AU2011253896A1

AU2011253896A1 - Improvements in or relating to concrete forming and methods therefor

Info

Publication number: AU2011253896A1
Application number: AU2011253896A
Authority: AU
Inventors: Derek John Halcrow
Original assignee: HALCROW TECHNOLOGY Ltd
Current assignee: HALCROW TECHNOLOGY Ltd
Priority date: 2010-12-13
Filing date: 2011-12-09
Publication date: 2012-06-28
Anticipated expiration: 2031-12-09
Also published as: AU2011253896B2; NZ589887A

Abstract

A reusable slab forming apparatus adapted to enable forming of a cementitious or other material foundation slab in place, comprising or including: a side shuttering member 5 extending in an elongate direction, having a first forming surface thereon located between an upper portion and a lower portion; an edge forming member adapted to be removably mounted to at least part of said side shuttering member via said upper portion, that when mounted to said at least part of said side shuttering member, is adapted to define a rebate in at least an edge of said foundation slab, said edge forming member of substantially 10 polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including: an upper part adapted to indicate a level of said cementitious or other material when poured; a lower external surface of said edge forming member, that when mounted to said upper portion, slopes upwardly and away from said side shuttering member; and at least one support 15 member adapted to releasably engage with at least said side shuttering member to, in use, support said side shuttering member in a vertical orientation with said elongate direction running substantially horizontal; wherein said side shuttering member at least in part defines a periphery within which said cementitious or other material can be poured to form a foundation slab in place, and wherein when said cementitious or other material has 20 at least in part cured, said reusable slab forming apparatus can be removed and is able to be reused to form another foundation slab.

Description

DSC508537AUPR 2 301957393 TECHNICAL FIELD OF THE INVENTION The present invention relates to apparatus and methods for forming concrete slabs for example for use in the building industry, and in particular, though not solely the present 5 invention is directed to concrete flooring slabs that are poured in location. BACKGROUND OF THE INVENTION In the construction of buildings, whether private or commercial, there is the need for a 10 foundation of the building. This serves as the base platform on to which the building is constructed. There are many different types of foundations and the particular one this invention is directed towards is for slabs, also known as raft floors or raft foundations. These are typically manufactured from concrete and are poured in location at the building site. 15 There are several reasons why the flooring slab is poured in location. Firstly it is often cheaper to bring the uncured concrete to the building site rather than construct the slab offsite and transport it in cured form to the site. Secondly, the size of many complete building slabs is larger than typical transport solutions will allow. Thirdly if the floor slab is 20 made from multiple parts and then brought on site and joined then there are issues of water tightness, for example from moisture from below. Therefore one standard way of forming a foundation is to pour it on site at the building location. Typically such pouring is into a pre-prepared location that is surrounded by wooden 25 boxing to form raised sides so that the slab sits proud of the surrounding ground. Utilities are located within the periphery of the wooden boxing prior to pouring, for example, water, internet, electricity and waste water, and gas for example. Reinforcing is also located in place by way of mesh and reinforcing bar, again prior to pouring. Blocks of material may also be provided within the periphery of the boxing to provide insulation and void filling 30 purposes, for example large polystyrene blocks. There may also be a moisture barrier between the ground and slab prior to filling, for example a polyethylene or similar sheet that runs across the entire slab for water proofing and moisture purposes. There is also the need when casting such foundation slabs to provide various detail in or 35 on the slab or on part of the slab, to aid in the subsequent construction process.

3 For example when the subsequent building will be a block or brick, joinery or other cladding materials or similar construction at least of part of the slab then it is standard practise to rebate those areas of the slab where the blocks will sit, for example the edge locations. 5 Typical solutions in the prior art to achieve this have been ad hoc in so far as they are done onsite from standard boxing materials which are normally of wood. These are often cut onsite and nailed or screwed into place. The finish is often inconsistent and subsequent re-working is often required before building construction can start. Such 10 boxing methods are inconsistent not only from slab to slab, but often between parts of the slab itself, and are less than desirable. Further the boxing material must be delivered onsite, cut to size, positioned, and is normally thrown away after the flooring slab material has cured. 15 Such solutions that exist in the prior art also often will leave untidy edges and rebates or foundation slabs with large steps in their top surfaces which either require remedial work or otherwise are unsightly and untidy. Other systems that exist cannot produce a foundation slab with both rebated and non-rebated edges, they require either a different system, adapting, or post pour re-working. Some systems of the prior art also rely on the 20 reinforcing to hold the formwork and thus require post pour reworking, for example plastering and sealing to cover holes where connections are made to or with reinforcing bar or mesh within the foundation slab. Such other and similar systems also are not self supporting in the absence of the reinforcing or reinforcing mesh. 25 in this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or 30 form part of the common general knowledge in the art. It is an object of the present invention to provide an improved concrete slab forming method and apparatus, or to overcome the above shortcomings of the prior art, or address the above desiderata, or to at least provide the public with a useful choice. 35 BRIEF DESCRIPTION OF THE INVENTION 4 In a first aspect the present invention may be said to broadly consist in a reusable slab forming apparatus adapted to enable forming of a cementitious or other material foundation slab in place, comprising or including: a side shuttering member extending in an elongate direction, having a first 5 forming surface thereon located between an upper portion and a lower portion; an edge forming member adapted to be removably mounted to at least part of said side shuttering member via said upper portion, that when mounted to said at least part of said side shuttering member, is adapted to define a rebate in at least an edge of said foundation slab, said edge forming member of substantially 10 polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including: an upper part adapted to indicate a level of said cementitious or other material when poured; a lower external surface of said edge forming member, that when mounted 15 to said upper portion, slopes upwardly and away from said side shuttering member; and at least one support member adapted to releasably engage with at least said side shuttering member to, in use, support said side shuttering member in a vertical orientation with said elongate direction running substantially horizontal; 20 wherein said side shuttering member at least in part defines a periphery within which said cementitious or other material can be poured to form a foundation slab in place, and wherein when said cementitious or other material has at least in part cured, said reusable slab forming apparatus can be removed and is able to be reused to form another foundation slab. 25 Preferably said reusable slab forming apparatus is of lightweight construction and individual components are easily handle-able by one person, even when in relatively long lengths. 30 Preferably said reusable slab forming apparatus does not extend above the desired level of the foundation slab to be poured so there is little to interfere with the pour, location of machinery, levelling of the foundation slab, removal of surface water. Preferably there is an upper external surface on said upper part that defines said level. 35 Preferably said side shuttering member is of thin walled form.

