GB2420567A

GB2420567A - Modular shuttering system

Info

Publication number: GB2420567A
Application number: GB0426132A
Authority: GB
Inventors: Michael Purdy
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-11-27
Filing date: 2004-11-27
Publication date: 2006-05-31
Anticipated expiration: 2024-11-27
Also published as: GB0426132D0; GB2420567B

Abstract

A form for use in a beam and block flooring system comprises a sheet having a base with two opposed sidewalls projecting therefrom. The walls can be folded so that they are perpendicular with the base. The base has push-out pieces 5 which are used as struts when received in the sidewalls, preferably in slits 7. The ends 8 of the sidewalls preferably conform to the profile of a beam. End walls may be provided, which may also have push-out pieces which can be used as struts. The sidewalls may further comprise an aperture and pre-cut self-closing flap 9 to allow the form to be filed with foam. The sheet material may comprise a corrugated plastics material such as polypropylene. The form may be used in a system further comprising a beam grip and a corrugated or pleated sheet which may sit atop the grip to fill a cavity between beams and blocks with foam.

Description

1 2420567 A modular shuttering system This invention relates to a modular

shuttering system for use with the beam & block flooring systems widely used in the construction industry. These systems consist of a series of pre-cast concrete beams which are set out parallel to each other, with the spaces between them filled with standard pre-cast concrete building blocks. The depth of the beams can vary depending upon their span.

These beams vary in design depending upon the manufacturer, but viewed in cross section they are all symmetrical. They all allow for a standard concrete block to rest upon a ledge resulting in the top of the block sitting flush with the top of the beam. The beams do not have ledges on their end sections as they are manufactured in long lengths and are cut to size as required. Usually supported at each end, they may also be supported at other points by dwarf walls.

By the very nature of this flooring system, cavities are created in three main areas: Between the bottom surface of the concrete block and the top of the wall that supports the beams.

Where beams are laid in an offset formation resting on a shared wall and where areas of beams are arranged at 900 to each other to form "T" junctions.

These cavities need to be filled prior to the final floor surface being applied. This is usually achieved with the use of shuttering boards which are either secured in place from beneath the floor or individually cut to seal the irregular shaped holes from above. Cavities between the bottom of the infill blocks and the top of the supporting walls tend to be filled with bricks or cut blocks and mortar.

Some of the draw backs to these traditional methods of shuttering are as follows: Wooden boards and battens have to bought, supplied to and stored at the work site.

Carpenters need to be paid to erect complex shuttering which can be time consuming.

The coordination of tradesmen is required.

Wooden shuttering will decompose over time and therefore needs to be removed and discarded once the concrete has cured.

To overcome the above, the present invention proposes a lightweight, flat packed, modular shuttering system which can be left in place once it has been filled with concrete. It consists of three elements all of which are die-cut from flat sheet and will be made up on site prior to use.

The three elements consist of: A box which can be filled with concrete or expandable foam and that has openings on four of its six sides which will allow the fill material to come into contact with its surroundings. A pleated I folded sheet which self expands to fit various size apertures and a step formation, creating a ledge on the end of a beam to be used in conjunction with the pleated I folded sheet.

The main advantage of this system is its ease of deployment.

It can be deployed by one person in a fraction of the time it would take to shutter cavities by traditional methods.

The elements are lightweight, die-cut from sheet of material, preferably 800 micron polypropylene allowing it to be sent flat packed by post, reducing on site storage requirements.

Polypropylene is cheaper than wood.

There will be no waste material to dispose of on site.

These elements will not decompose and so can be left in place after construction.

An example of the invention will now be described by referring to the accompanying drawings: Figure Ia Shows a series of concrete beams (1) with concrete infihl blocks (2) resting on a supporting wall (3) forming a cavity (4) between the bottom of the block and the top of the supporting wall.

Figure lb Shows a series of concrete beams (I) laid out in an offset formation complete with concrete infill blocks (2) resting on a supporting wall (3) forming a cavity (4) between the blocks.

Figure ic Shows a series of concrete beams (1) complete with concrete infill blocks (2) arranged at 900 to each other to form "T" junctions, resting on a supporting waIl (3) and forming a cavity (4) between the blocks.

Figure 2 Shows the fist die cut element of this system. Once erected it forms a box which has openings on four sides. Although a shorter version of this box element would be used when the beams are laid closer together and the infill blocks turned through 90 the same features would be kept. After being inserted between the beams (1) it would be filled with concrete from above and sealed in place with a block.

During the erection of the box feature (5) would be removed, providing the openings which would allow the fill material to come into contact with its surroundings. Once erected they will be reinserted through the slots (7) to form bracing struts. Feature (6) shows the locking tabs which hold the box together. Feature (8) form extensions to the length of the box and wilt be shaped to match the profile of the concrete beam (1). Its function is to seal off any gaps that would allow the fill material to escape. Feature (9) represents a series of self closing flaps which would allow the box to be filled with expanding foam via a pipe should access from above be denied by a previously laid floor.

Figure 3 Show a series of assembly drawings of the shorter box element described above.

Figure 4 Shows the installation of the box element between the beams (1), the bracing struts (5), extension flaps (8) and the self closing flaps (9) Figure 5 Shows the second die cut element of this system. It is a simple flat sheet which has a series of equally spaced running cuts or creases (10) running parallel to each other extending across the width of the sheet. This element is erected by folding it along the length of the first crease in one direction and then in the opposite direction at the next crease forming a series of pleats or V shaped channels. These channels give this shutter its strength allowing a considerable downward force to be applied to it before failure occurs.

