Assembled integral type large-span hollow floor system based on prefabricated prestressed beams

Abstract

The invention discloses an assembled integral type large-span hollow floor system based on prefabricated prestressed beams, which comprises the prefabricated prestressed concrete beams which can directly span the span of the floor system and are spliced with each other, the prefabricated prestressed concrete beam is composed of a horizontal upper flange, a horizontal lower flange and a beam web, the horizontal upper flange and the horizontal lower flange are arranged along the span of the floor system, the beam web is vertically connected with the horizontal upper flange and the horizontal lower flange, and the horizontal lower flange of the prefabricated prestressed concrete beam is provided with an abutted seam connecting piece and a transverse penetrating steel bar. The adjacent prefabricated prestressed concrete beams are transversely spliced along the span through the abutted seam connecting pieces and the transverse penetrating steel bars, cast-in-place longitudinal ribs are formed in a formed abutted seam area through cast-in-place concrete, and cast-in-place transverse ribs which are evenly distributed at equal intervals are formed in the mode of being perpendicular to the prefabricated prestressed beams through cast-in-place concrete. The risk that concrete pouring of the lower flange of the cast-in-place concrete hollow floor is not compact and segregated is solved, the risk that a filling body of the cast-in-place concrete hollow floor floats upwards is thoroughly eliminated, the integrity of the hollow floor and the construction quality of a concrete structure are guaranteed, and the anti-permeability performance is improved.

Description

Technical Field

[0001] The invention relates to a concrete hollow floor structure, in particular to an assembled integral large-span hollow floor based on prefabricated prestressed beams. Background Art

[0002] Hollow floor is a kind of cast-in-place reinforced concrete hollow floor; also called cast-in-place beamless hollow floor, which is a hollow floor without visible beams cast in place after installing the core mold product. Hollow floor includes steel bars, concrete, and core molds. The core molds are buried in reinforced concrete, and the core molds are lightweight materials with low apparent density. Cast-in-place concrete hollow floor is an effective means to solve the design of large-span floor structures. It has the advantages of high bending stiffness, small structural height, fast construction, and relatively low comprehensive cost. However, when lightweight filling bodies are used, it is very easy to float, resulting in uncontrollable thickness of the upper and lower flanges of the hollow floor section, displacement of steel bars, and then cracking of concrete and even affecting the bearing capacity safety of the floor; when heavier filling bodies are used, the deadweight of the structure will increase, reducing the technical and economic advantages of the hollow floor; in addition, due to the influence of the filling body covering, when the thickness of the lower flange is thin, there is a risk of pouring quality such as the fullness and uniformity of the concrete. In addition, cast-in-place concrete hollow floor slabs also use a large number of supports and consumable formwork, generating a large amount of construction waste, which is extremely detrimental to energy conservation, emission reduction and environmental protection.

[0003] Therefore, it is necessary to solve the risks of loose pouring and segregation of concrete at the lower flange of cast-in-place concrete hollow floor slabs, completely eliminate the risk of floating of the filling body of cast-in-place hollow floor slabs, reduce the deadweight of the structure, and reduce the project cost. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide an assembled integral large-span hollow floor based on prefabricated prestressed beams, to solve the risks of loose casting and segregation of concrete at the lower flange of cast-in-place concrete hollow floor, to completely eliminate the risk of floating of the filling body of the cast-in-place hollow floor, to reliably ensure the integrity of the hollow floor and the construction quality of the concrete structure, to achieve the same anti-seepage performance as the cast-in-place floor structure, and to completely avoid the use of vertical supports and consumable formwork within the span of the floor, which is beneficial to environmental protection and reducing carbon emissions, while reducing the deadweight of the structure and reducing the project cost.