5 Preferably said side shuttering member is "C" shaped in cross section perpendicular to said elongate direction. Preferably said edge forming member is substantially hollow in said cross section. 5 Preferably in use said first forming surface is substantially planar. Preferably in use said first forming surface is substantially vertically oriented. 10 Preferably said edge forming member has a mounting tab extending from said upper part to engage with a mating region on said upper portion. Preferably said mounting tab extends, in use, horizontally and engages with said mating region, which is likewise, horizontal. 15 Preferably said mating region, when said edge forming member is not present, indicates a level of said cementitious or other material when poured. Preferably said edge forming member is releasably engaged with said side shuttering 20 member by at least one fastener. Preferably there is a plurality of fasteners to releasably engage said side shuttering member to said edge forming member. 25 Preferably said fasteners extend from said side shuttering member or said edge forming member or both and penetrate said edge forming member or said side shuttering member or both. Preferably said mounting tab, in use, sits above and on said mating region when engaged 30 thereto. Preferably said fasteners extend through said edge forming member and said side shuttering member. 35 Preferably said fasteners pass through said mating region from said mounting tab. Preferably said fasteners are chosen from any one or more of the following: 6 - self tapping threaded fasteners; - a threaded bolt and nut; - a threaded rod and nut; or - quick release fasteners, including rods and split pins. 5 Preferably said edge forming member has a further sloping external surface extending between said lower external surface and said upper external surface. Preferably said lower external surface, in use, is at an angle of between 1 degree and 10 10 degrees to the horizontal. Preferably said lower external surface, in use, is at an angle of between 3 and 4 degrees. Preferably said lower external surface, in use, is at an angle of approximately 3 degrees. 15 Preferably said further sloping external surface is at a greater upward angle to the horizontal than said lower external surface. Preferably said further sloping external surface, in use, is at an angle of between 45 20 degrees and 70 degrees to the horizontal. Preferably said further sloping external surface, in use, is at an angle of between 50 and 60 degrees. 25 Preferably said further sloping external surface, in use, is at an angle of approximately 56 degrees. Preferably where said edge forming member, when of hollow cross-section, there are stop-ends to blank off said hollow cross section. 30 Preferably said stop ends are portions affixed, whether permanently or releasably, to said edge forming member they are to blank off. Preferably said stop ends are short sections of edge forming member with a blanked off 35 end, or ends. Preferably there are jointer shells to run between abutting lengths of edge forming 7 members. Preferably there are preformed sections of edge forming member to fit corners, whether internal or external, of said side shuttering members. 5 Preferably there is at least one support engagement portion between said at least one support member and a side shuttering portion it is to support. Preferably there are a plurality of said at least one support engagement portion on said at 10 least one support member. Preferably there are a plurality of said at least one support member. Preferably said at least one support member can perform its function whether at one end 15 of, midway between ends, or at a corner of said side shuttering portion(s) it is to support. Preferably said edge forming member is of a cross-sectional size as needed to form the rebate desired, for example for brick, block, joinery, wooden or other cladding, or as needed to meet a building specification. 20 Preferably said rebate formed has an angled lower surface to prevent pooling of fluids and encourage their run off. In another aspect the present invention may be said to broadly consist in a method of 25 forming a foundation slab of cementitious or other material on a ground or other surface ("ground surface") for subsequent construction on, comprising or including the steps of: erecting at least one side shuttering member with a forming surface thereon, on said ground surface to at least in part define a perimeter surface to form a side of said foundation slab; 30 retaining said at least one side shuttering member with at least one support member, and releasably engaging said at least one support member and said at least one side shuttering member to each other; locating at least one edge forming member in releasable engagement on an upper portion of said at least one side shuttering member; and 35 wherein said at least one edge forming member defines an external second forming surface said second forming surface includes; an upper part adapted to indicate a level of said cementitious or other material when 8 poured; a lower external surface, that when engaged to said upper portion, slopes upwardly and away from said side shuttering member; locating within said perimeter any one of more of the following; 5 0 moisture-proof membranes, * utility ducting (for example water, gas, heat, electrical, and communications), * waste ducting, and * reinforcing mesh or bar, 10 pouring said cementitious or other material into said periphery to thus form said foundation slab, removing said at least one side shuttering member, said at least one support member and said at least one edge forming member once said cementitious or other material has cured to a point where it can retain its shape. 15 Preferably said ground surface is prepared prior to the step of locating said at least one side shuttering member including levelling and other performing or profiling of said ground surface the foundation slab is to be located or formed on. Preferably there is a release agent applied to said forming surface and said external 20 second forming surface. Preferably there is a plurality of side shuttering support members to define at least in part said periphery. 25 Preferably said plurality of side shuttering support members define said entire periphery. Preferably there is a plurality of said at least one support member. Preferably said support members are located at ends of each of said side shuttering 30 members, for example on corners, Preferably said support members are located between ends of said side shuttering members. 35 Preferably said lower external surface, in use, is at an angle of between 3 and 4 degrees to the horizontal.

