Reinforced concrete column cap node structure

Abstract

The invention belongs to the field of cast-in-place reinforced concrete frame structures, and particularly relates to a reinforced concrete column cap joint structure. The cylindrical steel sleeve is additionally arranged to replace all annular steel bars and stirrups within the range of the core area of the column cap structure, and the problem that the steel bars are congested in the area of the column cap structure is solved. Besides, in the concrete cast-in-place construction process, the steel sleeve also serves as a constituent part of a concrete pouring formwork to replace a special-shaped and difficult-to-support wood formwork at a traditional reinforced concrete joint, so that material waste caused by cutting of the special-shaped wood formwork is avoided, the construction efficiency of formwork supporting is greatly improved, and the construction cost is reduced. Meanwhile, the concrete pouring quality is improved. The steel sleeve is of an integral steel structure, after concrete pouring construction is completed, the steel sleeve can restrain concrete on the outer edge of the column cap structure, restraining is higher than that of traditional stirrups, and the integrity is better under the combined action of the studs and the reinforcing ribs.

Description

Technical Field

[0001] The invention belongs to the field of cast-in-place reinforced concrete frame structures, and more specifically to a reinforced concrete column cap node structure. Background Art

[0002] In building structure design, the core area of ​​the beam-column node is a key part of the reinforced concrete frame structure and a key part of the design and construction. In practical applications, due to the limitations of building conditions, complex nodes with "one column and multiple beams" and non-orthogonal connection between beams and columns may appear. When there are many beams and they are not orthogonally connected to the columns, the longitudinal reinforcement of the beams often does not meet the anchorage length requirements. At present, the common practice is to set reinforced concrete column caps at the beam-column nodes, and anchor the longitudinal reinforcement of the beams into 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 beam end are transmitted to the column through the column cap to ensure the transmission of the combined force, avoid local stress concentration, and reduce the risk of local damage in the core area of ​​the node.

[0003] The current reinforced concrete column caps, whether in terms of force calculation requirements or structural requirements, make the steel bars inside the column caps too dense, resulting in great construction difficulty and frequent problems with the quality of concrete pouring. With the increase in earthquake fortification intensity or the increase in the complexity of the structural system, the steel bars inside the column caps will become denser, the construction difficulty will increase accordingly, and the quality of concrete pouring will be even more difficult to guarantee. Such problems directly affect the construction quality of the nodes, the progress and acceptance rate of the main structure, and are more related to the stability and bearing capacity of the entire structure. Therefore, the column caps must maintain the necessary strength, stiffness and ductility in terms of design and construction, so that they can work as expected in the structural design without premature damage, and it is very necessary to reduce the steel bars inside the column caps as much as possible to ensure construction quality and convenience.

[0004] The current conventional reinforced concrete column cap node structure layout can be found in Figure 1 and Figure 2 , in the same horizontal plane at the top or bottom of the column cap, the horizontal (X direction) and vertical (Y direction) frame beam single-layer / multi-layer longitudinal steel bars will pass through the column cap, or all / part of the frame beam longitudinal steel bars will be anchored in the column cap; in the annular direction of the column cap area, the column cap single-layer / multi-layer annular steel bars will be distributed in the same horizontal plane at the top or bottom of the column cap; within the height range of the column cap area, the column cap stirrups with small interlayer spacing are densely distributed along the vertical direction (Z direction), the column cap stirrups have large diameters and many stirrup legs; the column cap stirrups, annular steel bars and the longitudinal bars of the horizontal beam (X direction) and vertical beam (Y direction) are staggered. Its main disadvantages are as follows:

[0005] 1) There are many steel bars in the existing conventional column cap structure, and the steel bars in all directions are crossed and stacked, which makes it difficult to position and tie the steel bars. Position deviation is easy to occur during installation, affecting the bearing capacity of the column cap.

