GB2522887A

GB2522887A - Shuttering system

Info

Publication number: GB2522887A
Application number: GB1402178.6A
Authority: GB
Inventors: Paul Kiss; Martin Grant Featherstone
Original assignee: Abbey Pynford Holdings Ltd
Current assignee: Abbey Pynford Holdings Ltd
Priority date: 2014-02-07
Filing date: 2014-02-07
Publication date: 2015-08-12
Anticipated expiration: 2034-02-07
Also published as: GB201402178D0; GB2522887B

Abstract

A shuttering member for supporting concrete or other settable material, and method of forming a structure, such as a raft, wherein the system has a first wall 3 with a first side 3a for retaining the material, and a second side 3b for retaining material in a cavity 7 formed by the second side, a second wall 6 and a base 5. There is at least one tie or bracing member passing through apertures (14, fig 2) in the first wall embedded in the material. The tie has first and second engagement means, the first may be protrusions 9 to engage the first wall, and the second may be protrusions 10 to engage a notch 13 in the base or second wall. The walls may have n-shaped edges 22 extending downwards to be embedded in the concrete. Openings 18 may allow concrete to pass through the first wall.

Description

Shuttering System The present invention relates to a shuttering system for supporting concrete or other settable material.

In particular, but not exclusively, the present invention relates to a shuttering system for supporting concrete or other settable material during the construction of a structure such as a foundation raft or other low level beam.

In the building industry, it is known to erect a building or other superstructure on a raft or beam which maybe supported by piles or cast directly on a suitably prepared piece of ground. This method of construction is particularly useful when building on ground that is liable to subsidence or heave, for example. The underside of the raft may be spaced above the ground by a void or compressible material. When using this method of construction, the raft or beam is typically cast in situ by pouring concrete or other settable material into formwork which defines the desired shape of the beam or raft.

The present invention aims to provide an improved shuttering system.

According to a first aspect of the present invention there is provided a shuttering system for supporting concrete or other settable material during the construction of a structure, the system comprising: a shutter member comprising: a first portion including a first wall with a first side adapted to restrain a mass of settable material during formation of the structure and a second side opposite the first side, and a second portion including a base and a second wall, wherein the second side of the first wall, the base and the second wall define a cavity for receiving settable material; and at least one separate tie comprising first and second engagement means; wherein, in use, the tie is assembled on the shutter member in a configuration in which the tie passes through an aperture in the first wall so that the tie projects from both sides of the first wall and is adapted to be embedded in settable material provided at the first side of the first wall and in the cavity; wherein the tie is adapted to be assembled on the shutter member by clipping the tie in place against the resilience of the shutter member so that the tie is locked on the shutter member when the shutter member resiles; wherein when the tie locks on the shutter member the first engagement means engages the wall at the point the tie passes through the wall, and the second engagement means engages the second portion of the shutter member; and wherein the tie is adapted to brace the first wall against the second portion when a force is applied to the first side of the first wall.

Employing the present invention, when concrete or other settable is poured against the shuttering system, the first wall of the shutter member limits the flow of the settable naterial, defining the shape of the main body of a structure such as a beam or raft (a first block of settable material). In addition, the beam or raft also includes a smaller mass of settable material at the side of the main body (a second block of settable material). This smaller mass of settable material is defined by the cavity and blockwork can be constructed on this side portion.

In the present invention, one or more ties of the shuttering system link together the two separate blocks of settable material formed by the shuttering system. As described above, the main body of a structure such as a beam or raft is formed against the first wall of the shutter member, and a blockwork support is formed within the cavity. Each tie connects the main body of the beam or raft to the blockwork support. This is advantageous as it provides extra strength to the blockwork support by transferring the load from the blockwork support into the foundation raft via the ties.

The shuttering system of the present invention can be easily assembled from separate shutter members and ties without the need for tools, decreasing the cost of assembly. A shuttering system that can be easily assembled without the use of tools also enables easy assembly on site.

Furthermore, easy assembly on site makes it possible to transport the shutter member and tie separately to the site, reducing transportation costs.

In use, the tie is assembled on the shutter member by exerting a force against the second side of the first wall of the shutter member. This causes the first wall to bend away from the second wall of the shutter member. This movement acts against the resilience of the shutter member. Therefore, when the tie is in place and the force against the second side of the first wall of the shutter member is released, the shutter member resiles to its original shape (i.e. the resilience of the shutter member allows the shutter member to resume its original shape), forcing the first wall of the shutter member against the first engagement means of the tie.

In use, the tie is assembled on the shutter member by clipping the first and second engagement means against parts of the shutter member. This clipping process can be carried out by hand and does not require the use of tools.