9 Preferably said lower external surface, in use, is at an angle of approximately 3 degrees to the horizontal. Preferably said edge forming member is of a cross-sectional size as needed to form the 5 rebate desired, for example for brick, block, joinery, wooden or other cladding, or as needed to meet a building specification. In another aspect the present invention may be said to broadly consist in a method of providing a formwork to subsequently form a cementitious or other material foundation 10 slab for subsequent construction on, comprising or including the steps of, erecting at least one side shuttering member with a forming surface thereon, on a ground surface to at least in part define a perimeter surface to form a side of said foundation slab, retaining said at least one side shuttering member with at least one support member, and releasably engaging said at least one support member and said at least one side 15 shuttering member to each other, and locating at least one edge forming member in releasable engagement on an upper portion of said at least one side shuttering member, wherein said at least one edge forming member defines an external second forming surface said second forming surface includes: 20 an upper part adapted to indicate a level of said cementitious or other material when poured; a lower external surface, that when engaged to said upper portion, slopes upwardly and away from said side shuttering member. 25 In yet a further aspect still the present invention may be said to broadly consist in a foundation slab or a building including a foundation slab formed by: a side shuttering member extending in an elongate direction, having a first forming surface thereon located between an upper portion and a lower portion; an edge forming member adapted to be removably mounted to at least part of said side 30 shuttering member via said upper portion, said edge forming member of substantially polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including: an upper part adapted to indicate a level of said cementitious or other material when poured; 35 a lower external surface of said edge forming member, that when mounted to said upper portion, slopes upwardly and away from said side shuttering member; and at least one support member adapted to releasably engage with at least said side 10 shuttering member to, in use, support said side shuttering member in a vertical orientation with said elongate direction running substantially horizontal; wherein said side shuttering member and said edge forming member at least in part define a periphery within which said cementitious or other material can be poured to form 5 a foundation slab in place, and wherein when said cementitious or other material has at least in part cured, said reusable slab forming apparatus can be removed and is able to be reused to form another foundation slab. In yet a further aspect again the present invention may be said to broadly consist in a kit 10 of parts to provide a re-usable formwork adapted to produce a foundation slab, comprising or including; a side shuttering member extending in an elongate direction, having a first forming surface thereon located between an upper portion and a lower portion; an edge forming member adapted to be removably mounted to at least part of said 15 side shuttering member via said upper portion, said edge forming member of substantially polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including, an upper part adapted to indicate a level of said cementitious or other material 20 when poured; a lower external surface of said edge forming member, that when mounted to said upper portion, slopes upwardly and away from said side shuttering member; and at least one support member adapted to releasably engage with at least said side shuttering member to, in use, support said side shuttering member in a vertical 25 orientation with said elongate direction running substantially horizontal. In yet a further aspect still the present invention consists in a reusable slab forming apparatus as herein described with reference to any one or more of the accompanying drawings. 30 In yet a further aspect still the present invention consists in a method of forming a foundation slab as herein described with reference to any one or more of the accompanying drawings. 35 In yet a further aspect still the present invention consists in a method of providing a formwork as herein described with reference to any one or more of the accompanying drawings.

11 In yet a further aspect still the present invention consists in a foundation slab or a building including a foundation slab as herein described with reference to any one or more of the accompanying drawings. 5 As used herein the term "and/or" means "and" or "or", or both. As used herein "(s)" following a noun means the plural and/or singular forms of the noun. 10 The term "comprising" as used in this specification means "consisting at least in part of". When interpreting statements in this specification which include that term, the features, prefaced by that term in each statement, all need to be present, but other features can also be present. Related terms such as "comprise" and "comprised" are to be interpreted in the same manner. 15 It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7). 20 The term foundation slab as used in this specification means a slab that is used as the foundation for a building or similar construction, but also means a slab even if it does not form part of a foundation of a building or similar construction, for example a flat slab for a drive, pathway or similar. 25 The term cementitious material as used in this specification means a material such as for example concrete that cures to form a solid concrete like mass, and includes concrete and other similar materials that undergo a chemical or similar reaction to go from a flowing or flowable material or materials to form a stable solid material and include materials such as 30 epoxies, plastics materials, polymers and polymeric materials. The entire disclosures of all applications, patents and publications, cited above and below, if any, are hereby incorporated by reference. 35 This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements and features, and 12 where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. 5 Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS 10 Preferred forms of the present invention will now be described with reference to the accompanying drawings in which; Figure 1 is a vertical cross-section through the edge forming member of one possible shape along lines A-A of Figure 2; 15 Figure 2 is an isometric view of a partial length of edge forming member showing in the foreground the blanked off end. Thus, this section can be used as a stop-end to prevent ingress of concrete into the hollow form of the edge forming member; 20 Figure 3 is an isometric view of a jointer shell to join the gap between adjacent lengths of edge forming member; Figure 4 is an isometric view of an external corner edge forming member, in the particular form shown it has blank ends of short extension. However, in other embodiments it may 25 extend further in each direction; Figure 5 is a similar view to that of Figure 4 showing an edge forming member with blank ends to form a corner region for an internal corner; 30 Figure 6 is an end isometric view of the side shuttering member of the present invention; Figure 7 is an isometric view of a support member used to support and retain the side shuttering member and the formwork as a whole; 35 Figure 8(a) is a plan view of two lengths of side shuttering member and a support member showing an internal corner; 13 Figure 8(b) is an isometric plan view of the same configuration of corner of Figure 8(a); Figure 9(a) is a similar plan view to that of 8(a) but for an external corner; 5 Figure 9(b) is a plan isometric view of the external corner of 9A; Figure 10 is a similar view to that of Figure 9B of an external corner in isometric view; Figure 11 is a perspective view of a corner section of edge forming member and linear 10 section of edge forming member; Figure 12 is a similar view to that of Figure 11, with the addition of a jointer shell between the corner and elongate edge forming members. 15 Figure 13 is a plan perspective view of a corner in internal corner edge forming member resting on the side shuttering members; Figure 14 is a plan perspective view of an external corner arrangement of side shuttering members and support member; 20 Figure 15 is a similar view to that of Figure 14 but for an internal corner, showing one preferred form of fastening of the side shuttering members to the support member; Figure 16 is a plan perspective view of an internal corner of Figure 15; 25 Figure 17(a) is a side sectional view of unformed ground surface; Figure 17(b) is a similar view to that of 17(a) showing the ground surface scraped flat and/or profiled, together with an assembly of side shuttering members, support members, 30 and edge forming member; Figure 17(c) is a plan view of the resulting formwork showing the location of utilities including electricity or similar, waste water outlets, and reinforcing including mesh and reinforcing bar and the location of one section of edge forming member and jointing 35 member for an external corner.

