Improvements in and Relating to the Construction of Walls or Panels

TECHNICAL FIELD OF THE INVENTION

The present invention relates to improvements in and relating to the construction of concrete walls or panels, in particular, but not exclusively to concrete walls or panels used in tilt slab construction.

BACKGROUND ART KNOWN TO THE APPLICANT

The construction of concrete walls has been known since at least Roman times with the construction of the Colosseum, the Forum and the like. More than two thousand years later, the use of concrete for the construction of walls and buildings in general has remained much the same. However, these days, an industry known generally as the "tilt slab" industry has developed where panels of metal (usually steel) reinforced concrete are cast either on or off site for use in the main, for the construction of external walls for warehouses, shopping complexes and increasingly homes, be they apartments or more conventional house types such as detached or semi detached.

Off site casting also known as "precast" carried out in a factory has the advantage that walls may be cast in advance of the main construction starting and may help in providing more consistent slabs or panels for a contractor inexperienced in using concrete panel construction methods.

However, such a method of construction suffers from the disadvantage that the precast slabs are of varying sizes and have now to be transported to the site on flat bed trucks for erection and this will involve time and may be very costly if the load is a particularly high or wide load necessitating a Police or other form of official escort to the site.

On site casting also known as "tilt up" uses either a temporary casting slab or the floor slab of the building under construction as its casting bed is potentially less costly as no transportation

costs are involved however, this system does tend to be more reliant on experienced contractors for the reasons specified above.

Stack casting, another process of casting panels (one on top of the other) is also well known in the trade and may be carried out on or off site with the inherent problems mentioned hereinabove. What is required is apparatus and a method of using that apparatus to provide a means of producing off site quality slabs at least "on site", even when using inexperienced contractors.

It is therefore an object of the present invention to go at least some way towards trying to alleviate the problem as specified above or to at least provide the public with a useful choice.

Furthermore, whilst the present invention is embodied in several different aspects, it will be apparent from this broad background review that each of these independent aspects are so linked as to form part of the same inventive concept.

STATEMENTS OF THE INVENTION

According to a first aspect of the present invention there is provided a method of forming a concrete slab for use in the construction or the tilt slab industry comprising the steps of providing a construction site with a transportable casting bed adapted to receive formwork; fitting the casting bed with formwork to form a mold; placing concrete forming material within the mold; allowing the concrete forming material to form concrete; removing the formwork; and moving the concrete slab formed into its final position on site.

To date, wall panels have been produced with dimensions to suit individual projects. The present invention provides a design approach and specialized casting equipment to enable standard dimension panels to be more easily and economically produced thus tending to alleviate the afore mentioned problems. In other words, the invention provides a modularized approach to wall panel design and construction to produce standard width panels on movable beds that can be used either on site or in a precast yard.

Reinforcing the concrete slab prior to its formation could be carried out using conventional reinforcing metal bars arranged in an array in the mold, however, preferably, the method further comprises the step of placing an integral grid of reinforcing material at an appropriate height

into the mold. In order to establish the right height the reinforcing material sits on a plurality of stools placed within the mold.

Preferably, the method further comprises the step of supplying all of the components to form the mold as part of a system for on site concrete slab production.

Preferably, the method further comprises the step of removing the casting bed from the site and making it available as a casting bed elsewhere.

The method could employ the use of a heat exchanger or some other form of bed, mold and/or mold contents warming apparatus to provide a means for warming the bed or mould and/or mold contents ^' .

Preferably, the method further comprises the step of supplying the mould with heat via an external heat source.

The invention includes _. within its scope a method substantially as herein described with reference to and/or as illustrated in any appropriate selection or combination of the accompanying drawings.

The invention further includes within its scope a concrete slab or tilt slab formed from the method specified herein.

According to a second aspect of the present invention, there is provided apparatus for forming a concrete slab for use in the construction or the tilt slab industry comprising: a transportable casting bed adapted to be fitted with formwork to form a mould; a number of pieces of formwork one or more of which are adapted to receive a number of formwork to transportable casting bed clamping members; a plurality of formwork to transportable casting bed clamping members and wherein the apparatus once assembled, forms a mould capable of receiving concrete forming material.

The apparatus could be supplied pre-assembled however preferably, the apparatus is a self assembly apparatus.

Preferably, the apparatus further comprises a grid of reinforcing material. This could be an array of metal bars that could be paint powder coated.

