Modular reinforcing structure of existing concrete beam and construction method

Abstract

The invention relates to a modular reinforcing structure of an existing concrete beam, which comprises a prefabricated concrete outer skin reinforcing structure used for wrapping an original concrete beam body, the concrete strength grade of the outer skin reinforcing structure is not lower than C30, the thickness of the outer skin reinforcing structure is not smaller than 60mm, longitudinal bars are arranged at the upper part and the bottom of the outer skin reinforcing structure, and waist bars are arranged in the middle of the outer skin reinforcing structure; open stirrups are arranged outside the longitudinal bars and the waist bars, and HRB400-level steel bars are selected as the steel bars. The surface layer of an original concrete beam body is removed until stirrups and longitudinal bars are exposed, and the exposed longitudinal bars and stirrups are subjected to rust removal treatment; and the high-strength fine aggregate concrete is used for filling a cavity between the prefabricated concrete skin reinforcing structure and the original concrete beam body and connecting the prefabricated concrete skin reinforcing structure and the original concrete beam body into a whole. As a template for post-pouring high-strength fine aggregate concrete, the template disclosed by the invention reduces the on-site template erecting and removing time, improves the construction efficiency, reduces the high-altitude template erecting operation and improves the construction safety.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of prefabricated buildings, in particular to a modular reinforcing structure for existing concrete beams and a construction method. BACKGROUND

[0002] In the field of construction engineering, the reinforcement of concrete beams is an important technical link. With the increase of building service life and the improvement of load requirements, many existing concrete beams need to be reinforced to meet safety and use requirements. In the traditional concrete beam reinforcement method, the enlarged section reinforcement method is a commonly used technical means. This method increases the cross-sectional area of the original component and adds steel bars to improve its carrying capacity and stiffness. However, although the enlarged section reinforcement method can meet the reinforcement requirements to some extent, it still has many limitations in practical application.

[0003] The specific implementation of the traditional concrete beam enlarged section reinforcement method includes two methods: bridge deck reinforcement layer reinforcement method and enlarged main beam section method. The bridge deck reinforcement layer reinforcement method is to re-pour a layer of reinforced concrete reinforcement layer after treating the old bridge deck; while the enlarged main beam section reinforcement method is to increase the cross-sectional area of the T-beam and add ordinary steel bars to improve the carrying capacity. However, these methods have exposed the following problems in practical application: Firstly, the long construction period is a significant disadvantage of the traditional enlarged section reinforcement method. This method requires a series of concrete construction related procedures such as formwork, vibration, pouring, curing, etc. These steps are not only cumbersome, but also time-consuming. During the concrete curing period, the load needs to be limited, further prolonging the construction period.

[0004] Secondly, the increase of the self-weight of the structure after reinforcement is also a disadvantage of the traditional method. The enlarged section reinforcement method will increase a new concrete layer on the basis of the original component, resulting in a significant increase in the self-weight of the structure. This not only produces an additional gravity effect on the entire structure, but also may cause the carrying capacity of the newly added part to be reduced, reducing the durability of the structure.

[0005] In addition, the reduction of building use space is another problem that cannot be ignored in the traditional enlarged section reinforcement method. Since reinforcement requires a certain space, the net height and actual use area of the building will be affected to some extent after reinforcement. This is undoubtedly a huge problem for some buildings with high space requirements. SUMMARY

[0006] The present application aims to overcome the defects of the prior art and provide a modular reinforcing structure for existing concrete beams and a construction method, which solves the problems of long construction period, large space occupation area and large amount of formwork support used in the traditional concrete beam enlarged section reinforcement method.

[0007] In order to solve the above technical problems, the present application is implemented as follows: A modular reinforcing structure of an existing concrete beam, characterized in that it comprises: A prefabricated concrete outer skin reinforcing structure for wrapping an original concrete beam body, the concrete strength grade of the outer skin reinforcing structure is not less than C30, the thickness is not less than 60mm, and the upper and bottom parts are provided with longitudinal reinforcement, and the middle position is provided with waist reinforcement, and the longitudinal reinforcement and waist reinforcement are externally provided with open stirrups, and the steel bars are selected from HRB400 grade steel bars; The original concrete beam body, the surface layer of which is removed to expose the stirrups and longitudinal reinforcement, and the exposed longitudinal reinforcement and stirrups are subjected to rust removal treatment; High-strength fine aggregate concrete for filling the cavity between the prefabricated concrete outer skin reinforcing structure and the original concrete beam body, and for connecting the two into a whole, the strength grade of which is higher than that of the original concrete beam body and not less than C30.

