Reinforcing structure for reinforcing nodes in concrete frame
By pasting CFRP-UHPC prefabricated plates at the corners of beams and columns of nodes within the concrete frame and anchoring them with CFRP hoops, the problem of difficulty in reinforcement of irregular surface nodes in the prior art is solved, and the bending and shear bearing capacity is significantly improved, and it is suitable for multiple space nodes.
Patent Information
- Application Number
- CN202420590231.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-26
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-03-26
AI Technical Summary
The prior art is difficult to effectively reinforce the nodes in concrete frames, especially in irregular reinforcement surfaces and complex reinforcement surfaces, resulting in poor seismic reinforcement effect.
The CFRP-UHPC prefabricated plate reinforced structure is adopted. By pasting the CFRP-UHPC prefabricated plate at the corners of the beam and column, and anchoring with the CFRP hoop, the bending and shear bearing capacity are enhanced.
It improves the bending bearing capacity and shear bearing capacity of nodes in the concrete frame, has stronger applicability, safety and durability, and is suitable for nodes in various spaces.
Smart Images
Figure CN222632901U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of reinforcing nodes in a concrete frame, and particularly relates to a reinforcing structure for reinforcing nodes in a concrete frame. Background Art
[0002] Reinforced concrete structure (RC frame structure) refers to a structure made of concrete reinforced with steel bars. The main load-bearing components are made of reinforced concrete. It includes thin shell structures, large formwork cast-in-place structures, and reinforced concrete structures built using slipforms, lifting plates, etc. A structure made of steel bars and concrete. The steel bars bear tension and the concrete bears pressure. It has the advantages of being strong, durable, fireproof, saving steel and low cost compared to steel structures.
[0003] RC frame structures are widely used in large quantities. In the context of increasingly tight construction resources, energy conservation and emission reduction, and urban green renewal, it is necessary to diagnose and reinforce their internal nodes, which is a strategic requirement for achieving sustainable development in the construction industry. The beams around the nodes in the frame play a restraining role, which is relatively safe. However, when encountering a relatively large horizontal earthquake, the large shear force will cause shear failure in the core area. In addition, many buildings do not meet the current seismic design specifications and have the defect of insufficient seismic performance, which urgently needs to be reinforced.
[0004] In order to effectively improve the seismic reinforcement effect of the internal nodes of the RC frame structure, it is necessary to use the reinforcement structure to effectively reinforce the internal nodes. At present, the main methods for reinforcing the internal nodes of the RC frame include increasing the cross-section, external steel and external fiber composite materials. Although this method has achieved good seismic reinforcement effects in actual engineering applications, the above reinforcement methods are only applicable to relatively regular reinforcement surfaces, and it is difficult to effectively reinforce irregular reinforcement surfaces. The internal nodes of the RC frame are limited by the complexity of their reinforcement surfaces, and it is difficult to achieve effective reinforcement of their internal nodes. Therefore, the applicability and practical application value of the above reinforcement methods are both insufficient to a certain extent. Utility Model Content
[0005] In order to effectively improve the seismic reinforcement effect of nodes within an RC frame, the utility model provides a reinforcement structure for reinforcing nodes within a concrete frame.
[0006] A technical solution of a reinforcement structure for reinforcing nodes in a concrete frame of the utility model is as follows:
[0007] A reinforcement structure for reinforcing a node in a concrete frame, characterized in that it comprises a reinforcement structure body arranged at a node position in a reinforced concrete structure;
[0008] The reinforcement structure body includes a CFRP-UHPC prefabricated panel used to fit tightly at the corners around the beams and columns. The upper end of the CFRP-UHPC prefabricated panel fits with the top plate installed on the beams and columns, the two side surfaces of the CFRP-UHPC prefabricated panel fit with the peripheral beams installed on the beams and columns, and the lower end of the CFRP-UHPC prefabricated panel is anchored to the beams and columns through a CFRP hoop.
[0009] Furthermore, the inner surface of the CFRP-UHPC prefabricated panel is arranged at the corners around the beams and columns through a groove bonding structure.
