Prestressed concrete composite beam

Abstract

The utility model provides a kind of prestressed concrete composite beam, in the length direction of the prestressed concrete composite beam, the prestressed concrete composite beam is divided into middle prefabricated composite beam section and end prefabricated composite beam section, the end prefabricated composite beam section is set to the both sides of the middle prefabricated composite beam section, wherein the middle prefabricated composite beam section is set to be suitable for stretching into support.This prestressed concrete composite beam, prestressed reinforcement is arranged at the bottom, so that the overall rigidity of the beam is strengthened, the main beam can be supported by few supports, the secondary beam and the plate can be supported without supports, and only the prestressed reinforcement is stretched out, avoiding the problem of collision between the reinforcement of the prefabricated beam and the reinforcement of the column and beam during installation, and being easy to install;The middle prefabricated composite beam section adopts a rectangular composite section, and the end prefabricated composite beam section is a U-shaped section, which reduces the amount of site-poured concrete, reduces the self-weight of the prefabricated component, and reduces the difficulty of transportation and on-site lifting and installation.

Description

Technical Field

[0001] This utility model relates to the field of composite beam technology, and in particular to a prestressed concrete composite beam. Background Technology

[0002] Precast composite beams are generally made of ordinary reinforced concrete, prestressed reinforced concrete, or prestressed reinforced concrete steel truss composite beams.

[0003] However, the existing composite beams mentioned above have the following drawbacks:

[0004] Due to their heavy weight, ordinary reinforced concrete precast composite beams and prestressed reinforced concrete precast composite beams are prone to steel bar collisions, making it difficult to guarantee the quality of on-site installation.

[0005] Prestressed reinforced concrete composite beams with steel pipe trusses have no side plates, resulting in a large workload for on-site construction, including formwork, beam and slab support, rebar tying, and concrete pouring, making it difficult to achieve the original intention of convenient and quick prefabricated concrete structures.

[0006] Therefore, in order to solve the above problems, this utility model proposes a prestressed concrete composite beam that can avoid steel bar collision, reduce self-weight and reduce on-site workload. Utility Model Content

[0007] To address the problems of existing composite beams where reinforcing bars are prone to collisions affecting installation quality, precast components are heavy, and on-site construction workload is large, this utility model provides a prestressed concrete composite beam.

[0008] According to one objective of this utility model, this utility model provides a prestressed concrete composite beam, wherein the prestressed concrete composite beam is divided into a middle precast composite beam segment and an end precast composite beam segment along its length, and the end precast composite beam segments are disposed on both sides of the middle precast composite beam segment. The prestressed concrete composite beam includes:

[0009] The base plate and the reinforcing cage hidden inside the base plate, wherein the bottom of the reinforcing cage is provided with prestressed reinforcing bars, and the ends of the prestressed reinforcing bars extend to the outside of the base plate along the length of the prestressed concrete composite beam.

[0010] In the middle precast composite beam segment, the bottom plate has a rectangular cross-section, and the reinforcing cage is embedded in the inner side of the bottom plate. In the end precast composite beam segment, the bottom plate has a U-shaped cross-section, and the reinforcing cage is anchored into the inner side of the bottom plate.

[0011] The reinforcing cage includes a lower longitudinal bar 1. The lower longitudinal bar 1 is continuously arranged in the middle precast composite beam segment and the end precast composite beam segment. In the middle precast composite beam segment, the reinforcing cage also includes a lower longitudinal bar 2. The lower longitudinal bar 2 is arranged to extend into the support. The lower longitudinal bar 2 is provided with a detachable connection at the end of the middle precast composite beam segment.

[0012] Preferably, in the vertical direction, the steel cage includes the lower longitudinal bars one and the lower longitudinal bars two located at the bottom, the waist bars and tie bars located in the middle, and the stirrups located at the top;

[0013] The bottom longitudinal reinforcement and the bottom plate of the precast composite beam segment at the end are connected by a connector.

[0014] Preferably, the connector is located at the end of the rectangular cross-section of the bottom plate of the precast composite beam segment.

