Prefabricated concrete laminated slab

Abstract

The utility model discloses a prefabricated concrete laminated slab which comprises a prefabricated concrete bottom slab and a plurality of plane steel bar trusses arranged on the prefabricated concrete bottom slab at intervals in the width direction of the prefabricated concrete bottom slab, and the lower ends of the plane steel bar trusses are embedded in the prefabricated concrete bottom slab. The lower ends of the multiple plane steel bar trusses are connected and fixed through bottom plate transverse steel bars pre-buried in the prefabricated concrete bottom plate, and a plurality of notches are formed in the side edges of the two ends of the prefabricated concrete bottom plate in the width direction. The multiple notches are evenly distributed in the length direction of the prefabricated concrete bottom plates in a spaced mode and used for placing lap joint steel bars when the side edges of the adjacent prefabricated concrete bottom plates are spliced, and a whole is formed after concrete is cast in place. The notches used for splicing are formed in the two side edges of the prefabricated concrete bottom plates in the width direction, so that post-cast strips do not need to be arranged at the splicing seams of the adjacent prefabricated concrete bottom plates, the lap joint steel bars are directly placed in the notches, and then concrete is cast in place to form a whole.

Description

Technical Field

[0001] This utility model relates to the field of prefabricated building floor slab technology, specifically to a precast concrete composite slab. Background Technology

[0002] Composite slabs are assembled monolithic floor slabs made by stacking precast slabs and cast-in-place concrete layers. Composite slabs have good integrity, and the upper and lower surfaces of the slabs are flat, which facilitates the finishing layer decoration. They are suitable for high-rise buildings and large-span buildings with high requirements for overall rigidity.

[0003] Existing precast concrete slabs typically use triangular steel trusses for their reinforcing bars. However, due to the large spacing between adjacent triangular trusses, the low degree of prefabrication, and the lack of connecting structures between adjacent triangular trusses, cracking occurs during the hoisting and installation of the precast concrete composite slab. Furthermore, existing methods for splicing precast concrete slabs generally involve setting up a post-cast strip at the joint and then casting concrete in place at the joint to form a connection. This undoubtedly adds the construction steps of the post-cast strip and its formwork to the overall construction process. Alternatively, adjacent precast concrete slabs can be directly spliced ​​together, with lapped reinforcing bars placed on the upper surface of the adjacent slabs and concrete poured in place to form a whole. However, this method adds an extra layer of cast-in-place concrete to the upper surface of the precast concrete slab, which can easily result in a larger overall thickness of the final precast concrete composite slab, making it difficult to meet design requirements.

[0004] Therefore, to solve the above problems, it is necessary to improve the existing precast concrete composite slab structure. Utility Model Content

[0005] In view of this, the precast concrete composite slab provided by this utility model uses a planar steel truss instead of a traditional triangular steel truss in the precast concrete base slab, so that the steel truss arrangement is more compact. At the same time, transverse steel bars are set between the planar steel trusses as out-of-plane supports for the upper chord steel bars of the planar trusses, so that the upper chord steel bars of the planar trusses are connected to form a whole, thereby improving the overall load-bearing performance of the precast base slab and avoiding cracking problems in the precast concrete composite slab base slab during hoisting and construction installation. In addition, grooves are set on both sides of the width of the precast concrete base slab for splicing, so that there is no need to set a post-pouring strip at the joint between adjacent precast concrete base slabs. The lapped steel bars are placed directly in the groove and then the concrete is poured in place to form a whole.

[0006] This utility model provides a precast concrete composite slab, comprising a precast concrete base slab and a plurality of planar steel trusses spaced apart on the precast concrete base slab along its width direction. The lower ends of the planar steel trusses are embedded in the precast concrete base slab. The lower ends of the plurality of planar steel trusses are connected and fixed by transverse steel bars embedded in the base slab. The two ends of the width of the precast concrete base slab are provided with a plurality of slots. The plurality of slots are evenly distributed along the length direction of the precast concrete base slab and are used to place lapped steel bars when splicing the side joints of adjacent precast concrete base slabs, and then form a whole after the concrete is poured in place.

[0007] Furthermore, the slot position is set corresponding to the position of the transverse reinforcement of the bottom plate and is located on the same horizontal straight line.

[0008] Furthermore, the upper ends of several planar steel trusses are connected to form a whole by transverse steel bars arranged perpendicular to the length direction of the precast concrete base plate, and the transverse steel bars are composed of several transverse steel bars arranged at even intervals.

