A node connection device for adding a new beam to an existing reinforced concrete column beam

Abstract

The present invention discloses a node connection device for adding a beam to an existing reinforced concrete column and beam, and belongs to the technical field of building reinforcement. The device comprises a hoop enclosed on the outer periphery of the existing reinforced concrete column or concrete beam, a horizontal connection device and a vertical connection device fixedly connected to the hoop, anchoring bars, and a newly added beam support structure fixedly connected to the horizontal connection device and the vertical connection device. The hoop is provided with a plurality of through holes, and the anchoring bars pass through the through holes and are fixed to the existing reinforced concrete column or concrete beam. The outer surface of the hoop is not higher than the outer surface of the existing reinforced concrete column or concrete beam, and the hoop is fixed along the outer peripheral surface of the existing reinforced concrete column or concrete beam to form a whole. The device reduces the difficulty of node connection construction between the newly added reinforced concrete beam and the existing frame column by adopting a simple steel corbel connection structure, reduces the weakening of the cross section of the existing frame column, improves the bending and shear bearing capacity of the node area, and ensures that the newly added reinforced concrete beam and the existing frame column can work well together.

Description

Technical Field

[0001] The invention relates to a node connection device for adding a new beam to an existing reinforced concrete column beam, belonging to the technical field of building reinforcement. Background Art

[0002] As the building is used for a longer time, it will be damaged by human or natural factors, which will weaken the strength of the building's own structure and even cause the building to collapse in severe cases. In addition, when the function of the building changes in whole or in part, it is likely that some new load-bearing structures will need to be added. For example, in order to increase the business or use area, the original atrium structure that runs through multiple floors is cancelled and multiple closed floors are formed. Therefore, during the use of the building, not only does it need to strengthen the structure of the building itself, but it is often necessary to add new supporting load-bearing structures between the existing reinforced concrete columns or reinforced concrete beams.

[0003] At present, in the reconstruction of existing building structures, the conventional method of reinforcing the existing reinforced concrete frame columns by adding frame beams (or cantilever beams) is to directly implant the longitudinal force-bearing steel bars of the newly added frame beams (or cantilever beams) into the columns at the corresponding positions on the existing frame columns by chemical implantation. When using the traditional method to root the newly added beams, three problems are often encountered during the construction process: First, when the newly added beams are equipped with a large number of longitudinal steel bars, the minimum spacing of the implanted steel bars (S min ≥5d) cannot be met, affecting the anchoring effect of rebar planting; secondly, when the newly added longitudinal reinforcement of the beam is configured with more, the drilling holes are too concentrated within the rebar planting range, which greatly weakens the cross-section of the original frame column and affects the structural safety of the original frame column; thirdly, when the diameter of the newly added longitudinal reinforcement of the beam is large, the cross-sectional size of the original frame column cannot meet the minimum rebar planting anchoring depth required by theoretical calculation. In addition, the excessive rebar planting depth also causes great difficulties for the rebar planting construction. Summary of the invention

[0004] In order to solve the technical problems in the prior art that the spacing of the embedded steel bars cannot meet the requirements of the technical specifications, the embedded steel bar drilling holes are concentrated, the cross-section of the existing concrete column or concrete beam is too weakened, the safety of the existing structure is reduced, and the depth of the longitudinal steel bars of the newly added beam cannot meet the requirements, the present invention provides a node connection device for adding a beam to an existing reinforced concrete column or beam, and the technical solution adopted is as follows:

[0005] A node connection device for adding a beam to an existing reinforced concrete column or beam, the device comprises a hoop 1 nested and enclosed in the outer periphery of the connection of the existing reinforced concrete column or concrete beam, a horizontal connection device 2 and a vertical connection device 3 fixedly connected to the hoop 1, anchoring bars 5, and a newly added beam support structure fixedly connected to the horizontal connection device 2 and the vertical connection device 3; the hoop 1 is provided with a plurality of through holes, the anchoring bars 5 pass through the through holes and are fixed to the existing reinforced concrete column or concrete beam; the hoop 1 is fixed along the outer periphery of the existing reinforced concrete column or concrete beam to form a whole.