More preferably, the grid is an integral grid. Alternatively, a combination of one or more integral grids or one or more integral grids and one or more arrays of metal bars that form a non integral grid could be used. In either event, the use of at least one integral grid has the advantage of time saving when it comes to putting down the grid and it also enables a deskilled labour force to apply it with little chance of making an error. Typically, these reinforcing materials are placed onto stands that are the correct height for the slab that is to be formed. If an integral grid is used, it may be possible to dispense with some or all of the stands if the grid is provided with integral downwardly depending legs whereby in use, the grid was laid with the feet of the legs contacting the casting bed.

The bed itself could be formed from concrete itself or wood or a plastics material which could be a single polymer or a copolymer. However preferably, the bed is formed from a metal. This could . be ; steel. The metal could of course be an appropriate metal alloy.

More preferably, the metal is ferromagnetic.

The formwork can be constructed from timber, laminated veneer lumber (LVL) or other materials conventionally known to a person skilled in the art, however, preferably, the formwork is formed from metal. Preferably the metal is aluminium. This may be extruded and it may be hollow to make it easier to carry.

If the formwork is formed from a combination of metal and LVL, then this type of formwork is likely to form a door or window frame for the concrete panel that is being constructed. As such, this type of formwork is likely to have 45 degree cuts at least at one end to enable the frame to be constructed. Should special orders be required where for example octagonal frames are required, these pieces of LVL and formwork can be cut to the appropriate angles.

More preferably, the metal that forms the formwork is not identical to the metal used in the construction of the transportable casting bed. Tf steel is used for the bed, aluminium which is far lighter could be used for the formwork. The formwork could be diamagnetic or paramagnetic

and/or may be so sized and shaped as to enable an appropriate number of (usually four) pieces of formwork to be assembled into a perimeter shape that defines a hollow oblong and may be provided with adaptors to enable (or so adapted as to be able to receive) one or more of the clamping members.

Preferably, there are two types of formwork to transportable casting bed clamping members. This has the advantage that formwork that is not adjacent an edge of the bed could still be maintained in place if for example a magnetic clamping member were used if the bed was made from a ferromagnetic material.

More preferably, one type is magnetic or electromagnetic. This has the advantage that it enables a range of different types of formwork to transportable casting bed clamping members to be used, for example magnetic or electromagnetic ones as well as conventional non magnetic ones, for example clamps, in particular "G" clamps..

Preferably, the transportable casting bed is so sized and shaped as to be able to produce a mould capable of forming a concrete slab of at least 3 metres by 12 metres.

Although the height of 3 metres is likely to remain fixed, more preferably, the length of the mould may be varied by the provision of appropriately adapted (shortened or lengthened) or through the addition of further pieces of formwork and the addition of further casting beds .

As such, lengths of concrete formed may vary in the range of 4m to 36m, more preferably, the length is in the range of 4m to 12 m.

The invention includes within its scope apparatus substantially as herein described with reference to and/or as illustrated in any appropriate selection or combination of the accompanying drawings.

The invention further includes within its scope a concrete slab or tilt slab formed from the apparatus specified herein.

According to a third aspect of the present invention there is provided a magnetic or electromagnetic formwork to transportable casting bed clamping member adapted for use with a transportable casting bed as specified herein.

The clamping member may be an integral unit however preferably, the clamping member is provided with a demountable attachment adapted in use to engage with a piece of formwork of the type specified herein to assist in clamping the formwork to the bed.

More preferably, the attachment is slidable within a guide to enable the reach of the clamping member to be extended.

The invention includes within its scope a magnetic or electromagnetic formwork to transportable casting bed clamping member substantially as herein described with reference to and/or as illustrated in any appropriate selection or combination of the accompanying drawings.

The invention further includes within its scope apparatus for forming a concrete slab for use in the construction or- the tilt slab industry incorporating a magnetic or electromagnetic- formwork to transportable casting bed clamping member as specified herein.

According to a fourth aspect of the present invention there is provided formwork provided with one or more formwork to transportable casting bed clamping member receiving members that are so sized shaped and located on the formwork as to enable the formwork to be fitted to a transportable casting bed of the type specified herein in one of two useable opposing positions.

Preferably these members are in the form of channels.