[0005] The prefabricated prestressed beam-based assembled integral large-span hollow floor slab of the present invention comprises prefabricated prestressed concrete beams that can directly span the span of the floor slab and be spliced ​​with each other. The prefabricated prestressed concrete beams are composed of a horizontal upper flange, a horizontal lower flange, and a beam web vertically connecting the horizontal upper flange and the horizontal lower flange, and the horizontal lower flange of the prefabricated prestressed concrete beam is provided with a joint connector and a transverse through-steel bar, and adjacent prefabricated prestressed concrete beams are transversely spliced ​​along the span through the joint connector and the transverse through-steel bar;

[0006] Further, the joint connector is a cross-sectional L-shaped structure provided at the joint end of the horizontal lower flange, the vertical side of the L-shaped structure is connected to the horizontal lower flange, and the horizontal side is butted at the joint;

[0007] Further, the horizontal edge of the joint connector is arranged flush with the bottom edge of the horizontal lower flange, and the transverse through-steel bars of the horizontal lower flange are butted against the top of the joint connector;

[0008] Further, the joint connector is made of cement material, and the joint connector is integrally formed with the horizontal lower flange;

[0009] Further, cast-in-place concrete is cast in the joint area to form cast-in-place longitudinal ribs, and cast-in-place concrete is cast in-place perpendicular to the prefabricated prestressed beam to form evenly spaced cast-in-place transverse ribs, and the cast-in-place longitudinal ribs and cast-in-place transverse ribs are both provided with steel bars;

[0010] Further, the horizontal lower flange is wider than the horizontal upper flange, a lightweight filler is arranged on the horizontal lower flange, the lightweight filler is located between the beam web, the cast-in-place longitudinal ribs and the cast-in-place transverse ribs, and then steel bars are laid and concrete is poured to form an upper flange plate as a whole with the horizontal upper flange;

[0011] Furthermore, a plurality of reinforcing steel bars are arranged at intervals along the span range at the bottom of the web, stirrups are reserved at the top of the precast prestressed concrete beam, and the steel bars at the bottom of the cast-in-place transverse ribs pass through the reinforcing steel bars holes and form a complete steel bar skeleton structure with the steel bars at the top and the reserved stirrups;

[0012] Furthermore, the upper flange has an inverted trapezoidal cross-section.

[0013] The beneficial effects of the present invention are as follows: the prefabricated prestressed concrete beams directly span the span of the floor slab, so that there is no need to set vertical supports within the span range, and the prefabricated prestressed concrete beams are spliced ​​and anchored transversely along the span through transverse steel bars and joint connectors, and the horizontal edges of the joint connectors can be used as cast-in-place concrete bottom templates and permanently retained in the main structure as a steel bar protective layer, and the cast-in-place longitudinal ribs, cast-in-place transverse ribs and upper flange plate concrete are cast-in-place at one time, and the cast-in-place longitudinal ribs and The steel bars in the cast-in-place transverse ribs, the steel bars in the upper flange plates, and the longitudinal steel bars and stirrups of the precast prestressed concrete beams are crossed with each other, and the transverse steel bars of the horizontal lower flange are anchored in the cast-in-place longitudinal rib concrete in the joint joint area, so as to realize the integral combination of cast-in-place concrete and precast prestressed beams. It not only realizes the assembled integral prestressed hollow floor system with zero support and zero formwork, but also realizes the anti-seepage performance equivalent to the cast-in-place floor structure, and completely avoids the various risks brought by the floating of the filling body, while being conducive to reducing the deadweight of the structure and reducing the project cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0015] Figure 1 It is the cross-sectional view of precast prestressed beams, where a is the side beam precast beam and b is the standard precast beam;

[0016] Figure 2 This is the side elevation view of the precast prestressed beam;

[0017] Figure 3 Assemble the plan layout of the integral hollow-core floor structure for precast prestressed beams;

[0018] Figure 4 It is the plan layout of beams and infills;

[0019] Figure 5 for Figure 4 1-1 sectional view;

[0020] Figure 6 for Figure 4 2-2 sectional view;

[0021] Figure 7 The schematic diagram of the reinforcement of the upper flange plate of the precast prestressed beam;

[0022] Figure 8 for Figure 7 3-3 sectional view;