[0006] Preferably, the horizontal connection device 2 comprises a plurality of horizontally arranged top plates 21 and bottom plates 22; the plurality of top plates 21 are in the same horizontal plane and their edges are welded and fixed to form an annular structure.

[0007] More preferably, the vertical connecting device 3 is located between the top plate 21 and the bottom plate 22, and the vertical connecting device 3 includes a main vertical plate 31 welded and fixed to the lower surface of the top plate 21 and the upper surface of the bottom plate 22, and side vertical plates 32 located on both sides of the main vertical plate 31 and fixedly connected to at least the lower surface of the top plate 21.

[0008] More preferably, the newly added beam support structure is a longitudinal reinforcement device 4 fixedly connected to the upper surface of the top plate 21 , the lower surface of the bottom plate 22 , and the sides of the main vertical plate 31 and the side vertical plate 32 .

[0009] Preferably, the vertical connecting device 3 includes a cantilever beam 6 located between the top plate 21 and the bottom plate 22; the cantilever beam 61 includes an I-shaped steel beam and a main vertical plate 31; the main vertical plate 31 is welded and fixed to the outer side surface of the hoop 1; the upper surface of the I-shaped steel beam is welded and fixed to the lower surface of the top plate 21, and the lower surface is welded and fixed to the upper surface of the bottom plate 22.

[0010] More preferably, a plurality of through holes are correspondingly provided on the vertical surface of the I-shaped steel beam and the main vertical plate 31, and the I-shaped steel beam and the main vertical plate 31 are connected and fixed by means of a fixing device 61 penetrating the through holes.

[0011] More preferably, the anchor bar 5 is implanted and anchored on the existing reinforced concrete column or concrete beam through the through holes evenly arranged on the hoop 1; or is welded and fixed to the steel bars in the existing reinforced concrete column or concrete beam through the through holes arranged on the hoop 1.

[0012] Preferably, the outer surface of the hoop 1 is not higher than the outer surface of the existing reinforced concrete column.

[0013] Preferably, a high-strength non-shrinkage concrete grouting material layer for bonding is provided between the hoop 1 and the existing reinforced concrete column or concrete beam.

[0014] More preferably, the ferrule 1 is a metal ferrule; further, the ferrule 1 is a steel ferrule with a thickness of not less than 10 mm.

[0015] Another object of the present invention is to provide a method for constructing a newly added reinforced concrete beam using any of the above-mentioned node connection devices, the steps of the method are as follows:

[0016] 1) Remove the concrete protective layer on all four sides of the existing reinforced concrete column where the reinforced concrete beam or cantilever beam needs to be newly added to expose the existing column longitudinal reinforcement and stirrups;

[0017] 2) Calculate the number and diameter of anchor bars to be implanted in the newly added reinforced concrete beams, and implant the anchor bars using the chemical implantation method based on the calculation results;

[0018] 3) installing a steel hoop sleeve with through holes corresponding to the positions of the anchor bars in step (2) on the newly added reinforced concrete beam, welding the adjacent hoop sleeve plates together, and then welding each anchor bar to the steel hoop sleeve;

[0019] 4) Weld the horizontal connection device and the vertical connection device on the outside of the steel hoop;

[0020] 5) welding the longitudinal reinforcement of the newly added reinforced concrete column to the horizontal connection device and the vertical connection device described in step (4), and fixing the longitudinal reinforcement with stirrups;

[0021] 6) Use high-strength non-shrinkage concrete grouting material to fill and compact the gap between the steel sleeve and the existing column;

[0022] 7) Pour concrete for the newly added beams.