[0010] Furthermore, the groove bonding structure includes at least one groove, the groove is opened at the corner of the beam and column, and is spaced apart along the length direction of the beam and column, an epoxy resin structural adhesive is arranged in the groove, a structural adhesive bonding layer is arranged between the inner surface of the CFRP-UHPC prefabricated panel and the beam and column, and the structural adhesive bonding layer is connected to the epoxy resin structural adhesive.
[0011] Furthermore, the groove is opened at the corner of the beam column and is inclined upward, and the inclination angle is 30-45 degrees.
[0012] Furthermore, the CFRP-UHPC prefabricated panel comprises an overall L-shaped UHPC prefabricated panel, and CFRP reinforcements extending along the length direction of the UHPC prefabricated panel are respectively arranged inside two panel surfaces of the UHPC prefabricated panel.
[0013] Furthermore, the height of the UHPC prefabricated panel is 1.5 times the cross-sectional height of the peripheral beams, the thickness of the UHPC prefabricated panel is twice the thickness of the CFRP reinforcement diameter, and the thickness of the UHPC prefabricated panel is not less than 15 mm.
[0014] Furthermore, the UHPC prefabricated board is made by uniformly mixing cement, silica fume, quartz sand, quartz powder, water, water reducing agent and steel fiber, and the material mix ratio is 0.2-0.22 kg of silica fume, 0.18-0.22 kg of quartz powder and 1.5% water reducing agent per 1 kg of cement, wherein the sand-binder ratio is 1.0-1.2, the water-binder ratio is 0.18-0.22, and the volume content of the steel fiber is 2%.
[0015] Furthermore, the CFRP hoop is formed by circumferentially wrapping CFRP cloth, the cloth height is 0.5 times the cross-sectional height of the surrounding beam, the thickness is 2 mm, and three layers are wrapped circumferentially along the column body of the beam column.
[0016] The utility model discloses a reinforcement structure for reinforcing nodes in a concrete frame. The overall design of the reinforcement structure is reasonable, the structure is simple, and the construction is convenient. By pasting CFRP-UHPC prefabricated panels at the corners of beams and columns, the bending bearing capacity of the upper ends of beams and columns and the shear bearing capacity of nodes are effectively improved. Moreover, compared with the traditional method of increasing the cross-section, the steel-bonding reinforcement method has stronger applicability, safety, and durability, and is convenient and reliable to construct. It can be applied to various nodes in space by controlling the thickness of the CFRP-UHPC prefabricated panels and the diameter of the CFRP reinforcement. This solves the problem that the concrete frame node reinforcement method and the reinforcement structure in the prior art are not practical when used for nodes in space. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 The utility model is a structural schematic diagram of a reinforcement structure for reinforcing nodes in a concrete frame.
[0018] Figure 2 The utility model is a structural schematic diagram of a reinforcement structure for reinforcing nodes in a concrete frame after grooves are opened.
[0019] Figure 3 It is a cross-sectional view of a reinforcement structure for reinforcing nodes in a concrete frame after a groove is opened according to the utility model.
[0020] Figure 4 The utility model is a structural schematic diagram of a reinforcement structure for reinforcing a node in a concrete frame after installing a CFRP-UHPC prefabricated panel.
[0021] Figure 5 It is a structural schematic diagram of a CFRP-UHPC prefabricated panel of the utility model for reinforcing a reinforced structure of a node within a concrete frame.
[0022] Figure 6 It is a top view of a CFRP-UHPC prefabricated panel of the utility model, which is a reinforcement structure for reinforcing nodes in a concrete frame.
[0023] Figure 7 The utility model is a structural schematic diagram of a CFRP hoop of a reinforcement structure for reinforcing a node in a concrete frame. DETAILED DESCRIPTION
[0024] The utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the utility model will become clearer according to the following description and claims. It should be noted that the drawings are all in a very simplified form and are not in precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model.
[0025] Example 1
[0026] refer to Figures 1 to 7 The reinforcement structure of this embodiment is used to reinforce the nodes in a concrete frame, and is characterized by comprising a reinforcement structure body 400 arranged at the node position in the reinforced concrete structure.