These channels could be simply squared off channels as shown in figures 2, 5, 7 & 8. However, it has since been realised by the inventor that direct clamping onto a flat surface such as the base of such a channel, although generally effective at keeping the piece of formwork in place is not the best way of keeping such a piece of formwork in place as there is still a tendency for the formwork to move laterally if accidentally kicked by a workman. Thus it is not ideal to rely on mere pressure and friction of a small contact area of a clamping member acting on a piece of formwork to keep the formwork in place once the clamp has been tightened. It would be far

better if the channel contact area of the clamp was anything other than a substantially flat surface where the only force acting on the surface is at 90 degrees to any potential lateral movement. Far better then if the channel were "U", "V" "W" or any other appropriate shape to enable a complementary clamping surface to engage and lock down the formwork to the casting bed thus providing additional forces to prevent unintended lateral movement of the formwork.

More preferably therefore, these channels are provided with a locking guide and the clamping members are provided with a complementary locking guide engaging surface.

Yet more preferably still, said locking guide is a substantially curved "U" shaped channel.

Although each member may be formed from a plurality of channels, more preferably, each member is formed from one continuous channel that runs the length of the formwork.

The invention includes within its scope formwork substantially as herein described witii reference to and/or as illustrated in any appropriate selection or combination of the accompanying drawings. - . .. .. ..

The invention further includes within its scope apparatus for forming a concrete slab for use in the construction or the tilt slab industry incorporating formwork as specified herein.

According to a fifth aspect of the present invention there is provided a formwork extender adapted in use to extend the working length of a piece of formwork.

Preferably, the extender is adapted to engage with or be so positionable adjacent a piece of formwork as to present a useable arrangement of the two for the purpose of forming a concrete slab in a mold.

Both ends of the extender could be so sized and shaped as to engage with or be so positionable adjacent a piece of formwork as to present a useable arrangement of the two for the purpose of forming a concrete slab in a mold, however, preferably, only one end of the extender is so sized and shaped as to engage with or be so positionable adjacent a piece of formwork as to present a useable arrangement of the two for the purpose of forming a concrete slab in a mold.

Preferably the extender is so adapted as to slidably engage with one end of a complementary piece of formwork.

More preferably, the extender is adapted to slidably engage within one end of a complementary piece of formwork.

The working surface provided by the extender (and by worldng surface we intend to include at least those surfaces that are intended to come into contact with a cementitious concrete forming slurry) need not necessarily be substantially flush with the existing worldng surface of the formwork. In other words, if for some reason, the shape of the concrete slab to be formed needs to be provided with an altered topography in a particular area, use of such an extender may provide the solution.

However, preferably the worldng surface of the extender is substantially flush with the worldng surface of the formwork that it is adapted to engage with or be so positionable adjacent once in use, . . . _ _

Although the formwork could be formed from natural rubber or expanded plastics foam material, preferably the formwork extender is formed from plastics material for example polypropylene, polyethylene or suitable copolymers known to the person skilled in the art. Such an arrangement allows it to be cut/mitred easily (and usually 'on site') without the need to cut the formwork itself, reducing the need for the number of extrusions of formwork required and enabling those that are being used to be reused.

The invention includes within its scope a formwork extender substantially as herein described with reference to any appropriate selection or combination of the accompanying drawings.

Of course an existing floor of a building that is the subject of the construction on the building site could be used as a casting bed however, for the avoidance of doubt, such floors, once "down" are not normally intended to be transportable.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiment of the invention will now be more particularly described, by way of example only, with reference to the accompanying drawings in which;

Figure 1 illustrates an isometric view of a casting bed of the present invention.

Figure 2 illustrates a different isometric view of the casting bed illustrated in figure 1

Figure 3 illustrates isometric, side, plan and end views of a convention electromagnetic clamp known as Standard Pro Box (SPB).

Figure 4 illustrates an end view of a modified SPB for use with the present invention.

Figure 5 illustrates an isometric close up view of a clamp holding part of a formwork to the casting bed illustrated in figures 1 & 2 in place.

Figure 6 illustrates an isometric view of a plurality of reinforcing rods sat within the casting bed of the previous figures.

Figure 7 illustrates a further isometric view of the casting bed illustrated in the previous figures.

Figure 8 illustrates ^" an isometric blown up view of the formwork used around the periphery of the embodiment illustrated in figures 1, 2, 5, 6 Sc I

Figure 9 illustrates end, isometric and side views of a formwork extender that can be used to extend the length of an existing piece of formwork (see figure 13) of the present invention.

Figure 10 illustrates an isometric and side view of another type of formwork extender that can be used to extend the length of an existing piece of formwork (see figure 13) of the present invention.

