AUSTRALIA ORIGINAL COMPLETE SPECIFICATION INNOVATION PATENT Invention Title: Jointing System Name of Applicant: Sandie Holdings Pty Ltd Actual Inventor: Shane Gherbaz Address for service: WRAYS Ground Floor, 56 Ord Street West Perth WA 6005 Attorney code: WR The following statement is a full description of this invention, including the best method of performing it known to me:- JOINTING SYSTEM TECHNICAL FIELD [0001] The present invention generally relates to a joining element. BACKGROUND ART [0002] It is usual to provide expansion/contraction joints in cast concrete such as driveways, cycle paths and foot paths to accommodate thermal contraction and expansion, and thus minimise cracking. [0003] A system for forming expansion/contraction joints in cast concrete is disclosed in Australian Patent No. 671528. This patent is directed to providing a jointing element for the formation of an expansion/contraction joint that includes a base portion for resting on the ground and intermediate sections offset from a vertical upper portion. Additionally supports can be placed against the jointing element on the side opposite the concrete pour to keep the joint in place and then subsequently removed. [0004] In practice, after this jointing element is placed in position, during casting it is possible for the intermediate sections to bow. Additionally, after casting there is the need of additional labour to remove the supports in place prior to pouring an adjoining slab. [0005] The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application. SUMMARY OF INVENTION [0006] The present invention seeks to provide a jointing element which ameliorates, mitigates or overcomes, at least one disadvantage of the prior art, or which will at least provide the public with a practical choice. [0007] The present invention provides a jointing element for the formation of a joint in cast concrete, comprising a base portion for engaging a foundation surface onto which the concrete is cast, an upper portion and an intermediate portion between the base portion and the upper portion, the intermediate portion comprising an offset section offset from the upper portion and extending transversely of the upper portion; wherein the upper portion is extended from the base portion and wherein the intermediate portion comprises a flange extending from the offset section transversely to the extension of the upper portion from the base portion. [0008] There may be a junction between the upper portion and intermediate portion that may comprise an additional flange extending laterally to the extension of the upper portion from the base portion. [0009] The jointing element may be adapted to engage a support element, wherein the support element is adapted to fix to the foundation surface. [0010] The support element may be adapted to engage with the side of the jointing element with the flange. [0011] The base portion may be adapted to rest on the foundation surface and extends transversely of and beyond the upper portion to present a relatively broad surface for contact with the ground or other foundation surface. [0012] An aperture adapted to receive the support element may be located in the flange. [0013] The additional flange may be adapted to rest against the support element in use. [0014] The present invention also provides a jointing system for creating a joint between concrete slabs wherein the jointing element is engaged with a foundation surface and concrete is poured to either side of the jointing element. [0015] Concrete may be poured to either side of the jointing element becoming interlocked together at the jointing element. BRIEF DESCRIPTION OF THE DRAWINGS [0016] Further features of the present invention are more fully described in the following description of non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. The description will be made with reference to the accompanying drawings in which: Figure 1 is a side view of an embodiment of a jointing element according to the present invention; Figure 2 is a perspective view of the jointing element of Figure 1; Figure 3 is a perspective view of the jointing element of Figure 1 with apertures in place; Figure 4 is side view of the jointing element of Figure 1 in place