[0027] The reinforcement structure body 400 includes a CFRP-UHPC prefabricated panel 410 for tightly fitting around the corners of the beam column 100. The upper end of the CFRP-UHPC prefabricated panel 410 fits with the top plate 300 installed on the beam column 100, and the two side surfaces of the CFRP-UHPC prefabricated panel 410 fit with the peripheral beam 200 installed on the beam column 100. The lower end of the CFRP-UHPC prefabricated panel 410 is anchored to the beam column 100 through a CFRP hoop 420.
[0028] As a preferred embodiment, the inner surface of the CFRP-UHPC prefabricated panel 410 is arranged at the corners around the beam column 100 through a groove bonding structure 430 .
[0029] As a preferred embodiment, the groove bonding structure 430 includes at least one groove 431, which is opened at the corner of the beam column 100 and is spaced apart along the length direction of the beam column 100. An epoxy resin structural adhesive is provided in the groove 431, and a structural adhesive bonding layer is provided between the inner surface of the CFRP-UHPC prefabricated panel 410 and the beam column 100, and the structural adhesive bonding layer is connected to the epoxy resin structural adhesive.
[0030] By obliquely opening the groove 431 in the column body of the beam column 100, an effect similar to a shear groove is formed, thereby enhancing the bonding between the CFRP-UHPC precast panel 410 and the concrete section, and can effectively avoid debonding in extreme cases. Compared with the traditional EBROG technology with horizontal grooves, it can provide stronger bonding strength, and in combination with the CFRP hoop 420, it has a stronger anchoring effect, better durability and economy, and a wider range of applications.
[0031] As a preferred embodiment, the groove 431 is opened at the corner of the beam column and tilted upward, and the tilt angle is 30-45 degrees. The length of the groove 431 is the difference between the cross-section width of the beam column 100 and the column body, and the width is recommended to be 8-10mm.
[0032] As a preferred embodiment, the CFRP-UHPC prefabricated panel 410 includes an L-shaped UHPC prefabricated panel 411 as a whole, and CFRP reinforcements 412 extending along the length direction are respectively provided inside the two panel surfaces of the UHPC prefabricated panel 411. The height of the L-shaped UHPC prefabricated panel 411 as a whole is 1.5 times the effective height of the cross-section of the peripheral beam.
[0033] The selection of CFRP reinforcement 412 needs to be determined according to the actual stress conditions. The diameter of CFRP reinforcement 412 ranges from 8 to 10 mm, and the length is the same as that of UHPC prefabricated plate 411. One reinforcement is arranged on each side of L-shaped UHPC prefabricated plate 411.
[0034] As a preferred embodiment, the height of the UHPC prefabricated panel 411 is 1.5 times the cross-sectional height of the peripheral beam 200, and the thickness of the UHPC prefabricated panel 411 is twice the diameter of the CFRP reinforcement 412. The thickness of the UHPC prefabricated panel 411 is not less than 15 mm.
[0035] As a preferred embodiment, the UHPC prefabricated board 411 is made by uniformly mixing cement, silica fume, quartz sand, quartz powder, water, water reducing agent and steel fiber, and the material mix ratio is 0.2-0.22 kg of silica fume, 0.18-0.22 kg of quartz powder and 1.5% water reducing agent per 1 kg of cement, wherein the sand-binder ratio is 1.0-1.2, the water-binder ratio is 0.18-0.22, and the volume content of steel fiber is 2%. The materials for making the UHPC prefabricated board are not limited to the above-mentioned materials and ratios, and only the requirements of strength, construction workability, durability, etc. need to be met, and no restriction is made on this.
[0036] As a preferred embodiment, the CFRP hoop 412 is formed by circumferentially wrapping CFRP cloth material, the cloth material height is 0.5 times the cross-sectional height of the surrounding beam, the thickness is 2 mm, and three layers are wrapped circumferentially along the column body.
[0037] The construction steps of the reinforcement structure in this application are as follows:
[0038] S1: A groove 431 is excavated along the beam axis in the core area of the node to be reinforced;
[0039] S2: prefabricate and install CFRP-UHPC prefabricated panels 410;
[0040] S3: Anchor the reinforced end using the CFRP hoop 420 .