Figure 11 illustrates an isometric view of a telescopically extendable clamp that can be used to hold part of a formwork to the casting bed illustrated in figures 1 & 2 in place.

Figure 12 illustrates isometric and sides views of a plurality of pieces of formworlc adapted to receive members (not illustrated) usually in the form of timber or laminated veneer timber.

Figure 13 illustrates cross sectional views of two other types of formworlc.

Figure 14 illustrates an isometric view of another type of formworlc suitable for 'use with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Figure 1 shows a plurality of transportable casting beds offloaded from a flat bed trailer and set up end to end ready for use on a building site. Each of the beds is generally referenced 1.

The length of the overall bed shown in figure 1 is approximately 36 metres and is produced by placing three substantially 12 metre bed sections end to end. Of course, the individual 12m beds 1 could be placed in different configurations to- suit the space available in any particular construction site or precast yard. The width of each of the 12m beds 1 that form the overall bed is approximately 3rn.

Each bed 1 comprises a substantially flat elongate steel base 2 of substantially uniform thickness that is provided with a peripheral projection of uniform dimensions that is flush with and projects from the upper (in use) and lower surfaces of the base 2 in the bed's normal attitude of operation.

Hollow extruded reinforced aluminium formworlc 3 in the form of straight elongate strips, (two short strips and several long strips) are connected together to form a rectangular frame on the upper peripheral surface of the base of the overall bed formed and shown in figure 1 to form a mould. The frame is held in place by a plurality of adjustable "G" clamps 4 located adjacent an external face of each piece of formworlc 3. The mould is provided with a grid 5 of steel reinforcing rods set at a height substantially midway between the top and bottom of the height of the formworlc 3.

The entire length of the top of the external face of each piece of formwork 3 is provided with an integrally formed "squared off' channel that is generated from a uniform strip of the formwork 3 that is flush with and projects from the top face of formworlc 3 and which is provided with a 90 degree fold about a line parallel with the longitudinal axis of the piece of formwork 3 to form

a lip 8. A mutually opposing but otherwise identical channel is also located along the entire length of the bottom external face of the formwork 3 thus one side of the formwork 3 may be considered to be a "squared off "C" shape.

As each channel is identical, each piece of formwork 3 can be placed onto the bed 1 in the manner shown in the figures or indeed the other way up.

hi either event, the lower surface of one channel is substantially contiguous with the upper surface of the base 2 (or the overall base as shown in figure 1), when a piece of formwork 3 is placed onto the bed 1.

Each lip 8 is of uniform height and runs parallel with the surface of the external face of the formwork 3, thus when a piece of formwork 4 is correctly placed onto the bed 1, the external face of the formwork 3 has a "u" and "n" shaped channel when viewed from one end of (or in an appropriate sectional view of) the formwork 3.

From figure 2, it can be seen that additional pieces of formwork 3 substantially identical in length to the short strips of formwork 3 mentioned hereinabove are placed on the upper surface of the base 2 to span the distance separating the internal surfaces of opposing long strips ^" of formwork 3 to divide the bed 1 into separate rectangular compartments 15 that each measure substantially 4m x 3m.

Clearly, clamps 4 cannot be used to secure the formwork 3 that is used to divide up the mould into compartments 15. However a modified magnetic SPB (Standard Pro Box) used in the tilt slab industry (see figures 3 & 4) and sold under the Trade Mark "RATEC" can be.

It can be modified to accept a "T" shaped folded plate of metal, which when fitted to the SPB forms a squared off "n" shaped channel (in the SPBs intended attitude of operation), one side of the "n" being formed from one side of the SPB.

From figure 13, we see an alternative type of extruded aluminium formwork in cross section generally referenced 400. The formwork 400 is provided with a pair of reinforcing struts 401 that are both parallel with the base and top of the formwork 400, the spacing of each strut 401 being substantially the same from respective ends of the formwork 400. The base and top of the formwork 400 is provided with a curved "U" or "C" shaped channel instead of the squared off

Hp 8, (as shown more clearly in figure 8) to enable clamp 200 (infra) to lock the formwork 400 into place in the manner described herein below.