[0006] 2) Due to the dense reinforcement in the horizontal (X), vertical (Y) and vertical (Z) directions of the column cap, the theoretical net spacing of the reinforcement is often less than 100mm. In actual construction, it is also affected by the space occupied by hooks, binding wire joints, and positioning pads and gaskets of each layer of reinforcement. Therefore, the net size of the gap in the column cap that allows concrete to pass smoothly is much smaller than 100mm, and sometimes even cannot meet the minimum net spacing requirement of 50mm for concrete pouring. Concrete is difficult to pour and vibrate in the range of the concrete frame column cap, which may cause quality problems such as concrete voids and honeycombs, further weakening the strength of the node and affecting the construction progress.

[0007] 3) Due to the large number of cross-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 there are many joints of special-shaped formworks, resulting in poor appearance of concrete molding.

[0008] 4) The construction joints of the conventional upper and lower floors are left on the concrete slab surface, that is, there will be construction joints at the base of the columns. For high-intensity areas or high-seismic grade frame structures, additional vertical reinforcement is required at the construction joints to resist horizontal shear forces and improve the seismic resistance of the construction joints. 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 the construction easier and at the same time can more effectively ensure the bearing capacity of the column cap.

[0010] In order to solve the above technical problems, the present invention adopts the following technical solutions: a reinforced concrete column cap node structure, including a reinforced concrete beam and a reinforced concrete column of a cast-in-place concrete structure, the reinforced concrete column is arranged vertically, and the reinforced concrete beam is arranged horizontally. The radial cross-section of the reinforced concrete beam and the radial cross-section of the reinforced concrete column are both rectangular. The reinforced concrete beam and the reinforced concrete column intersect to form a beam-column node. The reinforced concrete beam includes a beam longitudinal steel bar and a beam stirrup fixedly connected together, and the reinforced concrete column includes a column longitudinal steel bar and a column stirrup fixedly connected together. The beam longitudinal steel bar and the column longitudinal steel bar are both extended to the core area of ​​the beam-column node for anchoring. A steel sleeve is also provided at the beam-column node. The steel sleeve is cylindrical, and 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, and 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 horizontally arranged The steel sleeve top plate and the lower end surface are fixedly provided with a horizontally arranged steel sleeve bottom plate, and the outer peripheral edge of the steel sleeve top plate and the inner cavity of the steel sleeve, as well as the outer peripheral edge of the steel sleeve bottom plate and the inner cavity of the steel sleeve are all closed connections; a steel sleeve bottom opening consistent with the radial cross-sectional size of the reinforced concrete column is opened at the center of the steel sleeve bottom plate; when the beam-column node is located at the middle floor, a steel sleeve top opening consistent with the radial cross-sectional size of the reinforced concrete column is opened at the center of the steel sleeve top plate; the side wall of the steel sleeve is provided with a side reserved opening for the reinforced concrete beam to pass through, and the inner cavity cross-sectional size of the side reserved opening is consistent with the radial cross-sectional size of the reinforced concrete beam, and beam stirrups and column stirrups are not provided in the inner cavity area of ​​the steel sleeve, and the steel sleeve, reinforced concrete beam and reinforced concrete column are fixedly connected into a whole through the cast-in-place concrete structures corresponding to the reinforced concrete beam and the reinforced concrete column, and the steel sleeve and the cast-in-place concrete structure filled with its inner cavity form a column cap structure at the beam-column node.

[0011] It can be known from the above technical scheme that compared with the prior art, the present invention adds a cylindrical steel sleeve to replace all the annular steel bars and stirrups within the column cap structure of the beam-column node, which eliminates the problem described in the traditional reinforced concrete column cap that "within the height range of the column cap area, column cap stirrups with small interlayer spacing are densely distributed along the vertical direction (Z direction), the column cap stirrups have a large diameter, and the number of stirrup limbs is large; the column cap stirrups, annular steel bars and the longitudinal bars of the horizontal beam (X direction) and the vertical beam (Y direction) are staggered"; at the same time, it also avoids the influence of the space occupation of the hooks, binding wire joints, and each layer of steel bar positioning pads, gaskets, etc. generated in the actual construction, solves the problem of steel bar congestion in the original column cap area; greatly reduces the on-site in-situ operation procedures such as steel bar positioning, binding, and bending in the core area of ​​the column cap node, reduces the construction difficulty, and saves the construction period. The present invention is particularly suitable for the situation where some reinforced concrete beams are arranged obliquely relative to the reinforced concrete columns.