The first engagement means is clipped against the first wall. The first engagement means can the brace the first wall against the second portion when a force is applied to the first wall by the settable material. The second engagement means is clipped against a part of the second portion. The second engagement means prevent the ties from moving around when the settable material is being poured into and against the shuttering system.

Preferably, the first wall and the second portion are formed integrally from a sheet. However, the first wall and the second portion could be formed from two separate parts joined together, for

example, by welding.

Preferably, the shutter member comprises a pre-formed metal sheet having a length of uniform profile.

Preferably, the tie is made from a less corrosive material than the shutter member. For example, the shutter member is preferably made from mild steel, preferably mild steel that has been galvanised to resist corrosion, and the ties are preferably made from stainless steel. The shutter member is not required for structural support of the structure formed from the settable material and, therefore, can be removed without effecting the structure formed by the shuttering system.

If the structure being formed is small enough, the shutter member may be a single piece defining the perimeter of the structure. However, more preferably, the shuttering system comprises a plurality of identical shutter members arranged to be attached together end to end to form an extended shutter of a desired length having at least one tie per shutter member. In addition, the extended shutters may be joined together at the corners by specifically shaped corner portions. These corner portions will preferably have the same shaped profile as the other shutter members. The corner portions may be internal or external corners.

Preferably, the shuttering system further comprises a plurality of connecting plates to fasten adjacent shutter members together so that they may abut end to end without overlap. These connecting plates are preferably provided separately to the shutter members. Preferably, the connecting plates are used to join the adjacent shutter members together by fastening them to the first walls of neighbouring shutter members. In embodiments in which the shutter member comprises an n-shaped edge on the end of the first wall, the connecting plates may be shaped to fit under these edge portions. However, adjacent shutter means may be connected together by any other suitable means.

For example, the shutter members may comprise extensions on the first wall that are adapted to slot into slots provided on the first wall of neighbouring shutter member. Alternatively, the shutter members could be connected together by cable ties passing through holes on adjacent shutter members.

Preferably, the profile of the shutter members permits the shutter members to be nested or partly nested together prior assembling the ties on the shutter members. Having shutter members that nest together is advantageous as it enables more compact transportation of the shutter members.

Preferably, the first wall of the shutter member is taller than the second wall. This allows the hlockwork to be constructed at a height that is below the heiaht of the main structure (for example, the raft or beam), obscuring a portion of the structure from view.

Preferably, the tie is adapted to be received in the shutter member from the second side of the first wall. However, alternatively, the tie could be inserted into the shutter member from the first side of the first wall.

Preferably, the tie is substantially linear in shape and, when locked in place, the tie extends through the first wall at an angle with respect to the base. Preferably, the tie is angled at between around 30° and 60° with respect to the base. More preferably, the angle between the tie and the base is around 45, most preferably 42.

Preferably, the tie is made from a substantially rectangular piece of thin material, wherein the aperture in the first wall is wide enough to allow the narrowest dimension of the tie to pass through the aperture. However, the tie could also have other shapes. For example, the tie could be a rod with a substantially square or circular cross section. In addition, the tie may be provided with openings along its length, where these openings are adapted to receive settable material.

Preferably, the tie abuts the base. This helps the tie to provide maximum resistance to the force applied to the first surface of the first wall of the shutter member by the concrete. However, the tie does not have to contact the base in order to brace the first wall against the second portion.

Instead, the tie could contact only the second wall of the second portion.

The tie preferably abuts the base towards the second wall, i.e. the tie preferably abuts the base on the half of the base that is closest to the second wall. Such positioning of the tie is preferable as this helps to brace the first wall against the second portion. However, the tie could also be positioned closer to the first wall in alternative embodiments.

The tie preferably comprises a foot portion wherein the second engagement means is provided on the foot. In some embodiments, the foot portion may abut the base of the shutter member when the tie is assembled on the shutter member. Preferably, the foot is formed integrally with the rest of the tie. For example, the foot may be formed by bending an end of the main body of the tie.

Alternatively, the foot may be constructed from a separate piece of material that is joined on to the tie, for example, an additional piece of metal that is welded onto an end of the tie. The tie may comprise a main linear body and a foot, wherein the foot projects at 9O from the main linear body of the tie.

Preferably, the first engagement means comprises at least one protrusion on the tie, wherein the protrusions are adapted to engage the second side of the first wall. Preferably, the one or more protrusions are formed integrally with the tie. However, the one or more protrusions may also be formed by fixing screws, bolts etc onto the tie member. Alternatively, the first engagement means may comprise one or more slots adapted to engage with the side wall. The first engagement means may also be shaped so that they can fit through an opening provided in the first wall.