[0023] Fig. 9 for Figure 7 Sectional view 4-4. DETAILED DESCRIPTION

[0024] The assembled integral large-span hollow floor based on precast prestressed beams of this embodiment includes precast prestressed concrete beams 1 that can directly span the span of the floor and be spliced ​​with each other. The precast prestressed concrete beams 1 are composed of a horizontal upper flange 101, a horizontal lower flange 102 and a beam web 103 vertically connecting the horizontal upper flange 101 and the horizontal lower flange 102, which are arranged along the span of the floor. The horizontal lower flange 102 of the precast prestressed concrete beam 1 is provided with a joint connector 105 and a transverse through-steel bar 104. Adjacent precast prestressed concrete beams 1 are transversely spliced ​​along the span through the joint connector 105 and the transverse through-steel bar 104. The length of the precast prestressed concrete beam 1 is the same as the clear span of the floor, and is transversely spliced ​​in the plane formed by the frame main beam and the frame secondary beam. The precast prestressed concrete beam 1 is prefabricated with main reinforcements embedded in the horizontal lower flange 102. The main reinforcements include large-diameter main reinforcements 106 (including prestressed reinforcements) located below the web, and small-diameter main reinforcements 107 in the rest of the area, all of which are evenly spaced along the longitudinal direction of the span. The horizontal lower flange 102 of the precast prestressed concrete beam 1 is also provided with transverse through-steel bars 104 (along the transverse direction of the span), which extend out of the end of the horizontal lower flange 102. Adjacent precast prestressed concrete beams 1 are arranged transversely along the span and connected in the joint 4 through the transverse through-steel bars 104 and the joint connectors 105. The joint connectors 105 can be used as the bottom formwork for cast-in-place concrete, and remain in the joint 4 after casting and forming, and are permanently retained in the main structure concrete as a steel bar protective layer. Since the precast beams are spliced ​​by the side frame precast beams 11 and the standard precast beams 12, the joint connector 105 is only provided at one end of the side frame precast prestressed concrete beams, while the joint connector 105 is provided at both ends of the standard precast prestressed concrete beams.

[0025] In this embodiment, the joint connector 105 is a cross-sectional L-shaped structure arranged at the splicing end of the horizontal lower flange 102, the vertical side of the L-shaped structure is connected to the horizontal lower flange 102, and the horizontal side is butted at the joint 4; the vertical side of the L-shaped structure serves as the frame of the precast prestressed concrete beam 1, and the horizontal side serves as the splicing end, and after the two adjacent horizontal sides are aligned and spliced, a "V-shaped" notch is formed at the splicing, so that after pouring concrete, cement slurry can fill the entire thickness of the horizontal side of the connector, and at the same time it is used as the bottom formwork of cast-in-place concrete and anchored in the concrete. The structure has strong integrity and plays a strengthening role.

[0026] In this embodiment, the horizontal edge of the seam connector 105 is arranged flush with the bottom edge of the horizontal lower flange 102, and the transverse through-steel bars 104 of the horizontal lower flange 102 are connected to the top of the seam connector 105; after anchoring, the horizontal edge of the seam connector 105 can serve as a protective layer for the transverse through-steel bars 104.

[0027] In this embodiment, the joint connector 105 is made of cement material, and the joint connector 105 is integrally formed with the horizontal lower flange 102; it is made of high-performance cement material, and its strength and durability are much higher than prefabricated prestressed beam concrete.

[0028] In this embodiment, cast-in-place concrete is cast in the joint area to form cast-in-place longitudinal ribs 2, and cast-in-place transverse ribs 3 are cast in-place perpendicular to the prefabricated prestressed beam 1 to form evenly spaced cast-in-place transverse ribs 3, and both cast-in-place longitudinal ribs 2 and cast-in-place transverse ribs 3 are provided with steel bars; the area separated between the cast-in-place transverse ribs 3 and the cast-in-place transverse ribs 3 is used as the setting area of ​​the lightweight filling body 8. The construction of the entire structure does not require support and formwork, giving full play to the advantages of convenient and fast assembly construction, and obtaining good results in terms of integrity and waterproof performance of the cast-in-place structure; the setting and binding of the steel bars in the cast-in-place longitudinal ribs 2 and cast-in-place transverse ribs 3 adopt the conventional methods of the prior art.