[0008] The modular reinforcing structure of an existing concrete beam, characterized in that: the distance between the inner surface of the prefabricated concrete outer skin reinforcing structure and the outer surface of the original beam body is not less than 70mm, and a certain gap is left between the upper surface of the outer skin structure and the floor connected with the original concrete beam for the pouring of high-strength fine aggregate concrete.

[0009] The modular reinforcing structure of an existing concrete beam, characterized in that: the external stirrups of the prefabricated concrete outer skin reinforcing structure are arranged with increased density at both ends according to the design documents and relevant specifications, and the concrete surface inside the prefabricated concrete outer skin reinforcing structure and the outer surface of the original beam body are subjected to chiseling treatment.

[0010] The modular reinforcing structure of an existing concrete beam, characterized in that: the longitudinal reinforcement of the upper and lower parts of the prefabricated concrete outer skin reinforcing structure is anchored into the structural columns on both sides of the beam by taking reliable anchoring measures, to ensure the reliable connection of the prefabricated concrete outer skin reinforcing structure and the original beam body.

[0011] The modular reinforcing structure of an existing concrete beam, characterized in that: the prefabricated concrete outer skin reinforcing structure is designed in a modular manner, which can be adjusted according to concrete beams of different cross-sectional sizes, improving the flexibility and adaptability of the reinforcing structure.

[0012] A construction method of a modular reinforcing structure of an existing concrete beam, characterized in that it comprises the following steps: Prefabricated component production: In the prefabricated component production factory, the prefabricated concrete outer skin reinforcing structure is produced according to the design documents and relevant specification requirements, the concrete strength grade of the prefabricated concrete outer skin reinforcing structure is not less than C30, the thickness is not less than 60 mm, and longitudinal reinforcement is arranged on the upper and bottom parts, waist reinforcement is arranged in the middle position, and open stirrup reinforcement is arranged outside; Site preparation: The surface layer concrete of the original concrete beam body is removed until the stirrups and longitudinal reinforcement are exposed, and the concrete beam surface is cleaned and rusted; Installation of prefabricated components: The prefabricated concrete outer skin reinforcing structure is installed outside the original beam body, ensuring that the upper surface of the outer skin structure leaves a gap with the floor, and the inner surface of the outer skin reinforcing structure is spaced apart from the outer surface of the original beam body by not less than 70 mm, while supports and adjustable jacks are arranged at the lower part of the outer skin reinforcing structure; Anchoring measures: The upper and lower longitudinal reinforcement of the prefabricated concrete outer skin reinforcing structure is anchored into the structural columns on both sides of the beam; Pouring of high-strength fine aggregate concrete: high-strength fine aggregate concrete is poured into the gap and the cavity between the outer skin reinforcing structure and the original beam body, and the strength grade of the high-strength fine aggregate concrete is higher than that of the newly added concrete outer skin structure and the original beam body; Maintenance and form removal: The high-strength fine aggregate concrete is maintained, and after the strength grade of the fine aggregate concrete reaches 100% of the design strength, the supports and adjustable jacks of the outer skin reinforcing structure are removed.

[0013] The beneficial effects of the application are: through the above technical scheme, the application provides a modular reinforcing structure and construction method for existing concrete beams, which uses prefabricated concrete outer skin reinforcing structures and high-strength fine aggregate concrete poured in the cavity, and realizes rapid and efficient reinforcement construction through modular design. The prefabricated concrete outer skin reinforcing structure is produced in the prefabricated component production factory according to the design documents and relevant specification requirements, which ensures the quality and precision of the reinforcing structure. At the same time, the external stirrups are arranged at both ends of the prefabricated outer skin reinforcing structure according to the design documents and relevant specification requirements, which further improves the bearing capacity and stability of the reinforcing structure.