14 Figure 17(d) is a plan view similar to that of 17(c) showing the pouring of concrete into the formwork and over the reinforcing and other parts present; Figure 17(e) is a side view of the resulting foundation slab including showing the edge 5 rebate the edge forming members have created in the concrete; Figure 17(f) is a detail A from Figure 17(e); Figure 18 shows a cross sectional view through B-B of Figure 17(d) showing the effect 10 the lowermost sloping surface of the edge forming member has in that it allows air bubbles that otherwise would be entrained or trapped to move up to the surface, and a surface on the upper region of the edge forming member to act as a guide for screeding or floating the top surface of the foundation slab when pouring the concrete; 15 Figure 19 is a number of views of further side support member embodiments, with a two piece arrangement driven into the ground in side view at (a), and close up of the top mounting arrangement at (d), a further variation to this shown in side view driven into the ground at (b), and in isometric view in (e), and a further triangulated side support member in side view in (c), and in isometric in (f); and 20 Figure 20 shows at (a) an end view of the side support member, (b) an end view of a fixing bracket to engage within the side support member, and (c) the fixing bracket mounted within the side support member. 25 DETAILED DESCRIPTION OF THE INVENTION Preferred embodiments of the present invention will now be described with reference to Figures 1 through 20. 30 Shown in Figure 1 is a cross section of the preferred embodiment of an edge forming member 7 of the present invention in one particular shape to form a brick or block work rebate 15. As shown in Figure 1, the edge forming member 7 is of substantially polygonal cross-section when sectioned through the vertical plane when in use. However the edge forming member 7 may be of any shape required or desired to form a rebate 15 or other 35 detail as required for a construction technique or material (for example bricks or blocks or different dimensions, joinery, wood, or cladding), or as required for local territorial authority specifications. For example some construction techniques or territorial 15 authorities may require different or deeper dimensions. As shown the rebate 15 formed has an angled lower surface to prevent pooling of fluids and encourage their run off. The edge forming member 7 shown defines an external second forming surface 8 being 5 the presented periphery of the polygonal shape. An upper part 9 defines a level 10 and in the preferred embodiment the level 10 is an upper external surface 16. A lower external surface 11 is also shown. In the preferred embodiment, this angles upwards (and away from the side shuttering member 2 when it is installed thereto). The function of the lower external surface 11 and the level 10 will be explained below. 10 The angle of the lower external surface 11 to the horizontal can be in the range of 1 degree to 10 degrees when installed. The preferred embodiment has an angle of approximately 3 to 3.2 degrees. However, various other slopes will be applicable and appropriate when the function of the lower external surface 11 is described. As can be 15 seen in Figure 1, the edge forming member 7 is preferably hollow and in the preferred embodiment it is an extruded product, such as, for example, but not limited to, extruded aluminium. In other embodiments, the material may be an extruded or pultruded material, such as 20 plastics, composites and the like, or folded or fabricated steel or aluminium. The edge forming member 7 could be made of any material, provided it is resilient, dimensionally stable and presents a smooth external second forming surface 8 which is easily re-usable. Whilst timber is a possible material, it is likely the least desirable and often impractical for the present invention, given its cost for well-finished wood, dimensional stability over time, 25 the conditions the edging will experience, its weight and longevity. In the preferred embodiment, the edge forming member 7 has a mounting tab 17 extending in the horizontal direction from the upper part 9. The function of this mounting tab 17 will be described below. 30 When the edge forming member 7 is made from a thin hollow extrusion, such as, for example, aluminium, then it may also be desirable to have the mounting tab 17 extending into the body and particularly the upper part 9 of the edge forming member 7 to reinforce its connection with the edge forming member 7. 35 There is also a further sloping surface 20 between the lower external surface 11 and the upper part 9. The further sloping surface 20 provides a further finish to the rebate 15 (as 16 shown in Figure 17f) when formed in the foundation slab 14, and provides sufficient spacing of any blockwork 45 that is located on the rebate 15. Shown in Figure 2 is a stop end 21 that includes a blanked off end 46. The function of this 5 stop end 21 is to provide a blanked off end 46 to the edge forming member 7 when, for example, the edge forming member 7 is only required to form a rebate in a foundation slab 14 along part of the length of the foundation slab 14. The blanking off can be achieved in a number of ways, such as, for example, fixing a blanking portion 22 to the open end of a length of the edge forming member. This may be made of similar material 10 to the stop end 21, and may for example be welded, glued, frictionally fitted, or similar. The edge forming member 7 may be cut into shorter lengths to form stop ends 21 or long lengths of edge forming member 7 may have blanked off ends 46 to form long lengths that have blanked off ends 46. The blanked off end 46 is to prevent ingress of the foundation slab 14 material and other debris into the cavity of the edge forming member 7 when it is 15 hollow. This other purpose of the blanked off end 46 of the edge forming member 7 is to provide a clean finish to the foundation slab rebate 15. It also can reinforce the otherwise open end of the stop end 21. Shown in Figure 3 is a jointer shell 23. In a preferred embodiment this is made from a 20 folded piece of sheet material, such as thin gauge sheet steel. However, in other embodiments it may be extruded or formed in any other known way from known materials. A function of the jointer shell 23 is to cover the void 47 that would otherwise occur between adjacent portions of edge forming member 7 and it is shown in use in Figure 12 between a corner form of edge forming member 24 and a butting length of edge forming 25 member 7. The foundation slab 14 may consist, when formed, of external corners 26, that is, corners that poke "outwards" from the body of the finished foundation slab 14, as well as internal corners 25, being those corners that poke "into" the body of the finished foundation slab 30 14, such as indicated in Figures 8 and 9. To speed up the assembly of the foundation system, then preformed internal corner forms 24A and external corner forms 24B as shown in Figures 4 and 5 respectively are provided. In a preferred form, these also have blanked off ends 46 and are joined to adjacent lengths of edge forming member 7 as required by jointer shells 23 to close off any void 47. In other situations such as for when 35 a jointer shell 23 would prevent ingress of debris, then the ends or end of the corner portions 24A and 24B may optionally be left open.