[0015] Preferably, the web reinforcement of the end precast composite beam segment and the web reinforcement of the middle precast composite beam segment are continuously provided.

[0016] Preferably, the stirrups are U-shaped open stirrups, the stirrups are arranged at relative intervals, and the stirrups are connected by horizontal sections to form a closed stirrup.

[0017] Preferably, a shear keyway is provided between the bottom plate end face of the middle precast composite beam segment and the bottom plate end face of the end precast composite beam segment.

[0018] Preferably, the top of the middle precast composite beam segment and the side of the end precast composite beam segment are configured to connect precast composite slabs.

[0019] Compared with the prior art, the beneficial effects of this utility model are:

[0020] This prestressed concrete composite beam has prestressed steel bars at the bottom, which enhances the overall stiffness of the beam. It can achieve less support for the main beam and no support for the secondary beams and slabs. Moreover, only the prestressed steel bars protrude, avoiding the problem of collision between the precast beam steel bars and the column and beam steel bars during installation, and is easy to install.

[0021] The central precast composite beam segment adopts a rectangular composite section, while the end precast composite beam segment has a U-shaped section, which reduces the amount of concrete poured on site, while also reducing the self-weight of the precast components and reducing the difficulty of transportation and on-site lifting and installation.

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] Figure 1 This is a front view schematic diagram of a prestressed concrete composite beam according to the present invention;

[0024] Figure 2 This is a front view schematic diagram of the reinforcement of a prestressed concrete composite beam according to the present invention;

[0025] Figure 3 for Figure 2 Schematic diagram of BB in the middle;

[0026] Figure 4 for Figure 2 Schematic diagram of CC in the middle;

[0027] Figure 5 for Figure 2 Schematic diagram of EE in China;

[0028] Figure 6 for Figure 2 Schematic diagram of FF in China. Detailed Implementation

[0029] The following description is intended to provide a detailed account of the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the present invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0030] Please see Figure 1-6 This utility model provides a technical solution: a prestressed concrete composite beam, wherein the prestressed concrete composite beam is divided into a middle precast composite beam segment 100 and an end precast composite beam segment 200 along its length, and the end precast composite beam segments 200 are disposed on both sides of the middle precast composite beam segment 100. The prestressed concrete composite beam includes:

[0031] The base plate 300 and the reinforcing cage 400 hidden inside the base plate 300 are provided with prestressed steel bars 500 at the bottom of the reinforcing cage 400. In the length direction of the prestressed concrete composite beam, the end of the prestressed steel bar 500 extends to the outside of the base plate 300.

[0032] In the middle precast composite beam segment 100, the base plate 300 has a rectangular cross-section, and the reinforcing cage 400 is embedded in the inner side of the base plate 300. In the end precast composite beam segment 200, the base plate 300 has a U-shaped cross-section, and the reinforcing cage 400 is anchored in the inner side of the base plate 300. The reinforcing cage 400 includes a lower longitudinal reinforcement 405. The lower longitudinal reinforcement 405 in the middle precast composite beam segment 100 and the end precast composite beam segment 200 are continuously arranged. In the middle precast composite beam segment 100, the reinforcing cage 400 also includes a lower longitudinal reinforcement 401. The lower longitudinal reinforcement 401 is configured to extend into the support. The lower longitudinal reinforcement 401 is provided with a detachable connection at the end of the middle precast composite beam segment 100.

[0033] This prestressed concrete composite beam has 500 prestressed steel bars at the bottom, which enhances the overall stiffness of the beam. It can achieve less support for the main beam and no support for the secondary beams and slabs. Moreover, only the 500 prestressed steel bars protrude, avoiding the problem of collision between the precast beam steel bars and the column and beam steel bars during installation, and is easy to install.