[0012] In addition, during the concrete cast-in-place 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 waste of materials 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 the bulging and expansion of the formwork during the concrete pouring process than the traditional wooden formwork, and the concrete has better sensory quality; it solves the problems of the difficulty of pouring and vibrating the concrete in the column cap structure area of ​​the existing beam-column node, 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 traditional node strength, stiffness and ductility. It can also make the node work as expected in the structural design without premature damage, truly realizing the structural design concept of "strong node and weak component".

[0014] The preferred solution is that a plurality of studs are pre-fixed on the lower surface of the steel sleeve top plate and the upper surface of the steel sleeve bottom plate, and the studs include stud columns and stud caps fixed as one, the stud caps are located at the ends of the stud columns, and the ends of the stud columns not provided with stud caps are vertically fixedly connected to the corresponding steel sleeve top plate and steel sleeve bottom plate. The studs can increase the bonding force between the steel sleeve as a whole and the cast-in-place concrete, so that they can be better combined and work together, ensuring that the load on the beam-column node is reasonably distributed.

[0015] The preferred solution is that there is a transverse reserved connection plate between two side walls that are arranged opposite to each other, so that the side reserved opening forms a plurality of small openings spaced apart vertically, the transverse reserved connection plate and the steel sleeve are an integral structure, and a plurality of bolts are pre-fixed on the outer surface of the transverse reserved connection plate, the bolts include a bolt column and a bolt cap that are fixed into one, the bolt cap is located at the end of the bolt column, and the end of the bolt column that is not provided with the bolt cap is vertically fixedly connected to the corresponding transverse reserved connection plate. A transverse reserved connection plate of a certain width is reserved at the opening of the reserved opening, which can more effectively ensure the structural strength of the steel sleeve after the beam hole (i.e., the above-mentioned side reserved opening) is opened. Similar to the bolts arranged inside the above-mentioned steel sleeve, the bolts arranged on the outer surface of the transverse reserved connection plate can also increase the bonding force between the steel sleeve as a whole and the cast-in-place concrete, so that they can be better combined and work together to ensure a reasonable distribution of the load on the beam-column node.

[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 both 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, and 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 of the reinforced concrete beam, and at the same time e≥300mm; there is a column construction joint between the concrete of the core area of ​​the beam-column node 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 scheme, the steel sleeve extends upwards 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 segmented casting construction of the upper and lower reinforced concrete frame columns at the elevation of the floor beams and slab top surfaces in the traditional practice. Compared with the traditional practice of setting a certain length of vertical shear steel bars at the segmented casting interface of the upper column bottom to resist shear damage at 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 has multiple effects, 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 schemes, the lower surface of the steel sleeve bottom plate is fixedly provided with a lower connecting column 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, and 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 can not only facilitate the pouring formwork of the reinforced concrete column below the beam-column node, but also effectively increase the overall performance between the steel sleeve and the cast-in-place concrete, so that they can be better combined and work together to ensure the reasonable distribution of the load on the beam-column node.

[0021] The preferred solution is that the upper surface of the reinforced concrete beam is flush with the upper end surface of the steel sleeve, and the axial length of the steel sleeve is at least 100 mm greater than the beam height of the reinforced concrete beam. After adopting the above solution, the column cap structure has a reasonable axial length, which can more effectively ensure the bearing capacity of the core area of ​​the column cap structure node.

[0022] The preferred solution is that the present invention also includes a reinforced concrete floor slab connected to the reinforced concrete beam and the steel sleeve as a whole, the top surface of the reinforced concrete floor slab is flush with the top surface of the reinforced concrete beam, 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 plate steel bars, the plate steel bars, the beam longitudinal steel bars and the beam stirrups are fixedly connected as a whole, and the plate steel bars at the junction of the reinforced concrete floor slab and the steel sleeve extend to the outer edge of the steel sleeve and are bent. After adopting the above solution, the bonding performance of the reinforced concrete floor slab can be effectively guaranteed. 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 drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying 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 It is a top view of a reinforced concrete column cap node structure provided by the present invention;

