GB2575142A

GB2575142A - Integral shuttering system

Info

Publication number: GB2575142A
Application number: GB201903405A
Authority: GB
Inventors: Kiss Paul; Grist David; Fraser Dunstan Karl
Original assignee: Abbey Pynford Holdings Ltd
Current assignee: Abbey Pynford Holdings Ltd
Priority date: 2018-06-29
Filing date: 2019-03-13
Publication date: 2020-01-01
Also published as: GB202001166D0; GB201903405D0; GB2583401A

Abstract

A shutter member 1 is formed from a single, substantially planar sheet of malleable material, and comprises at least one predefined line of weakness 5. A first portion 3 folds about the line of weakness relative to a second portion 2, such that the shutter adopts a folded configuration. The first portion may be a wall portion that is perpendicular to the second portion in the folded configuration. The upper edge of the wall portion may include a line of weakness to define a foldable edge portion 8, 10 that is L- or n-shaped in profile. The shutter may comprise a second wall portion 4 opposite the first. The shutter may comprise at least one tie 7 comprising an engagement in the form of a slot 11 in an end of the tie which receives a tab 12. The tie may extend from an edge portion of the shutter, or may be formed wholly within a portion of the shutter. The shutter may be stamped or cut from sheet metal as a single component. A shutter bridging tie may engage with an adjacent shutter member.

Description

Integral Shuttering System

The present invention relates to a shuttering system for concrete or other settable material and particularly, but not exclusively, to a shuttering system for use in forming a concrete raft or beam of a building, or for forming features on or in a concrete raft or low level beam of a building.

In the construction of domestic and commercial buildings, concrete rafts are commonly used as alternatives to traditional foundations such as strip footings or piles and ground beams. Such rafts comprise a concrete slab reinforced by steel bars, which may be supported directly on appropriately treated ground (possibly by compaction where soil type permits this) or supported by piles.

Whether the concrete raft is to be supported directly by the ground or from piles, it is first necessary to provide appropriate formwork to receive the poured concrete and define the shape of the raft. The formwork will include a substrate to support the poured concrete of the raft until it has set. If the raft is to be formed on appropriately treated ground, then the substrate will often be a levelled rough concrete working surface. Alternatively, where the raft is to be supported from piles, the substrate will normally be a temporary substrate built around the piles, such as a plywood deck supported by temporary deck support units. When the concrete has set to form the raft, the deck support units and deck are subsequently removed, to leave the raft supported by piles and to provide a void under the deck. Such a void may be particularly advantageous where ground heave may otherwise be a problem or ventilation is required for degassing, for example when building on a previous brown field site, avoiding the need to remove possibly contaminated soil.

An advantage of using a concrete raft for the base of a building is that the walls of the building may be supported by the concrete raft, avoiding the need for traditional footings and excavations. However, this in turn means there is no sub-structure brick work or block work to retain the poured concrete when the raft is being formed. Therefore, in addition to providing formwork in the form of a substrate on which to form the raft, it is also necessary to provide formwork to shutter the concrete to define the edge of the raft.

Traditionally, wooden shuttering is used to define the edge of a raft. However, wooden shuttering is relatively time consuming and expensive to erect. Furthermore, it is necessary to “strike” the shuttering to clear the shuttering from the site once the raft has set. In addition, it is also difficult with wooden shuttering to form features on or in the raft. For example, it is sometimes desirable to provide a notch (step down) along the edge of the raft to decrease the thickness of the raft at the edges.

As an alternative to wooden shuttering, metal shuttering systems have been developed, which provide a relatively inexpensive and facile means for defining the edges of a concrete raft and any additional features provided on or in the raft. For example, UK Patent Applications, Publication Nos. GB 2522886 and GB 2522887 disclose a range of shuttering systems comprising metal shutter members arranged to be interconnected to define the edges of a raft to be poured, which raft may be formed from concrete or other settable material.

Such shutter members generally comprise base portions arranged to be placed on a substrate in a substantially horizontal orientation, and one or more wall portions extending perpendicularly from the base portion, in a substantially vertical orientation. The one or more wall portions provide barriers to retain concrete or other settable material, thus defining the edges of the raft being formed. The shutter members may comprise apertures to allow reinforcing bars to pass through from one part of the raft defined by a first wall portion, to a another part of the raft defined by a second wall portion. Such apertures may also allow the passage of concrete or other settable material through the wall portions and/or base portion.

The configuration of the shutter members depends upon the particular application. A range of shutter members having different configurations for different applications are disclosed in GB 2522886. The shutter members are therefore preformed into the desired shape and configuration, and are subsequently transported to the construction site, where they are assembled to form the shuttering system. However, since the shutter members are preformed into the desired shape at the point of manufacture, space is required storage and transportation of the shutter members prior to use.

Additional components of the shuttering system may also be provided separate to the shutter members. For example, connecting plate members may be provided to connect adjacent shutter members and to keep the wall portions of adjacent shutter members correctly aligned. Additionally, brace members may be provided to brace the wall portions and base portion of the shutter members. Accordingly, assembly of the shuttering systems can be complicated and time consuming, and requires a correct number of appropriate components to be at hand when the shuttering system is being erected.

The present invention arose to provide an improved shutter member for shuttering systems used in the formation of concrete foundations.

According to the present invention, there is provided a shutter member for a shuttering system for concrete or other settable material, wherein the shutter member is formed from a single, substantially planar sheet of malleable material, and wherein the shutter member comprises at least one predefined line of weakness arranged to permit a first portion of the shutter member to fold about said predefined line of weakness relative to a second portion of the shutter member, such that the shutter member adopts a folded configuration.

The present invention provides a shutter member which is manufactured by being cut or stamped out of a single planar sheet of malleable material. References herein to features being cut or stamped out of a sheet of a material refer to any appropriate processes which may be used to form a sheet material having a desired shape and having desired features such as apertures, slots or perforations, for example, formed therein.

The one or more predefined lines of weakness allow the shutter member, formed in a planar, flat configuration, to be folded about the lines of weakness into a folded configuration for use in a shuttering system. Accordingly, the shutter members may be manufactured, stored and transported to a construction site in a flat configuration, and may subsequently be folded manually into a folded configuration on site for use within a shuttering system. A large number of shutter members can therefore be stacked, with the stack occupying minimal space. This significantly reduces the burden of providing space for storage and transportation of the shutter members.

Advantageously, component parts of the shutter member, such as ties for engaging opposing walls of the shutter member, or for engaging a wall of the shutter member with a base of the shutter member, may be formed integrally with the shutter member. Such features may then be folded about a predefined line of weakness in order to perform their function.

In some embodiments, the first portion of the shutter member sits substantially perpendicularly to the second portion when the shutter member is in the folded configuration. Said first portion may be a wall portion of the shutter member and said second portion may be a base portion of said shutter member, the wall portion being adjacent the base portion and being delimited from said first portion by said predefined line of weakness. Accordingly, the wall portion can be manually folded about said predefined line of weakness in order to place the wall portion substantially at right angles to the base portion.

In alternative embodiments, said first portion may be a first wall portion, and said second portion may be a second wall portion, the first and second wall portions being joined at said predefined line of weakness. Accordingly, the first wall portion may be folded relative to the second wall portion in order to place the first wall portion substantially at right angles to the second wall portion, or alternatively at any other predefined angle. Such an arrangement may be used to form a corner section of shuttering, for example.