[0034] The middle precast composite beam segment 100 adopts a rectangular composite section, while the end precast composite beam segment 200 has a U-shaped section, reducing the amount of concrete poured on site and also reducing the self-weight of the precast components, thus reducing the difficulty of transportation and on-site lifting and installation. The self-weight of this prestressed concrete composite beam is 60% to 70% of that of a conventional precast beam. In addition, the steel cage 400 of the end precast composite beam segment 200 is precast in the bottom plate 300 of its U-shaped section, which does not affect on-site installation. The steel cage 400 of the middle precast composite beam segment 100 is placed on the bottom plate 300 of the rectangular section. The steel cage 400 of the end precast composite beam segment 200 and the steel cage 400 of the end precast composite beam segment 200 are detachably connected, and the steel bars are extended on site into the support, with the reserved length facilitating the adjustment of the steel bar position on site.

[0035] Specifically, in the vertical direction, the steel cage 400 includes the lower longitudinal reinforcement 405 and the lower longitudinal reinforcement 401 located at the bottom, the waist reinforcement 402 and the tie reinforcement 403 located in the middle, and the stirrups 404 located at the top.

[0036] The lower longitudinal reinforcement 405 is positioned close to the bottom of the U-shaped section of the precast composite beam segment 200 at the end. The lower longitudinal reinforcement 401 is positioned above the lower longitudinal reinforcement 405. In the horizontal direction, there are two lower longitudinal reinforcements 401 and two lower longitudinal reinforcements 405. The lower longitudinal reinforcement 405 corresponds to the two corners of the precast composite beam segment 200 at the end. The lower longitudinal reinforcement 401 is positioned on the inner side opposite to the lower longitudinal reinforcement 405, so as to improve the stability of the connection between the two composite beam segments.

[0037] The lower longitudinal reinforcement 401 and the bottom plate 300 of the precast composite beam segment 200 are connected by a connector 600, wherein the connector 600 is located at the end of the rectangular section of the bottom plate 300 of the precast composite beam segment 200. The on-site extension of the reinforcing bars extends into the support, and the reserved length is conducive to the on-site adjustment of the reinforcing bar position.

[0038] The web reinforcement 402 of the end precast composite beam segment 200 and the web reinforcement 402 of the middle precast composite beam segment 100 are continuously provided.

[0039] The stirrup 404 is a U-shaped open stirrup 404. The stirrups 404 are arranged at relative intervals and are connected by horizontal sections to form a closed stirrup.

[0040] During installation, the prestressed concrete composite beam contains the following reinforcements: bottom prestressed reinforcement 500, lower longitudinal reinforcement 1 of the steel cage 400 in the middle prestressed composite beam segment 100, and lower longitudinal reinforcement 1 of the steel cage 400 in the end prestressed composite beam segment 200. The lower longitudinal reinforcement 1 is ordinary steel reinforcement, and includes web reinforcement 402, tie reinforcement 403, and U-shaped open stirrups 404. The reinforcements installed later include: upper beam reinforcement, lower longitudinal reinforcement 2 401 connected to the bottom plate 300 of the end prestressed composite beam segment 200 by a connector, horizontal stirrup segment connected to the open stirrups 404 to form a closed stirrup, and web reinforcement 402 of the end prestressed composite beam segment 200 lapped with the embedded web reinforcement 402 of the middle prestressed composite beam segment 100. On-site reinforcement tying mainly involves the upper beam reinforcement and the top stirrups 404, resulting in a small amount of on-site reinforcement work.

[0041] To address the issues of weak shear capacity and excessive additional reinforcement at the vertical joints of existing composite beams, which increases installation difficulty, a shear-resistant keyway 301 is further provided between the end face of the bottom plate 300 of the middle precast composite beam segment 100 and the end face of the bottom plate 300 of the end precast composite beam segment 200. This strengthens the shear capacity of the vertical joints at the beam ends, transferring the weak points of the cast-in-place and precast vertical joints to the beam span 1 / 3 region with lower shear force, making it easier to meet stress requirements and satisfy shear resistance needs.

[0042] Furthermore, the top of the middle precast composite beam segment 100 and the sides of the end precast composite beam segment 200 are configured to connect to the precast composite slab, thereby achieving the effect of eliminating the need for side formwork and reducing the amount of on-site formwork work. The bottom plate 300 of the end precast composite beam segment 200 includes a side plate portion and a bottom plate portion. The side plate portions are disposed on opposite sides of the bottom plate portion to form a U-shaped cross-section. The side plate portions are configured to connect with the precast composite slab.

