JPH04348906A - Manufacture of precast concrete beam - Google Patents

Abstract

PURPOSE:To manufacture a precast concrete beam by only installing a mold frame on one side of a beam to be manufactured and perform both pre-fabrication and post-fabrication of iron bars, and improve the workability and economic benefit. CONSTITUTION:On the H-shaped steel material superimposed on the unfloored concrete 1 constituting a beam manufacturing mold frame bed, a pair of bracket mold frames 3 are movably installed, and only first precast concrete beam A1 is manufactured between the opposite mold frames 3, 3, and beams A2, A3 following the second are manufactured by taking advantage of the concrete placing surface of the precast concrete beam demolded in the prior process, by the use of the mold frame 3 for only one surface, and then by reverse-using the mold frame 3, with the result that a precast concrete beam can be manufactured by only installing the mold frame 3 on one side of the beam.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing precast concrete beams used for constructing concrete frames in construction work.

0002

[Prior Art] Conventionally, when manufacturing precast concrete beams, formwork is set on both sides of a single precast beam using pallets at predetermined intervals, and the formwork is assembled, tightened, and concreted using formwork fasteners such as form ties. The process of construction and dismantling was repeated.

0003

[Problem to be solved by the invention] In the conventional construction method, formwork is assembled on both sides of all beams, so
It requires a large amount of material, takes time to assemble, increases manufacturing costs, and has limitations in the manufacturing process, such as the need to assemble reinforcing bars first due to the use of separators in the formwork. Ta.

The present invention was proposed in view of the problems of the prior art, and its purpose is to make it possible to manufacture precast concrete beams by simply installing formwork on one side of the beam. , reinforcing bars can be assembled both first and second.
The object of the present invention is to provide a method for manufacturing a precast concrete beam with improved workability and economical efficiency.

[0005]

[Means for Solving the Problems] In order to achieve the above object, according to the method for manufacturing a precast concrete beam according to the present invention, the steel material constituting the bottom of the form is layered on the bed, and the steel material constituting the bottom of the form is layered on the bed. A pair of opposing bracket formworks are installed movably, and the first precast concrete beam is manufactured by installing both formworks at beam width intervals and pouring concrete into both formworks. The bracket form is moved along the steel material, concrete is poured between the form and the poured concrete surface of the first precast concrete beam, and the above steps are repeated.

[0006]

[Operation] According to the present invention, the steel material constituting the bottom of the formwork is layered on the production bed of the precast concrete beam, and the bracket formwork is movably installed on the steel material, and only the first precast beam is made of the same material. It is manufactured by pouring concrete between the two bracket formworks located on both sides of the beam, and for the next precast beam, the concrete pouring surface of the precast beam that has been removed from the mold is used, and the same pouring surface and the bracket mold are used. By placing concrete between the beam and the frame, it is possible to manufacture a precast concrete beam by simply installing the formwork on one side of the beam.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. The earthen floor concrete 1 constituting the manufacturing bed of the precast concrete beam is poured and finished with a metal trowel to improve level accuracy. Next, H-shaped steel members 2 are arranged in rows at predetermined intervals on the concrete 1 as steel members constituting the bottom of the formwork, and on the H-shaped steel members 2, a weir plate such as a plywood board is placed on the inner surface of the vertical piece 3a. A pair of opposing angle-shaped bracket formworks 3 on which the brackets 4 are layered are arranged,
The horizontal piece 3b of the formwork 3 is configured to be fastened to the upper flange of the H-shaped steel member 2 via a fastening fitting 5, and a plywood board 6 that will become the bottom of the beam is set on the formwork 3.

[0008] When manufacturing a precast concrete beam, the first precast concrete beam A1
Only when manufacturing the beam, the pair of formworks 3 are arranged on both sides of the beam at intervals equal to the predetermined beam width, and are fixed to the H-shaped steel material 2 via the fastening fittings 5. Next, the beam reinforcing bars 7 are set in both forms 3, formwork (not shown) for the edge of the beam is attached, and concrete 8 is poured.

After hardening of the poured concrete 8, the tightening of each of the formworks 4 and the H steel material 2 by the fastening fittings 5 is released, and the distance between the precast concrete beam A1 and the concrete pouring surface is equal to the beam width. The bracket is moved in the direction of the arrow in FIG. 1 until it is equal to In the meantime, beam reinforcing bars 7 are arranged in the same manner as described above, formwork for the edge portion is attached, and concrete 8 is cast, thereby manufacturing second and third precast concrete beams A2 and A3. At this time, a vinyl film 9 is attached to the concrete casting surface of the precast concrete beam to prevent adhesion to the concrete.

0010

According to the present invention, as described above, a pair of bracket formworks are movably installed facing each other on the steel material constituting the bottom of the formwork layered on the bed, and Only cast concrete beams are manufactured between a pair of opposing bracket forms located on both sides of the beam,
From the second precast concrete beam, the precast concrete beams are successively made by using the casting surface of the beam demolded in the previous process, using the bracket formwork on one side only, and reusing the same formwork repeatedly. Therefore, it can be manufactured by simply installing the formwork on one side of the beam, greatly reducing the amount of formwork materials, making it easy to fix the formwork, simplifying assembly time, and making it easier to manufacture. Cost savings.

Furthermore, since it is not necessary to use a separator in assembling the formwork, it is possible to apply both pre-assembly and post-assembly methods when arranging reinforcement.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view showing the implementation status of an embodiment of the method for manufacturing a precast concrete beam according to the present invention.

FIG. 2 is a partially enlarged view of FIG. 1;

[Explanation of symbols]

1　　　　　Earth floor concrete 2 H type steel material 3 Bracket formwork 5 Tightening metal fittings 7 Beam reinforcement 8 Concrete 9 Vinyl film

Claims (1)

[Claims] Claim 1: The steel materials constituting the bottom of the formwork are layered on the bed, and a pair of opposing bracket formworks are movably installed on the bed, and both the formworks are first installed at beam width intervals. A first precast concrete beam is manufactured by pouring concrete in both formworks, and then the bracket formwork is moved along the steel material, and concrete is poured in the formwork and the first precast concrete beam. 1. A method for manufacturing a precast concrete beam, characterized by pouring concrete between the beam and the surface, and repeating the steps described above.