In some embodiments of the invention, the first engagement means of the tie could also comprise a restraint means such as a peg that can be slotted though an opening provided in the part of tie that lies just to the second side of the first wall when the tie is locked onto the shutter member. In such embodiments, the tie is first inserted through the aperture in the first wall and the second engagement means are engaged on the shutter member. Then, a force is exerted against the second side of the first wall of the shutter member to cause the first wall to bend away from the second wall of the shutter member. This movement acts against the resilience of the shutter member. The peg can then be inserted through the appropriate opening in the tie so that when the force against the second side of the first wall of the shutter member is released, the shutter member resiles to its original shape, forcing the first wall of the shutter member against the peg of the first engagement means of the tie.

The tie passes through an aperture the first wall. Preferably, when locked in place, the tie is perpendicular to the first wall. In other words, when the shutter member is viewed from above the top of the first wall, the tie extends through the aperture in the first wall so that it is substantially perpendicular to the first wall when the tie is locked in place on the shutter member. The aperture in the first wall may be an elongate slot adapted to receive a tie. Alternatively, the first wall may be provided with any shape of opening through which the tie can extend through. In embodiments in which the opening in the first wall is an elongate slot, the tie preferably has a width which maintains the tie upright in the slot.

Preferably, the first engagement means engage the first wall above and/or below the aperture in the first wall adapted to receive the tie. For example, in some embodiments, the protrusions of the first engagement means could be adapted to engage the second side of the first wall above and/or below the point at which the tie passes through the wall. For example, if the tie comprises two protrusions provided on opposite sides of the tie, wherein these protrusions are staggered along the length of the tie, these two protrusions could contact the first side of the first wall when the tie extends through an opening provided in the first wall at an angle with respect to the base.

The protrusions of the first engagement means may be barbs. The barbs are preferably triangular in shape, wherein one side of the triangular barb is adapted to abut the second side of the first wall. Alternatively, the protrusions may have any other suitable shape, for example, rectangular.

Preferably, the second engagement means comprises a protrusion adapted to engage with a notch provided on the second portion of the shutter member. The notch provided on the second portion of the shutter member may be an indent or a hole in either the base or second wall.

Preferably, the protrusion of the second engagement means is adapted to engage with a notch on the second wall. Also, in embodiments in which the tie comprises a foot portion, the protrusion of the second engagement means is preferably provided on this foot portion.

In embodiments of the invention in which the second engagement means are provided on a foot portion positioned to the side of the main linear body of the tie, the slots in the first wall are preferably not lined up with the notch provided in the second wall, i.e. each slot in the first wall preferably does not lie exactly opposite the corresponding notch on the shutter member. Instead, the slot and opening are preferably offset from each other. When the tie is being assembled on the shutter member, the tie is preferably firstly positioned through the opening so that the first engagement means engage the second side of the first wall before the foot of the tie is slid sideways to lock the second engagement means on the second wall. In these embodiments, if each slot was lined up with the corresponding opening, the protrusion of the second engagement means would have to be moved to the point at which the protrusion is positioned furthest from the first wall (i.e. the centre point) before the second engagement means could engage the opening. Depending on the distance between the first and second walls, this may involve forcing the tie to the centre point after the protrusion of the second engagement means has come into contact with the second wall. This would be a point of resistance that would slow down assembly of the tie on the shutter member.

The second engagement means may, however, be of any other form that enables it to engage the second portion of the shutter member. For example, the second engagement means may comprise a hole provided on the tie, where this hole is adapted to interact with a hook on the second portion of the shutter member.

Preferably, a top edge of at least one of the first wall and the second wall is an n-shaped edge positioned and arranged to be embedded in the settable material. The edge provided on the first wall is adapted to be embedded in the settable material provided behind the first wall. Thus, in use, the edge is surrounded by the mass of settable material resting against the a first side against during the formation of a structure such as a raft or beam. The edge provided on the second wall is adapted to be embedded in the settable material provided in the cavity. These edges help to provide extra structural stability to the shutter member once the settable material has set. In addition, as the top of the edges (i.e. the parts of the edges that lie substantially parallel to the base) are adapted to lie flush with the top of the concrete structures, the edges help to provide smooth edges for the structures formed from settable material. The n-shaped profile also acts to maintain the edges straight when the material sets.

The shutter member may also comprise one or more further openings in the first wall, wherein the one or more further openings are adapted to allow settable material to pass through the first wall.

The shutter member may also be provided with a hole in the base, where this hole is adapted to receive a fastening means such as a screw to enable the shutter member to be fastened to a surface.

In some embodiments of the invention, the shutter member is provided with a vermin plate.

This vermin plate is designed to be fitted to the shutter member and extend between the shutter member and the ground if the underside of the structure (for example, the raft! beam) is spaced above the ground. The vermin plate can then prevent vermin such as rats and mice getting into the space underneath the raft. In some embodiments, the second wall of the shutter member may be provided with an edge that is bent outwards, where the vermin plate is adapted to be fitted to this edge.

