COMPOSITE PANEL, CONNECTOR AND RELATED METHOD

Field of the Invention

The present invention generally relates to composite panels, to connectors for composite panels, and to sheets and methods of constructions for use in composite panel construction. The invention has been developed especially, but not exclusively for tilt-up wall panel construction, and is herein described in that context.

However it is to be appreciated that the invention is not limited to that use.

Background of the Invention

Known pre-cast concrete tilt-up wall panels are either cast on a building site or off-site and thereafter transported to the site. In either case, on the building site the panels are positioned or cast on an underlying support structure, typically a rebated concrete slab, to form the walls of the building. Thereafter, the roof of the building is constructed to complete the main structure of the building.

In International patent application WO2006/058390, the Applicant discloses a tilt-up wall panel that is in the form of composite structure having a profiled sheet and cementitious material cast on the sheet. Whilst such panels have substantial advantages there is a need to ensure that loading can be applied to the panels (for example when lifting the panels during installation) without damage to the panels.

Summary of Invention

According to a first aspect of the invention, there is provided a composite panel comprising a layer of

hardened settable material, at least one element bonded to and/or embedded in the settable material, and one or more connectors fixed to the at least one element, the or each connector comprises a coupling portion that is disposed at a surface of the panel and arranged to form one part of a load bearing coupling, wherein loading induced at the coupling is arranged to be transferred through the connector to the element.

In the specification, the term "composite" is used in a general sense to specify that the panel is made from separate elements without requiring a particular interrelationship between those elements. For example, whilst in one form the element (s) may act as tensile reinforcement in the settable material, the composite panel is not limited to such an arrangement.

In accordance with this aspect of the invention, the connector is arranged in use to be fixed to the element in the composite structure rather than being solely embedded in the partially or fully hardened material, as is the case in traditional concrete tilt up panels. This allows for loading across the resulting coupling to be transferred to the element which can be better placed to accommodate that loading particularly when it is in a direction that induces a pull out force on the connector as is the case when the coupling connector the panel to lifting equipment to tilt the panel up into place. This arrangement has particular application where the settable material may be of relatively low strength, such as low strength concrete, as the strength of connection can be greatly increased over what would otherwise been provided if the connector was merely embedded in the concrete layer. A further advantage is that the minimum pull out force for the element is able to be relatively easily calculated which allows the system to be inherently safer.

In an embodiment, the connector is at least partially- embedded in the settable material .

In one form, the at least one element is in the form of a sheet . However in another form, the element may be in the form of an elongate section, such as a channel section, rod, wire or mesh.

In one form, the at least one sheet element is profiled and comprises a pan and at least one stiffening formation upstanding from the pan, the stiffening formation being embedded within the settable material. In a particular arrangement, at least one of the connectors is fixed to the stiffening formation.

In one form, the at least one sheet element is disposed along one major surface of the composite panel. The element may be in form of a discrete member that is embedded or bonded to the panel surface. However, in a particular form the sheet element is one of a plurality of sheet elements that are interconnected in edge to edge relation so as to extend across at least the majority of that major surface. In a particular form of this latter arrangement the sheets form a deck on which the settable material is cast.

In one form, the coupling portion of the one or more connectors is exposed along an edge or side surface of the panel. In a particular embodiment of the connector, the coupling portion comprises a coupling body that extends to an edge or side of the panel, the body having a passage that incorporates an engaging formation, which in one form may be an internal thread.

In a particular form the settable material is cementitious . In one form the at least one element is formed of metal. In a particular arrangement, at least

one of the connectors is fixed to the element by one or more mechanical fasteners. In one arrangement the one or more mechanical fasteners extend through one or more preformed holes formed in the element.

The one or more connectors may be used in various ways. In one form, the connector (s) may be used as lifting points for the panel in say a tilt up panel arrangement . In another form, the connectors may be used to fasten the panel to a structure such as a floor slab and/or a roof truss. In another form, a plurality of connectors may be provided that are spaced apart . The connectors may be used to load the element (say by pre tensioning the element prior to casting of the material or to post tension that element) so as to prestress the resulting composite panel .

