Precast concrete beam and preparation method thereof

Abstract

The prefabricated concrete beam comprises a steel beam piece, two sets of studs are welded to the upper surface of the steel beam piece in a mirroring mode with a middle web as the symmetry axis, the distances between the multiple studs in each set are the same, two sets of steel meshes are welded to the outer side points of steel flanges of the steel beam piece in a mirroring mode, and the steel meshes are welded to the outer side points of the steel flanges of the steel beam piece in a mirroring mode. The left end and the right end of the steel beam piece are each connected with an end sealing plate, and a plurality of mounting holes are evenly formed in the end sealing plates. The problems that concrete is prone to falling off and safety accidents are prone to being caused due to the fact that the edge of the assembly type precast concrete beam is subjected to external flushing and corrosion for a long time are solved.

Description

Technical Field

[0001] The present invention relates to the field of prefabricated building engineering, and in particular to a prefabricated concrete beam and a preparation method thereof. Background Art

[0002] Reinforced prefabricated concrete beams are prefabricated concrete beam components in the factory. During the production process, steel bars are placed in the concrete according to the design requirements to enhance the load-bearing capacity of the beam. These beams are cast in standardized molds in the factory, and after a certain period of curing, they reach the specified strength and are transported to the construction site for installation.

[0003] Compared with traditional on-site cast concrete beams, it has the characteristics of factory production, easier quality control and high production efficiency. Moreover, the configuration of its steel bars is accurately calculated according to the design force requirements, such as configuring more steel bars in the tensile zone of the beam to bear the tensile force, and configuring an appropriate amount of steel bars in the compressive zone to help the concrete bear the pressure.

[0004] Because it is a load-bearing component, the construction has high requirements on the strength of prefabricated concrete beams. In particular, the edges of prefabricated concrete beams are exposed to external washing and corrosion for a long time, which may cause concrete to fall off and cause safety accidents. Summary of the invention

[0005] The purpose of the present invention is to overcome the existing defects and provide a precast concrete beam and a preparation method thereof, which can ensure the strength of the beam and have good corrosion resistance, thereby improving safety.

[0006] The technical solution to achieve the above-mentioned purpose is: a precast concrete beam, including a steel beam member, the upper surface of the steel beam member is mirror-welded with two groups of bolts with the middle web as the symmetry axis, the spacing between multiple bolts in each group is the same, two groups of steel meshes are mirror-welded at the outer points of the steel flange of the steel beam member, the left and right ends of the steel beam member are respectively connected to a head plate, and a plurality of mounting holes are evenly opened on the head plate.

[0007] Preferably, the main beam connection of the steel beam members adopts the same type of overlap and is covered with a dense mesh steel wire mesh.

[0008] Preferably, the upper surface of the steel beam is poured with first concrete, the first concrete covers the entire upper surface of the steel beam, and the first concrete wraps around the lower half of each bolt.

[0009] Preferably, a fireproof layer is installed between the two steel meshes and the middle web of the steel beam, and a second concrete is poured on the outer sides of the two steel meshes. The material of the first concrete is UHPC concrete, the material of the second concrete is expanded clay foam concrete, and the material of the fireproof layer is Class A fireproof material.

[0010] Preferably, the steel beam is an H-shaped steel beam.

[0011] Preferably, the steel beam may also be a connecting piece of a T-shaped steel and a C-shaped steel, and the C-shaped steel is connected to a vertical plate of the T-shaped steel.

[0012] A method for preparing a precast concrete beam comprises the following steps: S1 prepares an H-shaped steel beam of appropriate size as a steel beam member, or welds a T-shaped steel and a C-shaped steel together to form a steel beam member; S2 welds two sets of studs on the upper surface of the steel beam; S3: Filling fireproof layers are installed on both sides of the middle web of the steel beam, and then two groups of steel meshes are installed on both sides of the steel beam, each group of steel meshes is close to the corresponding fireproof layer, and then the second concrete is poured around the periphery of each group of steel meshes until the second concrete completely seals the two fireproof layers; S4 finally uses the first concrete to cast the upper surface of the steel beam or the inner wall of the C-shaped steel for the second time.

[0013] The beneficial effects of the present invention are as follows: a plurality of bolts are installed on the upper surface of the steel beam, and a first concrete is poured; at the same time, a fireproof layer and two groups of steel meshes are successively installed on both sides of the steel beam, and a second concrete is poured; the material of the first concrete is UHPC concrete, which has extremely high compressive strength and corrosion resistance; this upper and lower double-layer pouring structure ensures the strength of the beam while having good corrosion resistance; and the installation of two groups of steel meshes can prevent the later coating concrete from cracking, thereby improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is an unassembled front view of the present invention; Figure 2 is a partial cross-sectional view of A in the present invention; Figure 3 It is a schematic diagram of the preparation of another embodiment of the present invention.

[0015] In the figure: 1. Steel beam; 2. Steel mesh; 3. First concrete; 4. Fireproof layer; 5. Second concrete; 6. Bolts; 7. Head plate. DETAILED DESCRIPTION

[0016] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0017] The present invention will be further described below in conjunction with the accompanying drawings.

[0018] Example 1 like Figure 1-2 As shown, a precast concrete beam includes a steel beam member 1, a plurality of bolts 6, two groups of steel wire mesh sheets 2 and two head plates 7.