[0023] Preferably, the thickness of the steel hoop sleeve is not less than 10 mm.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The node connection device provided by the present invention reduces the difficulty of node connection construction between the newly added reinforced concrete beam and the existing frame column by adopting a simple steel bracket connection structure, reduces the cross-sectional weakening of the existing frame column, improves the bending and shear bearing capacity of the node area, and ensures that the newly added reinforced concrete beam and the existing frame column can work well together.

[0026] The node connection device provided by the present invention creatively fixes the through holes evenly distributed on the hoop plate with multiple anchor bars implanted in the concrete column for fixing. At the same time, by removing the outer concrete protective layer of the existing reinforced concrete column or concrete beam, the newly added hoop is embedded in the existing concrete column, which greatly increases the connection strength and stability between the hoop and the existing concrete column and beam, and effectively increases the shear resistance and load-bearing capacity of the newly added beam.

[0027] The node connection device provided by the present invention connects the steel bars of the newly added beam to the extended connection device through a steel corbel-type extended connection device, thereby avoiding various restrictions on the position, quantity and diameter of the newly added steel bars caused by the steel bars in the existing concrete columns or concrete beams, and the position of the steel bars can be set arbitrarily according to specific needs while meeting the requirements of technical specifications.

[0028] At the same time, the node connection device forms an annular integral force-bearing structure connected to the newly added beam in the circumferential direction of the hoop, which can effectively reduce the pulling effect of the newly added beam on the newly added surface, so that the gravity and shear force of the newly added beam are effectively dispersed. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the three-dimensional structure of a node connection device in a preferred embodiment of the present invention.

[0030] Figure 2 for Figure 1 Schematic diagram of the top view structure.

[0031] Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure along the AA direction.

[0032] Figure 4 for Figure 2 Schematic diagram of the cross-sectional structure along direction BB.

[0033] Figure 5 for Figure 2 Schematic diagram of the cross-sectional structure along the B'-B' direction.

[0034] Figure 6 It is a schematic diagram of the three-dimensional structure of a node connection device in a preferred embodiment of the present invention.

[0035] Figure 7 It is a schematic diagram of the three-dimensional structure when the node connection device between two beams is connected.

[0036] Figure 8 This is a schematic diagram of the three-dimensional structure after the node connection device between the two beams is installed.

[0037] Fig. 9 It is a schematic diagram of the three-dimensional structure of a node connection device in a preferred embodiment of the present invention.

[0038] Among them, 1, hoop; 2, horizontal connecting device; 3, vertical connecting device; 4, longitudinal extension device; 5, anchoring reinforcement; 6, cantilever beam; 21, top plate; 22, bottom plate; 31, main vertical plate; 32, side vertical plate; 41, longitudinal reinforcement; 42, stirrups; 61, fixing device; KZ1, existing column; KL1, existing beam; KL2, new beam. DETAILED DESCRIPTION

[0039] In the following description of the present invention, it should be noted that terms such as "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and "vertical" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and therefore, should not be understood as limiting the present invention.

[0040] In the following description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In addition, in the following description of the present invention, unless otherwise specified, “plurality”, “multiple groups”, and “multiple roots” mean two or more.

[0042] Unless otherwise specified, the materials, reagents, devices, equipment, methods and control processes used in the following examples are common materials, reagents, devices, equipment, methods and control processes in the art, and those skilled in the art can obtain them through commercial channels, or can be routinely configured according to specific needs without the need for creative work.

[0043] In the following embodiments, the chemical anchoring connecting steel bar (i.e., anchor bar) added between the steel hoop and the original frame column should be HRB335 or HRB400 ribbed steel bars, or Q235 or Q345 steel screws, and its strength index should comply with the provisions of the current national standard "Code for Design of Concrete Structures" (GB50010-2002). The diameter of the anchor bar should be determined by calculation, and generally should not be less than 12 mm, nor should it be greater than 16 mm. Too large a diameter will increase the difficulty of planting the bar construction;

[0044] At the same time, in order to increase the out-of-plane stiffness of the steel sleeve combined steel plate and prevent the steel plate from bending and deforming out of the plane, which may cause cracks in the beam-column connection nodes, the steel plate thickness should be no less than 10 mm. To improve the safety of the node connection, all butt welds between steel plates should be fully welded. The weld quality grade should be level one when under tension and level two when under compression.