In a further form, the invention is directed to a connector for use in a composite panel according to any form described above.

According to a further aspect of the invention there is provided a connector for a composite panel of the type having a layer formed from a settable material and at least one element bonded to and/or embedded in the settable material, the connector comprising an attachment portion arranged to be fixed to one or more of the at least one element, and a coupling portion connected to, or integrally formed with, the attachment portion and arranged to form one part of a coupling arranged to accommodate loading.

In an embodiment, the attachment portion comprises a plate having one or more apertures therein arranged to receive respective mechanical fasteners to secure the connector to the element (s) .

In an embodiment, the coupling portion comprises a body incorporating one part of a threaded coupling. The coupling body may comprise a passage incorporating a female thread on an interior surface of the coupling body that defines the passage. The coupling body may be generally cylindrical and further comprises opposite first and second ends, the passage extending along the axis of the cylindrical body and opening to at least one of the first and second ends. In another form, the coupling comprises a body in the form of an elongate member, such as a steel flat bar or angle or combination thereof, that projects from the sheet.

In an embodiment, the connector is formed from a metal casting.

According to a further aspect there is provided the combination of a connector and element, the combination being arranged to be embedded in or bonded to a hardened settable material, the connector portion comprising a coupling portion arranged to form one part of a load bearing coupling, wherein loading induced at the coupling is arranged to be transferred through the connector to the element .

In an embodiment of the fourth aspect, the element forms part of a deck on which the settable material is arranged to be cast .

According to fifth aspect of the invention, there is provided a profiled panel member comprising a pan and at least one longitudinal stiffening formation projecting from the pan and extending between opposite ends of the panel, wherein the panel comprises one or more preformed holes along at least one edge margin of the panel .

In an embodiment, the one or more preformed holes are formed in the stiffening formation.

According to a sixth aspect of the invention there is provided metal decking comprising a plurality of panel members according to the fifth embodiment of the invention, the panels being arranged in a side by side relation.

In one form, the decking includes one or more connectors connected to respective ones of the panels by mechanical fasteners that extend through respective ones of the preformed holes .

In one form, any one or more of the combination, profiled panels, and/or deck according to the fourth, fifth or sixth aspects are provided as a kit of components, which is subsequently assembled, typically on site in the construction of a structure (such as a dwelling) or in an intermediate assembly facility.

According to a seventh aspect of the invention there is provided a method of fabricating a composite panel, the method comprising the steps of: providing a deck formed from at least one profiled panel member; fixing a connector to one or more of the at least one panel member; and casting a settable material layer onto the deck.

In an embodiment, the settable material is cementitious .

Brief Description of the Figures

In order to achieve a better understanding of the nature of the present invention embodiments will now be

described, by way of example only, with reference to the accompanying figures in which:

Fig. 1 is a perspective view of one embodiment of a metal decking according to the invention; Fig. 2 shows a side elevation view of an embodiment of a panel assembly according to the invention;

Fig. 3 shows a side elevation view of an embodiment of a panel assembly according to the invention;

Fig. 4 is a front elevational view of one embodiment of a connector according to the invention;

Fig. 5 is a side elevational view of the connector of Fig . 4 ;

Fig. 6 is a plan view of another embodiment of a connector according to the invention; Fig. 7 is an elevational view of the connector of Fig. 6;

Fig. 8 is an end view of the connector of Fig. 6;

Fig. 9 shows an embodiment of a connector according to the invention in one exemplary use,- and Fig. 10 shows a side elevation of an embodiment of a composite panel according to the invention.

Detailed Description of Embodiments

Turning firstly to Figs. 1 to 3, a panel assembly 10 is disclosed which is arranged to form part of a composite structure 50 (see Fig. 10) . The panel assembly includes a deck 12 and a peripheral edge 14 that extends around the deck and defines a cavity 17 which is arranged to receive a settable material 52. The settable material is typically cementitious (such as concrete) and the resulting composite structure 50 comprises the panel assembly 10 and the hardened layer 52 of the cementitious material. The components are intimately connected as is described in more detail below so that the panel assembly 10 provides reinforcing to the cementitious layer 52.