In embodiments of the present invention wherein the first portion comprises a wall portion of the shutter member and the second portion comprises a base portion of the shutter member, a further predefined line of weakness may be provided in the wall portion, which predefined line of weakness extends parallel to an upper edge of the wall portion to define a foldable edge portion. When the shutter member is in the folded configuration, the foldable edge portion may be substantially L-shaped in profile. Accordingly, the foldable edge portion comprises, in use, a flat portion arranged to extend substantially parallel to and flush with the top surface of concrete or other settable material which is retained by said wall portion. The L-shaped profile of the foldable edge portion enhances the rigidity of the upper edge of the wall portion, thus restricting any folding or bending of the wall portion.

In some embodiments, the foldable edge portion may be defined by two predefined lines of weakness provided in the wall portion, which predefined lines of weakness extend parallel to the upper edge of the wall portion and to each other. When the shutter member is in the folded configuration, the foldable edge portion is thereby substantially n-shaped in profile. Accordingly, the foldable edge portion comprises a flat portion arranged to extend substantially parallel to and flush with the top surface of concrete or other settable material which is retained by said wall portion, and further comprises a distal edge arranged to extend down into the concrete or other settable material. This prevents the wall portion from peeling away from the settable material, once the settable material has set. The nshaped profile also provides enhanced rigidity of the upper edge of the wall portion.

In some embodiments, the wall portion is a first wall portion, and the shutter member further comprises a second wall portion delimited from the base portion by a predetermined line of weakness and being arranged to oppose the first wall portion when the shutter member is in the folded configuration. Accordingly, there is provided a shutter member defining an internal space between the opposing first and second wall portions, into which internal space concrete or other settable material can be poured and allowed to set.

The shutter member preferably comprises a plurality of indentations or deformations formed in the shutter member. The indentations or deformations may preferably be formed in one or more wall portions of the shutter member. The indentations or deformations provide enhanced rigidity to the shutter member in the portion in which they are formed.

The indentations or deformations may preferably be elongate, and may be oriented to strengthen the shutter member in a particular direction or plane. For example, some embodiments of the present invention may comprise a plurality of elongate indentations or deformations formed in a wall portion of the shutter member, which indentations or deformations are oriented substantially parallel to an upper edge of said wall portion when the shutter member is in the folded configuration. Further embodiments may alternatively or additionally comprises a plurality of elongate indentations or deformations formed in a wall portion of the shutter member, which indentations or deformations are oriented substantially perpendicular to an upper edge of said wall portion when the shutter member is in the folded configuration. Elongate indentations or deformations may alternatively or additionally be provided within a wall portion at any intermediate angle.

Preferably, the shutter member comprises at least one tie formed integrally with the shutter member and arranged to fold relative to a portion of the shutter member about a predefined line of weakness. The tie may be formed within a wall portion or base portion of the shutter member. The tie provides a means for fixing the shutter member in the folded configuration and thus enables the shutter member to maintain its shape when the shutter member is used to retain a settable material, even when a substantial force is exerted on portions of the shutter member by the concrete or other settable material.

The tie preferably comprises engagement means for engaging with a further portion of the shutter member, such as a base portion or an opposing wall portion. The engagement means may comprise a slot formed in an end of the tie, the slot being arranged to receive a tab provided on the respective further portion of the shutter member. Alternatively, the engagement means may comprise a tab formed at an end of the tie arranged to be received within a slot provided on the respective further portion of the shutter member, the tab being arranged to fold relative to the respective further portion or relative to the tie so as to lock the tab within the slot.

Advantageously, the ties, tabs and slots are formed within the shutter member at the point of manufacture by being cut or stamped out from the sheet material. The tabs and ties remain joined to the shutter member at a single edge, on which edge a predefined line of weakness may be provided to allow the tabs or ties to be folded in order to perform their function.

In some embodiments, the at least one tie extends from an edge of a portion of the shutter member. The at least one tie is joined to the shutter member at said edge, and a predefined line of weakness is provided at said edge to allow the at least one tie to fold relative to the portion of the shutter member about said predefined line of weakness at said edge.

The shutter member may alternatively or additionally comprise at least one tie formed wholly within a portion of the shutter member, the tie being arranged to fold outwardly from said portion. The tie may be cut out from the portion of the shutter member and remains joined to the shutter member at only one end of the tie. The tie is preferably defined by three edges cut out from the portion of the shutter member, and a predefined line of weakness. According to this arrangement, the tie can be pre-formed within the shutter member at the point of manufacture and remains joined to the shutter member at the predefined line of weakness. In the flat configuration, the tie remains within the plane of the portion of the shutter member in which it is formed. The tie can subsequently be folded outwardly from the portion of the shutter member in which it is formed such that it protrudes outwardly from said plane.

Formation of the ties wholly within a portion of the shutter member allows the ties to be provided integrally with the shutter member, whilst minimising the wastage of sheet material when manufacturing the shutter member. Furthermore, this arrangement obviates the need for ties which extend outwardly from an edge of the shutter member, reducing the area occupied by the shutter member in the flat configuration and thus improving the ease of storage. For example, adjacent stacked of flat shutter members may be placed closer together due to the lack of components extending outwardly from the edges of the shutter members.

In some embodiments of the present invention, the shutter member may comprise a first tie formed wholly within the first portion of the shutter member, and a second tie formed wholly within another portion of the shutter member, wherein the first and second ties comprise corresponding engagement means arranged to permit the first tie to engage with the second tie when the shutter member is in the folded configuration. For example, in some embodiments the first tie is formed wholly within a wall portion of the shutter member, and the second tie is formed wholly within a base portion of the shutter member. In further embodiments, the first tie may be provided in a first wall portion and the second tie may be provided in a second wall portion. Said first and second wall portions may be opposing wall portions (i.e. joined to opposing edges of a base portion), or may be adjacent wall portions (for example, in a corner shutter member having two wall portions joined at a predefined line of weakness).

The shutter member may comprise a plurality of ties formed wholly within a wall portion of the shutter member, wherein at least two of said ties are provided at different heights within said wall portion. That is, the shutter member may comprise two ties formed wholly within the same wall portion, wherein each tie is joined to the shutter member at a joined end of the tie, and wherein the joined end of a first of the ties is closer to an upper edge of the wall portion than the joined end of a second of the ties. The shutter member may comprise a plurality of ties spaced apart in a lengthwise direction of the shutter member, where the heights of the ties are staggered.

Where the shutter member comprises a tie formed wholly within a portion of the shutter member, said tie preferably has a width of 10 mm or less, and more preferably has a width of 5 mm or less. Accordingly, when the tie is folded out from the portion of the shutter member in which it is formed, the resulting aperture formed in the respective portion of the shutter member is sufficiently narrow such that concrete or other settable material does not flow through the aperture. For example, where the tie is formed wholly within a wall portion of the shutter member, concrete or other settable material being retained by said wall portion does not pass through the aperture.

Preferably, the predefined line of weakness of the present invention comprises one or more perforations formed in the substantially planar sheet of material. The perforations may preferably account for over 50 % of the length of the line of weakness.

The shutter member may alternatively or additionally comprise at least one predefined line of weakness comprising a linear section of thinned material. That is to say, the line of weakness comprises a linear section of the sheet material having a thickness less than the thickness of main body of the sheet material from which the shutter member is formed.

The shutter member is preferably stamped or cut from sheet metal as a single component. Accordingly, all the components necessary for the formation of a shuttering system are provided as a unitary shutter member.