The dimensions of the shuttering system will vary. For example, the size of the shuttering system will depend on the size of the structure (for example, raft or beam) and the blockwork to be constructed. Preferably, the shutter members are longer than they are wide or tall. For examplethe shutter members typically have a length of ito 3 metres, preferably a length of 2 to 3 metres, most preferably a length of 2.5 to 3 metres, for example, the shutter members may be around 2.9 meters long.. Preferably, the shutter members are around 0.15 to 0.6 meters tall, more preferably 0.15 to 0.425 metres tall. For example, a shutter member may have a height of 0.225 metres.

In embodiments of the shuttering system, the shutter members may be of different sizes. For example, if the shutter members are being used to form the perimeter of a structure, although the depth and height of the shutter members may be the same throughout the shuttering system, the shutter members could have different lengths to allow them to form the desired shape.

In some embodiments, the shutter member may be provided with a bracket that is configured to abut the first wall and base of the shutter member. For example, a bracket may be provided in embodiments in which the height of the first wall is greater than approximately 0.225 metres. This extra bracket is preferably L-shaped. Preferably, the L-shaped bracket slots into the first wall from the first side of the first wall, wherein the bottom portion of the L-shaped bracket is adapted to be positioned through an aperture provided in the first wall when the bracket is fixed to the shutter member. In some embodiments of the invention, the L-shaped bracket is provided with engagement means adapted to interact with the first wall. These engagement means may include a protrusion with a detent adapted to interact with a slot in the first wall. The protrusion can then be inserted through the slot, wherein subsequent sideways or vertical movement of the protrusion in the slot will cause the detent on the protrusion to engage the first wall of the shutter member to lock the L-shaped bracket to said wall portion.

Preferably, the base of the shutter member further comprises an anchoring means adapted to fit the shutter member on to a surface on which the concrete is to be poured. This surface could be a layer of poured concrete and the anchoring means may be an aperture shaped and sized to receive a screw to fix the shutter member to the surface. However, the shutter member may also be provided with anchoring means for fixing the shutter member directly to a clay or soil surface.

Accordinato a second aspect of the present invention there is provided a method of constructing a structure from concrete or other settable material on a site, the method comprising: taking at least one shutter member, wherein the shutter member comprises a first portion including a first wall with a first side a second side opposite the first side, and a second portion including a base and a second wall, wherein the second side of the first wall and the second portion define a cavity; taking at least one separate tie, wherein the tie comprises a first engagement means and a second engagement means; assembling the tie on the shutter member by passing the tie through an aperture in the first wall and positioning the tie so that the tie projects from both sides of the first wall and is adapted to be embedded in settable material provided at the first side of the first wall and in the cavity; clipping the tie in place against the resilience of the shutter member so that the tie is locked on the shutter member when the shutter member resiles; wherein when the tie is locked on the shutter member the first engagement means engages the wall at the point the tie passes through the wall, and the second engagement means engages the second portion of the shutter member; anchoring the shutter member in place on the site; and pouring settable material against at least the first wall and into the cavity, wherein the tie is adapted to brace the first wall against the second portion when a force is applied to the first side of the first wall by the settable material.

This method involves assembling the tie on the shutter member by exerting a force against the second side of the first wall of the shutter member, i.e. the first wall is bent away from the second wall of the shutter member. This movement acts against the resilience of the shutter member and provides enough space to allow the tie to be clipped in place on the shutter member. Once the tie is positioned on the shutter member, the first wall of the shutter member is released, allowing the shutter member to resile to its original shape. Once the shutter member has resiled to its original shape, the shutter member is forced against at least the first engagement means of the tie.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a front perspective view of a first embodiment of a shuttering system with two ties attached; Figure 2 shows a rear perspective view of the embodiment of Figure 1; Figure 3 shows a side view of the embodiment of Figure 1; Figure 4 shows a front perspective view of the embodiment of Figure 1 with one tie removed; Figure S shows the tie of the embodiment of Figure 1; Figure 6 shows a front perspective view of a second embodiment of a shuttering system with two ties attached; Figure 7 shows a side view of the embodiment of Figure 6; Figure 8 shows a front perspective view of the embodiment of Figure 6 with one tie removed; Figure 9 shows a side view of the first embodiment where the shutter member is filled with

settable material;

Figure 10 shows a plurality of identical shutter members of the first embodiment attached together Figure 11 shows an embodiment of a connecting plate forjoining adjacent shutter members together; and Figure 12 shows a of identical shutter members of the first embodiment in a nested configuration.