[0045] The present invention is further described below in conjunction with specific embodiments, but the present invention is not limited by the embodiments.

[0046] Example 1

[0047] Figure 1-5 A node connection device for adding a reinforced concrete beam to an existing reinforced concrete column is provided. Specifically, Figure 1 Schematic diagram of the three-dimensional structure of the node connection device in this embodiment. Figure 2 for Figure 1 Schematic diagram of the top view structure. Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure along the AA direction. Figure 4 for Figure 2 Schematic diagram of the cross-sectional structure along direction BB. Figure 5 for Figure 2 Schematic diagram of the cross-sectional structure along the B'-B' direction. Figure 1 For the convenience of observation and display, the feature that the thickness of the existing reinforced concrete column is weakened at the connection of the node connection device so that the node connection device can be nested into the concrete column is not shown.

[0048] from Figure 1-5 It can be seen that the node connection device is a node connection device for adding reinforced concrete beams in four directions on the square reinforced concrete column KZ1. The node connection device includes four steel hoops 1 nested and enclosed on the existing reinforced concrete column with the outer concrete protective layer peeled off, a horizontal connection device 2, a vertical connection device 3, a longitudinal extension device 4 and a plurality of anchor bars 5. Among them, the four steel hoops 1 are welded and fixed to form a whole, and circular through holes (such as Figure 3-5 ). The anchor bar 5 is implanted into the existing reinforced concrete column through the circular through hole. The function of the anchor bar 5 is to fix the steel sleeve 1. At the same time, since the concrete protective outer layer of the existing reinforced concrete column at the connection part needs to be peeled off before installation, the peeling depth is not less than the thickness of the steel sleeve 1, so that the unpeeled concrete protective outer layer can have a certain supporting effect on the steel sleeve 1.

[0049] A connection structure consisting of a horizontal connection device 2 and a vertical connection device 3 in the form of a bullhorn leg is provided on the outer side of the steel hoop 1. Among them, the horizontal connection device 2 is divided into a top plate 21 and a bottom plate 22, and there are four top plates 21 and four bottom plates 22. The top plate 21 is an isosceles trapezoidal structure, and the edges of the four top plates 21 on the same horizontal plane are welded together, so that the four top plates 21 form an integrated annular structure, thereby improving the ability of each side to resist the shear force of the newly added concrete beam. A main vertical plate 31 is welded and fixed to the lower surface of the top plate 21 and the middle of the upper surface of the bottom plate 22, and a side vertical plate 32 is provided on both sides of the main vertical plate 31. Among them, the side vertical plates 32 on three sides are only connected to the lower surface of the top plate 21, and the side vertical plate 32 on the other side is simultaneously connected to the lower surface of the top plate 21 and the upper surface of the bottom plate 22 (such as Figure 3-5 shown).

[0050] A longitudinal extension device 4 is welded and fixed on the upper surface of the top plate 21 and the lower surface of the bottom plate 22. At the same time, the longitudinal extension device 4 is also fixedly connected to the main vertical plate 31 and the side vertical plate 32. The longitudinal connection device 4 is mainly a parallel steel longitudinal rib 41. In order to maintain the stability of the longitudinal rib 41, a steel stirrup 42 is also provided to bundle the longitudinal rib 41. This is to facilitate pouring concrete into the steel cage formed by the longitudinal rib 41 and the stirrup 42 to form a newly added reinforced concrete beam.

[0051] Example 2

[0052] Figure 6-8 A node connection device for adding a reinforced concrete beam between existing reinforced concrete beams is provided. Specifically, Figure 6 Schematic diagram of the three-dimensional structure of the node connection device in this embodiment. Figure 7 It is a schematic diagram of the three-dimensional structure when the node connection device between two beams in this embodiment is connected. Figure 8 It is a schematic diagram of the three-dimensional structure after the node connection device between two beams in this embodiment is installed.