[0043] The prestressed concrete composite beam also includes: a hanging nail 700, which is disposed on the bottom plate 300 of the middle precast composite beam segment 100.

[0044] This prestressed concrete composite beam, with a rectangular cross-section, has a central precast composite beam segment 100 and two U-shaped end precast composite beam segments 200. It is suitable for precast beams of different spans, with a beam cross-section width ≥300 and a height ≥400.

[0045] In summary, this prestressed concrete composite beam can improve the efficiency of on-site construction, make the construction of prefabricated concrete structures more convenient, accelerate the construction progress, and ensure construction safety. At the same time, because issues such as steel bar collision and joint connection strength are resolved, the construction quality is guaranteed and it is easy to meet quality and safety requirements.

[0046] The embodiments described above are only used to illustrate the technical ideas and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly. The scope of patent application of this utility model should not be limited by these embodiments. That is, any equivalent changes or modifications made in accordance with the spirit disclosed in this utility model still fall within the patent scope of this utility model.

Claims

1. A prestressed concrete composite beam, characterized in that, Along the length of the prestressed concrete composite beam, the prestressed concrete composite beam is divided into a middle precast composite beam segment (100) and an end precast composite beam segment (200). The end precast composite beam segments (200) are disposed on both sides of the middle precast composite beam segment (100). The prestressed concrete composite beam includes: The base plate (300) and the reinforcing cage (400) hidden inside the base plate (300) are provided with prestressed steel bars (500) at the bottom of the reinforcing cage (400). In the length direction of the prestressed concrete composite beam, the ends of the prestressed steel bars (500) extend to the outside of the base plate (300). In the middle precast composite beam segment (100), the bottom plate (300) has a rectangular cross section, and the reinforcing cage (400) is embedded in the inner side of the bottom plate (300). In the end precast composite beam segment (200), the bottom plate (300) has a U-shaped cross section, and the reinforcing cage (400) is anchored into the inner side of the bottom plate (300). The steel cage (400) includes a lower longitudinal bar (405), which is continuously arranged in the middle precast composite beam segment (100) and the end precast composite beam segment (200). In the middle precast composite beam segment (100), the steel cage (400) also includes a lower longitudinal bar (401), which is adapted to extend into the support. The lower longitudinal bar (401) is provided with a detachable connection at the end of the middle precast composite beam segment (100).

2. The prestressed concrete composite beam according to claim 1, characterized in that, In the vertical direction, the steel cage (400) includes the lower longitudinal reinforcement one (405) and the lower longitudinal reinforcement two (401) located at the bottom, the waist reinforcement (402) and the tie reinforcement (403) located in the middle, and the stirrups (404) located at the top. The bottom longitudinal reinforcement 2 (401) and the bottom plate (300) of the precast composite beam segment (200) at the end are connected by a connector (600).

3. A prestressed concrete composite beam according to claim 2, characterized in that, The connector (600) is located at the end of the rectangular section of the bottom plate (300) of the precast composite beam segment (200).

4. A prestressed concrete composite beam according to claim 2, characterized in that, The web reinforcement (402) of the end precast composite beam segment (200) and the web reinforcement (402) of the middle precast composite beam segment (100) are continuously provided.

5. A prestressed concrete composite beam according to claim 2, characterized in that, The stirrups (404) are U-shaped open stirrups (404), and the stirrups (404) are arranged at relative intervals. The stirrups (404) are connected by horizontal sections to form a closed stirrup.

6. A prestressed concrete composite beam according to claim 1, characterized in that, A shear keyway (301) is provided between the end face of the bottom plate (300) of the middle precast composite beam segment (100) and the end face of the bottom plate (300) of the end precast composite beam segment (200).

7. A prestressed concrete composite beam according to claim 1, characterized in that, The top of the middle precast composite beam segment (100) and the sides of the end precast composite beam segment (200) are provided to be adapted to connect the precast composite slab.

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