FIELD OF THE INVENTION

This invention relates to shuttering and more specifically, but not exclusively, to control joint shuttering, expansion joint shuttering and crack inducement shuttering for a concrete slab or screed.

BACKGROUND TO THE INVENTION

Concrete slabs and screeds expand and contract over time as a result of changing ambient conditions. Control joints are usually cut into the slabs at regular intervals to allow cracking thereof to occur in a controlled fashion on or in such joints rather than arbitrarily.

It is often time consuming to cut control joints into the slabs and prefabricated sacrificial shuttering may be installed into a slab to provide control joints in the slab. One such prefabricated shuttering is described in European patent application number 10002170.8, published as EP 2 365 150 Al on 14 September 2011, entitled "Lost shuttering" ("the prior art"). The prior art discloses a shuttering formwork suitable for use as lost shuttering form work comprising an elongate body member including a base portion and a compression portion extending therefrom substantially perpendicular and presenting a free end that extends in the length direction of the elongate body member. The elongate body member comprises first and second sides, each comprising a compression portion side face and a base portion upper face. A strip element is releasable attachable to the free end of the compression portion. The compression portion side face and the base portion upper face of at least one side of the elongate body member are each a resiliently shuttering surface. The base portion is provided with apertures for receiving mortar material. A shuttering formwork fabricated from a plastics material and having a hollow structure.

A problem with the prior art is that different profiles of the formwork are needed for different thicknesses of slabs. A further problem with the prior art is that the profile of the shuttering makes it inefficient to stack for shipping.

OBJECT OF THE INVENTION

It is an object of this invention to provide shuttering which, at least partially overcomes some of the problems associated with the prior art.

SUMMARY OF THE INVENTION

In accordance with the invention there is provided shuttering comprising: an elongate shuttering member;

- a support member attachable to the elongate shuttering member to support the shuttering member in a desired position. The shuttering member and the support member have complementary shaped attachment means. The attachment means are attachable in a snap fit manner.

The attachment means on the shuttering member is elongate and extends along the length of the shuttering member on at least one major side thereof. The elongate attachment means of the shuttering member is an indentation; alternatively, a protrusion.

The shuttering member is an elongate extrusion having two major opposing sides. Elongate attachment means of the shuttering member are located on both major opposing sides.

In one embodiment, an operatively underside of the shuttering member terminates in a foot formation. The foot formation may be tapered. The foot formation may terminate in a sharp edge or point or may terminate in a radius.

The foot formation has a reduced or reducing width. An upper end of the shuttering member includes strip receiving formations for removable receiving an elongate strip.

The elongate strip has complimentary receiving formations.

The complimentary strip and shuttering member receiving formations are snap fit formations.

The support member, when attached to the shuttering member, supports the shuttering member in an upright position so that its major opposing sides are substantially vertical; alternatively, the support member supports the shuttering member at an angle to the horizontal.

The support member has a foot formation that is tapered or that terminates at its operatively lower end in sharp edges, sharp points or a radius.

The support member has a securing aperture for securing it in position.

The support member has side receiving formations for receiving complimentary side receiving formations of an adjacent support.

There is also provided for an elongate profile to be attachable to one side of the shuttering member. The profile has complimentary attachment means and is attachable to the attachment means on at least one major opposing side of the shuttering member. The support member is in the shape of a triangular prism.

The support member receiving formations may be protrusions protruding from one side, and holes on the other side.

The holes and protrusions are complementarily shaped.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention is described below, by way of example only, and with reference to the drawings in which:

Figure 1 is a schematic perspective view of a shuttering member;

Figure 2 is a schematic perspective view of a support member from one angle;

Figure 3 is a schematic perspective view of a strip member; Figure 4 is a schematic view of shuttering including two shuttering members located end to end and associated support members and a strip members; Figure 5 is a cross-sectional view of a shuttering with a profile strip attached thereto;

Figure 6 is a schematic perspective view of a support member shown from a second angle; and

Figure 7 is a cross-sectional view of a second embodiment of shuttering.