[0014] Compared with the traditional method of increasing the cross-section reinforcement, the modular reinforcing structure of the application has many advantages. First, this method greatly improves the construction efficiency and shortens the construction period. Since the prefabricated components are produced in the factory, only assembly and pouring work is required on site, thus reducing the wet work time on site. Second, the modular design makes the reinforcing structure more flexible and variable, which can adapt to the reinforcement needs of concrete beams of different sizes and shapes. In addition, this method also reduces material and space occupation, reduces reinforcement cost and the impact on the use function of the building.

[0015] In summary, the modular reinforcement structure of existing concrete beams and the construction method provided by the present application effectively improve the problems of long construction period, increased structure dead weight, reduced building space and the like existing in the traditional reinforcement method. Through the modular design and the application of prefabricated components, fast, efficient and flexible reinforcement construction is realized, thereby providing a new solution for the reinforcement of concrete beams in the field of building engineering.

[0016] The present application has strong practicability, simple principle, high reliability, and the like. The designed modular reinforcement structure of existing concrete beams is poured in a factory according to design documents and specification requirements, and the longitudinal reinforcement of the outer skin structure is connected to the structure columns on both sides of the beam by using sleeve connection and reliable anchoring measures, so that the quality of the prefabricated components is controllable and the construction error on site is reduced. The operation is convenient and the construction efficiency is high. During on-site construction, only the prefabricated concrete outer skin reinforcement structure needs to be installed on the outside of the original beam body, and the outer skin reinforcement structure can be directly used as a formwork, thereby reducing the formwork and demolding time on site, avoiding the welding operation of the original beam body reinforcement, and improving the construction efficiency on site. The present application has strong applicability and high flexibility. The designed modular outer skin reinforcement structure of existing concrete beams can be flexibly adjusted according to different beam body sizes to adapt to diversified reinforcement requirements, enhance the overall structure, and improve the bearing capacity of the beam body. The new and old concrete joint surface is treated by chiseling and supplemented by high-strength fine stone concrete pouring, so that the interface is closely adhered, the bearing capacity and stiffness of the beam body are significantly improved, the material and space occupation are reduced, and the safety risk is reduced. The construction site does not need a traditional formwork fixing system, is suitable for construction sites with limited space, reduces high-altitude formwork operation, simplifies the installation process of prefabricated components, and improves construction safety. BRIEF DESCRIPTION OF DRAWINGS

[0017] The present application will be further described in detail below in combination with the drawings and embodiments: Figure 1 FIG. 1 is a cross-sectional view of a new modular reinforcement structure of existing concrete beams in the embodiment of the present application.

[0018] Figure 2 FIG. 2 is a front view of a new modular reinforcement structure of existing concrete beams in the embodiment of the present application. DETAILED DESCRIPTION

[0019] The technical solutions of the embodiments of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0020] As Figure 1 , 2The utility model shows a modular reinforcing structure of existing concrete beam, characterized in that it comprises: The prefabricated concrete outer skin reinforcing structure 1 is used for wrapping the original concrete beam body 7, the concrete strength grade of the outer skin reinforcing structure is not less than C30, the thickness is not less than 60 mm, and the upper part and the bottom of the outer skin reinforcing structure are provided with upper longitudinal reinforcement 3 and bottom longitudinal reinforcement 2, the middle position is provided with waist reinforcement 4, and the longitudinal reinforcement and the waist reinforcement are externally provided with open stirrup 5; the steel bars are selected from HRB400 grade steel bars; The original concrete beam body 7 is provided with a surface layer removed to expose the stirrups and the longitudinal reinforcement, and the exposed longitudinal reinforcement and the stirrups are subjected to rust removal treatment; The high-strength fine aggregate concrete 6 is used for filling the cavity between the prefabricated concrete outer skin reinforcing structure and the original concrete beam body, and is used for connecting the two into a whole, and the strength grade is higher than that of the original concrete beam body and is not less than C30.

[0021] The distance between the inner surface of the prefabricated concrete outer skin reinforcing structure and the outer surface of the original beam body is not less than 70 mm, and a certain gap is left between the upper surface of the outer skin structure and the floor connected with the original concrete beam for the pouring of the high-strength fine aggregate concrete.

[0022] The outer stirrups of the prefabricated concrete outer skin reinforcing structure are arranged in a dense manner at both end positions according to the design document and the requirements of the relevant specifications, and the concrete surface in the prefabricated concrete outer skin reinforcing structure and the outer surface of the original beam body are subjected to chiseling treatment.