[0009] Furthermore, the planar steel truss includes a lower chord steel bar embedded in the precast concrete base slab, an upper chord steel bar disposed above the precast concrete base slab, and web steel bars for connecting the lower chord steel bar and the upper chord steel bar, wherein the lower chord steel bar, the upper chord steel bar, and the web steel bars are located on the same vertical plane.

[0010] Furthermore, the transverse reinforcing bars are perpendicularly orthogonally arranged above or below the upper chord reinforcing bars, and the transverse reinforcing bars of the bottom plate are perpendicularly orthogonal to the length direction of the lower chord reinforcing bars and are arranged above or below the lower chord reinforcing bars.

[0011] Furthermore, the web reinforcement bars are arranged in a wavy pattern between the upper chord reinforcement bars and the lower chord reinforcement bars.

[0012] The beneficial effects of this utility model are as follows: The precast concrete composite slab of this utility model has high rigidity, good quality, high efficiency, and low cost. It effectively avoids the problem of cracking of the concrete composite slab base plate during hoisting and construction installation. Moreover, the longitudinal steel bars of the planar steel truss can be fully utilized in all stages of production, hoisting, construction installation, and use. The slots set on both sides of the width of the precast concrete base plate for splicing eliminate the need to set post-pouring strips at the joints between adjacent precast concrete base plates. The lapped steel bars can be placed directly in the slots and then the concrete can be poured in place to form a whole, which effectively improves the construction efficiency. Attached Figure Description

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0014] Figure 1This is a schematic diagram of the structure of the precast concrete composite slab in this utility model;

[0015] Figure 2 for Figure 1 AA section view in the middle;

[0016] Figure 3 for Figure 1 BB section view in the middle;

[0017] In the diagram: 1-Planar steel truss; 2-Transverse reinforcement; 3-Precast concrete base slab; 4-Lower chord reinforcement; 5-Upper chord reinforcement; 6-Web reinforcement; 7-Transverse reinforcement of base slab; 8-Groove. Detailed Implementation

[0018] As shown in the figure, the present invention provides a precast concrete composite slab, comprising a precast concrete base slab 3 and a plurality of planar steel trusses 1 spaced apart along the width direction of the precast concrete base slab 3. The lower ends of the planar steel trusses 1 are embedded in the precast concrete base slab 3. The lower ends of the plurality of planar steel trusses 1 are connected and fixed by transverse steel bars 7 embedded in the precast concrete base slab 3. The two sides of the width of the precast concrete base slab 3 are provided with a plurality of slots 8. The plurality of slots 8 are evenly distributed along the length direction of the precast concrete base slab 3 and are used to place lapped steel bars when splicing the sides of adjacent precast concrete base slabs 3 and to form a whole after the concrete is poured in place.

[0019] In the design of this precast concrete composite slab, the thickness, width, and length of the precast concrete base slab 3, the spacing between the planar steel trusses 1, the spacing between the transverse steel bars 7 and 2, and the specific steel bar diameters are determined according to design requirements. By using planar steel trusses 1 instead of traditional triangular steel trusses, the planar steel trusses 1 are arranged more closely, resulting in greater rigidity, better quality, higher efficiency, and lower cost for the precast concrete composite slab, enabling construction with no or less support and formwork at mid-span. At the same time, the transverse steel bars 2 between the planar steel trusses 1 effectively prevent cracking of the concrete composite slab base slab during hoisting and installation, and the longitudinal steel bars of the planar steel trusses 1 can be fully utilized in all stages of production, hoisting, installation, and use. The slots 8 set on both sides of the width of the precast concrete base slab 3 eliminate the need for post-pouring strips at the joints between adjacent precast concrete base slabs 3. The lapped steel bars can be placed directly in the slots 8 and then the concrete can be poured in place to form a whole, which effectively improves construction efficiency and allows the precast concrete base slab 3 to be used as a two-way slab. At the same time, the groove shape, groove depth, length and spacing of the slots 8 are determined according to the design requirements.

[0020] In this embodiment, the slot 8 is positioned corresponding to the position of the transverse reinforcement 7 of the base plate and is located on the same horizontal line. Since the transverse reinforcement 7 of the base plate is only used to connect the lower chord reinforcement 4 of the planar steel truss 1, and after the slot 8 is opened on the side of the precast concrete base plate 3, lap reinforcement will be placed when splicing with the adjacent precast concrete base plate 3 to achieve continuous stress at the joint of the precast concrete base plate 3, in order to ensure the local connection strength at the slot 8, the position of the slot 8 needs to be positioned corresponding to the position of the transverse reinforcement 7 of the base plate and located on the same horizontal line, so that the precast concrete base plate 3 can be used as a two-way slab.

