of the reinforcing rib 106 protruding relative to the inner surface of the steel sleeve side wall plate 101 is generally about 50 mm.

[0053] The scheme of the present application is applicable to the beam-column joints of the intermediate floors and the beam-column joints of the top floor. For the beam-column joints of the intermediate floors, i.e. a steel sleeve top opening is provided at the center of the steel sleeve top plate 104, at this time, the preferred scheme is that the upper surface of the steel sleeve top plate 104 is fixedly provided with an upper connecting column cylinder 108 in a closed connection manner, the upper connecting column cylinder 108 is coaxially arranged with the reinforced concrete column 3, the inner cavity cross-sectional dimension of the upper connecting column cylinder 108 is consistent with the radial cross-sectional dimension of the reinforced concrete column 3, the vertical distance between the upper end surface of the upper connecting column cylinder 108 and the upper surface of the steel sleeve top plate 104 is e, e≥ the beam width dimension of the reinforced concrete beam 2, and at the same time e≥300 mm; there is a column construction joint between the beam-column joint core area concrete corresponding to the inner cavity of the upper connecting column cylinder 108 and the reinforced concrete column 3 at the position above the beam-column joint, the height position of the column construction joint is not lower than the upper surface of the steel sleeve top plate 104, and the difference between the elevation value of the column construction joint and the elevation value of the upper surface of the steel sleeve top plate 104 is 0 to 50 mm. Specifically, the upper end surface of the upper connecting column cylinder 108 is directly used as the pouring formwork of the reinforced concrete column 3 at the position above the beam-column joint, and the upper connecting column cylinder 108 and the steel sleeve top plate 104 can be an integral structure or fixed as a whole by welding. In step F of the above construction process, when the concrete pouring is finally performed, the node core area concrete pouring completion surface elevation is at the top surface elevation of the floor beam and plate, and the allowable deviation is 0 to 50 mm of elevation increase, i.e. it needs to be at least 250 mm lower than the top elevation of the steel sleeve 1, the purpose is to leave the column bottom concrete pouring construction joint within the inner cavity of the steel sleeve 1, so as to improve the shear capacity of the construction joint.

[0054] For the beam-column joints of the top floor, the steel sleeve top plate 104 is a complete closed structure, and the upper connecting column cylinder 108 does not need to be provided.

[0055] In some other preferred embodiments, a lower connecting column 109 is fixedly provided on the lower surface of the steel sleeve bottom plate 105 in a closed connection. The lower connecting column 109 is coaxially arranged with the reinforced concrete column 3, and the inner cavity cross-sectional dimensions of the lower connecting column 109 are consistent with the radial cross-sectional dimensions of the reinforced concrete column 3. The vertical spacing value between the lower end face of the lower connecting column 109 and the lower surface of the lower connecting column 109 in the vertical direction is set to e, e ≥ the beam width of the reinforced concrete beam 2, and at the same time e ≥ 300mm. In specific implementation, the lower end face of the lower connecting column 109 is directly used to connect the casting formwork of the reinforced concrete column 3 at the position below the beam-column node. The lower connecting column 109 and the steel sleeve bottom plate 105 can be an integrated structure or fixed into a whole by welding.

[0056] In some other preferred embodiments, the upper surface of the reinforced concrete beam 2 is flush with the upper end surface of the steel sleeve 1, and the axial length of the steel sleeve 1 is at least 100 mm greater than the beam height of the reinforced concrete beam 2 (the size difference is Figure 9 (a) The beam heights of the reinforced concrete beams 2 can be the same or different. When the beam heights of the reinforced concrete beams 2 are different, the statement "the axial length of the steel sleeve 1 is at least 100 mm greater than the beam height of the reinforced concrete beam 2" should be based on the maximum beam height.

[0057] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0058] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A reinforced concrete column cap node structure, comprising a reinforced concrete beam (2) and a reinforced concrete column (3) of a cast-in-place concrete structure, wherein the reinforced concrete column (3) is arranged in the vertical direction and the reinforced concrete beam (2) is arranged in the horizontal direction, the radial cross-section of the reinforced concrete beam (2) and the radial cross-section of the reinforced concrete column (3) are both rectangular, the reinforced concrete beam (2) and the reinforced concrete column (3) intersect to form a beam-column node, the reinforced concrete beam (2) comprises a beam longitudinal steel bar (201) and a beam stirrup (202) fixedly connected together, the reinforced concrete column (3) comprises a column longitudinal steel bar (301) and a column stirrup (302) fixedly connected together, the beam longitudinal steel bar (201) and the column longitudinal steel bar (301) both extend to the core area of ​​the beam-column node for anchoring, and is characterized in that: The invention comprises a steel sleeve (1) provided at a beam-column node, wherein the steel sleeve (1) is cylindrical and is coaxially arranged with a reinforced concrete column (3), wherein the upper end surface of the steel sleeve (1) is not lower than the upper surface of the reinforced concrete beam (2), and the lower end surface of the steel sleeve (1) is not higher than the lower surface of the reinforced concrete beam (2), wherein the upper end surface of the steel sleeve (1) is fixedly provided with a horizontally arranged steel sleeve top plate (104), and the lower end surface is fixedly provided with a horizontally arranged steel sleeve bottom plate (105), wherein the outer peripheral edge of the steel sleeve top plate (104) and the inner cavity of the steel sleeve (1) are both closedly connected, and the outer peripheral edge of the steel sleeve bottom plate (105) and the inner cavity of the steel sleeve (1) are provided at the center of the steel sleeve bottom plate (105) with a steel sleeve bottom plate having the same radial cross-sectional dimensions as the reinforced concrete column (3). When the beam-column node is located at the middle floor, a steel sleeve top opening that is consistent with the radial cross-sectional size of the reinforced concrete column (3) is opened at the center of the steel sleeve top plate (104); the side wall of the steel sleeve (1) is provided with a side reserved opening (103) for the reinforced concrete beam (2) to pass through, the inner cavity cross-sectional size of the side reserved opening (103) is consistent with the radial cross-sectional size of the reinforced concrete beam (2), the inner cavity area of ​​the steel sleeve (1) is not provided with beam stirrups (202) and column stirrups (302), the steel sleeve (1), the reinforced concrete beam (2) and the reinforced concrete column (3) are fixedly connected to form a whole through the cast-in-situ concrete structures corresponding to the reinforced concrete beam (2) and the reinforced concrete column (3), and the steel sleeve (1) and the cast-in-situ concrete structure filled in its inner cavity form a column cap structure at the beam-column node.