The substantially planar sheet of malleable material preferably has a thickness of 1.2 mm or less. Since the shutter member of the present invention need not form a structural component in the structure it is used to form, a relatively thin sheet material may be used. This has the advantage that the amount of material, for example steel, used to manufacture the shutter members is reduced, thus reducing the cost of manufacture. Where necessary, the rigidity of the shutter member is enhanced by incorporation of strengthening blisters and/or foldable edge portions, as described above. The provision of ties formed integrally with the shutter member allow the structure of the shutter member to be maintained when being used to retain concrete or other settable material.

The shutter member may comprise apertures formed in at least one of the first portion or the second portion. Such apertures may be used to allow reinforcing bars to pass through walls of the shutter member, and/or to allow concrete or other settable material to flow through the base and/or walls of the shutter member. Furthermore, apertures may be provided to allow the insertion of separate ties through a wall of the shutter member, which may be required in order to anchor together separate blocks of concrete or other settable material formed on either side of said wall, as disclosed in GB 2522887, for example.

The shutter member preferably comprises connecting portions arranged to engage with corresponding connecting portions of a further shutter member. The connecting portions are preferably formed integrally with the shutter member. Accordingly, adjacent shutter members may be connected together to form a shuttering system, without the need for any additional separate components. Ease of assembly of the shuttering system is thereby improved, and the need to have a correct number of appropriate components to hand when assembling the shuttering system is obviated. The connecting portions are preferably formed wholly within a portion of the shutter member, such that no part of the connecting portions protrudes outwardly from an edge of the shutter member.

The connecting portions may comprise a bridging tie formed wholly within a portion of the shutter member at a first end of the shutter member in a lengthwise direction, the bridging tie being arranged, in use, to extend between adjacent shutter members. A slot may be provided at a second end of the shutter member in a lengthwise direction and the bridging tie may comprise a tab at a free end of the bridging tie, which tab is foldable relative to the bridging tie. The bridging tie is arranged to fold out from the portion of the shutter member in which it is formed to bring the tab into engagement with a slot provided at the second end of an identical adjacent shutter member so as to connect the two shutter members.

The shutter member of the present invention is preferably an elongate member arranged to adjoin identical shutter members at both ends in a lengthwise direction.

According to the present invention, there is also provided a shuttering system comprising a plurality of identical shutter members, wherein the identical shutter members are arranged to be stacked in a flat configuration such that a detail on one shutter member is aligned with and/or accommodated within an equivalent detail of an adjacent shutter member in the stack. For example, any ties formed integrally with a first shutter member are preferably arranged to be aligned with corresponding ties of a second shutter member stacked above or beneath the first shutter member. Similarly, any strengthening blisters formed within the first shutter member are preferably arranged to be aligned with corresponding blisters of the second identical shutter member. Furthermore, where the blisters comprise indentations formed in the shutter member, the protruding portion of each blister formed on an upper side of the first shutter member is at least partially accommodated within a recessed portion of a corresponding blister formed on a lower side of the second shutter member stacked atop the first shutter member.

Each shutter member is preferably substantially planar when in the flat configuration, except for any details formed in the shutter member which are arranged to permanently protrude out of the plane of the shutter member, for example, strengthening blisters. That is to say, all portions of the shutter member which are in part defined by a line of weakness are preferably arranged to lie within the plane of the shutter member when in the flat configuration.

When a plurality of the shutter members are stacked, the total thickness of the stack is therefore less than or equal to the thickness of the sheet material, plus the maximum thickness of any permanently protruding portions, multiplied by the total number of shutter members within the stack.

Non-limiting embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a plan view of a shutter member in accordance with a first embodiment of the present invention, shown in a flat configuration;

Figure 2 is a perspective view of a portion of the shutter member of Figure 1, shown in a folded configuration;

Figure 3 is a perspective view of a portion of a shuttering system comprising two shutter members according to the first embodiment;

Figure 4 is a cross-section through the shuttering system of Figure 3, shown mounted to a concrete raft and with concrete poured into the shuttering system;

Figure 5 is a plan view of a shutter member in accordance with a second embodiment of the present invention, shown in a flat configuration;

Figure 6 is a perspective view of a portion of the shutter member of Figure 5, shown in a folded configuration;

Figure 7 is a cross-section through a shuttering system formed using shutter members according to the second embodiment, shown mounted to a concrete raft and with concrete poured into the shuttering system;

Figure 8 is a plan view of a shutter member in accordance with a third embodiment of the present invention, shown in a flat configuration;

Figure 9 is a perspective view of the shutter member of Figure 8, shown in a folded configuration;

Figure 10 is a cross-section through a shuttering system formed using shutter members according to the third embodiment, the shuttering system being shown mounted on a substrate and supporting a concrete raft;

Figure 11 is a plan view of a shutter member in accordance with a fourth embodiment of the present invention, shown in a flat configuration;

Figure 12 is a perspective view of the shutter member of Figure 11, shown in a folded configuration;

Figure 13 is a cross-section through the shutter member of Figure 11; and

Figure 14 is a cross-section through a shuttering system formed using shutter members according to the fourth embodiment, the shuttering system being shown mounted on a substrate and supporting a concrete raft; and

Figure 15 is a perspective view of a shuttering system according to a further embodiment of the present invention.

Shutter members according to the present invention can be used in the assembly of a range of shuttering systems to provide formwork for the formation of various structures formed from concrete or other settable material. Embodiments of the present invention are particularly suitable for defining the edges of a concrete raft and/or to define additional concrete structures formed on a concrete raft, such as an upstand for supporting a wall or column of the building or other structure under construction.

It will be appreciated that embodiments of the present invention may be used to provide shutter members of a variety of types for the formation of different structures, such as any of the shutter members disclosed in GB 2522886. Furthermore, whilst the following embodiments are described with reference to the formation of concrete structures, the present invention may equally be used in the formation of structures from other settable materials, and thus the term ‘concrete’ is to be construed as referring to concrete or other settable material.

With reference to Figures 1 to 4, there is shown a shutter member, indicated generally as 1, according to a first embodiment of the present invention, suitable for forming an upstand.

Figure 1 shows the shutter member 1 in a flat configuration. The shutter member 1 is formed from a single, substantially planar sheet of malleable material. Any appropriate material which is suitable for use in shuttering systems for concrete or other settable materials may be used. Preferably, the shutter member is formed from metal, most preferably from steel. Shutter members according to the present invention need not form structural components in the structure formed by the shuttering system, and as such the shutter members may be formed from relatively inexpensive galvanised mild steel or similar.

The shutter member 1 is an elongate unit having a longitudinal direction L and a transverse direction T.

The shutter member 1 comprises a base portion 2, a first wall portion 3 and a second wall portion 4. Each of the first and second wall portions 3, 4 are delimited from the base portion 2 by a predefined line of weakness 5, 6. The predefined lines of weakness 5, 6 permit the first and second wall portions 3, 4 to fold about the predefined lines of weakness 5, 6, such that the shutter member 1 adopts a folded configuration.

In the illustrated embodiment, the predefined lines of weakness 5, 6 each comprise a linear array of perforations formed in the sheet material. This allows the shutter member 1 to be folded about the lines of weakness 5, 6 into a folded configuration. This operation can be carried out manually by a user when assembling a shutter member 1, for example when on site during construction.