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

[0028] Figure 5 It is an isometric 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] Fig. 9 yes Figure 6 A schematic diagram of the positioning dimensions of a steel sleeve in the illustrated embodiment during implementation;

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

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

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

[0036] Fig.13 yes Fig.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-bolt; 103-side reserved opening; 104-steel sleeve top plate; 105-steel sleeve bottom plate; 106-reinforcement ribs; 107-transverse reserved connecting 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 technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] See also Figures 3 to 13The present invention discloses 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 vertically, and the reinforced concrete beam 2 is arranged horizontally, wherein the radial cross-section of the reinforced concrete beam 2 and the radial cross-section of the reinforced concrete column 3 are both rectangular, and the reinforced concrete beam 2 and the reinforced concrete column 3 intersect to form a beam-column node, wherein the reinforced concrete beam 2 comprises a beam longitudinal steel bar 201 and a beam stirrup 202 fixedly connected together, and the reinforced concrete column 3 comprises a The column longitudinal steel bars 301 and column stirrups 302, the beam longitudinal steel bars 201 and the column longitudinal steel bars 301 are all extended to the core area of ​​the beam-column node for anchoring. A steel sleeve 1 is also provided at the beam-column node. The steel sleeve 1 is cylindrical and 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, and the lower end surface of the steel sleeve 1 is not higher than the lower surface of the reinforced concrete beam 2. The upper end surface of the steel sleeve 1 is fixedly provided with a horizontally arranged steel sleeve top plate 104, A horizontally arranged steel sleeve bottom plate 105 is fixedly provided on the lower end surface, and the outer peripheral edge of the steel sleeve top plate 104 and the inner cavity of the steel sleeve 1, as well as the outer peripheral edge of the steel sleeve bottom plate 105 and the inner cavity of the steel sleeve 1 are all closed connections; a steel sleeve bottom opening consistent with the radial cross-sectional dimensions of the reinforced concrete column 3 is opened at the center of the steel sleeve bottom plate 105; when the beam-column node is located at the middle floor, a steel sleeve top opening consistent with the radial cross-sectional dimensions of the reinforced concrete column 3 is opened at the center of the steel sleeve top plate 104; the steel sleeve The side wall of 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, and the inner cavity area of ​​the steel sleeve 1 is not provided with beam stirrups 202 and column stirrups 302. The steel sleeve 1, reinforced concrete beam 2 and reinforced concrete column 3 are fixedly connected into a whole through the cast-in-place concrete structure corresponding to the reinforced concrete beam 2 and the reinforced concrete column 3. The steel sleeve 1 and the cast-in-place concrete structure filled in its inner cavity form a column cap structure at the beam-column node. "Column cap structure" means that the radial cross-sectional size of this part is larger than the radial cross-sectional size of the reinforced concrete column 3. The "radial cross-section" described in the present invention refers to the cross-section perpendicular to the axial direction.

[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 the situation where some reinforced concrete beams 2 are arranged obliquely relative to the reinforced concrete column 3. The steel sleeve 1 structure can make the longitudinal reinforcement 201 of the beam have 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 prior art. 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, and accordingly, the column longitudinal reinforcement 301 directly passes through 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 as a whole. 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 as 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, the column longitudinal reinforcement 301 is tied and installed, and the column stirrups 302 outside the steel sleeve 1 are tied and installed; no column stirrups 302 are set in the inner cavity of the steel sleeve 1, and the traditional column cap node annular reinforcement 501 and the traditional column cap node stirrups 502 are not set, and the steel sleeve 1 is used to play the role of restraining 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 the 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 the traditional column cap node stirrups 502, so as to ensure that the steel sleeve 1 has sufficient structural strength, and the wall thickness parameter of the steel sleeve 1 can usually be reasonably taken in the range of ≥8mm;

[0044] Step B, installation of column formwork below the node core area;

[0045] Step C, installation of the steel sleeve 1 (directly placed on the top of the column formwork below the node core area);

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

[0047] Step E, tying and installing the longitudinal beam reinforcement 201 and the beam stirrups 202; tying the plate reinforcement (the plate 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, and the bending length must meet the requirements of the concrete cover thickness);

[0048] Step F, concrete pouring.