[0029] In this embodiment, the horizontal lower flange 102 is wider than the horizontal upper flange 101, and a lightweight filler 8 is arranged on the horizontal lower flange 102. The lightweight filler 8 is located between the beam web 103, the cast-in-place longitudinal ribs 2 and the cast-in-place transverse ribs 3. Then, steel bars are laid and concrete is poured to form an upper flange plate with the horizontal upper flange 101 as a whole. The plate reinforcement 1021 of the upper flange plate is distributed as follows: Figure 7 As shown, it is only necessary to set the steel bars in the transverse and longitudinal directions; a plurality of reinforcing holes 108 are arranged at intervals along the span range at the bottom of the web 103, stirrups are reserved at the top of the precast prestressed concrete beam 1, and the steel bars at the bottom of the cast-in-place transverse rib 3 pass through the reinforcing holes 108, and form a complete steel skeleton structure with the steel bars and reserved stirrups at the top. The lightweight filler 8 is located under the steel bars, and adopts a two-way double layer or single layer, so the problem of the lightweight filler floating can be solved. At the same time, the filler body is used at the joint 4 to facilitate the formation of the cast-in-place longitudinal rib 2. At the same time, the reinforcing holes at the bottom of the web 103 of the precast prestressed beam are used to facilitate the formation of the cast-in-place transverse rib 3, which minimizes the self-weight of the precast prestressed beam and makes the structure have obvious spatial working performance or two-way force characteristics.

[0030] In this embodiment, the upper flange 101 has an inverted trapezoidal structure in cross section; the cast-in-place longitudinal ribs 2, cast-in-place transverse ribs 3 and upper flange 101 concrete combine the precast prestressed beam lower flange 102, upper flange 101 and beam web 103 into a complete whole, forming an assembled integral hollow floor, while achieving the technical advantages of zero support and zero formwork in the span range of the floor.

[0031] In this embodiment, it is finally explained that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention is described in detail with reference to the preferred embodiments, a person skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An assembled integral large-span hollow floor based on prefabricated prestressed beams, characterized in that: It comprises prefabricated prestressed concrete beams which can directly cross the span of a floor slab and be spliced ​​with each other. The prefabricated prestressed concrete beams are composed of a horizontal upper flange, a horizontal lower flange and a beam web vertically connecting the horizontal upper flange and the horizontal lower flange. The horizontal lower flange of the prefabricated prestressed concrete beam is provided with a joint connector and a transverse through-steel bar. Adjacent prefabricated prestressed concrete beams are transversely spliced ​​along the span through the joint connector and the transverse through-steel bar.

2. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 1, characterized in that: The joint connector is an L-shaped structure with a cross section arranged at the joint end of the horizontal lower flange. The vertical side of the L-shaped structure is connected to the horizontal lower flange, and the horizontal side is butted at the joint.

3. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 2, characterized in that: The horizontal edge of the joint connector is flush with the bottom edge of the horizontal lower flange, and the transverse through-steel bars of the horizontal lower flange are butted against the top of the joint connector.

4. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 3, characterized in that: The joint connector is made of cement material and is integrally formed with the horizontal lower flange.

5. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 1 is characterized in that: Cast-in-place concrete is cast in the joint area to form cast-in-place longitudinal ribs; cast-in-place concrete is cast perpendicular to the precast prestressed beam to form evenly spaced cast-in-place transverse ribs, and both the cast-in-place longitudinal ribs and the cast-in-place transverse ribs are provided with steel bars.

6. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 5 is characterized in that: The horizontal lower flange is wider than the horizontal upper flange, and a lightweight filling body is arranged on the horizontal lower flange. The lightweight filling body is located between the beam web, cast-in-place longitudinal ribs and cast-in-place transverse ribs, and then steel bars are laid and concrete is poured to form an upper flange plate as a whole with the horizontal upper flange.

7. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 6 is characterized in that: The bottom of the web is provided with a plurality of reinforcement holes at intervals along the span, stirrups are reserved at the top of the precast prestressed concrete beam, and the steel bars at the bottom of the cast-in-place transverse ribs pass through the reinforcement holes and form a complete steel skeleton structure with the steel bars at the top and the reserved stirrups.

8. The assembled integral large-span hollow floor based on prefabricated prestressed beams according to claim 7 is characterized in that: The upper flange has an inverted trapezoidal cross section.

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