Prestressed concrete plane steel bar truss laminated slab

Abstract

The invention relates to a prestressed concrete plane steel bar truss laminated slab, which is characterized in that web member steel bars which are continuously bent to form a wave shape are connected with upper chord steel bars to form a plane truss, the lower parts of the web member steel bars are embedded in a concrete bottom plate, and prestressed longitudinal bars are arranged in the concrete bottom plate in the direction parallel to the upper chord steel bars; supporting steel bars are arranged on the upper portion of the plane truss, the supporting steel bars are bent at intervals to form triangular supporting sections, the triangular supporting sections are pressed on the upper chord steel bars, the triangular supporting sections and the upper chord steel bars are fixed, the horizontal connecting sections connected with the triangular supporting sections are embedded into the concrete bottom plate, and the prestressed longitudinal bars are fixedly connected with the horizontal connecting sections. The method has the advantages that construction is convenient and fast, the steel consumption is small, and out-of-plane instability of the plane truss is avoided.

Description

Technical Field

[0001] The invention relates to the field of prefabricated buildings, and in particular to a prestressed concrete flat steel bar truss composite slab. Background Art

[0002] Concrete truss composite slabs are widely used in the construction industry. This type of product can reduce the wet work steps and the use of construction formwork and scaffolding during the construction process, reduce labor consumption, reduce construction difficulty, and improve construction efficiency.

[0003] The invention patent with announcement number CN105756252B9 discloses "a prestressed concrete truss composite plate and its manufacturing method". The upper chord of the truss in the patent is made of steel pipes filled with concrete, and a row of webs are arranged on both sides of the upper chord, and transverse steel bars are also arranged in the bottom plate. This structural design makes the overall weight of the truss heavier, the amount of steel required is larger, and the processing process is very cumbersome.

[0004] The utility model patent with announcement number CN211817290U discloses "a prestressed plane truss reinforced concrete composite slab bottom plate". In this patent, a plane truss is used instead of a steel tube truss. The plane truss is composed of upper chord steel bars, web bars and lower chord steel bars, and transverse steel bars are also provided in the bottom plate. Although the solution given in this patent helps to reduce the overall weight of the truss, the amount of steel used in this solution will also increase because the plane truss used is provided with a lower chord steel bar and transverse steel bars are provided in the bottom plate. Furthermore, the plane truss used in this patent lacks effective support on the side, making it difficult to achieve the stability of the truss. Summary of the invention

[0005] The invention discloses a prestressed concrete plane steel bar truss composite plate, which eliminates the lower chord steel bars in the plane truss, reduces the steel consumption, adds side supports to the plane truss, and improves the stability of the plane truss.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A prestressed concrete plane steel bar truss composite plate comprises a concrete bottom plate, a plane truss, prestressed longitudinal bars and supporting bars. The plane truss is composed of upper chord bars and web bars. The web bars are bent to form a continuous wave shape. The wave crests of the web bars are welded to the bottom of the upper chord bars. The supporting bars comprise triangular supporting segments arranged at intervals and horizontal connecting segments connecting adjacent triangular supporting segments. The triangular supporting segments are formed by bending the supporting bars, and the bottoms of the triangular supporting segments are open. The plane trusses are arranged at intervals on the concrete bottom plate. The wave troughs of the web bars are embedded in the concrete bottom plate. Prestressed longitudinal bars are arranged at intervals in the concrete bottom plate. The length direction of the prestressed longitudinal bars is parallel to the length direction of the upper chord bars. Support bars are arranged at intervals on the upper part of the plane truss. The length direction of the support bars is perpendicular to the length direction of the upper chord bars. The triangular supporting segments of the support bars are pressed on the upper chord bars of the plane truss. The triangular supporting segments are fixedly connected to the upper chord bars. The horizontal connecting segments of the support bars are embedded in the concrete bottom plate. The prestressed longitudinal bars are fixedly connected to the horizontal connecting segments.

[0007] Furthermore, the thickness of the concrete base plate is not less than 35 mm.

[0008] Furthermore, the diameter of the upper chord steel bar is 12 mm to 16 mm.

[0009] The plane truss designed by the present invention eliminates the lower chord steel bars and adopts a single row of web bars that are continuously bent to be connected to the upper chord steel bars, which reduces the construction complexity caused by the lateral arrangement, simplifies the manufacturing steps of the plane truss, and saves steel. The upper chord bars in the plane truss are changed from traditional steel pipes to upper chord steel bars, which can reduce the overall weight of the truss and reduce the manufacturing cost of the truss by 20%. The present invention improves the structure of the traditional transverse steel bars set in the concrete base plate, forms triangular support sections by bending at intervals, and utilizes the triangular support sections to support the plane truss out of the plane to avoid out-of-plane instability. The horizontal connection section of the support steel bar is buried in the concrete base plate to provide bearing capacity in the transverse direction during the construction phase to prevent cracking of the concrete bottom. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of a prestressed concrete plane truss composite slab in an embodiment; Figure 2 for Figure 1 Exploded diagram of Figure 3 It is a structural diagram of a plane truss; Figure 4 It is a schematic diagram of the structure of the supporting steel bars; Figure 5 for Figure 1 A top view of Figure 6 for Figure 5Middle AA section; Figure 7 for Figure 5 Middle BB cross-section.