[0049] It can be seen from the above specific implementation 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., reduce the construction processes such as stirrup binding and bending, and improve the 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 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 formworks in traditional reinforced concrete structures. This replacement not only reduces the material loss caused by cutting special-shaped wooden formworks, but also significantly improves the work efficiency of formwork installation. Compared with traditional wooden formworks, 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 studs 102 and the reinforcing ribs 106). The seismic bearing capacity of the node is also better than the traditional node strength, stiffness and ductility. It can also make the node 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 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 a stud column and a stud cap fixed into one body. The stud cap is located at the end of the stud column. The end of the stud column without the stud cap is vertically fixedly connected to the corresponding steel sleeve top plate 104 and the steel sleeve bottom plate 105. More specifically, the studs 102 can generally be fixed by welding and distributed 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 according to the actual working conditions. In a specific embodiment of the present invention, the diameter of the stud column part of the studs 102 is 16 mm, the overall axial length is 80 mm, and they are evenly arranged on the inner wall of the steel sleeve 1 at a spacing of 200 mm.

[0051] In some other preferred embodiments, a transverse reserved connecting plate 107 is provided between two side walls of the side reserved opening 103 arranged opposite to each other, so that the side reserved opening 103 forms a plurality of small openings spaced apart vertically, the transverse reserved connecting plate 107 is an integral structure with the steel sleeve 1, and a plurality of studs 102 are pre-fixed on the outer surface of the transverse reserved connecting plate 107, the studs 102 include a stud column and a stud cap fixed into one, 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 fixedly connected to the corresponding transverse reserved connecting plate 107. It can be understood that the arrangement of the transverse reserved connecting plate 107 should meet the structural requirements of the spacing of the beam waist reinforcement. The "transverse reserved connecting plate 107" means that its length direction is horizontal, and its plate thickness is still consistent with the side wall plate of the steel sleeve 1 (i.e., the steel sleeve side wall plate 101), and is a component of the steel sleeve side wall plate 101. The width value of the horizontal reserved connection 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 connection plates 108 are provided (when the beam height ≥ 800, two horizontal reserved connection plates 108 are reserved; when the beam height is < 800, one horizontal reserved connection plate 108 is reserved). The clearance height dimensions of the multiple small openings into which the reserved opening 103 is divided by the horizontal reserved connection plate 108 in the vertical direction can be the same or different. When one horizontal reserved connection plate 108 is reserved, the horizontal reserved connection plate 108 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 horizontal reserved connecting plates 108 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 (i.e., the above-mentioned side reserved hole 103) is opened, 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 the area where the transverse reserved connecting plate 107 is located. The plate thickness of the reinforcing ribs 106 can be taken to be the same as the wall thickness of the steel sleeve side wall plate 101, and the height of the reinforcing ribs 106 protruding relative to the inner surface of the steel sleeve side wall plate 101 can generally be taken to be about 50 mm.

[0053] The scheme of the present invention is applicable to both 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, the center of the steel sleeve top plate 104 is provided with a steel sleeve top opening. 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 108 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 vertical spacing value between the end face and the upper surface of the steel sleeve top plate 104 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; there is a column construction joint between the concrete of the core area of ​​the beam-column node corresponding to the inner cavity of the upper connecting column 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. In specific implementation, the upper end face of the upper connecting column 108 is directly used to connect the casting template of the reinforced concrete column 3 above the beam-column node, and the upper connecting column 108 and the steel sleeve top plate 104 can be an integrated structure, or fixed into a whole by welding. In step F of the above construction process, when the concrete is poured at the end, the elevation of the finished surface of the concrete pouring in the node core area is at the elevation of the top surface of the floor beams and slabs, and the allowable deviation is an increase of 0 to 50 mm in elevation, that is, it must be at least 250 mm lower than the top elevation of the steel sleeve 1. The purpose is to keep the construction joint of the column bottom concrete pouring within the inner cavity of the steel sleeve 1 to improve the shear resistance of the construction joint.