17 Shown in Figure 6 is a side view of the side shuttering member 2. In a preferred form, the side shutter member 2 is of substantially C shaped cross section in the vertical plane as shown, however, in other embodiments it may be of a box-like form having a rectangular cross section in the vertical plane. The side shuttering member 2 performs several 5 functions. It provides a first forming surface 4 that forms part of the periphery or perimeter surface 13 for forming of the foundation slab 14. It also provides, via its upper portion 5, a mating region or surface 18 for mounting, via the mounting tab 17, the edge forming member 7. The mating region or surface 18 can define a level 10 for forming or levelling foundation slab 14 material to, when for example the edge forming member 7 is not 10 present. The side shuttering member 2 also consists of a lower portion 6 that would usually rest on the ground surface 31 as shown in Figure 17(b) when the formwork of the present invention is assembled. Being of thin gauge metal construction, the side shuttering 15 member in the form shown in Figure 6 is light, yet dimensionally stable and sufficiently resilient that it can be applied and removed and re-used many times for the forming of foundation slabs 14. It is also beneficial for cleaning the side shuttering member 2 of adherent materials to the first forming surface 4 that it can be hammered or elasrically twisted out of plane to loosen the adherent materials whilst not damaging or mis-shaping 20 its overall shape and, more importantly, the first forming surface 4. Present also on the side shuttering member 2 are apertures 38 to retain or receive fasteners for releasably engaging the edge forming member 7 and/or the support members 12 to the side shuttering member 2 to thereafter form the formwork for forming 25 of the foundation slab 14. Shown in Figure 7 is a support member 12. In the preferred embodiment, this is a vertically elongate peg or vertical support 48 that can be driven into the ground surface 31, but in other embodiments, they simply sit on top of the ground surface 31. In yet other 30 embodiments still, this may be a triangulated or similar brace where, for example, the ground is too firm or rocky or uneven to drive a support member there into, or further lateral support is required. Down vertical faces of the support member 12 fasteners 19 are shown protruding from the 35 vertical faces and are adapted to engage the apertures 38 on or near the first forming surface of the side shuttering member 2. One example of the preferred form of engagement of the support member 12 and the side shuttering member 2 is shown in 18 Figures 14 and 15 showing fasteners 19 extending from the support member 12 through apertures 38 in the side shuttering member 2 and fastened by complementary threaded nuts. 5 Further embodiments of the support member 12 are shown in Figure 19(a) through (f). A triangulated fixed or pivoting two peg system is shown in Figures 19(a) and 19(b). This consists of a vertical support 48 fixed to an angled support 49 via a fixing or pivoting point 50. This can attach to the side shuttering member via fasteners as described below. If the two members can pivot this allows for choosing the location of ground penetration of 10 at least the angled support 49 for example to avoid a rock or similar, or to allow for greater lateral support. A similar variation to that of Figures 19(a) and 19d) is shown in Figures 19(b) and 19(e). The vertical support 48 and angled support 49 may be solid hollow, round, square or any 15 other profile that may be appropriate for the purpose. The vertical support 48 and angled support 49 may have a metal foot 59 attached at an appropriate distance from the bottom of the members to allow better holding in soft ground conditions. The vertical support 48 and angled support 49 are driven into ground as shown and fixed together with an appropriate clamping system or cuff 51. 20 They may have a cuff 51 to join the vertical support 48 and the angled support 49. Similarly again if the two members can pivot this allows for choosing the location of ground penetration of at least the angled support 49 for example to avoid a rock or similar, or to allow for greater lateral support. A mounting bracket 52 is present on the vertical 25 support 48 to engage with the side shuttering member. A further variation is shown in Figures 19(c) and 19(f), consisting of a fixed triangular side support 12 that in use is a rigid triangle of welded or otherwise fabricated channel section, an angle brace 57 is attached and may be as shown or smaller angle braces may be 30 welded to the corner if appropriate. Ground securing pins 54 are optionally present and can be moved along the horizontal support 55 if necessary, and can be driven into the ground surface 31 to anchor the side support 12, and may be of a coarse threaded stock or some other product such as 'Reid Bar' 35 Each of these variations can be fixed to their side support member first and then driven into the ground (if necessary) or may be located in place, driven into the ground (where necessary) and then affixed to the side shuttering member 2 they are to support.