In order to permit the shutter member 1 to be folded manually, the perforations, in the illustrated embodiment, account for approximately 85 % of the line of weakness 5, 6.

In alternative embodiments, the perforations may account for a greater or smaller proportion of the line of weakness.

Alternative embodiments of the present invention may comprise lines of weakness formed by alternative means. For example, some embodiments may comprise a linear section of thinned material, wherein the thickness of the material within the linear section is substantially thinner than the thickness of the rest of the sheet material, thereby providing a line of weakness about which the shutter member can be folded.

The first wall portion 3 has a dimension in the transverse direction which is substantially equal to that of the second wall portion 4. Thus, in the folded configuration, the first wall portion 3 and the second wall portion 4 define opposing walls of the shutter member 1 having substantially equal heights.

Referring again to Figure 1, the shutter member 1 comprises a plurality of ties 7 provided on the first wall portion 3. The ties 7 are formed integrally with the shutter member 1 from the same planar sheet of malleable material. The ties 7 extend outwardly from the first wall portion 3 in the transverse direction, from a line defining a longitudinal edge 8 of the first wall portion, which longitudinal edge 8 becomes an upper edge of the first wall portion 3 when the shutter member is in the folded configuration (as will be described in greater detail with reference to Figure 2).

Each tie 7 is delimited from the first wall portion 3 by a line of weakness 9 which is aligned in the axis of the longitudinal edge 8 of the first wall portion 3. In the illustrated embodiment, each line of weakness 9 comprises a single perforation, however the lines of weakness may be formed by any appropriate means as described above. The predefined lines of weakness 9 permit the ties 7 to fold relative to the first wall portion 3.

Each of the ties 7 comprises engagement means for engaging with corresponding engagement means provided on a longitudinal edge 10 of the second wall portion 4. In the embodiment illustrated in Figure 1, each of the ties 7 comprises a slot 11 formed in a distal end of the tie 7. A plurality of tabs 12 are provided along the longitudinal edge 10 of the second wall portion 4, which longitudinal edge 10 defines an upper edge of the second wall portion 4 when the shutter member 1 is in the folded configuration. The tabs 12 are shaped and sized to be received within a corresponding slot 11 provided on a corresponding tie 7 on the first wall portion 3. Each of the tabs 12 is delimited from the second wall portion 4 by a predefined line of weakness 13, which is aligned in the axis of the longitudinal edge 10 of the second wall portion 4. In the illustrated embodiment, each line of weakness 13 comprises a perforation formed parallel to the longitudinal edge 10 of the second wall portion 4.

Each of the first and second wall portions 3, 4 comprises a plurality of foldable edge portions 14, 15, which are defined by lines of weakness 16, 17 extending parallel to a respective longitudinal edge 8, 10 of the first or second wall portion 3, 4. Accordingly, the foldable edge portions 14, 15 can be folded about the respective lines of weakness 16, 17 in order to permit the foldable edge portions 14, 15 to be folded relative to the respective first or second wall portion 3, 4 in which the foldable edge portions 14, 15 are formed.

Each of the first and second wall portions 3, 4 comprises a connecting portion 18 provided towards each end of the respective wall portion 3, 4 in a longitudinal direction of the shutter member 1. The connecting portions 18 allow the shutter member 1 to be connected to an identical adjacent shutter member or to an end cap, as will be described in greater detail below. The connecting portions 18 are formed integrally with the respective wall portion 3, 4 in which they are formed and are provided wholly within the respective wall portion 3, 4. That is to say, no part of the connecting portion 18 protrudes outwardly from an edge of the shutter member 1.

Each of the connecting portions 18 is defined by a U-shaped aperture 19, which aperture 19 is stamped or cut out of the sheet material. Each connecting portion 18 is further defined by a line of weakness 20, such that the connecting portion 18 is able to fold relative to the respective wall portion 3, 4 in which it is formed. The illustrated embodiment comprises a squared-U-shaped aperture 19, however alternative embodiments may comprise an arcuate aperture defining one or more of the connecting portions.

In order to allow the shutter member 1 to be folded from a flat configuration into a folded configuration, the shutter member 1 is formed of a relatively thin sheet material. In particular, preferred embodiments of the present invention are formed from sheet metal having a thickness of less 1.2 mm. Since the shutter member of the present invention need not form a structural component of the structure formed by the shuttering system of which the shutter member is a component, it is possible to use such a thin sheet metal for the formation of a shutter member.

Where a relatively thin sheet metal is used, it may be desirable to enhance the rigidity of the material. A plurality of ‘blisters’ 21 is therefore provided in each of the first and second wall portions 3, 4. Each ‘blister’ 21 comprises an elongate indentation formed within the respective wall portion 3, 4. The elongate blisters 21 may extend in a transverse direction, a longitudinal direction or some intermediate direction of the shutter member 1. A combination of transversely-extending and longitudinally-extending elongate blisters 21 may be provided as illustrated in Figure 1. The blisters 21 act to strengthen the respective wall portion 3, 4 in which they are formed, thus enhancing the rigidity of the shutter member 1 as a whole. Blisters of other shapes may alternatively or additionally be provided.

A plurality of apertures 22 are provided in the base portion 2. These apertures 22 allow concrete poured into the shutter member 1 to adhere to a substrate upon which the shutter member 1 is placed, such as a concrete raft, as described in greater detail below.

Referring now to Figure 2, the shutter member 1 of Figure 1 is shown in a folded configuration. Each of the first and second wall portions 3, 4 is folded relative to the base portion 2 such that the first and second wall portions 3, 4 are substantially perpendicular to the base portion 2 and substantially parallel to each other. The first and second wall portions 3, 4 therefore define opposing walls of the folded shutter member 1.

The ties 7 are folded substantially perpendicularly to the first wall portion 3 and the tabs 12 of the second wall portion 4 are received within the slots 11 at the distal ends of the ties 7, so as to engage the ties 7 with the second wall portion 4. In order to more securely engage the tabs 12 with the ties 7, each of the tabs 12 is folded substantially perpendicularly to the second wall portion 4, when received within the respective slots 11.

Accordingly, the ties 7 connect the first wall portion 3 to the second wall portion 4 when the shutter member 1 is in the folded configuration. In use, when concrete is poured into the shutter member 1, the walls 3, 4 of the shutter member 1 are thereby held in position relative to each other when subjected to the force exerted by the concrete during setting of the concrete within the shutter member 1.

The foldable edge portions 14, 15 provided on both the first and second wall portions 3, 4 are folded substantially perpendicularly to the respective wall portion 3, 4, such that each foldable edge portion 14, 15 lies in a plane substantially parallel to the plane of the base portion 2, and, accordingly, in a plane substantially parallel and flush to the top surface of a settable material contained by the shutter member 1 when in use. The upper edge 8, 10 of each of the first and second wall portions 3, 4 therefore has an inverted L-shaped profile. This L-shaped profile also provides enhanced rigidity to the shutter member 1 when in the folded configuration.

Figure 3A shows a shuttering system 23 comprising two identical shutter members 1,1a aligned end-on-end. The shutter members 1,1a are connected via the connecting portions 18, 18a provided at each of the ends of the first and second wall portions 3, 3a, 4, 4a in a longitudinal direction of the shutter members 1,1a. Whilst two connected shutter members are shown, a shuttering system of any desired length can be readily formed by assembling an appropriate number of shutter members together.