[0041] The specific process is as follows:
[0042] In S1, the position and size of the groove are determined according to the size of the node to be reinforced and the distribution of reinforcement: along the axis of the beam, a main groove is excavated at the column position corresponding to the center line of the CFRP-UHPC precast panel, and the remaining grooves are arranged in parallel along the height of the beam, and the center distance between adjacent main grooves is 80-120mm; the main groove is cut into an L-shaped groove along the axis of the beam, and the length of the two grooves is the difference in width of the beam-column section. The width is recommended to be 8-10mm, and the depth is 1.5 times the width of the surrounding beams. It is arranged at an oblique angle along the column axis with an inclination angle of 30-45°.
[0043] The method of cutting the groove is: first determine the groove position manually, then use a cutting machine or other related tools to cut the groove on the surface of the column, and roughen the groove so that the concrete and structural adhesive can fully bite.
[0044] Clean the channel: first use an air pump to remove all gravel and floating dust, then use clean water to repeatedly rinse the inner wall of the channel, especially the uneven parts of the inner wall, and completely remove all floating dust until the water is dry.
[0045] In S2, the groove 4 is filled with epoxy resin structural adhesive; after the colloid in the groove solidifies, the structural adhesive is brushed on the area to be reinforced, and the CFRP-UHPC prefabricated panel is firmly adhered to the area.
[0046] In S3, the CFRP hoop is made of CFRP cloth wrapped in a circumferential direction. The cloth height is 0.5 times the cross-sectional height of the surrounding beam and the thickness is 2 mm. Structural adhesive is used to wrap three layers around the column.
[0047] The production steps of CFRP-UHPC prefabricated panels are as follows:
[0048] A1: Determine the shape and size of the UHPC prefabricated panel according to the size of the node to be reinforced and the distribution of reinforcement;
[0049] A2: Make the corresponding mold and arrange two CFRP bars along the column axis;
[0050] A3: Pour the evenly mixed UHPC material into the mold.
[0051] In order to better illustrate and understand the reinforcement structure and reinforcement method of the internal node of the existing concrete frame structure provided in this embodiment, the specific size and manufacturing and installation process of a reinforcement structure are given as an example below and described in detail. It should be understood that the specific size and manufacturing and installation process of the reinforcement structure are only used for illustration and are not used to limit the protection scope of the utility model.
[0052] Taking the reinforcement and renovation of an existing frame structure of a hospital as an example, a certain internal node is selected as a sample for reinforcement:
[0053] Node size: The cross-sectional size of the peripheral beams is 250×600mm, the cross-sectional size of the beam-columns is 600×700mm, and the peripheral beams and beam-columns are aligned with a difference of 175mm.
[0054] Node performance: This building is a reconstruction and reinforcement of an existing frame structure. The original frame structure has been used for many years, and the function of some space buildings has changed. The bearing capacity of the existing frame nodes cannot meet the requirements of the new structure, and it is accompanied by demolition work, so it is necessary to reinforce the nodes. Among them, the nodes in the frame are subject to complex forces and urgently need to be reinforced.
[0055] Reinforcement solution:
[0056] According to the size of the nodes to be reinforced and the reinforcement conditions, it is necessary to prefabricate 4 pairs of CFRP-UHPC prefabricated panels, whose geometric dimensions are as follows: the UHPC prefabricated panel is 900mm high, 40mm thick, and the first and second side lengths are both 175mm; 8 CFRP bars are required, with a diameter of 10mm and a length of 900mm, which are arranged in the middle of the first and second side lengths of the corresponding panels.
[0057] According to the size of the reinforcement node and the reinforcement conditions, 3 grooves need to be cut at the corners of the upper ends of the beams and columns, a total of 12 grooves, with a width of 10mm and a depth of 15mm, and an angle of 30°-45° with the axis of the beams and columns. Along the axis of the beams and columns, take the column body corresponding to the centerline of the CFRP-UHPC prefabricated panel to cut grooves, and arrange two grooves in parallel with an interval of 100mm. Use cutting machines and other related tools to cut the grooves, roughen the inner wall of the grooves, and clean them.