In the illustrated form, the resulting composite structure 50 utilising the panel assembly 10 is designed for tilt-up construction where the structure 50 forms a wall panel of a building. In a first stage of construction of the building the composite structure 50 is formed by casting of the cementitious layer 52 into the panel assembly 10 whilst it is laid out in a horizontal configuration. After curing of the cementitious layer, the panel 50 is then "tilted up" into a vertical orientation using lifting apparatus such as a crane. Typically one side 54 of the composite panel 50 which includes the exposed concrete face forms an external surface of the building whereas the other side 56 which incorporates the metal decking as an exposed face forms the internal surface of the wall. When the composite panel 50 is in its correct vertical orientation, the wall can then be fitted out by fixing various components to that composite structure such as internal battens, facing sheets (such as internal plasterboard sheeting) and window and door fittings.

The panel assembly 10 includes, in addition to the peripheral edge 14, one or more opening 18 and internal edge members 26 that surround the openings. The incorporation of the openings and internal edge members is designed to provide the window and door openings in the resulting composite panel 50 which in turn are arranged to receive the associated window and door fixing details. The panel assembly 10 is made up of multiple components which allow for flexibility in the dimensions of the panel assembly and the position and size of the openings thereby providing flexibility in the layout of the resulting panel 50.

The deck 12 of the panel assembly 10 is formed from a plurality of profiled sheets 30 arranged in side by side relationship to create at least the majority of the deck

12 of the panel assembly 10.

The profiled sheets 30 have an intermediate section 32 which in one form may include stiffening formations 34 that extend along the sheet. The profiled sheets 30 also include opposite ends 35 and longitudinally extending side margins 36 and 38 that are turned out of the intermediate section 32. The side margins 36, 38 are arranged to inter- engage with the opposite side margin of an adjacent profiled sheet 30 so that the decking 12 is continuous.

Furthermore, the side margins 36, 38 inter-engage so as to resist lateral expansion under loading of the panel which occurs on casting of the cementitious layer 52.

Typically, each of the side margins include a web 40 that extends from the intermediate section 32, a flange 42 that extends from a distal end of the web 40 and a lip return 44. One side margin 36 is nested in the other side margin 38 of an adjacent sheet with the respective flanges 42 and webs 40 in abutting relation.

The profiled sheets 30 are typically formed in standard widths are made from sheet steel that incorporates a corrosion metal coating. Example sheet steel is sold by the applicant under the trade name

ZINCALUME. The sheet material may be provided in coils so that the sheet is profiled in a continuous length and then cut to size to form individual profiled member sheets 30. In a particular form the profiling of the sheets is done by cold forming such as by passing the steel strip through one for more roll formers. In this arrangement the side margins 36, 38 and the stiffening formations 34 extend longitudinally in the direction of the steel strip.

Typically in use the resulting composite panel 50 when in its final orientation as a wall has a horizontal dimension which is longer than the height or vertical

dimension of the structure. As such, the panel assembly 10 (and resulting structure 50) have "short" sides 15 that are arranged to extend vertically, and the "long" sides 16 that extend horizontally. With the orientation, the individual profiled sheets 30 are orientated so that the side margins extend generally parallel to the short side 16. While the long side is usually of greater length than the short side, the panel assembly is not limited to that arrangement and as such the terms "long" and "short" are used for descriptive convenience and are not be construed to limiting the invention to particular dimensional relationships .

The peripheral edge 14 of the panel assembly 10 is typically formed from separate members, being in the illustrated form, short side edge members 60 which extend along the short side 15 of the panel and long side edge members 70 which extend along the long side 16.

The panel assembly also includes a plurality of connectors 100 which are disposed along the opposite long sides 16 of the assembly 10 and which are fixed to the deck 12. In the illustrated form, the connectors are fixed to overlapping side margins 36, 38 of interconnected sheets 30. In use the connectors are arranged to be largely embedded within the cementitious layer 52.