The connecting portion 18 on the first wall portion 3 of a first shutter member 1 is inserted through an aperture 19a on the first wall portion 3a of the second shutter member 1a. Likewise, the connecting portion 18a on the first wall portion 3a of the second shutter member 1a is inserted through an aperture 19 on the first wall portion 3 of the first shutter member 1. The respective first wall portions of the adjacent first and second shutter members 1, 1a are thereby interlocked. The respective second wall portions 4, 4a are connected in the same manner.

The connecting portions 18, 18a can also be used to connect an end cap 24 to a terminal end 23a of the shuttering system 23 once assembled. The end cap 24 comprises a plate 25 having two wings 26 on opposing sides of the plate 25, which wings 26 extend substantially perpendicularly to the plate 25. The end cap 24 may be pre-formed into the desired shape, or alternatively may be provided with predefined lines of weakness at the junction 27 between the plate 25 and each wing 26, allowing the end cap 24 to be manually folded into the desired shape.

Each wing 26 comprises a slot 28 arranged to receive a connecting portion 18a of the terminal shutter member 1a. In order to connect the end cap 24 to the terminal shutter member 1a, connecting portions 18a provided on respective first and second wall portions 3a, 4a of the terminal shutter member 1a are inserted through the slots 28 provided on the wings 26 of the end cap 24.

When a shuttering system is assembled by connecting the desired number of shutter members together and fitting end caps are to each of the terminal ends, and enclosed space is defined by the opposing walls of the shutter members and the end caps. Concrete can be poured into the enclosed space, whereupon the opposing walls are prevented from moving apart by the ties connecting each first wall portion of a respective second wall portion of each shutter member.

As shown in Figure 4, and as mentioned above, the shutter member 1 of the first embodiment can thus be used to construct an upstand 29 on top of a concrete foundation raft 30. The upstand 29 may be required as a base to support a wall, for example a brick wall 31 as shown in Figure 4 or alternatively a stud wall or similar. In order to provide an upstand 29 of the desired length, an appropriate number of shutter members 1 are aligned and connected in order to provide a shuttering system 23 as described above with reference to Figure 3. Referring again to Figure 4, each shutter member 1 is fastened to the concrete raft 27 by appropriate fastenings 32 extending through the base 2 of the shutter member 1. Each shutter member 1 is placed into the folded configuration by engaging the ties 7 of the first wall portion 3 with the tabs 12 of the second wall portion 4 through the slots 11 of the ties 7, as described above.

The open ends of the terminal shutter members are fitted with end caps 24 (not shown). Each of the walls of the shutter member 1 (defined by the first and second wall portions 3, 4) and the terminal end caps 24 define an enclosed area of the assembled shuttering system 23 into which concrete can be poured and retained. To form the upstand 29, concrete is poured into the enclosed area of the shuttering system 23 and allowed to set.

The shutter members 1 may alternatively be fastened to steel reinforcement of the raft (such as reinforcing bars) prior to the formation of the raft. The upstand may therefore be formed at the same time as the raft by pouring the concrete or other settable material into the assembled shuttering system at the same time as pouring the concrete or other settable material into the formwork provided to define the raft. Once poured, the top surface of the concrete or other settable material forming the raft may envelop the base portion of the shutter members forming the shuttering system of the upstand.

Where the shutter members are fastened to steel reinforcement of the raft, a plurality of spacers may be provided between each shutter member and the steel reinforcement, the shutter member being fastened to the steel reinforcement via the spacers. The spacers may comprise elongate members arranged to extend across a bottom surface of the base portion of each shutter member between the first and second wall portions. The spacers are spaced apart from each other along the length of each shutter member, such that gaps are formed between the shutter members, which gaps are filled with concrete when poured, permitting the raft to extend between the reinforcing bars and the upstand. This may optionally also permit the upstand and the raft to be formed of the same continuous mass of concrete, without any points of weakness being formed in the junction between the upstand and the raft.

With reference to Figures 5 and 6, there is shown a shutter member 33 in accordance with a second embodiment the present invention. The shutter member 33 has a similar configuration to the shutter member 1 of the first embodiment. The shutter member 33 has a base portion 34, a first wall portion 35 and a second wall portion 36. The first and second wall portions 35, 36 are delimited from the base portion 34 by predefined lines of weakness 37, 38, which, in the illustrated embodiment, comprise linear arrays of perforations. However, the lines of weakness 37, 38 may have an appropriate form as described above.

The first wall portion 35 has a dimension in the transverse direction which is substantially equal to that of the second wall portion 36. Thus, in the folded configuration, the first wall portion 35 and the second wall portion 36 define walls of the shutter member 33 having substantially equal heights.

The shutter member 33 of the second embodiment differs from the shutter member 1 of the first embodiment in comprising a plurality of ties 39 formed wholly within the first wall portion 35 of the shutter member 33. That is to say, no part of the ties 39 protrudes outwardly from any edge of the first wall portion 35 when the shutter member 33 is in the flat configuration as shown in Figure 5. The ties 39 are cut out from the first wall portion 35 and remain joined to the first wall portion 35 at only one end of the tie 39. In the illustrated embodiment, each tie 39 is joined to the first wall portion 35 at an end 40 which is nearest to a longitudinal edge 41 of the first wall portion 35. Each tie 39 is defined by three edges 39a, 39b, 39c cut out from the first wall portion 35, and a predefined line of weakness 42 provided at the joined end 40 of the tie 39. Accordingly, each tie 39 is foldable relative to the first wall portion 35 about the predefined line of weakness 42, such that each tie 39 is capable of folding outwardly from the first wall portion 35 so as to protrude out of the plane of the first wall portion 35, whilst remaining connected to the first wall portion 35 at its joined end 40.

Each tie 39 comprises a tab 43 provided at the free end 44 of the tie 39, each tab 43 being defined by a predefined line of weakness 45 extending across the width of the tie 39. Each tab 43 is therefore foldable relative to its respective tie 39.

A plurality of slots 46 are provided within the second wall portion 36, which slots 46 are aligned with corresponding ties 39 on the first wall portion 35 in the longitudinal direction L of the shutter member 33. Each slot 46 is sized and shaped to receive a tab 43 of a corresponding tie 39.

The corresponding tabs 39 and slots 46 provide cooperating engagement means for engaging the ties 39 with the second wall portion 36 of the shutter member 33 when in a folded configuration, as described in greater detail below. It will be appreciated that alternative embodiments of the present invention may equally comprise tabs provided within the first wall portion arranged to be received within corresponding slots provided within the free end of each of the ties 39. It will also be appreciated that alternative engagement means for engaging the ties 39 with the second wall portion 46 may be provided.

Each of the first and second wall portions 35, 36 comprises a foldable edge portion 47 defined by a predefined line of weakness 48 extending parallel to respective longitudinal edges 41, 49 of the first and second wall portion 35, 36. The foldable edge portions 47 can be folded relative to the respective first or second wall portion 35, 36 so as to provide an inverted L-shaped edge profile as described above in relation to the first embodiment.

The shutter member 33 further comprises blisters 50 and connecting portions 51 identical to those described above in relation to the first embodiment.

