JP2009002130A - Divertible opening form - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems that presently a void pipe without having draft angle nor flexibility is used for a form for an opening part provided on every floor for the purpose of equipment-piping in a reinforced concrete high-storied building, which turns out to require quite much labor in mounting it as well as in removing the form after concrete is solidified and that it cannot be diverted because of being broken on that occasion and thus is disposed as an industrial waste while in a series of plastering work, since it is projected from a finished surface of a slab, it becomes hindrance for the work and thus work efficiency is decreased. <P>SOLUTION: In order to remove the opening form easily and without damaging from the hardened concrete, a polyvinyl chloride pipe having a notch in a trunk part of a cylindrical shape in the axial direction for allowing self-contraction property is used. Accordingly, the divertible opening form can easily be disassembled while at the same time the total height of the form is a little lower that the thickness of the slab, so as not to be an obstacle in a series of plastering work. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a floor opening formwork for piping for facilities penetrating each floor in a reinforced concrete high-rise building.

  Conventionally, a so-called void tube was used as a formwork for opening the floor, and a nail was cut diagonally and fixed in place so that it would not move when placing ready-mixed concrete after being cut slightly longer than the slab thickness. is doing. After that, after the concrete has solidified, the void pipe used as the formwork will be removed, but this void pipe has no draft, so it cannot be easily removed, especially if the slab is thicker. In addition to annoying the worker, the void tube debris that was damaged when removed must be treated as industrial waste.

As described above, an open mold using a void tube has no draft and has a certain rigidity. It cannot be removed without damage. Therefore, not only a considerable amount of labor is required to remove the formwork, but also the broken formwork cannot be diverted and is treated as waste.
Also, until the construction of the upper floor of the work floor is completed, thin veneers, etc. are blocked with concrete nails to prevent rainwater from flowing into the void pipe holes, but they cannot be completely blocked. It is an obstacle for interior work on the lower floor, which is performed in parallel.
The present inventor has come to consider that it is extremely beneficial to solve the above-mentioned problems by providing a slab opening mold having a structure that can be easily removed and diverted.

  As a result of diligent research, the present inventor has been able to remove the slab opening formwork from the solidified concrete very easily without damaging the slab opening formwork in the conventional construction method using a panel for the slab formwork. We have succeeded in developing a useful and useful formwork to make it work.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is an image view of a divertable opening formwork for a slab conventional method according to the present invention. Here, reference numeral 1 is an upper lid of the mold, which holds the outer diameter of the plastic cylinder body of reference numeral 2 that is to be self-contracted and prevents the ready-mixed concrete from flowing into the cylinder during placement. It is a resin plate. Reference numeral 3 denotes a head of a long wood screw for fixing the opening mold to a panel which is a slab mold. Reference numeral 4 is a cut for self-contracting the cylindrical portion of reference numeral 2 when the upper cover of reference numeral 1 is removed.
FIG. 2 is a cross-sectional view of the formwork, where reference numeral 5 is a generally triangular resin plate for controlling the self-shrinkage of the lower part of the cylindrical body, and the long wood screw passes through the central part thereof. It has a hole.
FIG. 3 is a sectional view of the cylindrical portion. FIG. 3A shows a state in which a predetermined inner diameter is held by upper and lower plate codes 1 and 5. Similarly, (b) shows a state when the plate is removed, and the inner diameter is reduced by self-contraction. In order to make this self-shrinking smooth, the cutting angle is about 45 degrees with respect to the radial direction as shown in the figure.
FIG. 4 is a cross-sectional view of the opening formwork when it is attached to an actual site. Reference numeral 6 denotes a control panel that is a formwork of a slab. Reference numeral 7 denotes cast-in concrete, and as shown in the figure, the open mold is constructed to be slightly lower than the slab thickness. As a result, the thickness of the concrete on the top cover is about several millimeters while it does not become an obstacle during a series of plastering operations, so it can be removed by tapping with a small hammer, and the opening formwork can be easily removed in order from the top. Can be dismantled. In addition, it is possible to completely prevent rainwater from flowing into the lower floor by not performing this dismantling work until the construction of the upper floor slab is completed.

  If the opening formwork according to the present invention is used as described above, it is possible to divert without using time and labor for installing the opening formwork or for removing the mold after solidification as before, and without damaging the formwork. Reduce the generation of industrial waste. In addition, it can bring about great economic effects such as completely preventing rainwater from entering the lower floor.

The placement test of the product of the present invention was carried out at a site of a double reinforced concrete structure having a slab thickness of 250 mm, a main reinforcing bar and a reinforcing bar of D13, and a pitch of 150 mm.
A PVC pipe having an inner diameter of 100 mm was used for the cylindrical portion of the open mold as the product of the present invention used in this test. Further, a resin plate having a thickness of 3 mm was used for the upper lid, and the total height of the mold including the plate was manufactured at 245 mm. Therefore, the upper surface of the formwork was buried 5 mm from the cast concrete.
As a result of conducting tests on the three openings under the above conditions, the construction was carried out without any obstacle to the series of plastering operations at the time of placing in any part.
Moreover, in the dismantling and removal work of the formwork after solidifying the slab concrete, the upper concrete of the formwork can be removed only by tapping with a hammer, and then a series of steps from removal of the top cover and bottom plate to removal of the PVC pipe are performed. It was confirmed that the work was carried out smoothly without damaging all the three forms, and was used for diversion.

  Image of open mold according to the present invention   Sectional view of FIG.   (A) and (b) are cross-sectional views of the cylindrical portion.   Sectional view when an open mold is attached

Explanation of symbols

1. Resin top cover 2. Resin cylinder 3. Nagaki screw 4. Cylindrical notch 5. Resin bottom plate 6. Control panel 7. Casting concrete.

Claims (1)

A generally cylindrical formwork for providing an opening in a floor for piping for equipment passing through each floor in a conventional reinforced concrete building, and the cylinder so that it can be easily removed after solidification of concrete One part of the body is cut over the entire length in the axial direction, and the cut is made at an angle of several tens of degrees with respect to the radial direction of the cylindrical body. Therefore, in order to maintain the inner diameter before cutting of the cylindrical body, when the substantially plate-like lids attached to the upper and lower end faces of the cylindrical body are removed, the cylindrical body reduces its inner diameter due to its contractibility, and solidified concrete Since a slight gap is formed between the two, it can be easily extracted without being damaged and can be diverted for use.
Further, the cylindrical opening form is characterized by being made about several millimeters shorter than a predetermined slab thickness, and does not become an obstacle to a series of plastering operations such as leveling and pressing from the ready-mixed concrete. A method of pressing the opening mold from above the plate-shaped upper lid using a metal piece having a wood screw processed at the tip slightly longer than the opening mold to fix the slab mold to the panel. Similarly, fix the plate-like lower lid to the slab form panel with short wood screws first, install the cylindrical body and upper lid on it, and then attach the lid and lower lid with an iron wire etc. A divertable opening mold as described above having a method of binding.

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