[0023] The longitudinal reinforcement of the upper part and the lower part of the prefabricated concrete outer skin reinforcing structure is anchored into the structural columns on both sides of the beam by taking reliable anchoring measures to ensure the reliable connection of the prefabricated concrete outer skin reinforcing structure and the original beam body.

[0024] The prefabricated concrete outer skin reinforcing structure adopts a modular design, can be adjusted according to concrete beams of different cross-sectional sizes, and improves the flexibility and adaptability of the reinforcing structure.

[0025] A construction method of a modular reinforcing structure of an existing concrete beam comprises the following steps: Step one, in the prefabricated component production factory, the prefabricated concrete outer skin reinforcing structure is produced according to the design document and the requirements of the relevant specifications, the concrete strength grade of the outer skin structure should not be less than C30, the thickness should not be less than 60 mm, longitudinal reinforcement is arranged at the upper part and the bottom of the outer skin reinforcing structure, waist reinforcement is arranged at the middle position, open stirrup is arranged outside the longitudinal reinforcement and the waist reinforcement, the steel bars are preferably selected from HRB400 grade steel bars, the diameter and position of the longitudinal steel bars and the stirrups are determined according to the design document and meet the requirements of the Concrete Structure Design Standard, the Building Seismic Design Standard and the Concrete Structure Reinforcing Design Standard and the like, and the concrete surface in the outer skin reinforcing structure is subjected to chiseling treatment. Step two, remove the original concrete beam body surface layer to expose the stirrups and longitudinal reinforcement, and then clean the gravel, floating slurry, dust and debris on the surface of the concrete beam, and rust the exposed longitudinal reinforcement and stirrups; Step three, install the prefabricated concrete skin reinforcement structure outside the original beam body, leaving a certain gap between the upper surface of the skin structure and the original concrete floor 8 connected to the original concrete beam for the pouring of high-strength fine aggregate concrete, and setting supports and adjustable jacks at the lower part of the skin reinforcement structure. The distance between the inner surface of the skin reinforcement structure and the outer surface of the original beam body should not be less than 70mm; Step four, anchor the upper and lower longitudinal reinforcement of the prefabricated concrete skin reinforcement structure into the structural columns 9 on both sides of the beam by taking reliable anchoring measures 10; Step five, pour high-strength fine aggregate concrete in the cavity, and the poured concrete has a higher strength grade than the newly added concrete skin structure and the original beam body, so that the original concrete beam body and the newly added concrete skin structure form a whole; Step six, maintain the high-strength fine aggregate concrete, and remove the supports and adjustable jacks of the skin reinforcement structure after the fine aggregate concrete reaches 100% design strength.

[0026] In terms of construction efficiency, the technical scheme realizes the convenience and efficiency of on-site construction by using prefabricated concrete skin reinforcement structure. Since the prefabricated components have been produced in the factory, only installation operation is needed on site, greatly reducing the cumbersome procedures such as formwork erection and removal, thereby significantly shortening the construction period. In addition, welding of the original beam body reinforcement is avoided, further improving the construction efficiency.

[0027] In terms of structural performance, the technical scheme ensures the close adhesion between the new and old concrete by roughening the new and old concrete joint surface and supplementing the pouring of high-strength fine aggregate concrete. This treatment not only enhances the integrity of the structure, but also significantly improves the load-carrying capacity and stiffness of the beam, making the reinforced concrete beam have more excellent mechanical properties.

[0028] In terms of cost, the technical scheme improves construction efficiency, reduces material and space occupation, and prefabricated components with controllable quality reduce on-site construction errors, all of which help to reduce construction cost. The improvement of construction efficiency means the saving of manpower, material resources and other resources; the reduction of material and space occupation reduces the cost of material procurement and site rental; and the controllable quality of prefabricated components reduces the additional cost caused by rework or repair.

[0029] In terms of safety, the technical scheme reduces the safety risk in the construction process by reducing the material and space occupation. Without the traditional formwork fixing system, the high-altitude formwork operation is reduced, thereby reducing the probability of occurrence of safety accidents such as high-altitude falling. At the same time, the prefabricated component is poured and completed in the factory, the quality is controllable, the uncertainty and safety hazard in the on-site construction are reduced, and a safer working environment is provided for the construction personnel.