One embodiment of the connector 100 is shown in Figs. 4 and 5. The connector 100 has an attachment portion 102 arranged to be fixed to one or more sheets 30. The connector 100 also has a coupling portion 104 operationally coupled to the attachment portion 102 and arranged to form one part of a load bearing coupling. The coupling portion 102 is, in this embodiment integrally formed with the attachment portion 104, although the attachment 102 and coupling 104 portions may in some other embodiments be formed separately then fixed together by

welding or other suitable means, possibly with an intermediate portion between them. In this embodiment, the connector 100 is formed from a metal casting. The connector 100 is, in this embodiment, fabricated from steel, such as mild steel. Some embodiments of the connector 100, such as shown in Fig. 4, are advantageous because they are easy to manufacture or generally reduce the number of fabrication steps required. An integrally formed connector 100 is particularly strong as it has no fastening means, which may introduce weaknesses.

As shown in Fig. 5, the attachment portion 102 comprises a plate 106 having three apertures 108, 110 & 112 therein arranged to receive respective mechanical fasteners, such as a nut and bolt, rivet or metal tie, to secure the connector 100 to the sheets 30. Some embodiments have the advantage that the connector can be readily attached and then detached from the metal decking 12, without damage to the metal decking, particularly when a removable fastener is used. In some embodiments, however, the attachment portion 102 may be otherwise arranged to receive a fastener for fastening the panel attachment portion to the panel. In some embodiments, there are no apertures 108, 110 and 112. The attachment portion 104 may be welded, fixed with adhesive, nailed, fastened with self-drilling fasteners or otherwise connected to the sheets.

In the embodiment shown in Figs . 4 and 5 , the attachment portion 102 comprises an angle plate 140 having two mutually inclined elongate flat portions 136,138. The angle 140 may meet at an apex 142. The use of an angle 140 is advantageous in some embodiments because the angle 140 resists bending and twisting forces. Some embodiments have the additional advantage that the flat portions

136,138 are compatible with mounting to a web 40 of the decking 12 to which the angle 140 is mounted. The flat

portion 136 mounted on the web 40, for example, would assist in preventing the angle 140 twisting away from the web 40. Aligning the connector portion 104 with the angle 140 has the advantage of maximising a common length along which force can be transferred between the connector portion 102 and the angle 140 and thus results in a stronger connector 100.

In this embodiment, the coupling portion 104 comprises a body 124 incorporating one part of a threaded coupling 126. The coupling body 124 may comprise a passage 130 incorporating a female thread on an interior surface 128 of the coupling body 124 that defines the passage 130. The coupling body 124 may be generally cylindrical and comprise opposite first 132 and second ends 134. The passage 130 extends along the axis of the cylindrical body and opens at the first end 132, although in some other embodiments it may open at the second 134 or both ends 132,134. In this embodiment, the connector has an external surface 144 that is polygonal which is advantageous because it mates well with a tightener such as a spanner. It is to be appreciated that the coupling portion 104 may take other forms. For example the coupling portion may take the form of a lifting eyelet, a component for a bayonet coupling, the important aspect being that the resulting coupling needs to be able to accommodate significant load across the coupling.

The connector 100 provides one part of a load bearing coupling such as is required to connect the resultant composite panel 50 to the working end of a crane in a tilt-up panel construction. As mentioned above during construction composite panels are regularly manipulated by cranes or other types of panel lifters. Loading induced at the coupling is arranged to be transferred through the connector 100 to the sheets of the composite panel. Another advantage of some embodiments is that damage to a

composite panel is avoided during its lifting by using the connector 100 instead of an inappropriate direct connection of the panel to the working end.