Struts 401 act as shelves or guide members for cast aluminium or plastics material extension formwork generally referenced 500 in figure 9. The formwork extender 500 can be slotted into the ends of formwork 400 to extend the length of such formwork, the slots 501 mating with the struts 401. The free ends of the formwork extender 500 once fitted to the formwork 400 are appropriately recessed to enable the formwork 500 to lie flush against the shims or fillets 10 of other formwork (3,400) placed ninety degrees thereto to enable a substantially 'concrete forming composition fluid tight' seal to be formed. Such formwork extender if made from plastics material may be cut or mitred easily saving costly aluminium formwork from being destroyed. Face 506 which includes the shims may be considered to be the working face of the extension formwork 500 and when it is slotted into formwork 400, this surface 506 is substantially flush with the corresponding working surface of the formwork 400.

Whereas the formwork extender shown in figure 9 may be considered to be male to female, formwork extender, the formwork extender shown in figure 10 and generally referenced 600 and having a working surface of 601 is designed to be a female to male to female formwork extender. Such a formwork extender 600 will enable two lengths of formwork 400 to be linked together.

Turning to figure 5, this shows inter alia a front face 9 of the clamp 4 (which is essentially a planar rectangular plate), the lower shortest edge of which in use, is designed to sit within a channel generated by a lip 8.

The "G"~type body of the clamp 4 overlies the upper and lower surfaces of the upper peripheral projection of the bed 1, whilst a screw threaded adjustment mechanism 6 located within the body of the "G" (and which is adapted to contact the edge face defining the thickness of the peripheral projection once the clamp 4 is secured into place by the spindle 7) is used to align each piece of formwork with respect to the overall bed correctly.

From figure 5, a downwardly projecting lip 9 can be seen which is used to "bite" over the lip 8 and sit in the "u" shaped channel created by lip 8 to "lock down" the form work 3 to the base 2.

SPBs are also fitted to the channel in the formwork 3 that are used to divide up the mould into compartments 15 by overlying the channel generated by the "n" shape over the lip 8 and subsequently activating the magnetic clamp.

Figure 9 shows a different type of "G" clamp generally referenced 200.It has the same basic components shown for G clamp 4, however, in clamp 200, the projecting lip 9 is operatively linked to a slidable piece of rectangular tubing, the arrangement being such that the lip 9 remains substantially parallel with the front face of the clamp 200 as the lip 9 is moved along the entire path of available extension which ultimately is dictated by the length of the slidable tubing.

In figure 6, greater detail of the grid 5 is shown. The grid 5 comprises a plurality of elongate linear rods of different thickness. The thinner rods 13 are arranged in an array and sit on a plurality of substantially randomly spaced apart stools 11 that are approximately half the height of the formwork 3.

The thicker rods 12 are not arranged in an array but instead are arranged in parallel and run the length of each compartment 15 and overlie the thinner rods 12. The rods 12 & 13 are also locked together and to each other by a series of wire ties 16 substantially randomly located about the array.

Each piece of formwork 3 is provided with opposing fillets or shims 10 that runs the length of the top and bottom of the interior face in a continuous fashion.

Figure 12 shows end and isometric views of another type of formwork generally referenced 100. This type of formwork is made from aluminium and may be considered to comprise an elongate substantially "squared off' "U" or "C" shaped channel 101 that possesses a flat exterior base. One exterior side of the channel 101 is provided with a shim 10 substantially identical to the shim 10 of the other pieces of formwork associated with the present invention whilst the opposing exterior side 102 of which is parallel (and of substantially uniform thickness) with the interior wall of the channel 101.

The height of both sides 10,102 of the formwork 100 is substantially the same, the top of the side piece 102 being provided with a conventional curved "U" or "C" shaped channel 103 running along its entire length to enable a clamp (SPB or G) provided with an appropriately sized and complementary male lip 9 to mate with and otherwise sit in the "U" or "C" shaped

Z2006/000260

- 14 - channel 103 to "lock down" the formwork 100 to the base 2, this form of positive mating will minimise or otherwise prevent lateral movement of the formwork 100. Such movement is a possibility when using formwork 3, if a workman accidentally Icicles the formwork 3 or it shifts when concrete is being poured in despite being clamped down "tightly". Such a situation is far less likely to occur with any formwork having the "U" or "C" shaped channel 103 as shown in figure 12.

Figure 14 may be considered to be another type of formwork generally referenced 700 which can also be considered to be another type of formwork extender. If used as formwork, appropriate clamps of the type described herein can be used to either sit in the squared off channel 702 or sit within the curved channel 703 to fix the formwork 700 to a casting bed.