[0030] The above is only an embodiment provided by the present application and is not intended to limit the present application. Although the present application is described in detail with reference to the embodiment, those skilled in the art can still modify the technical solutions described in the foregoing embodiment or make equivalent replacements for some technical features, but any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A modular reinforcement structure for existing concrete beams, characterized in that It includes: A prefabricated concrete outer skin reinforcement structure is used to wrap the original concrete beam body. The concrete strength grade of the outer skin reinforcement structure is not less than C30, the thickness is not less than 60mm, and the upper and lower parts of the outer skin reinforcement structure are provided with longitudinal reinforcement, the middle part is provided with waist reinforcement, and the longitudinal reinforcement and waist reinforcement are provided with open stirrups outside. The steel bars are HRB400 grade steel bars. The surface of the original concrete beam was removed to expose the stirrups and longitudinal bars, and the exposed longitudinal bars and stirrups were rust-removed; High-strength fine stone concrete is used to fill the cavity between the precast concrete outer skin reinforcement structure and the original concrete beam body, and is used to connect the two into a whole. Its strength grade is higher than that of the original concrete beam body and is not lower than C30.

2. The modular reinforcement structure for existing concrete beams according to claim 1, characterized in that: The distance between the inner surface of the prefabricated concrete outer skin reinforcement structure and the outer surface of the original beam body should not be less than 70mm, and a certain gap should be left between the upper surface of the outer skin structure and the floor slab connected to the original concrete beam for pouring high-strength fine stone concrete.

3. The modular reinforcement structure for existing concrete beams according to claim 1, characterized in that: The external stirrups of the prefabricated concrete skin reinforcement structure are densely arranged at both ends in accordance with the requirements of the design documents and relevant specifications, and the concrete surface inside the prefabricated concrete skin reinforcement structure and the outer surface of the original beam body are roughened.

4. The modular reinforcement structure for existing concrete beams according to claim 1, characterized in that: The upper and lower longitudinal reinforcements of the prefabricated concrete outer skin reinforcement structure are anchored into the structural columns on both sides of the beam by reliable anchoring measures to ensure a reliable connection between the prefabricated concrete outer skin reinforcement structure and the original beam body.

5. The modular reinforcement structure for existing concrete beams according to any one of claims 1 to 4, characterized in that: The prefabricated concrete skin reinforcement structure adopts a modular design and can be adjusted according to concrete beams of different cross-sectional sizes, thereby improving the flexibility and adaptability of the reinforcement structure.

6. A construction method for a modular reinforcement structure of an existing concrete beam, characterized in that: The following steps are involved: Prefabricated component production: Prefabricated concrete skin reinforcement structures are produced in the prefabricated component production plant in accordance with the design documents and relevant specifications. The concrete strength grade of the prefabricated concrete skin reinforcement structure is not less than C30, the thickness is not less than 60mm, and longitudinal reinforcement is provided at the top and bottom, waist reinforcement is provided in the middle, and open stirrups are provided on the outside; Site preparation: remove the surface concrete of the original concrete beam until the stirrups and longitudinal reinforcement are exposed, and clean the surface of the concrete beam and perform rust removal; Install prefabricated components: Install the prefabricated concrete outer skin reinforcement structure on the outside of the original beam body, ensuring that there is a gap between the upper surface of the outer skin structure and the floor slab, and that the distance between the inner surface of the outer skin reinforcement structure and the outer surface of the original beam body is not less than 70mm. At the same time, set supports and adjustable top supports at the bottom of the outer skin reinforcement structure; Anchoring measures: Anchor the upper and lower longitudinal reinforcements of the precast concrete skin reinforcement structure into the structural columns on both sides of the beam; Pouring high-strength fine stone concrete: Pouring high-strength fine stone concrete in the gap and the cavity between the outer skin reinforcement structure and the original beam body. The strength grade of the high-strength fine stone concrete is higher than that of the newly added concrete outer skin structure and the original beam body; Curing and demoulding: Carry out curing of high-strength fine stone concrete. After the strength grade of fine stone concrete reaches 100% of the design strength, remove the supports and adjustable supports of the outer skin reinforcement structure.

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