JPH035101A - Manufacture of half pca slab - Google Patents

Abstract

PURPOSE:To enable inexpensively shortening of a manufacturing period, by a method wherein a sheet into which a large number of cotter molds are arranged while concrete is not hardened is laid on the surface and the second concrete is placed on the sheet. CONSTITUTION:An ambient concrete shuttering 2 for manufacturing of a half precast concrete (PCa) slab is set up on a bed 1 and concrete 3 for the first layer half PCa slab is placed within the ambient concrete shuttering 2. A vinyl sheet 4 is laid in succession on the surface of the concrete 3 at an early stage possible, where the concrete 3 is not hardened, on which concrete 5 for the second layer half PCa is placed. The inside of cotter molds 4a arranged large in number on the vinyl sheet 4 is hollow and is resistable against shearing force. The sheet with the cotter molds is pressed against lower layer concrete with a weight of the upper layer concrete, the cotter can be formed reliably and easily and two layers of the PCa slabs can be manufactured at the same time.

Description

[Detailed description of the invention] [Field of application in industry 1] The present invention is directed to half PCa (precast concrete)
This invention relates to a method for manufacturing a board.

[Prior art] In general, half P Ca board has 1 plate as shown in FIG.
Concrete 1, 1'1' for the entire beam or the upper end of the beam is installed at the same time as concrete 1, 1'1' for the entire beam or the upper end of the beam.
．． 1 has been made into a book.

In this way, the half PCa board 12 is provided with a large number of pitchers 1.2a on its surface in order to be integrated with the cast-in-place casters 1 and 11.

Conventionally, in order to manufacture this kind of half PCa board, as shown in FIG.
4 and pour concrete 15 into it,
A cotter is formed on the surface of the half PCa board by pressing a plywood 16 with a large number of cotter molds 16a as shown in FIG. It was manufactured by laminating half PCa plates.

[Problems to be Solved by the Invention] This method of laminated manufacturing of half PCa boards can effectively utilize the site site. Excellent.

However, with the above conventional method, not only is it difficult and time-consuming to push the plywood (=1) onto the concrete surface, but the next concrete must be poured and stacked until the concrete has hardened. Since it is not large, it takes a lot of time to make it, and there are problems such as the overall costume costing 1.

The present invention was made in order to solve the problems of the conventional art described in I-1, and its purpose is to provide a method for manufacturing a half PCa board that is inexpensive and can shorten the manufacturing period. .

[Means for Solving the Problems 1] The method for manufacturing a half PCa board of the present invention includes pouring concrete 1 for the first half PCa board in the surrounding formwork, and pouring a large number of concretes before the concrete hardens. This method is characterized by laying a sheet on which the cotter molds of 1 and 2 are arranged on the surface of concrete, and pouring concrete for the half PCa board of tjS2 on the sheet.

[Embodiment 1] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In Fig. 1, a surrounding formwork 2 made of half-P Ca board is set on a bed 1''2, and a first
Concrete 3 for the half-layer PCa board is poured.

Next, as soon as possible before the concrete 3 hardens, as shown in FIG. 2, a vinyl sheet 4 is laid on the surface of the concrete 3, and as shown in FIG. , 2nd NJ half PCa
Pour concrete 5 for the board.

As is clear from FIG. 4, a large number of cotter molds 4a are arranged on the vinyl sheet 4. As shown in the enlarged drawing tIfJ5, the inside of the cotter mold 4a is hollow, but it may be filled with, for example, a 7-ohm polyurethane material. Further, the shape of the cotter mold 4a is not limited to a circular shape, but may be any shape as long as it can resist shearing force.

The surface of the concrete 5 is finished flat using a metal trowel or the like.

``After the concretes 3 and 5 described in Section 2 have hardened,'' repeat the process described in Section 2 above to manufacture the 3N and 4th layer half PCa plates (not shown), and then sequentially form a large number of half PCn plates. are manufactured in a laminated state.

[Effects of the Invention] (1) Since two layers of PCa plates can be manufactured at the same time, the manufacturing time can be shortened compared to the conventional method.

(2) The weight of the upper layer of concrete pushes the corer molded sheet onto the lower layer of concrete, thereby making it possible to reliably and easily form the corer.

(3) It can be manufactured at a low cost simply by using a sheet with a cotter pattern.

[Brief explanation of drawings]

Figures 1 to 3 are cross-sectional views sequentially illustrating the method of manufacturing a half PCa board of the present invention, Figure 4 is a plan view of the vinyl sheet, Figure 5 is an enlarged cross-sectional view of the cotter-shaped portion, and Figure 6 is the half PCa board manufacturing method of the present invention. A perspective view of an example of the use of a PCa board, and FIGS. 7 and 8 are illustrations of a conventional manufacturing method. 1... Base, 2... Surrounding formwork, 3 Concrete - 1.
, 4... Vinyl sheet, 4a... Cotter type, 5
···concrete.

Claims (1)

[Claims] Concrete for the first half PCa board is placed in the surrounding formwork, and before the concrete has hardened, a sheet with a large number of cotter molds arranged is laid on the surface of the concrete, and a second sheet is placed on the surface of the concrete. Half PCa characterized by pouring concrete for half PCa board of
Method of manufacturing the board.