19 A fixing bracket 53 is shown in Figure 20b that can slide into the interior "C" shape of the side shuttering member 2, as shown in Figure 20(c). The fixing bracket 53 is designed to be a relatively close fit into the interior shape of the side shuttering member 2. The fixing 5 bracket 53 may be engaged by holding at an angle and engaging the of the fixing bracket 53 into bottom of the side shuttering member 2, then push the fixing bracket 53 to the vertical position and the top of the fixing bracket 53 will engage into the top of the side shuttering member 53. 10 This in turn can be fastened via fasteners through slots 56 to a mating slot or slots 56 in the mounting brackets 52 of the support member 12. In use the support member 12 can be placed on the ground 31 adjacent to the side shuttering member 2 it is to support. Two pins 54 are driven through the holes in the 15 horizontal support 55 or the bottom sections of the vertical member 48 and angled member 49 are driven into the ground 31 to a suitable depth and then locking nuts 58 (in the case of the version in Figures 19c and f) are wound down to hold the support member 12 firmly in position. Packers (not shown) may be placed under the horizontal support 55 to roughly level the support member 12. 20 The fixing bracket 53 is engaged into the side shuttering member 2 and held against the vertical member 48 (or equivalent) of the support member 12. Bolts and nuts or other appropriate fastenings are introduced through the vertical slot on the Ground Support and the slots on the fixing bracket 53 and support member 12, this allows both vertical and 25 horizontal adjustment to be made before tightening of fastenings. In Figure 14 the assembly is shown to form an external corner 26 in the foundation slab 14 and in Figure 15 the assembly is shown to form an internal corner. Similar arrangements are shown in Figures 8(a) and (b) for an internal corner 25 showing the 30 preferable location for the support member 12 and side shuttering members 2. Similarly in Figures 9(a) and (b) is shown for an external corner 26 the arrangement of the side shuttering members 2 and the support member 12. Shown in Figures 8 and 9 and also Figures 14 and 15, the support member 12 is at an 35 end 28 of each of the side shuttering members 2. Similarly, however, the support member 12 could be located midway 29 along a length of side shuttering member 2, for example, 20 when the length of slab 14 to be formed is relatively long and further support is needed to brace the side shuttering member 2. One end 28 of the side shuttering member 2 could also be closed off, such as shown in 5 Figures 14 and 15 to provide location for the apertures 38 for fasteners 19 from the support member 12. In other embodiments the apertures 38 may be located on the external facing surfaces of the support member 2, such as, for example, when the support member 12 is located 10 midway 29 along the length of the side shuttering member 2, such as, for example, shown in Figure 6. The first forming surface 4 on the side shuttering member 2 is preferably planar as shown in Figure 6 and when in use is oriented substantially vertically. The result on the 15 foundation slab 14 is a smooth planar vertically oriented edge face 40 as shown in Figure 17(f). The further sloping external surface 20 as shown in Figure 1 of the edge forming member 7 can vary in angle to the horizontal of between 45 and 70 degrees, and ideally is between 50 and 60 degrees, and in the preferred embodiment, is approximately 56 degrees. 20 The preferred use and method of the present invention to form a foundation slab 14 will now be described. Shown in Figure 17(a) is a cross-section of uneven ground 31 where it is desired to form a 25 foundation slab 14. Such a foundation slab 14 may be for the erection of a building 44 thereon or similar construction or may simply be the creation of a slab, such as for example, a driveway, path or similar. Equally, the invention may be used to form an edging or other form of concrete material 30 construction. Preferably the ground surface 31 is graded, flattened or otherwise shaped to provide a substantially flat ground surface as shown in Figure 17(b). Any profiling of the ground surface 31 can also be achieved at this stage, such as for example, the creation of a 35 foundation trench 36 where required and/or trenches for utilities and the like ducting. A plurality of side shuttering members 2 are then arranged to define at least in part a periphery or perimeter surface 13 for containment of the foundation slab 14 material when 21 poured. When the ground 31 is substantially flat, then the side shuttering members 2 may completely surround the area for the foundation slab 14 to be poured. Alternatively, where there is another forming surface available, for example, the side of a hill or other building then side shuttering members 2 are used only where required to complete in 5 encircling periphery 13. At least at corners 30, there are located support members 12 and where the run is sufficiently long of the side shuttering member 2, then they are also located at mid points 29 or where required for additional support, such as shown in Figures 17(b) and (c). The releasable engagement of the side shuttering members 2 to the support members 12 may be as described but may also be achieved by other 10 releasable engagements, for example, sliding hooks, catches, pins and split pins, and other know ways of attaching one part to another part in a releasable manner known in the art. During the location of the side shuttering members 2, or even beforehand if applicable, 15 lengths of edge forming members 7 are located in releasable engagement on the upper portion 5, being the upper presenting mating region or surface 18 of the side shuttering member 2. Where necessary also, corner forms 24A and B of the edge forming member 7 are located. 20 The releasable engagement of the edge forming member 7 to the side shuttering member 2 can be achieved by any means known to a person skilled in the art, such as, for example, threaded retention, self-tapping retention, posts on the side shuttering members 2 that engage with the edge forming member 7, posts on the edge forming member 7 that engage with the side shuttering member 2, hooks and eyes, overlapping engagements 25 that prevent floating upwards of the edge forming member 7 and other variations known in the art for retaining one item to another in a releasable engagement. During the forming of the periphery or perimeter surface 13, any one or more of the following can be located within the periphery, moisture barrier materials or moisture proof 30 membranes 32, utility ducting 33, waste ducting 34, reinforcing mesh and/or bar 35 and where necessary on the forming surfaces on the side shuttering members 2 and edge forming members 12, then a release agent may also be applied to enable easy release of the members from the cured or partially cured foundation slab 14. Once the periphery or perimeter surface 13 is provided and all edge forming members 7 required are in place, 35 including any jointer shells 23, then concrete or other similar material can be poured into the perimeter surface 13. As the concrete material is laid, a concrete float 41 and/or similar tooling can be used and run off the upper external surface 16 when the edge 22 forming member is in place to form a rebate 15, or the mating region or surface 18 when there is no rebate 15 required to provide the required level of the foundation slab 14. This will provide a smooth continuous foundation slab 14 once cured with rebates 15 5 formed where required in the edges 42 of the foundation slab 14 to take brick or block work or similar for the construction, or where a rebate may be required, such as for a short step or similar. The angling of the lower external surface 11 and further sloping surface 20 and their 10 function will now be described. As shown in Figure 18, the sloping of the surfaces 11 and 20 respectively will provide a path for otherwise entrapped air to move up and out from under the edge forming member 7 when the foundation slab material is poured. For example, when the concrete material 15 being formed is vibrated, air will move up through the concrete material and follow the path 43 shown and will leave a high quality finish in the rebate 15 when the edge forming member 7 is removed. This results in less honey combed concrete internally and reduced air voids at the edge forming members 7. This results in a stronger slab. 20 The resulting building 44 or other construction on top of the foundation slab 14 will therefore have the appropriate rebate 15 for blockwork 45 whilst also allowing for other construction techniques (such as, for example, weatherboard) in the construction. It is to be understood the rebate 15 or other detail formed can be for any purpose necessary or desired and therefore can take a multitude of forms which all fall within the ambit of this 25 invention. Once the concrete material has cured to a sufficient point where it is dimensionally stable then the edge forming members 7 and side shuttering members 2 and support members 12 can be removed to leave the foundation slab 14 in place. The members can then be 30 used for a further slab of identical form or be re-used or reconfigured for foundation slabs 14 of a different form. The resulting slab is cleaner and more consistent at its edges and rebates and allows for easier post working as needed, for example application of damp proofing and subsequent 35 construction.

23 The present invention may also be supplied as a kit of parts, consisting at least of support members 12, side shuttering members 2, edge forming members 7, jointer shells 23, stop ends 21, and corner portions 24 A and B as required. In some forms of the kit of parts, these may be supplied pre-cut and ready to assemble for the required foundation slab 14 5 to be formed, or may be cut to size by the person on site. In the preferred embodiment the side shuttering members 2 rest on the ground surface 31 and do not penetrate below the ground surface. The use of releasable engagements such as but not limited to threaded fasteners will allow easy construction and deconstruction of 10 the formwork consisting of the support members, side shuttering members 2 and edge forming members 7, jointer shells 23 and corner 24 and 25 as required, and their manufacture in a resilient dimensionally stable material such as, but not limited to, steel and/or aluminium, allows them to be easily cleaned down whilst being robust, for example, against water blasting (which timber is not) and that allows substantial re-use over many 15 foundation slab cycles. The reusable slab forming apparatus is of lightweight construction and individual components are easily handle-able by one person, even when in relatively long lengths. 20 Also the reusable slab forming apparatus does not extend above the desired level of the foundation slab to be poured so there is little to interfere with the pour, location of machinery, levelling of the foundation slab, removal of surface water The foregoing description of the invention includes preferred forms thereof. Modifications 25 may be made thereto without departing from the scope of the invention.