Referring to Figures ito 8, two embodiments of a shuttering system 1 for supporting concrete or other settable material during the construction of a foundation raft or other low level beam, the system comprising: a shutter member 2 comprising: a first portion including a first wall 3, and a second portion 4 including a base 5 and a second wall 6, wherein the first wall 3 has a first side 3a adapted to restrain a mass of settable material during formation of a raft or beam and a second side Sb opposite the first side, wherein the second side 3b of the first wall 3 and the second portion 4 (i.e. the base 5 and the second wall 6) define a cavity 7 for receiving settable material; and at least one separate tieS comprising first and second engagement means 9, 10; wherein, in use, the tieS is assembled on the shutter member 2 in a configuration in which the tie 8 passes through an aperture 14 in the first wall 3so that the tieS projects from both sides 3a, 3b of the first wall 3 and is adapted to be embedded in settable material provided at the first side 3a of the first wall and in the cavity 7; wherein the tieS is adapted to be assembled on the shutter member 2 by clipping the tie Sin place against the resilience of the shutter member 2 so that the tie 8 is locked on the shutter member 2 when the shutter member 2 resiles; wherein when the tie 8 is locked on the shutter member 2 the first engagement means 9 engages the first wall 3 at the point the tie passes through the wall 3, and the second engagement means 10 engages the second portion 4 of the shutter member 2; and wherein the tie is adapted to brace the first wall 3 against the second portion 4 when a force is applied to the first side 3a of the first wall 3.

In the illustrated embodiments, the first wall 3 and the second portion 4 are formed integrally from a single sheet.

In use, the tie 8 is assembled on the shutter member 2 by exerting a force against the second side 3b of the first wall 3 of the shutter member 2. This causes at least part of the first wall 3 to bend away from the second wall 6 of the shutter member 2. This movement acts against the resilience of the shutter member 2. Therefore, when the tie S is in place and the force against the second side 3b of the first wall 3 of the shutter member 2 is released, the shutter member 2 resiles to its original shape, forcing the shutter member 2 against at least the first engagement means 9 of the tie 8.

In the two embodiments of Figures ito 8,the shutter member 2 preferably comprises a pre-formed metal sheet. As can be seen from Figures ito 8, the shutter member 2 has a uniform profile.

Also, in the two illustrated embodiments, the first wall 3 of the shutter member 2 is taller than the second wall 6. When blockwork such as a brick wall is constructed on top of the second portion 4 of the shutter member 2, this blockwork obscures much of the taller first wall 3 from view. Only the smaller second wall 6 is then visible from the outside of the foundation raft or beam. The shorter second wall 6 can then be concealed beneath the ground to hide the whole of the shutter member 2 from view. This is desirable as the shutter members 2 are generally considered to be less attractive than the blockwork and so it is preferred to hide them from view.

As shown in Fieures ito 9 of the illustrated embodiments, the tieS is substantially linear. In use, the tieS is assembled on the shutter member 2 so that the tie passes through the first wall 3 at an angle with respect to the bases.

The tie 8 of the embodiments shown is provided with a foot portion 11 that abuts the base 5 of the shutter member 2. In particular, in the embodiments shown, the foot 11 of the tieS abuts the bases towards the second wall 6, i.e. the tieS abuts the base 5 on the half of the base 5 that is closest to the second wall 6.

In the illustrated embodiments, the foot portion ii of the tie 8 is formed by bending the end of the tie 8 so that the foot 11 projects at substantially 9O from the tie 8.

As is most clearly shown in Figures, in the illustrated embodiments, the second engagement means 10 comprise a protrusion 12 at the end of the foot 11. This protrusion 12 is adapted to engage with a notch in the form of an opening 13 provided at the bottom of the second wall 6 of the shutter member 2.

As shown in Figures ito 9, the ties 8 of the illustrated embodiments extend through the first wall 3 of the shutter member 2. In use, the ties g are passed through slots 14 provided in the first wall 3. These slots 14 are most clearly shown in Figures 4 and 8.

The slots 14 of the two illustrated embodiments are wide enough to allow the ties 8 to pass through from the second surface 3b of the first wall 3, i.e. the ties 8 are inserted into the slots 14 from the cavity 7. However, the foot portions 11 of the ties 8 prevent the ties 8 from being inserted from the first surface 3a of the first wall Sand then into the cavity 7.

iS The slots 14 also have sufficient height to allow the ties 8 to pass through the slot. The ties 8 are provided with first engagement means 9in the form of two triangular shaped protrusions 15, 16.

When the ties 8 are inserted through the first wall 3, these protrusions 15, 16 engage the second surface 3b of the first wall above and below the slots 14. The slots 14 are, therefore, of a height that enables the protrusions is, 16 of the first engagement means to contact the first wall 3 when the ties 8 are assembled on the shutter member 2.

