Prefabricated concrete bottom plate integrated with truss steel bars and prestressed steel wire meshes

Abstract

The invention discloses a prefabricated concrete bottom plate integrated with truss steel bars and a prestressed steel wire mesh, which comprises a concrete bottom plate, the middle layer of the concrete bottom plate is provided with a pre-tensioned steel wire mesh, and the upper end of the concrete bottom plate is provided with a plurality of groups of steel bar trusses which are transversely distributed at equal intervals; upper chord steel bars and lower chord steel bars are arranged at the upper ends and the lower ends of the steel bar trusses correspondingly, and the lower chord steel bars are embedded in the concrete bottom plate. The invention relates to a concrete bottom plate, in particular to a prefabricated concrete bottom plate integrating truss steel bars and a prestressed steel wire mesh, and belongs to the technical field of the building industry. According to the prefabricated concrete bottom plate, the problems of an existing concrete composite floor slab, an existing steel bar truss floor support slab and an existing prestressed steel pipe truss composite floor slab are solved, and in addition, due to the existence of the transverse slab bottom constructional steel bars and the transverse erecting steel bars on the upper chord portion of the steel bar truss, the prefabricated slab has the bi-directional stress characteristic; compared with an existing steel bar truss floor support plate, the prefabricated concrete bottom plate has larger transverse width.

Description

technical field [0001] The invention relates to a concrete floor, in particular to a prefabricated concrete floor integrating truss steel bars and prestressed steel wire mesh, and belongs to the technical field of construction industry. Background technique [0002] Prefabricated fiber concrete slab: a building slab produced by processing cement as the main raw material. It is a building product between gypsum board and stone, which can be cut, drilled and carved freely. It is superior to gypsum board and wood board. It has become a building material widely used in the construction industry due to its excellent fireproof, waterproof, anticorrosion, insect-proof, sound-proof properties, and the price is far lower than that of stone. The crack resistance of cement board can be enhanced by mixing glass fiber in the production process of cement board, forming Prefabricated fiber concrete slabs. [0003] Prefabricated composite steel mesh concrete slab: In the production process...

AI Technical Summary

Problems solved by technology

[0007] 1. In order to meet the requirements of building safety, the pre-embedded steel bars in the existing precast concrete laminated slabs usually need to protrude from the edge of the precast slab, which makes the production efficiency of the factory low and wastes molds; at the same time, it is extremely inconvenient to install on site

[0008] 2. The pre-embedded truss steel bars in the existing precast concrete laminated floor slabs often do not participate in the structural stress, but only play a role in enhancing the bite force between the precast slab and the cast-in-place laminated concrete. Therefore, the distance between the reinforced trusses Larger, the contribution to the bending stiffness of the slab is very limited, and the bottom of the slab needs to be supported by steel pipe scaffolding during on-site construction

[0009] 3. The prefabricated bottom slab is relatively thick, often accounting for more than 1 / 3 of the total thickness of the floor. Under a certain limit of the total slab thickness, the cast-in-place laminated layer is thinner, and the integrity of the floor slab is weaker, and it is in the cast-in-place laminated layer. Burying pipelines is very difficult

[0010] 4. There are two ways to splice the two slabs of the existing precast concrete laminated slabs: one is the separated type, that is, there is a distance of about 300mm between the two slabs, which is called the post-casting belt. The post-casting belt supports the formwork and binds the steel bars to pour the concrete. Therefore, the construction process is cumbersome and the cost is high. protruding from the edge of the slab), and then pouring the cast-in-situ laminated layer on the slab surface, due to the existence of splicing joints and the large thickness of the prefabricated bottom slab, the actual thickness of the floor slab at the slab seam is weakened to a large extent, which seriously affects the The strength and rigidity of the slab, the floor slab is easy to crack at the slab seam, affecting the normal use of the building

[0011] 5. In the prior art, ordinary concrete is used to make the prefabricated floor, and the thickness of the prefabricated floor is relatively thin, so the prefabricated floor is easy to crack during production and construction

[0012] 6. The thickness of the bottom slab of the precast concrete laminated floor is about 60mm or more, so the weight is relatively large, which is not conducive to transportation and hoisting

[0013] 7. In the prefabricated floor of the prior art, stress reinforcement bars in two directions are pre-buried. When the close-fitting technology is used, a large number of overlapping reinforcement bars need to be installed at the seam joints, and the amount of reinforcement bars is large, resulting in a lot of material waste.

[0016] 1. The bottom plate and the steel truss are only connected by welding or screws, and the integrity is poor. The bottom plate is only used as a bottom form and does not provide rigidity. In a larger space (span over 2.5m), the bottom of the slab still needs to be supported by steel pipe scaffolding during construction

[0017] 2. The galvanized steel plate affects the beauty of the building. If it is not removed, the room needs to be decorated and suspended. If it is removed, a construction process will be added, which will increase the cost accordingly

[0018] 3. If the galvanized steel plate and the truss steel are welded, it is easy to damage the galvanized layer of the galvanized steel plate at the welding point, and the place is easy to rust

[0019] 4. The bottom plate is only equipped with reinforced steel bars in one direction, that is, the steel bar truss. There is no steel bar in the other direction, resulting in weak rigidity and strength. The width of the plate is limited. Large quantity

[0020] 5. The steel truss floor deck adopts the steel mesh formwork as the bottom plate. During the production process, the steel mesh is bound or welded on the steel truss. The mesh formwork is not tight, and it is in a loose state in the early stage of stress, so it is impossible to accurately position the steel mesh. , and cannot effectively control the initial cracking of the concrete at the bottom of the slab

[0021] 6. The steel truss protrudes from the end of the plate and can be placed on the support, but it is actually only applicable to the steel structure beam. For the concrete structure beam, due to the influence of the stirrups and longitudinal bars on the beam, the steel truss cannot extend into the support Inside, the feature that the steel truss protrudes from the end of the plate reduces the efficiency of production and construction

[0023] 1. The bottom plate is too thin, and the fire protection time of the prestressed steel strand does not meet the requirements

[0024] 2. Prestressed steel strands and steel trusses are arranged in only one direction in the slab, and the stiffness and strength of the slab in the other direction are weak, and the slab width is limited

Images