Figure 6 illustrates the shutter member 33 of the second embodiment in a folded configuration (blisters 50 not shown). The ties 39 are folded outwardly from the first wall portion 35 and extend into an internal space defined by the opposing first and second wall portions 35, 36. The first and second wall portions 35, 36 define first and second walls of the shutter member in use. The ties 39 engage with the second wall portion 36 via the cooperating tabs 43 and slots 46, the tabs 43 being folded relative to the ties once received within the slots 46 in order to securely engage the ties 39 with the second wall portion 36. Accordingly, the ties 39 prevent the opposing walls of the shutter member 33 from moving apart under the force exerted by concrete poured into the internal space.

An advantage of the arrangement of the second embodiment over the first embodiment is that the ties 39 are formed wholly within the first wall portion 35 of the shutter member 33, thus minimising wastage of sheet material when the shutter member 33 is cut or stamped out from the unitary sheet material. Furthermore, the provision of ties 39 formed wholly within the first wall portion 35 minimises the number of elements protruding outwardly from the edges of the shutter member 33 when in the flat configuration, thus enhancing the ease of storage and transport of a plurality of stacked shutter members, even when each shutter member is in a flat planar configuration.

As can be seen from Figure 6, when the ties 39 are folded outwardly from the first wall portion 35, an aperture 39a is formed within the first wall portion 35. In order to prevent concrete from leaking out of the shutter member 33 before it has set, the width of the ties 39 is preferably 10 mm or less, and more preferably 5 mm or less.

Figure 7 illustrates the use of the shutter member 33 of the second embodiment to form an upstand 52 on a concrete raft 53 in substantially the same manner as previously described for the first embodiment. Each shutter member 33 of an assembled shuttering system is fastened to the concrete raft 53 by appropriate fastenings 54 extending through the base portion 34 of the shutter member 33. Each shutter member 33 is placed into the folded configuration by engaging the tabs 43 of each of the ties 39 with the slots 46 provided in the second wall portion 36. Each tab 43 is folded relative to its tie 39 so as to securely engage each tie 39 with the second wall portion 36. Once the shuttering system has been terminated by appropriate end caps (not shown), concrete is poured into the internal space to form the upstand 52, which can be used to support a wall 55 of the structure being built.

As described above with reference to Figure 4, the shutter members may alternatively be fastened to steel reinforcement (such as reinforcing bars) of the raft prior to formation of the raft, allowing the upstand and the raft to be formed simultaneously.

Whilst the present invention has been thus far described by reference to first and second embodiments of the shutter member suitable for forming an upstand, it will be appreciated that further embodiments of the shutter member according to the present invention may be configured in order to render the shutter member suitable for a variety of different types of shuttering systems.

Referring now to Figures 8 to 10, there is shown a shutter member, indicated generally as 56, according to a third embodiment of the present invention. Figure 8 shows the shutter member 56 in a flat configuration. The shutter member 56 comprises a base portion 57, a first wall portion 58 and a second wall portion 59. The first and second wall portions 58, 59 are delimited from the base portion 57 by respective predefined lines of weakness 60, 61. Accordingly, each of the first and second wall portions 58, 59 are foldable relative to the base portion 57.

The first wall portion 58 has a dimension in the transverse direction which is larger than that of the second wall portion 59. Thus, in the folded configuration, the first wall portion 35 defines a wall of the shutter member 56 having a height greater than the height of a wall of the shutter member 56 defined by the second wall portion 59.

The shutter member 56 comprises a tie 62 formed integrally with the first wall portion 58. The tie 62 is formed wholly within the first wall portion 58, with no part of the tie 62 projecting outwardly from any edge of the first wall portion 58 when the shutter member 56 is in the flat configuration, as shown in Figure 8. The tie 62 is cut out from the first wall portion 58 and remains joined to first wall portion 58 at only one end 63 of the tie 62, which end 63 is proximate a longitudinal edge 64 of the first wall portion 58. The tie 62 is defined by three edges 62a, 62b, 62c cut out from the first wall portion 58, and a predefined line of weakness 65 provided at the joined end 63 of the tie 62. Accordingly, the tie 62 is foldable relative to the first wall portion 58 about the predefined line of weakness 65, such that the tie 62 is capable of folding outwardly from the first wall portion 58 so as to protrude out of the plane of the first wall portion 58, whilst remaining connected to the first wall portion 58 at its joined end 63.

A slot 66 is provided in a free end 67 of the tie 62, the slot 66 being arranged to receive a corresponding tab 68 provided on the second wall portion 59. The slot 66 and corresponding tab 68 provide cooperating engagement means for engaging the tie 62 provided on the first wall portion 58 with the tab 68 provided on the second wall portion 59. The tie 62 and the tab 68 are arranged to cooperate in the same manner as described above in relation to the first and second embodiments.

As for the second embodiment, an advantage of the arrangement of the third embodiment is that the tie 62 is formed wholly within the first wall portion 58, thus minimising wastage of sheet material when the shutter member 56 is cut or stamped out from the unitary sheet material. Furthermore, the provision of a tie 62 formed wholly within the first wall portion 58 minimises the number of elements protruding outwardly from the edges of the shutter member 56 in the flat configuration, thus enhancing the ease of storage and transport of a plurality of stacked shutter members even when each shutter member is in a flat, planar configuration.

Whilst the embodiment illustrated in Figures 8 to 10 comprises a single tie 62, alternative embodiments may comprise a plurality of ties formed within the first wall portion 58. Where a plurality of ties are formed within the first wall portion 58, these may be provided at different heights. That is to say, the joined ends of some of the ties may be closer to the longitudinal edge 64 of the first wall portion 58 than the joined ends of other ties. Accordingly, the wall portion is supported at various heights, which may be particularly beneficial where a taller wall portion is provided. In preferred embodiments, the heights of adjacent ties are staggered in a lengthwise direction of the shutter member 56.

Each of the first and second wall portions 58, 59 comprises a foldable edge portion 70 defined by a pair of predefined lines of weakness 71, 72, which extend parallel to the longitudinal edges 64, 65 of the first and second wall portions 58, 59. The lines of weakness 71, 72 within each pair are displaced from each other in a transverse direction of the shutter member 56. Each foldable edge portion 70 can be folded relative to the respective wall portion 58, 59 about each of the predefined lines of weakness 71, 72, such that the longitudinal edge 64, 69 of each of the first and second wall portions 58, 59 adopts an n-shaped profile in cross-section when the shutter member 56 is in the folded configuration, as shown in Figures 9 and 10.

The shutter member 56 further comprises a plurality of apertures 73 provided in the first wall portion 56. The apertures 73 provide an opening through which reinforcing bars may pass.

The shutter member 56 of the third embodiment may be used in the formation of a concrete raft 74, as illustrated in Figure 10, for subsequent construction of a building.

The raft 74 rests on compacted ground 75 over which a concrete working surface 76 has been poured. To form the raft 74, a plurality of shutter members 56 are assembled to form a shuttering system 77 of a desired size. The shutter members 56 are connected by any appropriate means, for example each shutter member 56 may comprise a connecting portion for connecting to an identical adjacent shutter member, as described above with reference to the first and second embodiments. Other means for connecting adjacent shutter members may alternatively or additionally be provided.

Each shutter member 56 is secured by fasteners 78 to appropriately levelled portions of the concrete working surface 76. The concrete working surface 76 forms a substrate on which to form the raft 74, with reinforcing bars 79a and lacer bars 79b assembled over the working surface, and with the reinforcing bars 79a extending into the shuttering system 77 through the apertures 73 formed in the first wall portion 58 of one or more of the shutter members 56. When the concrete of the raft is poured, the shuttering system 77 retains the poured concrete in place until it sets to form a main body 74a and an outer edge 74b of the raft 74.