[0054] For the beam-column joints at the top floor, the steel sleeve top plate 104 is a complete closed structure, and there is no need to set up the upper connecting column 108.

[0055] In some other preferred embodiments, the lower surface of the steel sleeve bottom plate 105 is fixedly provided with a lower connecting column 109 in a closed connection, the lower connecting column 109 is coaxially arranged with the reinforced concrete column 3, and the inner cavity cross-sectional dimension of the lower connecting column 109 is consistent with the radial cross-sectional dimension of the reinforced concrete column 3, and the vertical spacing value between the lower end surface 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 dimension of the reinforced concrete beam 2, and at the same time e ≥ 300mm. In specific implementation, the lower end surface of the lower connecting column 109 is directly used to connect the casting template of the reinforced concrete column 3 at the position below the beam-column node, and 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 Fig. 9 a). The beam heights of the reinforced concrete beams 2 may be the same or different. When the beam heights of the reinforced concrete beams 2 are different, 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 enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be 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 will not be limited to the embodiments shown herein, but rather 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, and the radial cross-section of the reinforced concrete beam (2) and the radial cross-section of the reinforced concrete column (3) are both rectangular, and 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, and the reinforced concrete column (3) comprises a column longitudinal steel bar (301) and a column stirrup (302) fixedly connected together, and the beam longitudinal steel bar (201) and the column longitudinal steel bar (301) are both extended to the core area of ​​the beam-column node for anchoring, characterized in that: The invention comprises a steel sleeve (1) arranged at a beam-column node, the steel sleeve (1) being cylindrical, and being coaxially arranged with a reinforced concrete column (3), the upper end surface of the steel sleeve (1) being not lower than the upper surface of the reinforced concrete beam (2), and the lower end surface of the steel sleeve (1) being not higher than the lower surface of the reinforced concrete beam (2), the upper end surface of the steel sleeve (1) being fixedly provided with a horizontally arranged steel sleeve top plate (104), and the lower end surface being fixedly provided with a horizontally arranged steel sleeve bottom plate (105), the outer peripheral edge of the steel sleeve top plate (104) and the inner cavity of the steel sleeve (1), and the outer peripheral edge of the steel sleeve bottom plate (105) and the inner cavity of the steel sleeve (1) being both closedly connected; a steel sleeve bottom plate (105) having a radial cross-sectional size consistent with that of the reinforced concrete column (3) is provided at the center of the steel sleeve bottom plate (105). When the beam-column node is located at the middle floor, a steel sleeve top opening that is consistent with the radial cross-sectional dimensions of the reinforced concrete column (3) is opened at the center of the steel sleeve top plate (104); a side reserved opening (103) is provided on the side wall of the steel sleeve (1) for the reinforced concrete beam (2) to pass through, the inner cavity cross-sectional dimensions of the side reserved opening (103) are consistent with the radial cross-sectional dimensions 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-place concrete structures corresponding to the reinforced concrete beam (2) and the reinforced concrete column (3), and the steel sleeve (1) and the cast-in-place 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 bolts (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 bolts (102) include bolt columns and bolt caps fixed together. The bolt caps are located at the ends of the bolt columns. The ends of the bolt columns not provided with the bolt 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 openings that are spaced apart vertically. The transverse reserved connecting plate (107) and the steel sleeve (1) are an integral 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 that are fixed together. The bolt caps are located at the ends of the bolt columns. The end of the bolt columns that is not provided with the bolt caps 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 provided 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 dimensions of the upper connecting column (108) are consistent with the radial cross-sectional dimensions of the reinforced concrete column (3), and the upper end surface of the upper connecting column (108) is vertically aligned with the upper surface of the steel sleeve top plate (104) in the vertical direction. 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 in 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 upper surface elevation value 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 and sealedly provided on the lower surface of the steel sleeve bottom plate (105); the lower connecting column (109) is coaxially arranged with the reinforced concrete column (3); and the inner cavity cross-sectional dimension of the lower connecting column (109) is consistent with the radial cross-sectional dimension 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 dimension 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: It 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, the beam longitudinal steel bars (201) and the beam stirrups (202) are fixedly connected to form a whole, and 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.

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