In this embodiment, the connector 100 can also be used as a shear connection with another part or structure. As shown in Fig. 9, the connector 100 is able to connect a composite panel 94 with a top plate, beam or steel C section 90 (other examples of things) that runs perpendicular to the connector 100 and supports a roof truss 92. Whilst not shown, the connectors 100 located at the lower side 16 of the composite panel may be used to fix the panel to a floor slab. In this way, the connector 100 may be multipurpose, making the use of additional devices for other desired functions (for example, shear or top plate connections as well as crane connections for the panel) redundant which reduces costs and provides a more compact device. Thus a "universal connector' may be provided which is convenient.

Furthermore, when multiple connectors are used, those connectors may be used to load the resulting structure through the element (s) in which they are connected. For example, connectors are provided on the top and lower sides (as shown in Fig. 1) those connectors can be used to pre-tension the steel decking before casting (thereby allowing prestressing of the concrete when hardening by releasing that applied tension force on hardening of the cementitious layer) or to apply loading to the panel when installed.

Figures 6, 7 and 8 show different views of another embodiment of a connector 180 which is generally cylindrical. Similar components to the other embodiment 100 are similarly numbered. The cylinder may have any suitable cross-sectional shape, although circular and square cross-sections are advantageous for their ease to

machine and good mating ability with the sheets 30. Cylindrical embodiments are advantageously compact. Additionally, some generally cylindrical embodiments may have the advantage of requiring a minimum quantity of material and manufacturing steps which reduce the part, transport, and storage costs.

As shown in Figures 6 and 7, the connector 180 includes three apertures 182 arranged to receive respective mechanical fasteners such as nut and bolt, rivet or metal tie, to secure the connector 180 to the sheets 30. In some embodiments, however, the connector 180 may be otherwise arranged to receive a fastener for fastening the connector 180 to the panel 10 assembly. In some embodiments there are no apertures and the connector may be welded, adhered, nailed, fastened or otherwise connected to the sheets 30.

The connector 180 further comprises a body 194 incorporating one part of a threaded coupling 196. The body 184 includes a passage 188 incorporating a female thread on the interior surface of the passage 198. The body includes opposite first end 202 and second end 204. The passage 188 extends along the axis of the body and opens at second end 204, although in other embodiments it may be open at first end 202 or both ends.

The sheets 30 are profiled and each comprises a panel, such as 32, and at least one stiffening formation 40 upstanding or projecting from the panel 32. The stiffening formation 40 is, in this embodiment, in the form of a web 40 extending from opposite ends 33,34 of the panel 32. The panels, such as 32, comprise one or more preformed holes 190 along at least one edge margin, in

this case the webs 40, of the panel. The web 40 is in use in the resultant composite panel arranged to be at least partially embedded within the settable material (not shown) when the composite panel is completed. The connector 100 is fixed to the stiffening formation 40. In fact, the stiffening formation 40 is a pair of adjacent stiffening formations, one of the pair belonging to respective adjacent sheets 30. Mechanical fasteners (not illustrated) pass through the apertures 182 of the connecting portion 184 and apertures, such as 190, in both sheets 30.

An advantage of having the holes 190 preformed in the panel in some or all of the stiffening formations 40 is that it provides flexibility in the composite panel construction. In particular if the panels are cast on site, a construction worker can select the stiffening formations to receive a connector (based on design requirements) and merely bolt the connectors to those formations without the need to drill the holes on site.

The concrete (or other cementitious material) poured over the decking and the fixed connector (s) .

In this embodiment the coupling portion 184 is exposed along an edge surface of the decking such as upper side 16. This is advantageous for when lifting. This upper side 16 is conveniently raised by the crane, and then is properly placed to connect to the top plate 90. The passage 188 opens to the upper side 16 of the panel assembly 10.

Some variations on the specific embodiments include:

• the sheet elements may have any suitable form and may be profiled to include stiffening formations that are formed as open or closed ribs and/or angled side margins;

• the settable material may be a polymer;

• the connector may be arranged to engage a hook, carabineer or shackle instead of a screw thread;

• the connector may be disposed so as to allow face lifting of the panels; and • the attachment portion may be arranged so that the web is located within a recess or rebate of the attachment portion.

In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word "comprise" and variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the process and apparatus.

It will be appreciated that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.