To install this shutter, it is simply compressed and dropped into the cavity resting upon the ledges that support the infihl blocks. It springs open sealing off the cavity leaving it ready to be filled with concrete. Adding notches (11) to the design allows for a tighter fit of the shutter to the profile of the concrete beam (1).

Figure 6 Shows a series of drawings depicting the installation of this shutter and subsequent modification to accommodate any obstacles that it may encounter. As it self expands it will automatically fill a variety of cavity widths.

Figure 7 Shows the third die cut element of this system. Again made from fiat sheet it is erected to provide a supporting ledge across the end section of a concrete beam (1) allowing the previously described second element (figure 5) to be used. It is held in place by the weight of a concrete block.

Feature (12) shows two flaps which are folded perpendicular to the rest of the sheet. The barbed lugs (13) locate and lock into the slots (14) as the element is folded up adding strength to the design. As the assembly progresses, the flaps (15) interlock with each other providing multiple layers of material ensuring that a good grip is achieved between the block, step and ledge.

Figure 8 Shows a series of drawings depicting the assembly and installation of this step element and the previously described self expanding shutter (Figure 5).

Claims

CLAIMS: 1. A former suitable for use in a beam and block flooring system,

the former comprising a sheet of material having a net of a former formed therein, the net having a base, and two sidewalls projecting from the base which may be folded such that the sides are substantially parallel to each other and oriented substantially perpendicular to the base, the base being provided with at least one push-out piece, the sidewalls having means for receiving the push-out piece such that the push-out piece can act as a strut for helping the sidewalls to maintain an orientation substantially perpendicular to the base.
2- The former of claim 1 wherein said ends of said two sidewalls are shaped to conform substantially to a profile of a beam such that, in use, leakage of concrete or foam from the former is reduced.
3. The former of claim 1 or claim 2 wherein the strut is adapted to pass through a slit in each sidewall, and to grip each sidewall.
4. The former of any one of claims I to S wherein the net further comprises an end wall projecting from the base proximate an end of said two walls.
5. The former of claim 4 wherein said end wall further comprises at least one push-out piece.
6. The former of claim 5 wherein said push-out piece of the end wall is configured to form a strut
7. The former of claim 6 wherein an edge of a sidewall comprises at least one tab, said at least one tab being configured to engage a portion of an aperture formed in an end wall when a push-out is removed from said end wall.
8. The former of any one of claims 1 to 7 wherein at least one of said two sidewalls further includes a flap or aperture through which a former may be filled with foam.

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9. The former of claim 8 wherein the flap is a self-closing flap.
10. The former of claim 9 wherein the flap is pre-cut in said at least one of said two walls.

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11. The former of any one of claims Ito 10 wherein the sheet of material comprises a corrugated material.
12. The former of any one of claims I to 11 wherein the sheet of material comprises a tO plastics material.
13. The former of claim 12 wherein the plastics material is polypropylene.
14. A shutter system comprising a former as claimed in any one of claims 1 to 13 and a shutter board.
15. The system of claim 14 wherein the shutter board comprises a sheet of resiliently flexible material having a series of creases running substantially parallel to each other along a length of the sheet, and disposed across a width of the sheet, such that adjacent creases may be folded in opposite directions so as to form a pleated or corrugated structure.
16. The system of claim 15 wherein notches are provided at an end of alternate creases along an edge of the shutter board, an apex of each notch being coincident with alternate creases.
17. The system of any one of claims 14 to 16 wherein the shutter board is provided in the form of a substantially flat sheet having a location of a crease line indicated on the sheet.
16. The system of claim 17 wherein said indication of the location of a crease line is a score-line.
19. The system of any one of claims 14 to 18 wherein the system further comprises a ledge assembly for supporting a shutter board, the assembly having means for supporting a portion of a shutter board, and means for attachment of the assembly to a wall.
The system of claim 19 wherein the means for attachment is a grip, the grip comprising a pair of substantially parallel wings fixedly connected to the ledge and projecting therefrom, the wings having a gap therebetween corresponding substantially to a thickness of the beam.
21. The system of claim 19 or claim 20 wherein the assembly is provided with a tab portion fixedly connected to the assembly, the tab portion being suitable for sandwiching between the beam and the block.
22. A method of building a floor, the method comprising the steps of: installing a plurality of beams to overlie at least one supporting wall; installing a former as claimed in any one of claims 1 to 13 over a supporting wall between two beams such that the base is positioned along a top of the supporting wall between two beams, with the two sidewalls of the former substantially parallel to the supporting wall, and such that ends of said two sidewalls of the former substantially abut said two beams; pouring concrete into the former to substantially fill the former; overlaying the beam with precast concrete blocks; and depositing a layer of scree to form a floor.
23. A method of building a floor, the method comprising the steps of: installing a plurality of beams to overlie at least one supporting wall; installing the shutter system of any one of claims 14 to 18 over a supporting wall between two beams, such that the base of the former is positioned along a top of the supporting wall between two beams, with the two sidewalls of the former substantially parallel to the supporting wall, and such that ends of said two sidewalls of the former substantially abut said two beams; pouring concrete into the former to substantially fill the former; overlaying the beam with precast concrete blocks; installing the shutter board; and depositing a layer of scree to form a floor.

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24. The method of claim 24 wherein the method further comprises the step of installing a ledge prior to installing the shutter board.
25. A former substantially as hereinbefore described with reference to the accompanying drawings.
26. A shutter system substantially as hereinbefore described with reference to the accompanying drawings.
27. A method of building a floor substantially as hereinbefore described with reference to the accompanying drawings.