The foldable edge portion 70 of each of the first wall portion 58 and second wall portion 59 defines an upper edge of the respective wall portion. The upper edges each have a profile which is substantially n-shaped in cross-section, having a top flat portion 70a arranged so that, in use, the top flat portion 70a is substantially parallel and flush to the top surface of the concrete contained by the respective wall portion 58, 59, and having a distal edge 70b extending downward into the settable material. With this arrangement, the distal edge 70b extending down into the settable material prevents the respective wall portions

58, 59 from peeling away from the settable material, once the settable material has set.

Furthermore, the n-shaped profile of the upper edges of the wall portions 58, 59 provide further rigidity to the shutter member 56.

It will be appreciated that any of the shutter members according the present invention may be provided with foldable edge portions which, when in the folded configuration, have an n-shaped profile as described. For example, whilst the shutter members of Figures 1 to 7 comprise upper edges having an L-shaped profile when folded, these may alternatively be provided upper edges having an n-shaped profile by forming appropriate lines of weakness within the first or second wall portions of the shutter members.

An advantage of such a shuttering system 77, as illustrated in Figure 10, is that it permits brick work to be subsequently built on the outer edge of 74b of the raft 74, which outer edge 74b has sufficient depth to support the brick work while reducing the depth of the raft 74 visible externally of the finished building. It may subsequently be desirable to bring the ground level up to the top of the outer edge 74a so the raft 74 is not visible externally of the building.

As can be seen from Figure 10, a shuttering system 77 in accordance with the present invention enables a raft 74 to be constructed which may permit a wall of a building to extend down to ground level, without the need to provide traditional footings. This may thus avoid the need to make substantial excavations below the wall and incur costs, problems and time that are normally associated with this.

Referring now to Figures 11 to 14, there is shown a fourth embodiment of a shutter member, indicated generally as 80, in accordance with the present invention. The shutter member 80 of the fourth embodiment is suitable for forming a concrete raft with a single vertical edge.

The shutter member 80 is shown in Figure 11 in a flat configuration. The shutter member 80 comprises a base portion 81 and a wall portion 82, the wall portion 82 being delimited from the base portion 81 by a predefined line of weakness 83. Accordingly, the wall portion 82 is foldable relative to the base portion 81.

The first wall portion 82 comprises a plurality of wall ties 84, each wall tie 84 being integral with the wall portion 82 and being formed wholly within the wall portion 82. Each wall tie 84 is cut out from the wall portion 82 and remains joined to the wall portion 82 at only one end 85 of the wall tie 84. Each wall tie 84 is defined by three edges 84a, 84b, 84c cut out from the wall portion 82, and a predefined line of weakness 86 provided at the joined end 85 of the wall tie 84. Each wall tie 84 is thereby foldable relative to the wall portion 82 about the predefined line of weakness 86, such that each wall tie 84 is capable of folding outwardly from the wall portion 82 so as to protrude out of the plane of the wall portion 82 when in the folded configuration, whilst remaining connected to the wall portion 82 at its joined end 85.

Each wall tie 84 comprises a tab 87 at its free end 88 (the free end 88 being the end opposing the joined end 85), the tab 87 being defined by a predefined line of weakness 89 extending across the width of the tie 84. The tab 87 is foldable relative to the tie 84 about the predefined line of weakness 89.

The base portion 81 comprises a plurality of base ties 90, each base tie 90 being integral with the base portion 81 and being formed wholly within the base portion 81. Each base tie 90 is cut out from the base portion 81 and remains joined to the base portion 81 at only one end 91 of the base tie 90. Each base tie 90 is defined by three edges 90a, 90b, 90c cut out from the base portion 81, and a predefined line of weakness 92 provided at the joined end 91 of the base tie 90. Accordingly, each base tie 90 is foldable relative to the base portion 81 about the predefined line of weakness 92, such that the base tie 90 is capable of folding outwardly from the base portion 81 so as to protrude out of the plane of the base portion 81, whilst remaining connected to the base portion 81 at its joined end 91.

Each base tie 90 comprises a slot 93 provided in its free end 94 (the free end 94 being the end opposing the joined end 91). The slot 93 is sized and shaped to receive a tab 87 of a corresponding wall tie 84 to engage the wall tie 84 with the base tie 90.

The wall portion 82 comprises a foldable edge portion 94 defined by two parallel predefined lines of weakness 95, 96, each being parallel to a longitudinal edge 97 of the wall portion 82. The foldable wall portion 94 defines an upper edge of the wall portion 82 when in the folded configuration, as shown in Figure 12. When in the folded configuration, the upper edge of the shutter member has a profile which is n-shaped in cross-section, by being folded about both parallel lines of weakness 95, 96. The n-shaped profile of the upper edge is as described above in relation to the third embodiment.

Referring to Figure 12, the wall portion 82 is folded substantially perpendicularly to the base portion 81. Each wall tie 84 is engaged with a corresponding base tie 90 by insertion of the tab 87 of the wall tie 84 through the slot 93 of the base tie 90 and subsequent folding of the tab 87 about the predefined line of weakness 89. When connected, each of the wall ties 84 and the base ties 90 lie substantially within a plane which is at an oblique angle relative to the plane of the base portion 81 and the plane of the wall portion 82. In the embodiment of Figure 13, each wall tie 84 and corresponding base tie 90 lie in a plane which is at an angle a approximately 30° relative to the wall portion 82 and at an angle β approximately 60° relative to the base portion 81. However, it will be appreciated that the plane of the wall tie and base tie may lie at another angle.

Figure 14 illustrates the shutter member 80 of the fourth embodiment in use, wherein a plurality of shutter members 80 are assembled to form a shuttering system 98, which is shuttering system 98 used to form a concrete raft 99 with a single vertical edge. Each shutter member 80 is secured by fasteners 100 to appropriately levelled portions of a concrete working surface 101. The concrete working surface 101 forms a substrate on which the concrete raft 99 is formed, with reinforcing bars 102a and lacer bars 102b assembled over the working surface. When the concrete of the raft 99 is poured, the shuttering system 98 retains the poured concrete in place until it sets to form the concrete raft 99.

Concrete or other settable material poured within the shutter member is retained by the wall portion 84 of each shutter member 80. The force exerted by the concrete on the wall portion 82 and the base portion 81 bring the wall ties 84 and the base ties 90 into tension, thus holding the wall portion 81 of each shutter member 80 in a substantially vertical orientation.

It will be appreciated that the arrangement of ties described in relation to the fourth embodiment may equally be applied to shutter members having alternative configurations to the shutter member 80 illustrated in Figures 11 to 14. For example, the shutter members of any one of Figures 1 to 10 may equally be provided with mutually cooperating ties. For example, a first tie could be provided within a first wall portion of the shutter member, and a second tie could be provided within a second wall portion of the shutter member, the second wall portion opposing the first wall portion when the shutter member is in the folded configuration. The ties may then be folded out from the planes of the respective wall portions in which they are formed, into the internal space defined by the shutter member, and may then be brought into engagement by cooperating tabs and slots provided at the ends of the ties as described in detail above.

Figure 15 shows a shuttering system 110 having alternative means for connecting adjacent shutter members 111, 111a, which connecting means may be provided in any shutter member according to the present invention and may be provided as an alternative to connection portions as described above with reference to Figure 3, or in addition to such connecting portions.