[0053] from Figure 6-8 It can be known that the node connection device includes a steel hoop 1 enclosing an existing reinforced concrete beam KL1, and a horizontal and vertical connection structure similar to the top plate 21, bottom plate 22, main vertical plate 31 and side vertical plate 32 shorter than the main vertical plate 31 is provided on one side of the hoop 1 where the newly added concrete beam KL2 is to be added. The top plate 21, bottom plate 22, main vertical plate 31 and side vertical plate 32 are provided. The difference is that the top plate 21 is a rectangular connecting plate with the same shape as the bottom plate 22. The above-mentioned connection structure is correspondingly provided on the two existing parallel and opposite reinforced concrete beams KL1 where the newly added reinforced concrete beams are to be added. The longitudinal ribs 21 are welded on the connection structure to form a frame structure for pouring concrete, and after the concrete is poured, a newly added reinforced concrete beam (such as Figure 8 ).

[0054] Example 3

[0055] Fig. 9 A node connection device for adding a cantilever beam at the junction of an existing reinforced concrete beam and a concrete column is provided. Specifically, Fig. 9 FIG. 1 is a schematic diagram of the three-dimensional structure of the node connection device in this embodiment. Fig. 9 It can be known that the node connection device is to add a cantilever beam at the intersection of the existing reinforced concrete beam and the concrete column. The connection structure at the node is similar to the connection structure shown in Example 1. The difference is: First, the vertical connection device 3 is only provided on one side of the newly added cantilever beam, and the vertical connection device is only provided with a main vertical plate 31. Through holes are provided on the main vertical plate 31, and are fixedly connected to the corresponding through holes provided on the vertical surface of the I-shaped steel beam serving as the cantilever beam by bolts and other connecting parts. At the same time, the upper surface of the I-shaped cantilever beam 6 is welded and fixed to the lower surface of the top plate 21, and the lower surface is welded and fixed to the upper surface of the bottom plate 22 (the upper and lower surfaces of the main vertical plate 31 are not fixed to the horizontal connection device).

[0056] Example 4

[0057] This embodiment provides a method for adding a reinforced concrete beam to an existing reinforced concrete column using the node connection device described in Embodiment 1. The steps of the method are as follows:

[0058] 1) Remove the concrete protective layer on the four sides of the existing reinforced concrete column where the reinforced concrete beam or cantilever beam is to be newly added, exposing the existing column longitudinal reinforcement and stirrups; the thickness of the peeled protective layer should not be less than the thickness of the steel hoop, so that the unpeeled bottom part can support the steel hoop;

[0059] 2) Calculate the number and diameter of anchor bars to be implanted in the newly added reinforced concrete beams, and implant the anchor bars using the chemical implantation method based on the calculation results; when implanting, try to avoid conflicts with the longitudinal reinforcement and transverse stirrups in the existing columns;

[0060] 3) installing a steel hoop sleeve provided with a through hole corresponding to the position of the anchor bar in step (2) on the newly added reinforced concrete beam, and welding the adjacent hoop sleeve plates together, and then welding each anchor bar to the steel hoop sleeve; wherein the thickness of the steel hoop sleeve is not less than 10 mm;

[0061] 4) Weld the horizontal connection device and the vertical connection device on the outside of the steel hoop;

[0062] 5) welding the longitudinal reinforcement of the newly added reinforced concrete column to the horizontal connection device and the vertical connection device described in step (4), and fixing the longitudinal reinforcement with stirrups;

[0063] 6) Use high-strength non-shrinkage concrete grouting material to fill and compact the gap between the steel sleeve and the existing column;

[0064] 7) Pour concrete for the newly added beams.