Also, as show most clearly in Figures, the two protrusions 15,16 of the first engagement means are staggered along the length of the tie 8. This is so that when the tie 8 is angled through the slot 14, both of the protrusions 15, 16 can contact the first surface 3a of the first wall 3.

As mentioned above, the ties 8 are passed from the cavity 7 side of the shutter member through the slots 14 in the first wall 3. As well as being able to engage with the first wall 3, the triangular protrusions 15, 16 of the illustrated embodiments are shaped to allow them to pass completely through the slot 14 during the assembly process (i.e. the protrusions are sized and shaped so that they can be positioned behind the first surface Sb of the first wall 3). Having protrusions 15, 16 on the ties 8 that can pass entirely through the slots 14 may help with the positioning of the ties 8 when these are being attached to the shutter member 2.

In addition, in the illustrated embodiments, the slots 14 in the first wall 3 of the shutter member are not lined up with the openings 13 provided in the second wall 6. Instead, the slots 14 and openings 13 are offset. The slots 14 and openings 13 are offset to allow the ties 8 to be more easily assembled S onto the shutter member 2. As shown in FigureS, for example, the protrusion 12 of the second engagement means lOis provided on a foot portion 11 that is positioned to the side of the main linear body of the tie 8. When assembling a tie 8 on the shutter member 2, the tie 8 is positioned through an opening l4so that the first engagement means 9 engage the second side 3b of the first wall 3 before the foot 11 of the tieS is slid sideways into place. If each slot 14 was lined up with the corresponding opening 13, the protrusion 12 of the second engagement means 10 would have to be moved to the point at which the protrusion 12 is positioned furthest from the first wall 3 (i.e. the centre point) before the second engagement means 10 could engage the opening 13. In the illustrated embodiments, because of the spacing between the first and second walls of the shutter member, the protrusion 12 would abut the second wall 6 at and next to the centre point. The tieS would, therefore, need to be forced to the centre point by causing the second wall to deform and bend outwards. However, in the arrangement of the embodiments of Figures ito 8, the protrusion 12 of the second engagement means snaps into the opening 13 on the shutter member 2 before the centre point, making it easier to assemble the ties 8 on the shutter member 2.

Referring to Figures ito 9, the ties comprise holes 20,21 in the main linear body of the tie 8.

In use, the concrete or other settable material can pass through these holes 20,21 to help fix the ties 8 in place. The holes 20,21 in the tieS may be of any shape, for example, they may be circular holes 20 or elongated holes 21. In the embodiments shown an elongated hole 21 is provided at the point that the tie 8 sits in the slot 14 when the tie 8 is assembled on the shutter member 2. In embodiments of the invention without protrusions 15, 16 for the first engagement means 9,the first engagement means may comprise a peg (not shown) that can be inserted through the elongated hole 21. This peg would be inserted against the resilience of the shutter member 2 and would lock the tie Son the shutter member.

As shown in the figures, the shutter member of the present invention may comprise n-shaped edges 22,23 at the end of the first and second walls 3,6. In use, these n-shaped edges 22,23 are adapted to be embedded in the settable material provided in the cavity 7 and at the first side Sa of the first wall.

More specifically, the n-shaped edge 22 of the first wall is configured to be embedded in the settable material that rests against the first side 3a of the first wall 3 of the shutter member 2 during formation of a beam! raft. Furthermore, the part 22a of the edge 22 that lies substantially parallel to the bases is adapted to lie substantially flush with the top of the beam or raft formed. Similarly, the n-shaped edge 23 of the second wall is adapted to be embedded in the settable material filling the cavity 7 formed by the shutter member 2. Again, the part 23a of the edge 23 that lies substantially parallel with the base is adapted to lie flush with the top of the settable material filling the cavity].

The shutter members 2 also comprise one or more holes 17 in the base 5. The shutter member 2 can then be fixed to a lower surface (for example, using screws) through these holes 17.

Fixing the shutter members 2 in the place stops them from moving around when the settable material is poured either side of the shutter member 2. The ties 8 maybe assembled on the shutter members 2 before the shutter member 2 is screwed in place.

In addition to the slots 14, there may be one or more further openings in the first wall 3, wherein the one or more further openings are adapted to allow settable material to pass through the first wall. For example, as clearly shown in Figure 2, the first wall may have a circular opening 18 through which settable material can pass. For example, the circular hole 18 may allow settable material poured against the first side 3a of the first wall 3 to pass through to the cavity 7. The settable material passing through the opening 18 forms a plug of settable material that connects the settable material positioned at both sides of the first wall 3 and helps to tie the blockwork support to the main structure. Embodiments of the invention comprising an additional support bracket, for example, like the embodiment of Figures 6 toS, may also comprise an opening 18 to allow the settable material to move from one side of the first wall 3 to the other.