Claims

1. A reusable slab forming apparatus adapted to enable forming of a cementitious or other material foundation slab in place, comprising or including: 5 - a side shuttering member extending in an elongate direction, having a first forming surface thereon located between an upper portion and a lower portion; - an edge forming member adapted to be removably mounted to at least part of said side shuttering member via said upper portion, that when mounted 10 to said at least part of said side shuttering member, is adapted to define a rebate in at least an edge of said foundation slab, said edge forming member of substantially polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including: 15 . an upper part adapted to indicate a level of said cementitious or other material when poured; ii. a lower external surface of said edge forming member, that when mounted to said upper portion, slopes upwardly and away from said side shuttering member; and 20 - at least one support member adapted to releasably engage with at least said side shuttering member to, in use, support said side shuttering member in a vertical orientation with said elongate direction running substantially horizontal; wherein said side shuttering member at least in part defines a periphery 25 within which said cementitious or other material can be poured to form a foundation slab in place, and wherein when said cementitious or other material has at least in part cured, said reusable slab forming apparatus can be removed and is able to be reused to form another foundation slab. 30

2. An apparatus as claimed in claim 1 wherein said reusable slab forming apparatus is of lightweight construction and individual components are easily handle-able by one person, even when in relatively long lengths.

3. An apparatus as claimed in either of claims 1 or 2 wherein said reusable slab 35 forming apparatus does not extend above a desired level of said foundation slab to be poured so there is little to interfere with the pour, location of machinery, levelling of the foundation slab, or removal of surface water. 25

4. An apparatus as claimed in any one of claims 1 to 3 wherein said there is an upper external surface on said upper part that defines said level.

5 5. An apparatus as claimed in any one of claims 1 to 4 wherein said side shuttering member is of thin walled form.

6. An apparatus as claimed in any one of claims 1 to 5 wherein said side shuttering member is "C" shaped in cross section perpendicular to said elongate direction. 10

7. An apparatus as claimed in any one of claims I to 6 wherein said edge forming member is substantially hollow in said cross section.

8. An apparatus as claimed in any one of claims 1 to 7 wherein in use said first 15 forming surface is substantially planar.

9. An apparatus as claimed in any one of claims I to 8 wherein in use said first forming surface is substantially vertically oriented. 20

10. An apparatus as claimed in any one of claims 1 to 9 wherein said edge forming member has a mounting tab extending from said upper part to engage with a mating region on said upper portion.

11. An apparatus as claimed in claim 10 wherein said mounting tab extends, in use, 25 horizontally and engages with said mating region, which is likewise, horizontal.

12. An apparatus as claimed in either of claims 10 or 11 wherein said mounting tab, in use, sits above and on said mating region when engaged thereto. 30

13. An apparatus as claimed in any one of claims 10 to 12 wherein said mating region, when said edge forming member is not present, indicates a level of said cementitious or other material when poured.

14. An apparatus as claimed in any one of claims 1 to 13 wherein said edge forming 35 member is releasably engaged with said side shuttering member by at least one fastener. 26

15. An apparatus as claimed in claim 14 wherein there is a plurality of said fasteners to releasably engage said side shuttering member to said edge forming member.

16. An apparatus as claimed in either of claims 14 or 15 wherein said fasteners extend 5 from said side shuttering member or said edge forming member or both and penetrate said edge forming member or said side shuttering member or both.

17. An apparatus as claimed in any one of claims 14 to 16 wherein said fasteners extend through said edge forming member and said side shuttering member. 10

18. An apparatus as claimed in any one of claims 10 to 12 and 14 to 17 wherein said fasteners pass through said mating region from said mounting tab.

19. An apparatus as claimed in any one of claims 14 to 18 wherein said fasteners are 15 chosen from any one or more of the following: - self tapping threaded fasteners; - a threaded bolt and nut; - a threaded rod and nut; or - quick release fasteners, including rods and split pins. 20

20. An apparatus as claimed in any one of claims I to 19 wherein said edge forming member has a further sloping external surface extending between said lower external surface and said upper external surface. 25

21. An apparatus as claimed in claim 20 wherein said further sloping external surface is at a greater upward angle to the horizontal than said lower external surface.

22. An apparatus as claimed in either of claims 20 or 21 wherein said further sloping external surface, in use, is at an angle of between 45 degrees and 70 degrees to 30 the horizontal.

23. An apparatus as claimed in any one of claims 20 to 22 wherein said further sloping external surface, in use, is at an angle of between 50 and 60 degrees. 35

24. An apparatus as claimed in any one of claims 20 to 23 wherein said further sloping external surface, in use, is at an angle of approximately 56 degrees. 27

25. An apparatus as claimed in any one of claims 1 to 24 wherein said lower external surface, in use, is at an angle of between 1 degree and 10 degrees to the horizontal. 5

26. An apparatus as claimed in any one of claims 1 to 25 wherein said lower external surface, in use, is at an angle of between 3 and 4 degrees.

27. An apparatus as claimed in any one of claims 1 to 26 wherein said lower external 10 surface, in use, is at an angle of approximately 3 degrees.

28. An apparatus as claimed in any one of claims I to 27 wherein said edge forming member, when of hollow cross-section, has stop-ends to blank off said hollow cross section. 15

29. An apparatus as claimed in claim 28 wherein said stop ends are portions affixed, whether permanently or releasably, to said edge forming member they are to blank off. 20

30. An apparatus as claimed in either of claims 28 or 29 wherein said stop ends are short sections of edge forming member with a blanked off end, or ends.