If used as formwork extender surface 701 can be used to butt up against complementary surface 701 on formwork 700. Once clamped into place in the manner described previously, the length of the formwork 700 can be extended. Alternatively, clamps can be used in channel 703 and LVL timber of the appropriate dimensions can be placed in channel 702.

With clamp 200, formwork (3, 100, 400) instead of having to be placed adjacent the peripheral edge of the bed 1 to enable it to be clamped down, can instead be placed at any point on the bed 1 which is within reach of the slidable extension of the clamp 200, the main body of the clamp 200 itself, still embracing the peripheral edge of the bed 1.

As can be seen from figure 12, at least one end of the formwork 100 is finished with a 45 degree cut enabling two similar pieces of formwork 100 to be linked together to form a 90 degree fold

The end faces of the formwork 3 possess bevelled shims and lips 8 such that the interior face of one piece of formwork 3 can lie flush against the end face of another piece of formwork 3 to ensure that once the frame of formwork 3 is formed, the mould is to all intents and purposes fluid tight, when we are referring to a concrete forming composition that is 'fluid' when it is poured into the mould.

Fig 13 also shows in cross section another type of formwork provided with a housing to enable an electromagnetic clamp 601 to be slid within it to clamp the formwork 600 to the bed 1.

In use, a kit of parts is supplied to a building site. The kit in the main, comprises one or more beds 1 which is/are first transported to the location by flat bed trailer (not illustrated) where concrete slabs are to be formed and erected.

The or each bed 1 is then offloaded from the flat bed and set up on the ground and levelled if required by a number of wooden shims. The rest of the kit is also off loaded from the trailer and used in the manner about to be described. The formworlc 3 is located on the upper surface of the base 2 of the bed once formed about the perimeter of the bed 1 to form a 'concrete forming composition fluid- tight' mould of the desired dimensions.

The clamps 4 in sufficient number and the adjustment mechanism 6 ensure that the location of the peripheral formworlc on the bed is extremely accurate. The adjustment mechanism (in tandem with the adjustment of the spindle 7) by moving against the edge face of the peripheral lip of the bed 1, being used to subtly pull or push the channel clamp 4 trapped formwork 3 into the correct location.

Clearly as the SPBs do not have any means of fine adjustment, these therefore can only be activated (or magnetised) once it is known that the compartment forming formwork 3 has been very accurately located.

If window frames or doors are required within the finished a compartment or on the bed 1 generally, formwork 100 is placed where it is needed to form the window or door frame and then laminated veneer timber (LVL) (not illustrated) designed to sit in the channel 101 created by the formwork 100 is placed therein and topped off by a similar but inverted piece of formwork 100 such that the shims 10 are on the same side. The LVL is so sized and shaped as to a) be a tight fit in the channel 101 and such that the top surface of the upper piece of form work 100 is substantially flush with the top surfaces of other pieces of formwork 3 within the mould.

Stools 11 are added to the mould and rods 13 are then sat on the stools 11, arranged in an array and wire ties 16 are used to link the rods 13 together.

Subsequently, rods 12 arranged in parallel are wire tied to rods 12. Concrete releasing fluid is then added to the mould along with recess formers and lifting eyes (as described in WO 03/021059A1, the relevant portions of which are imported by reference into this specification)

in appropriate numbers before a concrete forming composition is then guided/poured into the mould and allowed to set.

Once this has happened, the formwork 3 is removed and the concrete panel is made ready to be deployed wherever it is needed. The formed bed is then cleaned down and made ready to cast another concrete panel in the manner previously described until all of the required panels have been formed. At which point the kit that is left is removed from the site by loading it back onto the flat bed and is ready for transport to another location.

For shorter walls, only one bed or two beds 1 need be used.

Throughout the description and claims of this specification the word "comprise" and variations of that word, such as "comprises" and "comprising", are not intended to exclude other additives, compartments, integers or steps.

In addition, throughout this specification, the use of the term "integral" is intended to cover not only something which is formed from the outset as one single-entity component, but also anything which, whilst being assembled from a plurality of initially disparately produced integers, ends up as one overall and normally non dismantleable structure.

The invention also consists in the parts, elements and features referred to or indicated herein, individually, collectively or in combination. Also, where elements or features are mentioned herein and 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.

Clearly, the formwork and associated articles need not necessarily be used solely with a transportable casting bed of the present invention, they may be used with conventional casting beds as well.

Those skilled in the art to which the invention relates will see many variations not specifically mentioned herein which still come within the scope of the consistory clauses herein above.