The second embodiment of Figures 6 to 8 differs from the first embodiment shown in Figures 1 to 5 in that the second embodiment additionally comprises an L-shaped bracket 25. such an additional bracket provides additional support to the first wall 3. Preferably, the additional bracket also clips onto the shutter member. The L-shaped bracket maybe useful in embodiments of the invention in which the first wall exceeds a certain height, for example, 225 mm.

Figure 9 shows a side view of the shutter member 2 of the first embodiment in which a first block of settable material 30 fills the cavity 7, and a second block of settable material 31 is formed against the first surface 3a of the first wall 3. In Figure 9, most of the tie is not visible as it is embedded in the settable material. However, the position of the tieS is shown in dotted lines.

Fieure 10 shows a shuttering system 40 comprising a plurality of identical shutter members 2 arranged to be attached together end to end to form an extended shutter 41 of a desired length. In embodiments of the invention, the separate shutter members may have a range of different lengths, for example, each separate shutter member may have a length between ito 3 metres, for example, a length of 2.9 metres. In addition, in embodiments of the invention, the shuttering system may comprise any number of shutter members. For example, the system may comprise three, ten, twenty, thirty-five, fifty etc separate shutter members. In Figure 10, each of the three individual shutter members 2 has three slots 14 for receiving a tie. Therefore, the extended shutter is arranged so that there are three ties per shutter member 2.

A shuttering system 40 such as that shown in Figure 10 may further comprise a plurality of connecting plates 42 (see Figure 11) to fasten adjacent shutter members 2 together so that they may abut end to end without overlap. The connectine plates 38 are preferably sized and shaped to fit under the n-shaped edges 22 of the first wall 3 and are held in place by the resilience of the n-shaped edge portion 22.

A shutteririg system like that of Figure 10 may also comprise corner shuttering sections (not shown) forjoining lengths of shutter member 2 together to form the perimeter of a structure. For example, a shuttering system could comprise a total of twelve straight shutter members 2 (like those shown in the figures) and four corner shutter members. The twelve shutter members 2 could be joined together in four groups of three (as shown in Figure 10). Then, each of these groups of three shutter members 2 could be used to form the side of a square, where the sides are joined together by the four corner portions. The settable material could then be poured into the centre of the square to form a rectangular structure such as a rectangular foundation raft.

As shown in Figure 12, the profile of the shutter members 2 permits the separate shutters 2 to be nested or partly nested together to enable them to be transported prior assembling the tie(s) 8 on the shutter members 2.

Referring to all of Figures ito 12, a method of constructing a structure (such as a foundation raft or other low level beam) from concrete or other settable material on a site is provided by the present invention.

This method comprises taking a shutter member 2, wherein the shutter member 2 comprises a first portion including a first wall 3, and a second portion 4 including a base Sand a second wall 6, wherein the first wall 3 has a first side and a second side 3b opposite the first side, wherein the second side 3b of the first wall 3 and the second portion 4 (i.e the base 5 and the second wall 6) define a cavity 7; taking at least one separate tie 8, wherein the tie 8 comprises a first engagement means 9 and a second engagement means 10; assembling the tie Son the shutter member 2 by passing the tieS through an aperture 14 in the first wall 3 and positioning the tie so that the tie projects from both sides of the first wall 3 and is adapted to be embedded in settable material provided at the first side 3a of the first wall 3 and in the cavity 7; clipping the tie Sin place against the resilience of the shutter member 2so that the tieS is locked on the shutter member 2 when the shutter member 2 resiles; wherein when the tie 8 is locked on the shutter member 2, the first engagement means 9 engages the first wall 3 at the point the tie 8 passes through the first wall 3, and the second engagement means 10 engages the second portion 4 of the shutter member 2; anchoring the shutter member in place on the site; and pouring settable material against at least the first wall 3 and into the cavity 7, wherein the tieS is adapted to brace the second wall 3 against the second portion 4 when a force is applied to the first side a of the first wall 3 by the settable material poured against it.