31. An apparatus as claimed in any one of claims 1 to 30 wherein there are jointer shells to run between abutting lengths of edge forming members. 25

32. An apparatus as claimed in any one of claims 1 to 31 wherein there are preformed sections of edge forming member to fit corners, whether internal or external, of said side shuttering members. 30

33. An apparatus as claimed in any one of claims I to 32 wherein there is at least one support engagement portion between said at least one support member and a side shuttering portion it is to support.

34. An apparatus as claimed in any one of claims 1 to 33 wherein are a plurality of 35 said at least one support engagement portion on said at least one support member. 28

35. An apparatus as claimed in any one of claims 1 to 34 wherein are a plurality of said at least one support member.

36. An apparatus as claimed in any one of claims 1 to 35 wherein said at least one 5 support member can perform its function whether at one end of, midway between ends, or at a corner of said side shuttering portion(s) it is to support.

37. An apparatus as claimed in any one of claims I to 37 wherein said edge forming member is of a cross-sectional size as needed to form the rebate desired. 10

38. A method of forming a foundation slab of cementitious or other material on a ground or other surface ("ground surface") for subsequent construction on, comprising or including the steps of: erecting at least one side shuttering member with a forming surface 15 thereon, on said ground surface to at least in part define a perimeter surface to form a side of said foundation slab; retaining said at least one side shuttering member with at least one support member, and releasably engaging said at least one support member and said at least one side shuttering member to each other; 20 locating at least one edge forming member in releasable engagement on an upper portion of said at least one side shuttering member; and wherein said at least one edge forming member defines an external second forming surface said second forming surface includes; an upper part adapted to indicate a level of said cementitious or 25 other material when poured; a lower external surface, that when engaged to said upper portion, slopes upwardly and away from said side shuttering member; locating within said perimeter any one of more of the following; moisture-proof membranes, 30 utility ducting (for example water, gas, heat, electrical, and communications), waste ducting, and reinforcing mesh or bar, pouring said cementitious or other material into said periphery to thus form 35 said foundation slab, removing said at least one side shuttering member, said at least one support member and said at least one edge forming member once said cementitious or other material has cured to a point where it can retain its shape. 29

39. A method as claimed in claim 38 wherein said ground surface is prepared prior to the step of locating said at least one side shuttering member including levelling and other performing or profiling of said ground surface the foundation slab is to be 5 located or formed on.

40. A method as claimed in either of claims 38 or 39 wherein there is a release agent applied to said forming surface and said external second forming surface. 10

41. A method as claimed in any one of claims 38 to 40 wherein there is a plurality of side shuttering support members to define at least in part said periphery.

42. A method as claimed in any one of claims 38 to 41 wherein said plurality of side shuttering support members define said entire periphery. 15

43. A method as claimed in any one of claims 38 to 42 wherein there is a plurality of said at least one support member.

44. A method as claimed in any one of claims 37 to 42 wherein said support members 20 are located at ends of each of said side shuttering members.

45. A method as claimed in any one of claims 38 to 44 wherein said support members are located between ends of said side shuttering members. 25

46. A method as claimed in any one of claims 38 to 45 wherein said lower external surface, in use, is at an angle of between 3 and 4 degrees to the horizontal.

47. A method as claimed in any one of claims 38 to 46 wherein said lower external surface, in use, is at an angle of approximately 3 degrees to the horizontal. 30

48. An apparatus as claimed in any one of claims 38 to 47 wherein said edge forming member is of a cross-sectional size as needed to form the rebate desired.

49. A method of providing a formwork to subsequently form a cementitious or other 35 material foundation slab for subsequent construction on, comprising or including the steps of, erecting at least one side shuttering member with a forming surface 30 thereon, on a ground surface to at least in part define a perimeter surface to form a side of said foundation slab, retaining said at least one side shuttering member with at least one support member, and releasably engaging said at least one support member and said at 5 least one side shuttering member to each other, and locating at least one edge forming member in releasable engagement on an upper portion of said at least one side shuttering member, wherein said at least one edge forming member defines an external second forming surface said second forming surface includes: 10 an upper part adapted to indicate a level of said cementitious or other material when poured; a lower external surface, that when engaged to said upper portion, slopes upwardly and away from said side shuttering member. 15

50. A foundation slab or a building including a foundation slab formed by: a side shuttering member extending in an elongate direction, having a first forming surface thereon located between an upper portion and a lower portion; an edge forming member adapted to be removably mounted to at least part of said side shuttering member via said upper portion, said edge forming member 20 of substantially polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including: an upper part adapted to indicate a level of said cementitious or other material when poured; 25 a lower external surface of said edge forming member, that when mounted to said upper portion, slopes upwardly and away from said side shuttering member; and at least one support member adapted to releasably engage with at least said side shuttering member to, in use, support said side shuttering member in a 30 vertical orientation with said elongate direction running substantially horizontal; wherein said side shuttering member and said edge forming member at least in part define a periphery within which said cementitious or other material can be poured to form a foundation slab in place, and wherein when said cementitious or other material has at least in part cured, said reusable slab forming apparatus 35 can be removed and is able to be reused to form another foundation slab.

51. A kit of parts to provide a re-usable formwork adapted to produce a foundation 31 slab, comprising or including; a side shuttering member extending in an elongate direction, having a first forming surface thereon located between an upper portion and a lower portion; an edge forming member adapted to be removably mounted to at least part 5 of said side shuttering member via said upper portion, said edge forming member of substantially polygonal cross section perpendicular to said elongate direction, and which defines an external second forming surface said second forming surface including, an upper part adapted to indicate a level of said cementitious or other 10 material when poured; a lower external surface of said edge forming member, that when mounted to said upper portion, slopes upwardly and away from said side shuttering member; and at least one support member adapted to releasably engage with at least 15 said side shuttering member to, in use, support said side shuttering member in a vertical orientation with said elongate direction running substantially horizontal.

52. A reusable slab forming apparatus as herein described with reference to any one or more of the accompanying drawings. 20

53. A method of forming a foundation slab as herein described with reference to any one or more of the accompanying drawings.

54. A method of providing a formwork as herein described with reference to any 25 one or more of the accompanying drawings.

55. A foundation slab or a building including a foundation slab as herein described with reference to any one or more of the accompanying drawings.