[0058] Clean the surface of the area to be reinforced to ensure it is smooth and flat. Apply structural glue to the surface of the area to be reinforced, fill the groove with epoxy resin structural glue, and install the CFRP-UHPC prefabricated panels.
[0059] The CFRP-UHPC prefabricated panels located below the beam body of the peripheral beam are circumferentially wrapped with CFRP cloth to form CFRP hoop anchors, and the column body and the CFRP-UHPC prefabricated panels are tightly bonded using epoxy resin structural adhesive.
[0060] The reinforcement structure of the present embodiment is used to reinforce the nodes in the concrete frame. The overall design of the reinforcement structure is reasonable, the structure is simple, and the construction is convenient. By pasting CFRP-UHPC prefabricated panels at the corners of beams and columns, the bending bearing capacity of the upper ends of beams and columns and the shear bearing capacity of nodes are effectively improved. In addition, compared with the traditional method of increasing the cross-section, the steel bonding reinforcement method has stronger applicability, safety and durability, and is convenient and reliable to construct. It can be applied to various nodes in space by controlling the thickness of the CFRP-UHPC prefabricated panels and the diameter of the CFRP reinforcement. It solves the problem that the concrete frame node reinforcement method and reinforcement structure in the prior art are not practical when used for nodes in space.
[0061] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art based on the above disclosure shall fall within the scope of protection of the claims.
Claims
1. A reinforcement structure for reinforcing nodes in a concrete frame, characterized in that: It includes a reinforcement structure body (400) arranged at a node position in a reinforced concrete structure; The reinforcement structure body (400) comprises a CFRP-UHPC prefabricated plate (410) for tightly fitting around the corners of the beam column (100); the upper end of the CFRP-UHPC prefabricated plate (410) fits with the top plate (300) installed on the beam column (100); the two side surfaces of the CFRP-UHPC prefabricated plate (410) fit with the peripheral beam (200) installed on the beam column (100); and the lower end of the CFRP-UHPC prefabricated plate (410) is anchored to the beam column (100) through a CFRP hoop (420).
2. The reinforcement structure for reinforcing nodes in a concrete frame according to claim 1, characterized in that: The inner surface of the CFRP-UHPC prefabricated plate (410) is arranged at the corners around the beam column (100) through a channel bonding structure (430).
3. The reinforcement structure for reinforcing nodes in a concrete frame according to claim 2, characterized in that: The groove bonding structure (430) comprises at least one groove (431), wherein the groove (431) is provided at a corner of the beam column (100) and is spaced apart along the length direction of the beam column (100), an epoxy resin structural adhesive is provided in the groove (431), a structural adhesive bonding layer is provided between the inner surface of the CFRP-UHPC prefabricated panel (410) and the beam column, and the structural adhesive bonding layer is connected to the epoxy resin structural adhesive.
4. The reinforcement structure for reinforcing nodes in a concrete frame according to claim 3, characterized in that: The groove (431) is opened at the corner of the beam column (100) and is inclined upward, and the inclination angle is 30-45 degrees.
5. The reinforcement structure for reinforcing nodes in a concrete frame according to claim 1, characterized in that: The CFRP-UHPC prefabricated plate (410) comprises an overall L-shaped UHPC prefabricated plate (411), and CFRP reinforcements (412) extending along the length direction of the UHPC prefabricated plate (411) are respectively arranged inside two plate surfaces of the UHPC prefabricated plate (411).
6. The reinforcement structure for reinforcing nodes in a concrete frame according to claim 5, characterized in that: The height of the UHPC prefabricated plate (411) is 1.5 times the cross-sectional height of the peripheral beam (200), and the thickness of the UHPC prefabricated plate (411) is twice the diameter of the CFRP reinforcement (412). The thickness of the UHPC prefabricated plate (411) is not less than 15 mm.
7. The reinforcement structure for reinforcing nodes in a concrete frame according to claim 5, characterized in that: The CFRP hoop (420) is formed by wrapping CFRP cloth in a circumferential direction. The cloth height is 0.5 times the cross-sectional height of the surrounding beams and the thickness is 2 mm. Three layers are wrapped in a circumferential direction along the column body.