In the illustrated embodiment, shutter member 111 comprises bridging ties 112 formed wholly within the shutter member 111 at a first end 113 of the shutter member 111 in a lengthwise direction. As shown, the bridging ties 112 are formed within foldable edge portions 114, 115 of first and second wall portions 116, 117, however in other embodiments, bridging ties may be alternatively or additionally be formed within other appropriate portions of the shutter member according to the particular configuration of the shutter member. For example, bridging ties may be provided in wall portions which extend vertically when the shutter member is in the folded configuration.

The bridging ties 112 are defined by three edges 112a, 112b, 112c cut out from the shutter member, and a predefined line of weakness 118, as described above. Each bridging tie 112 remains joined to the shutter member 111 at the respective predefined line of weakness 118 and is foldable about the predefined line of weakness 118, such that the bridging tie 112 can be folded out from the plane of the foldable edge portion 114, 115 in which it is formed. Each bridging tie 112 comprises a tab 119 at a free end of the bridging tie 112, each tab 119 being defined by a predefined line of weakness 120 extending across the width of the tab 119.

The bridging ties 112 are arranged to connect the first shutter member 111 to an adjacent second shutter member 111a by folding the bridging tie 112 as indicated by arrow

A, and subsequently engaging the tab 119 of the bridging tie 112 with a corresponding slot

120a provided within the second shutter member 111a, the slot 120a being provided at a second end 121a of the second shutter member 111a. Each tab 119 is received within a corresponding slot 120a, and is then folded relative to the bridging tie 112 to securely engage the bridging tie 112 within the slot 120a.

Although not shown, each of the first and second shutter members 111, 111a comprise bridging ties provided at a first end in the lengthwise direction, and corresponding slots provided at a second end in the lengthwise direction to allow the interconnection of a plurality of shutter members to form a shuttering system of a desired length.

The invention has been described above with reference to specific embodiments, given by way of example only. It will be appreciated that different arrangements of the system are possible, which fall within the scope of the appended claims.

Claims

1. A shutter member for a shuttering system for concrete or other settable material, wherein the shutter member is formed from a single, substantially planar sheet of malleable material, and wherein the shutter member comprises at least one predefined line of weakness arranged to permit a first portion of the shutter member to fold about said predefined line of weakness relative to a second portion of the shutter member, such that the shutter member adopts a folded configuration.

2. A shutter member according to claim 1, wherein the first portion sits substantially perpendicularly to the second portion when the shutter member is in the folded configuration.

3. A shutter member according to claim 1 or 2, wherein said first portion is a wall portion of the shutter member and wherein said second portion is a base portion of said shutter member, the wall portion being adjacent the base portion and being delimited from said first portion by said predefined line of weakness.

4. A shutter member according to claim 3, wherein a predefined line of weakness is provided in the wall portion, which predefined line of weakness extends parallel to an upper edge of the wall portion to define a foldable edge portion and wherein, when the shutter member is in the folded configuration, the foldable edge portion is substantially Lshaped in profile.

5. A shutter member according to claim 4, wherein the foldable edge portion is defined by two predefined lines of weakness provided in the wall portion, which predefined lines of weakness extend parallel to the upper edge of the wall portion and to each other, and wherein, when the shutter member is in the folded configuration, the foldable edge portion is substantially n-shaped in profile.

6. A shutter member according to any one of claims 3 to 5, wherein the wall portion is a first wall portion, the shutter member further comprising a second wall portion delimited from the base portion by a predetermined line of weakness and being arranged to oppose the first wall portion when the shutter member is in the folded configuration.

7. A shutter member according to any preceding claim, comprising a plurality of indentations or deformations formed within the sheet of material from which the shutter member is formed.

8. A shutter member according to any preceding claim, wherein the shutter member comprises at least one tie formed integrally with the shutter member and arranged to fold relative to a portion of the shutter member about a predefined line of weakness, the tie comprising engagement means for engaging with a further portion of the shutter member.

9. A shutter member according to claim 8, wherein the engagement means comprises a slot formed in an end of the tie, the slot being arranged to receive a tab provided on the respective further portion of the shutter member, or wherein the engagement means comprises a tab formed at an end of the tie arranged to be received within a slot provided on the respective further portion of the shutter member, the tab being arranged to fold relative to the respective further portion or relative to the tie so as to lock the tab within the slot.

10. A shutter member according to claim 8 or 9, wherein the at least one tie extends from an edge of a portion of the shutter member.

11. A shutter member according to claim 8 or 9, wherein the at least one tie is formed wholly within a portion of the shutter member, the tie being arranged to fold outwardly from said portion.

12. A shutter member according to claim 11, wherein the at least one tie is defined by three edges cut out from said portion of the shutter member, and a predefined line of weakness, wherein the at least one tie remains joined to said portion of the shutter member at said predefined line of weakness.

13. A shutter member according to claim 11 or 12, comprising a first tie formed wholly within the first portion of the shutter member, and a second tie formed wholly within another portion of the shutter member, wherein the first and second ties comprise corresponding engagement means arranged to permit the first tie to engage with the second tie when the shutter member is in the folded configuration.

14. A shutter member according to claim 13, wherein the first tie is formed wholly within a wall portion of the shutter member, and wherein the second tie is formed wholly within a base portion of the shutter member.

15. A shutter member according to any one of claims 11 to 14, wherein the at least one tie has a width of 10 mm or less.

16. A shutter member according to any preceding claim, wherein at least one predefined line of weakness comprises one or more perforations formed in the substantially planar sheet of material.

17. A shutter member according to claim 16, wherein the perforations account for over 50 % of the length of the line of weakness.

18. A shutter member according to any preceding claim, wherein at least one predefined line of weakness comprises a linear section of thinned material.

19. A shutter member according to any preceding claim, wherein the shutter member is stamped or cut from sheet metal as a single component.

20. A shutter member according to any preceding claim, wherein the substantially planar sheet of malleable material has a thickness of 1.2 mm or less.

21. A shutter member according to any preceding claim, wherein the shutter member comprises apertures formed in at least one of the first portion or the second portion.

22. A shutter member according to any preceding claim, wherein the shutter member comprises connecting portions arranged to engage with corresponding connecting portions of a further shutter member.

23. A shutter member according to claim 22, wherein the connecting portions are formed integrally with the shutter member.

24. A shutter member according to claim 23, wherein the connecting portions are formed wholly within a portion of the shutter member.

25. A shutter member according to any preceding claim, wherein the shutter member is an elongate member arranged to adjoin identical shutter members at both ends in a lengthwise direction.

26. A shutter member according to claim 25, further comprising a bridging tie at a first end in a lengthwise direction, and engagement means provided at a second end in a lengthwise direction, the bridging tie being arranged, in use, to engage with engagement means of an adjacent shutter member.

27. A shutter member according to claim 26, wherein the bridging tie comprises a foldable tab at a free end of the bridging tie, and the engagement means comprises a slot arranged to receive a tab of a bridging tie of an adjacent shutter member.

28. A shutter member according to claim 26 or 27, wherein the bridging tie is formed wholly within a portion of the shutter member and is arranged to fold out from said portion of the shutter member.

29. A shuttering system comprising a plurality of identical shutter members according to any preceding claim, wherein the identical shutter members are arranged to be stacked in a flat configuration such that a detail on one shutter member is aligned with and/or accommodated within an equivalent detail of an adjacent shutter member in the stack.