with support elements ready for a concrete pour; Figure 5 is a side view of the jointing element of Figure 1 in place with concrete poured to one side; Figure 6 is a side view of the jointing element of Figure 1 in place with concrete poured on both sides. [0017] In the drawings like structures are referred to by like numerals throughout the several views. The drawings shown are not necessarily to scale, with emphasis instead generally being placed upon illustrating the principles of the present invention. DESCRIPTION OF EMBODIMENTS [0018] Referring to Figures 1 to 6, the embodiment of the jointing element 1 according to the invention can act as an expansion/contraction joint between slabs of concrete. The jointing element 1 comprises a body 10 having a base portion 11, an upper portion 13 extended upwardly away from the base portion and an intermediate portion 15 between the base portion and the upper portion. Junctions are formed where the intermediate portion 15 meets the upper portion 13 and base portion 11. The upper portion 13 is upright in use, and includes a top edge 17. The base portion 11 is configured as a bottom flange extending to one side of the upper portion 13 and terminating at an outer edge 19. [0019] The intermediate portion 15 comprises first, second, and third sections 21, 22 and 23. The first and second sections 21, 22 are positioned in a spaced apart relationship and extend laterally to one side of the upper portion 13. In the arrangement shown, the first and second sections 21, 22 extend to the opposed side of the upper portion with respect to the bottom flange defined by the base portion 11. The third section 23 is disposed between the first and second sections 21, and extends laterally to the other side of the upper portion 13; that is, the third section 23 is in opposed relation to the first and second sections 21, 22 and extends to the same side of the upper portion as does the bottom flange defined by the base portion 11. [0020] The first, second and third sections 21, 22 and 23 are integral one with another and cooperate to define a corrugated formation which in this embodiment is sinusoidal. The corrugated formation serves to interlock the sections of the concrete slab on opposed sides of the expansion/contraction joint. The interlocking arrangement is such that the joint can be separated in the event that it is necessary to repair a damaged section of the concrete slab. [0021] The body 10 further comprises an upper flange 31 and a lower flange 33, each extending to the same side of the upper portion as does the bottom flange defined by the base portion 11. The upper flange 31 is provided at the junction between the intermediate portion 15 and upper portion 13, and terminates at outer edge 32. The lower flange 33 is provided along the length of the third section 23 and terminates at outer edge 34. In the arrangement illustrated, the lower flange 33 is located at the midpoint of the third section 23. [0022] Alternatively to the above arrangement, instead of flanges 31 and 33 being provided along the length of the third section 23, flanges can be provided along first and second sections 21, 22. When flanges are provided along first and second sections 21, 22, the flanges extend to the opposite side to the bottom flange defined by the base portion 11 in an opposed relationship. [0023] The flanges 31, 33, in conjunction with the bottom flange defined by the base portion 11, facilitate installation of the jointing element 1 in a manner which will be described. Further, the flanges 31, 33 in conjunction with the corrugated formation of the intermediate portion 15 serve to reinforce the jointing element 1 so that during pouring of concrete the jointing element 1 is less likely to bow due to the force exerted on it from the poured concrete. This reinforcing aids the jointing element maintain its shape during concrete pouring. [0024] The body 10 of the jointing element can be formed of a plastic material such as PVC, polypropylene, a composite material, metal, or a variety of other material readily recognised by the skilled addressee. The jointing element 1 can be formed through extrusion or a variety of other moulding techniques known by the skilled addressee.