2. The reinforced concrete column cap node structure according to claim 1, characterized in that: A plurality of studs (102) are pre-fixed on the lower surface of the steel sleeve top plate (104) and the upper surface of the steel sleeve bottom plate (105). The studs (102) include stud columns and stud caps fixed into one body. The stud caps are located at the ends of the stud columns. The ends of the stud columns not provided with the stud caps are vertically fixedly connected to the corresponding steel sleeve top plate (104) and the steel sleeve bottom plate (105).

3. The reinforced concrete column cap node structure according to claim 1, characterized in that: A transverse reserved connecting plate (107) is provided between two side walls that are arranged opposite to each other, so that the side reserved openings (103) form a plurality of small holes spaced apart vertically. The transverse reserved connecting plate (107) and the steel sleeve (1) are an integrated structure. A plurality of bolts (102) are pre-fixed on the outer surface of the transverse reserved connecting plate (107). The bolts (102) include bolt columns and bolt caps fixed into one body. The bolt caps are located at the ends of the bolt columns. The end of the bolt column that is not provided with the bolt cap is vertically fixedly connected to the corresponding transverse reserved connecting plate (107).

4. The reinforced concrete column cap node structure according to claim 3, characterized in that: The inner wall of the steel sleeve (1) is fixedly provided with reinforcing ribs (106) arranged in an annular shape along the circumference of the steel sleeve (1) in a region corresponding to the location of the transverse reserved connecting plate (107).

5. The reinforced concrete column cap node structure according to claim 1, characterized in that: When a steel sleeve top opening is opened at the center of the steel sleeve top plate (104), an upper connecting column (108) is fixedly provided on the upper surface of the steel sleeve top plate (104) in a closed connection. The upper connecting column (108) is coaxially arranged with the reinforced concrete column (3), and the inner cavity cross-sectional size of the upper connecting column (108) is consistent with the radial cross-sectional size of the reinforced concrete column (3). The upper end surface of the upper connecting column (108) is vertically aligned with the upper surface of the steel sleeve top plate (104). The vertical spacing value is set to e, e≥the beam width of the reinforced concrete beam (2), and at the same time e≥300mm; a column construction joint exists between the concrete of the core area of ​​the beam-column node corresponding to the inner cavity of the upper connecting column tube (108) and the reinforced concrete column (3) above the beam-column node, the height position of the column construction joint is not lower than the upper surface of the steel sleeve top plate (104), and the difference between the elevation value of the column construction joint and the elevation value of the upper surface of the steel sleeve top plate (104) is 0 to 50mm.

6. The reinforced concrete column cap node structure according to claim 1, characterized in that: A lower connecting column (109) is fixedly provided on the lower surface of the steel sleeve bottom plate (105) in a closed connection. The lower connecting column (109) is coaxially arranged with the reinforced concrete column (3), and the inner cavity cross-sectional size of the lower connecting column (109) is consistent with the radial cross-sectional size of the reinforced concrete column (3). The vertical spacing value between the lower end face of the lower connecting column (109) and the lower surface of the lower connecting column (109) in the vertical direction is set to e, e≥the beam width size of the reinforced concrete beam (2), and at the same time e≥300mm.

7. The reinforced concrete column cap node structure according to claim 1, characterized in that: The upper surface of the reinforced concrete beam (2) is flush with the upper end surface of the steel sleeve (1), and the axial length of the steel sleeve (1) is at least 100 mm greater than the beam height of the reinforced concrete beam (2).

8. The reinforced concrete column cap node structure according to any one of claims 1 to 7, characterized in that: At least part of the reinforced concrete beam (2) is arranged obliquely relative to the reinforced concrete column (3).

9. The reinforced concrete column cap node structure according to any one of claims 1 to 7, characterized in that: The invention also includes a reinforced concrete floor slab (4) connected to the reinforced concrete beam (2) and the steel sleeve (1) as a whole. The top surface of the reinforced concrete floor slab (4) is flush with the top surface of the reinforced concrete beam (2). The bottom surface of the reinforced concrete floor slab (4) is higher than the bottom surface of the reinforced concrete beam (2). The reinforced concrete floor slab (4) includes plate steel bars. The plate steel bars, beam longitudinal steel bars (201) and beam stirrups (202) are fixedly connected to form a whole. The plate steel bars at the junction of the reinforced concrete floor slab (4) and the steel sleeve (1) extend to the outer edge of the steel sleeve (1) and are bent.

Images