DETAILED DESCRIPTION OF THE DRAWINGS

With reference to figures 1 to 6, in which like features are indicated by like numerals, shuttering is generally indicated by reference numeral 1.

The shuttering 1 includes an elongate shuttering member 2, and a support member 3. The shuttering member 2 includes attachment means in the form of outwardly opposing engagement formations 4. These formations extend along the length of two major opposing sides of the shuttering member. The support member 3 includes attachment means in the form of inwardly opposing engagement formations 5a and 5b (5). The outwardly opposing formations 4 and inwardly opposing formations 5 form a snap fit configuration wherein the support member 3 is attached to the shuttering member 2.

The shuttering member includes attachment means for attaching a removable strip 6 at the upper end thereof. The attachment means is in the form of inwardly opposing protrusions 7. The lower end of the shuttering member includes a foot formation 8. The support member 3 includes a base 9 with tapered protrusions 10 extending downward from the base.

The foot formation 8 is tapered, extends along at least part of the length of the shuttering member and terminates in a sharp edge. Alternatively, it can terminate in sharp points or a radius.

The support member has a triangular cross-sectional profile including an internal support member 11. The support member has protrusions 12 protruding from one side, and holes 13 on the other side. The holes 13 and protrusions 12 are complementarily shaped such that the protrusions 12 of one support member may be inserted into the holes of another to extend the length of the support member 3. The positions of the protrusions 12 on one side of the support member 3 correspond with the positions of holes 13 on another member, when the stabilising members 3 are placed side by side. The base has a recess (marked a in figure 2) on a side of the base 9 the support member 3 so that a stake or nail may be driven through the base 9 to fix the support member 3 to the ground surface or formwork shuttering system. The support member 3 further has two holes (marked b in figure 2) at the outer end of the support member 3 so that stakes or nails may be driven through the holes to fix the support member 3 to the ground surface or formwork shuttering system.

The support member also has a foot formation that terminates in lower sharp edges. Instead of sharp edges, the foot formation could end in sharp points or radiuses. In use, shuttering 1 will be assembled on site where a concrete slab is to be cast. A shuttering member of appropriate height is selected. A number of stabilising members 3 are attached to the shuttering members at appropriate positions. For example, where the shuttering is positioned between two blocks of the slab, at least 4 stabilising members will be attached to the shuttering member. In this example, one shuttering member is attached to each corner of the shuttering member (as shown in figure 6). With the stabilising members attached to the shuttering members in this arrangement, the shuttering member can stand on its own and may be attached to a similarly assembled shuttering member (as shown in figure 5). Where the shuttering needs to form a corner the stabilising members may be staggered or excluded to prevent overlap of stabilising members.

A profile strip 20, which is an elongate strip (an end-on cross-sectional view of which is shown in figure 5) is attachable to the shuttering member. This profile will then be cast into the concrete slab in use. The concrete will be poured and the shuttering member will support the concrete and prevent it from flowing past the shuttering member. The shuttering member thus forms an outer end of a concrete slab or slab section. Concrete may of course be poured on both sides of the shuttering member, even over support members.

The shuttering member may also be supported at an angel with a support member shown in Figure 7. The tapered portion 8, along with tapered protrusions 10 decrease the contact area of the shuttering when the floor is cast. This is important, especially where second and subsequent stories' floors are cast to decrease the visibility of the shuttering from stories below the slab.

It is further envisaged that the invention will provide control joint shuttering for inducing controlled cracking which may be used to cast floors of different thicknesses and is easily assembled.

It is envisaged that the invention will provide control joint shuttering which is usable for casting concrete slabs of different thicknesses and is efficiently stackable for transportation and packaging.

The invention is not limited to the precise details as described herein, for example instead of having protrusions on a removable support member to facilitate wedging thereof between the base and the shuttering member, the removable support member may be wedged in place using its ends. Further, instead of the base having curved supports at the raised portion and curved outer ends, any other complementary shape may be used to facilitate stacking of the bases. 10