[0025] The base portion 11 extends transversely of the upper portion 13 to one side thereof, terminating at the free edge 19. The base portion 11 presents a broad surface 20 for resting on a foundation surface 55 on which the concrete slab is cast. Typically, the foundation surface 55 comprises ground which has been prepared to receive the cast concrete. [0026] The jointing element 1 is supplied as a length that can be cut to fit the requirements of a particular job. The jointing element 1 is positioned between formwork which defines the sides of a slab to be cast and is located such that the free edge 19 of the base portion 11 faces the section of the slab to be cast and the top edge 17 is at the level of the upper face of the slab. The top edge 17 can have a ribbed edge that protrudes on both sides of the upper portion 13 to prevent or at least inhibit the entry of foreign matter into the completed expansion/contraction joint. Alternatively the top edge 17 can be covered by a cap 77 that also serves to exclude foreign matter. To aid in the retention of a cap 77 on a top edge 17, the upper portion 13 can include protrusions 67 that engage with internal protrusions in the cap 77. [0027] The base face presented by the base portion 11 allows the jointing element 1 to sit firmly on the foundation surface 55. Once the jointing element 1 is in position, concrete can be poured into the form work and a vibrating screed can be used to vibrate and level the slab. The screed vibrates easily over the joint element 1. Once the concrete is poured, the concrete slab is trowelled and finished leaving the surface level and smooth, with no ridges at the expansion/contraction joint. It will be noted that the base portion 11 extends under the section of the slab being cast. [0028] The jointing element 1 provides a joint between sections of the slab which can accommodate thermal contraction and expansion to aid in minimising cracking. The corrugated formation serves to interlock neighbouring sections of the a slab at the expansion/contraction joint in a way which can accommodate normal loadings but which can also be separated to allow damaged sections of the slab to be repaired. [0029] Figures 2, 4, 5 and 6 illustrate where support elements 25, illustrated as pins, are used with this invention to anchor the jointing element 1 to the foundation surface 55 on which the concrete slab is to be cast and Figure 3 illustrates a jointing element that can receive the support elements 25. The flanges 31, 33 and the bottom flange defined by base portion 11 project to the side of the jointing element 1 in which concrete is to be poured. The flange 33 and the bottom flange defined by base portion 11 include apertures 41 to enable the support elements 25 to be driven through the jointing element into the foundation surface 55 on which the concrete slab is to be cast, effectively anchoring the jointing element 1 to the foundation surface 55. The edge 32 of the upper flange 31 does not include an aperture, instead abutting the support elements 25 to support the jointing element 1. The support elements 25 when fitted through the apertures 41 sit at a distance from the top edge 17 so that that the pins do not protrude from the concrete slab. [0030] The apertures 41 can be formed at the time the jointing elements are manufactured or can be formed on site. The holes can be cut, burned, punched or machined in other ways recognized by the skilled addressee. [0031] With the support elements 25 in place in the apertures 41, the jointing element 1 is further reinforced to resist bowing, maintain its shape and remain straight and upright during a concrete pour. The support elements 25 are located on the side of the jointing element 1 into which concrete is poured so that they remain within the slab when set. By having the support elements 25 within the concrete slab the need for labour to remove any conventional holding bars, clamps or backing boards is removed. If flanges 31, 32 are not use and instead flanges extends along first and second sections 21 and 22 are used as discussed above similar reinforcing of the jointing element 1 is achieved. [0032] When the jointing element 1 includes flanges, 11, 31, 32 in combination with the anchored support elements 25 it is kept rigid. [0033] Figure 5 illustrates the jointing element 1 with a supporting element 25 in place in the flange 33 and bottom flange defined by the base portion 11 after concrete has been poured to one side 40 of the jointing element 1. The force of the concrete pressing against the jointing element 1 is resisted by the flanges 31, 33, the flange defined by the base portion 11 and the support element 25 which keeps the jointing element in place during the pour. With the supporting element 25 in place, the second side 42 of the jointing element 1 is left open ready to receive a pour for a joining slab of concrete. [0034] Figure 6 illustrates the jointing element 1 in place with concrete poured to both sides 40 and 42 of it. In place between set concrete slabs the jointing element 1 is able to flex in response to the expansion/contraction of the slabs, aiding in reducing the likelihood of the slab cracking.
[0035] Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention. For example at least a portion of the flanges could extend transversely to the upper portion in the direction of the upper portions extension from the base portion 11. Additionally, the base portion, instead of extending to one side of the upper portion, could extend parallel to the upper portion 13, including stakes or spikes to be driven into the foundation surface. The present invention is not to be limited in scope by any of the specific embodiments described herein. These embodiments are intended for the purpose of exemplification only. Functionally equivalent products, formulations and methods are clearly within the scope of the invention as described herein. [0036] Reference to positional descriptions, such as lower and upper, are to be taken in context of the embodiments depicted in the figures, and are not to be taken as limiting the invention to the literal interpretation of the term but rather as would be understood by the skilled addressee. [0037] Throughout this specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.