[0021] In this embodiment, the upper ends of several planar steel trusses 1 are connected to form a whole by transverse steel reinforcement groups arranged perpendicularly and orthogonally to the length direction of the precast concrete base slab 3. The transverse steel reinforcement groups are composed of several transverse steel reinforcements 2 arranged at uniform intervals. The planar steel truss 1 includes a lower chord steel reinforcement 4 embedded in the precast concrete base slab 3, an upper chord steel reinforcement 5 arranged above the precast concrete base slab 3, and a web steel reinforcement 6 for connecting the lower chord steel reinforcement 4 and the upper chord steel reinforcement 5. The lower chord steel reinforcement 4, the upper chord steel reinforcement 5, and the web steel reinforcement 6 are located on the same vertical plane. The transverse steel reinforcement 2 is arranged perpendicularly and orthogonally above or below the upper chord steel reinforcement 5. The base slab transverse steel reinforcement 7 is arranged perpendicularly and orthogonally to the length direction of the lower chord steel reinforcement 4 above or below the lower chord steel reinforcement 4. The base slab transverse steel reinforcement 7 is tightly attached to the lower chord steel reinforcement 4 and then fixed by binding or welding. The web steel reinforcement 6 is arranged in a wavy shape between the upper chord steel reinforcement 5 and the lower chord steel reinforcement 4.

[0022] Combination Figures 1 to 3 As shown, the planar steel truss 1 is composed of a lower chord steel bar 4, an upper chord steel bar 5, and a web steel bar 6 located in the same vertical plane. By arranging the web steel bar 6 in a wavy shape between the upper chord steel bar 5 and the lower chord steel bar 4, the connection strength between the upper chord steel bar 5 and the lower chord steel bar 4 is ensured, while the overall strength of the planar steel truss 1 is strengthened. Compared with the traditional triangular steel truss precast concrete composite slab, the precast concrete composite slab with the planar steel truss has a smaller spacing between adjacent trusses and a denser truss arrangement, which can reduce the arrangement of formwork and supports when using the precast concrete composite slab.

[0023] In one embodiment, the lower chord reinforcement 4 of the planar steel truss 1 needs to be exposed, while the transverse reinforcement 7 of the precast concrete base slab 3 does not need to be exposed. In another embodiment, several slots 8 are set on the sides of both ends of the length of the precast concrete base slab 3, and the several slots 8 are evenly distributed along the width direction of the precast concrete base slab 3 and are used to place lap reinforcement when splicing the sides of adjacent precast concrete base slabs 3 and to form a whole after the concrete is poured in place. In yet another embodiment, several slots 8 are provided at both ends of the length and width directions of the precast concrete base slab 3 to achieve the four-sided lap splicing treatment of the horizontal plane.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A precast concrete composite slab, characterized in that: The system includes a precast concrete base slab and several planar steel trusses spaced apart along the width of the precast concrete base slab. The lower ends of the planar steel trusses are embedded in the precast concrete base slab. The lower ends of the planar steel trusses are connected and fixed by transverse steel bars embedded in the base slab. Several slots are provided on both sides of the width of the precast concrete base slab. The slots are evenly distributed along the length of the precast concrete base slab and are used to place lapped steel bars when splicing the sides of adjacent precast concrete base slabs, and then form a whole after the concrete is poured in place.

2. The precast concrete composite slab according to claim 1, characterized in that: The slot is positioned corresponding to the position of the transverse reinforcing bars in the base plate and is located on the same horizontal straight line.

3. The precast concrete composite slab according to claim 2, characterized in that: The upper ends of several planar steel trusses are connected to form a whole by transverse steel bars arranged perpendicular to the length direction of the precast concrete base plate. The transverse steel bars are composed of several transverse steel bars arranged at even intervals.

4. The precast concrete composite slab according to claim 2, characterized in that: The planar steel truss includes a lower chord steel bar embedded in the precast concrete base slab, an upper chord steel bar disposed above the precast concrete base slab, and web steel bars for connecting the lower chord steel bar and the upper chord steel bar, wherein the lower chord steel bar, the upper chord steel bar, and the web steel bars are located on the same vertical plane.

5. The precast concrete composite slab according to claim 4, characterized in that: The transverse reinforcing bars are perpendicularly or orthogonally arranged above or below the upper chord reinforcing bars, and the transverse reinforcing bars of the bottom plate are perpendicularly or orthogonally arranged above or below the lower chord reinforcing bars in the length direction of the lower chord reinforcing bars.

6. The precast concrete composite slab according to claim 4, characterized in that: The web reinforcement bars are arranged in a wavy pattern between the upper chord reinforcement bars and the lower chord reinforcement bars.

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