[0065] The above method was actually applied in the atrium reinforcement and reconstruction project of Tongnan Ge State Banquet Hotel in Harbin. After the construction was completed, the deflection of the newly added beam and the residual deflection percentage after unloading were measured. The results were 1.194mm and 8.8%, respectively, which were less than the technical requirements of 22.25mm (L / 400) and 15%, respectively. In addition, no cracks appeared in the newly added beams and floor slabs. This shows that the structural bearing capacity of the newly added beams by this method meets the standard and can meet the load requirements for use.

[0066] It should be noted that, in addition to the structures disclosed in the above specific embodiments, those skilled in the art can make adaptive adjustments to the structure of the node connection device according to specific working conditions. For example, for a circular column, the steel hoop sleeve 1 can be adjusted to a circular shape.

[0067] Although the present invention has been disclosed as above in the preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A node connection device for adding a new beam to an existing reinforced concrete column beam, characterized in that: The invention comprises a hoop (1) nested and enclosed at the outer periphery of the connection of an existing reinforced concrete column or concrete beam, a horizontal connection device (2) and a vertical connection device (3) fixedly connected to the hoop (1), an anchor bar (5), and a newly added beam support structure fixedly connected to the horizontal connection device (2) and the vertical connection device (3); the hoop (1) is provided with a plurality of through holes, and the anchor bar (5) passes through the through holes and is fixed to the existing reinforced concrete column or concrete beam; the hoop (1) is fixed along the outer periphery of the existing reinforced concrete column or concrete beam to form a whole; the horizontal connection device (2) comprises a plurality of horizontally arranged top plates (21) and bottom plates (22); the plurality of top plates (21) are in the same horizontal plane and their edges are welded and fixed; the outer surface of the hoop (1) is not higher than the outer surface of the existing reinforced concrete column. The vertical connection device (3) is located between the top plate (21) and the bottom plate (22), and the vertical connection device (3) comprises a main vertical plate (31) welded and fixed to the lower surface of the top plate (21) and the upper surface of the bottom plate (22), and side vertical plates (32) located on both sides of the main vertical plate (31) and fixedly connected to at least the lower surface of the top plate (21); the newly added beam support structure is a longitudinal steel bar device (4) fixedly connected to the upper surface of the top plate (21), the lower surface of the bottom plate (22), and the side surfaces of the main vertical plate (31) and the side vertical plates (32); the anchor bar (5) is implanted and anchored on the existing reinforced concrete column or concrete beam through the through holes evenly arranged on the hoop (1); or is welded and fixed to the steel bars in the existing reinforced concrete column or concrete beam through the through holes arranged on the hoop (1).

2. A node connection device for adding a new beam to an existing reinforced concrete column beam according to claim 1, characterized in that: The plurality of top plates (21) are located on the same horizontal plane and their edges are welded and fixed to form an annular structure.

3. A method for constructing a newly added reinforced concrete beam using the node connection device according to any one of claims 1-2, characterized in that: Here are the steps: (1) Remove the concrete protective layer on all four sides of the existing reinforced concrete column where the reinforced concrete beam or cantilever beam is to be newly added, exposing the existing column longitudinal reinforcement and stirrups; (2) Calculate the number and diameter of anchor bars to be implanted in the newly added reinforced concrete beams, and implant the anchor bars using the chemical implantation method based on the calculation results; (3) installing a steel hoop with a through hole corresponding to the position of the anchor bar in step (2) on the newly added reinforced concrete beam, welding the adjacent hoop plates together, and then welding each anchor bar to the steel hoop; (4) Welding the horizontal connection device and the vertical connection device on the outside of the steel hoop; (5) Welding the longitudinal reinforcement of the newly added reinforced concrete column to the horizontal connection device and the vertical connection device described in step (4), and fixing the longitudinal reinforcement with stirrups; (6) Use high-strength non-shrinkage concrete grouting material to fill and compact the gap between the steel sleeve and the existing column; (7) Pour concrete for the newly added beams.

4. The method according to claim 3, characterized in that The thickness of the steel hoop is not less than 10 mm.

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