GB2285071A

GB2285071A - Metal sheet structures;permanent shuttering

Info

Publication number: GB2285071A
Application number: GB9425873A
Authority: GB
Inventors: Stewart Gallocher
Original assignee: University of Strathclyde
Current assignee: University of Strathclyde
Priority date: 1993-12-23
Filing date: 1994-12-21
Publication date: 1995-06-28
Also published as: GB9326299D0; GB9425873D0

Abstract

Metal sheet (10) is folded to form a hollow body (11) which is elongate and of constant cross-section along its length. The cross-section has a first face (11C) which defines a re-entrant profile and a second face (11A) containing the edges of the sheet (10) which defines a protrusive profile. The re-entrant and protrusive profiles are geometrically similar which enables adjacent similar sheets to be interlockingly engaged to one another, e.g. for use as permanent shuttering for a concrete wall as in Fig.2. <IMAGE>

Description

METAL STRUCTURES This invention relates to metal structures for use in the construction industry, and particularly but not exclusively to the construction of concrete walling.

Hitherto concrete walling has been produced by pouring wet concrete between shuttering which may be made of metal or wood and which has subsequently been removed. The concrete may or may not have metal reinforcement embedded within it.

It is a object of the present invention to provide new and improved metal structures for use in the construction industry and to methods of construction utilising such metal structures.

The present invention provides in one of its aspects a method of constructing a structural body which comprises assembling a plurality of elongate machine-formed metal sections with adjacent sections mutually interlockingly engaged to provide a hollow body.

The present invention provides in another of its aspects metal sheet machine-formed to define an elongate hollow body of constant cross-section, said cross-section comprising first and second faces respectively carrying geometricallysimilar re-entrant and protrusive interlocking engagement means, whereby to enable the formed sheet interlockingly to engage with adjacent similarly-formed metal sheets.

Preferably the first face on its re-entrant portion and the second face on its protrusive portion are each apertured along the length of the sheet to enable the hollow bodies of interconnected formed sheets to be interconnected for filling and bonding together with a fill material, for example concrete.

Preferably the protrusive interlocking engagement means is formed by first and second jaws extending along opposed edges of the metal sheet and, after forming, being spaced apart by a gap, the arrangement being such that the jaws are resiliently deformable to narrow the gap to thereby enable engagement with the re-entrant interlocking engagement means of an adjacent similarly formed metal sheet.

The cross-section is preferably polygonal and may be generally square or rectangular with the first and second faces mutually opposed but many other cross-sections are possible. For example the cross-section may include one or more curved faces. Of course, the first and second faces need not be mutually opposed and for example may be adjacent. Conveniently the metal sheet is sheet steel having a thickness of the order of 1 mm. Greater thicknesses are possible and desirable for increased corrosion resistance in certain circumstances.

In a still further aspect the present invention provides a structural body when formed in accordance with the aforesaid method. The structural body may be a wall or a pillar, for example. The respective hollow bodies of the structural body may be filled with concrete.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a formed metal sheet in accordance with one aspect of the present invention; Fig. 2 illustrates in plan view part of a wall utilising the formed metal sheet of Fig.l; Fig. 3 illustrates in plan view part of a wall utilising a modified form of formed metal sheet, Fig. 4 illustrates a first detail of the Fig. 1 metal sheet; and Fig. 5 illustrates in plan view a pillar utilising a modified form of formed metal sheet.

The metal sheet 10 shown in Fig. 1 is machine formed to define an elongate hollow body 11 of constant polygonal cross-section along the length, in this instance generally square. One method of achieving this is by wrapping the sheet around a mandrel of suitable shape and applying external pressure. The sheet 10 is made of steel, preferably zinc plated to provide corrosion resistance, and is about 1 mm. in thickness. The body 11 has four faces, viz llA, llB, llC and llD. Faces llA and llC are mutually opposed and carry, by virtue of the metal sheet being pressed into a profile, geometrically-similar interlocking engagement means, one being re-entrant and the other being protrusive.

In this embodiment the engagement means are profiles of the dove-tail type but it will be recognised that other forms of interlocking engagement are possible. The protrusive engagement means is formed by jaws extending along the opposed edges of the sheet 10 and which after forming are spaced apart by a gap. The sheet 10 and faces 11B, llD are resilient such that the jaws are manually moveable to narrow the gap and engage with the comparatively rigid re-entrant engagement means which is formed on the face llC.

Within the re-entrant portion of face 11C there is provided a series of apertures 13 which when two adjacent hollow bodies 11 are interlockingly engaged as shown in Fig.

2 lie in the gap formed between the jaws 12A,12B which form the protrusive engagement (see Fig. 4) so that concrete can be poured into the wall provided by the adjoining hollow bodies 11 and be keyed to the metal sheet 10 by flow through the apertured portions thereof. Fig. 4 illustrates further keying 14A,14B preferably provided on the planar faces llB,llD by embossing. Keying 14A, 14B also enhances the rigidity of the body 11.

Fig. 3 illustrates in plan view a modified polygonal cross-sectional shape in which face lIB is of substantially reduced width and adjacent faces are no longer orthogonal.

This form of hollow body is suitable for forming a corner on a wall. An alternative method of forming a corner would be to use a modified version of the Fig. 1 body 11 in which the jaws 12A, 12B are on a side of the cross-section adjacent the re-entrant engagement face.

It will be appreciated that the dove-tail engagement provided by the jaws 12A,12B on one face of the hollow body 11 is achieved by manual displacement of the jaws 12A,12B.

The metal sheet is sufficiently resilient to permit this displacement on a temporary basis.

Fig. 5 illustrates a concrete-filled column formed from four interengaged metal sections 18 each of which has three faces of which one is curved, and the other two which are mutually adjacent respectively provide the protrusion engagement and the re-entrant engagement.

By virtue of the described embodiments a formwork is provided during casting of concrete and external reinforcement is provided after curing of the concrete. The hollow wall is very easy to construct rapidly and, in use, provides shear resistance against lateral loading so that either as a hollow wall or as a composite wall (when concrete filled) it has a great many uses.

Claims

1. Metal sheet machine-formed to define an elongate hollow body of constant cross-section, said cross-section comprising first and second faces respectively carrying geometrically- similar re-entrant and protrusive interlocking engagement means, whereby to enable the formed sheet interlockingly to engage with adjacent similarly-formed metal sheets.

2. Metal sheet as claimed in Claim i, wherein the first face on its re-entrant portion and the second face on its protrusive portion are each apertured along the length of the sheet to enable the hollow bodies of interconnected formed sheets to be interconnected for filling and bonding together with a fill material, for example concrete.

3. Metal sheet as claimed in either preceding claim, wherein the protrusive interlocking engagement means is formed by first and second jaws extending along opposed edges of the metal sheet and, after forming, being spaced apart by a gap, the arrangement being such that the jaws are resiliently deformable to narrow the gap to thereby enable engagement with the re-entrant interlocking engagement means of an adjacent similarly formed metal sheet.

4. Metal sheet as claimed in any preceding claim, wherein the cross-section has at least one other face which is embossed along its length to provide inwardly protruding keys in the hollow body to facilitate bonding to a filler and to provide rigidity of the hollow body during pouring of the fill material.

5. A structural body formed from a plurality of metal sheets as claimed in any preceding claim and with adjacent sheets mutually interlockingly engaged.

6. A structural body as claimed in claim 5, wherein the hollow bodies of the metal sheets are filled with a fill material, for example concrete.

7. A method of constructing a structural body comprises assembling a plurality of metal sheets each as claimed in claim 1, and engaging the re-entrant and protrusive interlocking engagement means of adjacent sheets of the assembly.