[0011] Reference numerals: 1. Upper chord reinforcement; 2. Web reinforcement; 3. Support reinforcement; 31. Triangular support section; 32. Horizontal connection section; 4. Plane truss; 5. Concrete base plate; 6. Prestressed longitudinal reinforcement. DETAILED DESCRIPTION

[0012] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0013] This embodiment discloses a prestressed concrete flat steel bar truss composite plate, such as Figure 1 and Figure 2 As shown in FIG. 1 , it mainly includes a concrete base plate 5, a plane truss 4, prestressed longitudinal bars 6 and supporting steel bars 3. Among them, the structure of the plane truss 4 is as follows Figure 3 As shown, it is composed of an upper chord steel bar 1 and a web steel bar 2. The upper chord steel bar 1 is made of steel bars with a diameter of 12 mm to 16 mm. The web steel bar 2 is formed into a continuous wave-shaped structure by continuously bending straight steel bars. The web steel bar 2 serves as the lateral support of the plane truss. Each wave crest of the bent web steel bar 2 is welded to the bottom of the upper chord steel bar 1, thereby forming a plane truss 4. In this embodiment, the transverse steel bar in the prior art is structurally improved and used as the support steel bar 3 in this embodiment. The structure of the support steel bar 3 is as shown in FIG. Figure 4 As shown, the supporting steel bars 3 are formed into a plurality of spaced-apart triangular supporting segments 31 by bending straight steel bars upward at intervals, wherein the lower portion of the triangular supporting segment 31 is an open end, and the portion that is not bent and connects adjacent triangular supporting segments 31 is called a horizontal connecting segment 32.

[0014] The assembly relationship of the above-mentioned components is as follows: Figure 1 , Figures 5 to 7 As shown, prestressed longitudinal bars 6 are arranged at equal intervals inside the concrete base plate 5, and the prestressed longitudinal bars 6 can improve the rigidity and strength of the concrete base plate 5; a plurality of plane trusses 4 are arranged at equal intervals on the upper part of the concrete base plate 5, and the length direction of the upper chord steel bars 1 of the plane truss 4 is arranged in parallel with the length direction of the prestressed longitudinal bars 6, so that each trough of the web steel bars 2 is buried in the interior of the concrete base plate 5; a plurality of supporting steel bars 3 are arranged at equal intervals on the upper part of the plane truss 4, and the length direction of the supporting steel bars 3 is perpendicular to the length direction of the upper chord steel bars 1, so that the triangular supporting section 31 of each supporting steel bar 3 is just pressed on the upper chord steel bar 1 of the plane truss 4, the triangular supporting section 31 is fixedly connected to the upper chord steel bar 1, the horizontal connecting section 32 of the supporting steel bar 3 is embedded in the concrete base plate 5, and the prestressed longitudinal bars 6 are fixedly connected to the horizontal connecting section 32.

[0015] The present invention uses prestressed technology, bending and pre-embedding of steel bars to form a prestressed concrete flat truss composite slab with compact structure, high rigidity and high strength. The thickness of the concrete bottom plate 5 is not less than 35 mm, which meets the requirements for the rigidity of the composite slab during construction, helps to reduce the wet operation steps in the construction process, reduces the construction difficulty, improves the construction efficiency, and reduces the overall structural deadweight of the building.

[0016] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A prestressed concrete flat steel bar truss composite slab, characterized in that: It includes a concrete base plate, a plane truss, prestressed longitudinal bars and supporting steel bars. The plane truss is composed of upper chord steel bars and web steel bars. The web steel bars are bent to form a continuous wave shape. The wave crests of the web steel bars are welded to the bottom of the upper chord steel bars. The supporting steel bars include triangular supporting segments arranged at intervals and horizontal connecting segments connecting adjacent triangular supporting segments. The triangular supporting segments are formed by bending the supporting steel bars, and the bottoms of the triangular supporting segments are open. The plane trusses are arranged at intervals on the concrete base plate, the wave troughs of the web steel bars are embedded in the concrete base plate, prestressed longitudinal bars are arranged at intervals in the concrete base plate, and the length direction of the prestressed longitudinal bars is parallel to the length direction of the upper chord steel bars. Support steel bars are arranged at intervals on the upper part of the plane truss, and the length direction of the support steel bars is perpendicular to the length direction of the upper chord steel bars. The triangular supporting segments of the support steel bars are pressed on the upper chord steel bars of the plane truss, and the triangular supporting segments are fixedly connected to the upper chord steel bars. The horizontal connecting segments of the support steel bars are embedded in the concrete base plate, and the prestressed longitudinal bars are fixedly connected to the horizontal connecting segments.

2. The prestressed concrete flat steel bar truss composite slab according to claim 1, characterized in that: The thickness of the concrete base plate is not less than 35 mm.

3. The prestressed concrete flat steel bar truss composite slab according to claim 1, characterized in that: The diameter of the upper chord steel bar is 12 mm to 16 mm.

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