[0019] Specifically, the steel beam 1 is an H-shaped steel beam, and two groups of bolts 6 are welded in a mirror image on the upper surface of the steel beam 1 with the middle web as the symmetry axis. The two groups of bolts 6 serve to connect the floor slabs and also serve to resist shear, thereby ensuring the stability of the structure; the spacing between the multiple bolts 6 in each group is the same, and two groups of steel meshes 2 are welded in a mirror image at the outer points of the steel flange of the steel beam 1. The two groups of steel meshes 2 are configured according to the calculation requirements of concrete crack resistance to prevent the second concrete 5 covered later from cracking; a head plate 7 is connected to each of the left and right ends of the steel beam 1, respectively, and the head plates 7 on both sides can prevent slurry leakage during pouring, and a plurality of mounting holes are evenly opened on the head plates 7 for connecting columns or main beams; the main beam connection of the steel beam 1 adopts the same type of overlap and a densely-hole steel wire mesh is laid on it to improve the stability of the main beam connection; Specifically, the upper surface of the steel beam 1 is poured with the first concrete 3, the first concrete 3 covers the entire upper surface of the steel beam 1, and the first concrete 3 wraps the lower half of each bolt 6. The material of the first concrete 3 is UHPC concrete, and the first concrete 3 has extremely high compressive strength and corrosion resistance, which greatly improves the safety of the structure; Specifically, a fireproof layer 4 is installed between the two steel meshes 2 and the middle web of the steel beam 1. The material of the fireproof layer 4 is A-class fireproof material. The fireproof layer 4 plays a fireproof role and improves the fireproof performance of the device. A second concrete 5 is poured on the outside of the two steel meshes 2. The material of the second concrete 5 is expanded clay foam concrete. The second concrete 5 can completely wrap the fireproof layer 4, thereby ensuring the overall stability and reducing the weight of the structure.

[0020] Example 2 Combination Figure 3Specifically, the steel beam 1 can also be a connecting part of T-shaped steel and C-shaped steel. The C-shaped steel is connected to the vertical plate of the T-shaped steel, the first concrete 3 is poured on the inner wall of the C-shaped steel, and two groups of steel meshes 2 are installed on the outer edges of the T-shaped steel and the C-shaped steel, which can facilitate the pouring of the first concrete 3.

[0021] Another aspect of the present invention provides a method for preparing a precast concrete beam, comprising the following steps: S1 prepares an H-shaped steel beam of appropriate size as the steel beam member 1, or welds a T-shaped steel and a C-shaped steel together to form the steel beam member 1; S2 welding two groups of studs 6 on the upper surface of the steel beam 1; S3: Filling fireproof layers 4 are installed on both sides of the middle web of the steel beam 1, and then two groups of steel meshes 2 are installed on both sides of the steel beam 1, each group of steel meshes 2 is close to the corresponding fireproof layer 4, and then the second concrete 5 is poured around the periphery of each group of steel meshes 2 until the second concrete 5 completely seals the two fireproof layers 4; S4 Finally, the upper surface of the steel beam 1 or the inner wall of the C-shaped steel is cast for the second time with the first concrete 3.

[0022] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some or all of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A precast concrete beam, characterized in that: The invention comprises a steel beam (1), wherein two groups of studs (6) are mirror-welded on the upper surface of the steel beam (1) with the middle web as the axis of symmetry, and the spacing between the plurality of studs (6) in each group is the same. Two groups of steel mesh sheets (2) are mirror-welded at points on the outer sides of the steel flanges of the steel beam member (1), and a head plate (7) is connected to the left and right ends of the steel beam member (1), respectively. A plurality of mounting holes are evenly arranged on the head plate (7).

2. The precast concrete beam according to claim 1, characterized in that: The main beam connection of the steel beam member (1) adopts the same type of overlap and is covered with dense mesh steel wire mesh.

3. The precast concrete beam according to claim 2, characterized in that: The upper surface of the steel beam (1) is cast with first concrete (3), the first concrete (3) covers the entire upper surface of the steel beam (1), and the first concrete (3) wraps around the lower half of each bolt (6).

4. The precast concrete beam according to claim 3, characterized in that: A fireproof layer (4) is installed between the two steel mesh sheets (2) and the middle web of the steel beam member (1), and a second concrete (5) is poured on the outer sides of the two steel mesh sheets (2). The material of the first concrete (3) is UHPC concrete, the material of the second concrete (5) is ceramsite foam concrete, and the material of the fireproof layer (4) is Class A fireproof material.

5. The precast concrete beam according to claim 1, characterized in that: The steel beam member (1) is an H-shaped steel beam.

6. The precast concrete beam according to claim 1, characterized in that: The steel beam member (1) may also be a connecting member of a T-shaped steel and a C-shaped steel, wherein the C-shaped steel is connected to a vertical plate of the T-shaped steel.

7. A method for preparing a precast concrete beam according to any one of claims 1 to 6, characterized in that: The steps include: S1 prepares an H-shaped steel beam of appropriate size as the steel beam member (1), or welds a T-shaped steel and a C-shaped steel together to form the steel beam member (1); S2 welding two groups of studs (6) on the upper surface of the steel beam (1); S3: filling fireproof layers (4) are respectively installed on both sides of the middle web of the steel beam (1), and then two groups of steel mesh sheets (2) are respectively installed on both sides of the steel beam (1), each group of steel mesh sheets (2) is closely attached to the corresponding fireproof layer (4), and then the second concrete (5) is poured around the periphery of each group of steel mesh sheets (2) until the second concrete (5) completely seals the two fireproof layers (4); S4 Finally, the upper surface of the steel beam (1) or the inner wall of the C-shaped steel is cast for a second time using the first concrete (3).

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