Claims

Claims 1. A shuttering system for supporting concrete or other settable material during the construction of a structure, the system comprising: a shutter member comprising: a first portion including a first wall with a first side adapted to restrain a mass of settable material during formation of the structure and a second side opposite the first side; and a second portion including a base and a second wall, wherein the second side of the first wall, the base and the second wall define a cavity for receiving settable material; and at least one separate tie comprising first and second engagement means; wherein, in use, the tie is assembled on the shutter member in a configuration in which the tie passes through an aperture the first wall so that the tie projects from both sides of the first wall and is adapted to be embedded in settable material provided at the first side of the first wall and in the cavity; wherein the tie is adapted to be assembled on the shutter member by clipping the tie in place against the resilience of the shutter member so that the tie is locked on the shutter member when the shutter member resiles; wherein when the tie locks on the shutter member the first engagement means engages the first wall at the point the tie passes through the first wall, and the second engagement means engages the second portion of the shutter member; and wherein the tie is adapted to brace the first wall against the second portion when a force is applied to the first side of the first wall.
2. A shuttering system as claimed in Claim 1, wherein the shutter member comprises a pre-formed metal sheet having a length of uniform profile.
3. A shuttering system as claimed in Claim 1 or 2, wherein the tie is made from a less corrosive material than the shutter member.
4. A shuttering system as claimed in any preceding claim comprising a plurality of identical shutter members arranged to be attached together end to end to form an extended shutter of a desired length having at least one tie per shutter member.
5. A shuttering system as claimed in Claim 4 further comprising a plurality of connecting plates to fasten adlacent shutter members together so that they may abut end to end without overlap.
6. A shuttering system as claimed in Claim 4 or 5 wherein the profile of the shutter members permits them to be nested or partly nested together prior to assembling the tie on the shutter member.
7. A shuttering system as claimed in any preceding claim, wherein the first wall of the shutter member is taller than the second wall.
8. A shuttering system as claimed in any preceding claim, wherein the tie is adapted to be received in the shutter member from the second side of the first wall.
9. A shuttering system as claimed in any preceding claim, wherein the tie is substantially linear, and wherein, when locked in place, the tie extends through the first wall at an angle with respect to the base.
10. A shuttering system as claimed in Claim 9, wherein the tie is angled at between 30° and 600 with respect to the base.
11. A shuttering system as claimed in any preceding claim, wherein, when locked in place, the tie is perpendicular to the first wall.
12. A shuttering system as claimed in any preceding claim, wherein the tie abuts the base.
13. A shuttering system as claimed in any preceding claim, wherein the tie comprises a foot, and wherein the second engagement means is provided on the foot.
14. A shuttering system as claimed in Claim 13, wherein the foot is formed integrally with the rest of the tie.
15. A shuttering system as claimed in Claim 13 or 14, wherein the tie comprises a main linear body and a foot, and wherein the foot projects at 900 from the main linear body of the tie.
16. A shuttering system as claimed in any preceding claim, wherein the first engagement means engage the first wall above and/or below the aperture in the first wall adapted to receive the tie.
17. A shuttering system as claimed in any preceding claim, wherein the first engagement means comprises at least one protrusion on the tie, wherein the protrusion or protrusions are adapted to engage the second side of the first wall.
18. A shuttering system as claimed in any preceding claim, wherein the second engagement means comprises a protrusion adapted to engage with a notch on the second portion.
19. A shuttering system as claimed Claim 18, wherein the protrusion of the second engagement means is adapted to engage with a notch on the second wall.
20. A shuttering system as claimed in any preceding claim, wherein a top edge of at least one of the first wall and the second wall is an n-shaped edge positioned and arranged to be embedded in thesettable material.
21. A shuttering system as claimed in any preceding claim, wherein the first wall comprises one or more further openings, wherein the one or more further openings are adapted to allow settable material to pass through the first wall.
22. A shuttering system as claimed in any preceding claim, wherein the base of the shutter member further comprises an anchoring means adapted to fit the shutter member to a surface on which the concrete is to be poured.
23. A method of constructing a structure from concrete or other settable material on a site, the method comprising: taking at least one shutter member, wherein the shutter member comprises a first portion including a first wall with a first side and a second side opposite the first side, and a second portion including a base and a second wall, wherein the second side of the first wall and the second portion define a cavity; taking at least one separate tie, wherein the tie comprises a first engagement means and a second engagement means; assembling the tie on the shutter member by passing the tie through an aperture in the first wall and positioning the tie so that the tie projects from both sides of the first wall and is adapted to be embedded in settable material provided at the first side of the first wall and in the cavity; clipping the tie in place against the resilience of the shutter member so that the tie is locked on the shutter member when the shutter member resiles; wherein when the tie is locked on the shutter member the first engagement means engages the wall at the point the tie passes through the wall, and the second engagement means engages the second portion of the shutter member; anchoring the shutter member in place on the site; and pouring settable material against at least the first wall and into the cavity) wherein the tie is adapted to brace the first wall against the second portion when a force is applied to the first side of the first wall by the settable material.
24. A shuttering system substantially as hereinbefore described with reference to, and/or as illustrated by, the accompanying drawings.
25. A method of constructing a structure substantially as hereinbefore described with reference to the accompanying drawings.