Field of the Invention

[0001 ] This invention relates to a composite building panel, particularly to the type that includes a shell formed from a sheet material, and filled with an aerated concrete admixture.

Background of the Invention

[0002] Composite building panels, of the type having an outer shell made from a suitable sheet metal material, and a concrete material infill are known. Even composite building panels having an aerated concrete material infill are known. There are however a number of problems associated with this type of composite building panel.

[0003] Firstly, it is difficult when pouring the wet concrete material into the outer shell to keep the concrete infill dimensionally stable during the curing process. Also when standard Portland cement are used, the curation process generates a significant amount of heat, which may adversely affect the integrity of the outer shell material, or cause it to warp out of shape, or undesirably affect its surface appearance. Portland cement also produce a significant amount of greenhouse gases as it is produced. To compensate for these problems, geopolymer based cements are used. However, these are typically difficult to aerate. It is desirable to have a substantially even distribution of uniformly sized and shaped bubbles throughout the geopolymer. It is important that the aerated geopolymer maintain this distribution during the curation process. This is difficult to achieve.

[0004] Secondly, when the composite building panel is subjected to extreme loads, such as those encountered in a geological event like an earth tremor or earthquake, the forces encountered by the composite structural panel may cause either the concrete material infill or the outer shell, or both to fail. One mode of failure results when the infill separates from the inner wall of the shell, thereby allowing the shell to move laterally across the surface of the infill material. This may cause the shell to bulge, buckle or tear. Another mode of failure is due to the sudden failure of the concrete infill material to maintain its structural integrity. Depending upon the type of load it is exposed to, the concrete material may crack or crush, which may lead to catastrophic failure of the composite building panel, and subsequently the sudden collapse of the entire structure.

[0005] It is a goal of the present invention to create a composite building panel that ameliorates at least some of the aforementioned problems.

Disclosure of the Invention

[0006] In one form, the present invention is a composite bui lding panel of the type including an outer shell, wherein the inner walls of said shell define an interior space. The interior space is then substantially filled with a suitable wet aerated concrete material. The wet aerated concrete material maintains its volume and shape during the curation process. The concrete material remains aerated when the concrete material has cured.

[0007] Preferably, the bubbles incorporated into the aerated concrete material are evenly distributed throughout the wet concrete material, and remain evenly distributed throughout the outer shell after the concrete material has cured.

[0008] In one form, the aerated concrete includes a plurality of fine polymer filaments that are evenly distributed throughout the concrete material when it is wet, and remain evenly distributed within the outer shell when the concrete material has cured.

[0009] In another form, the aerated concrete includes a plurality of very fine carbon filaments that are evenly distributed throughout the concrete material when it is wet, and remain evenly distributed within the outer shell when the concrete material has cured.

[0010] Preferably, the aerated concrete includes a plurality of both fine polymer filaments and a plurality of very fine carbon filaments that are each evenly distributed throughout the concrete material when it is wet, and each remain evenly distributed when the concrete material has cured within the outer shell. [001 1 ] The inclusion of either the fine polymer filaments, or the very fine carbon filaments, or a combination of both, improve the concrete material infill 's tensile strength and flexure resistance, particularly in relation to severe vibratory events, such as earth tremors or earthquakes.

[0012] Preferably, the outer shell is fabricated out of a suitable sheet metal material.

[0013] Alternatively, the outer shell is molded from a suitable polymer material.

[0014] Alternatively, the outer shell is fabricated out of a fibre reinforced composite including either inorganic or organic polymer.

[0015] Preferably, the outer shell is extruded.

[0016] Preferably, both the inner and outer walls of the outer shell include an embossed pattern.

[0017] Preferably, the embossed pattern is a repeat pattern. [0018] Preferably, the repeat pattern is diamond shaped.

[0019] The repeating diamond shaped pattern on the inner walls of the shell improves the grip between the outer shell and the concrete material infill.

[0020] The use of the repeating diamond shaped embossed pattern allows the shell to be fabricated from thinner material, thereby reducing the weight for the composite building panel, and reducing material cost, and finally reducing the amount of energy required to conduct the embossing operation. The embossed pattern assists in enabling the shell to resist the stresses and strains imposed upon it when the panel is subjected to events resulting in severe vibratory loads without buckling, bulging, or tearing, or the like, or otherwise losing contact, at least in a region, with the concrete material infill. [0021 ] In another form, the present invention i s a composite building panel of the type including an outer shell, wherein the inner walls of said shell define an interior space, and wherein said interior space is then substantially completely filled with a suitable wet concrete material. The wet concrete material maintains its volume and shape during the curation process. The concrete material is aerated when wet, and remains aerated when cured. Either a plurality of fine polymer filaments, or a plurality of very fine carbon filaments, or a combination of both, are included in the wet concrete material, and are substantially evenly distributed throughout the wet concrete material, and remain substantially evenly distributed after curation of the concrete material has occurred, and the polymer and/or carbon filaments improve the concrete material's tensile strength and flex resistance. The outer shell includes a repeating embossed pattern either upon the inner walls, or the outer walls, or both, and when the embossed pattern is included on the inner walls, it improves the grip between the shell and the concrete material, and when it is included on the outer walls, it improves the shell's resistance to vibratory loads, allowing the shell to reduce the likelihood of the shell bulging, buckling or tearing, so that the composite building panel has significantly greater failure resistance to geological events, such as earth tremors or earthquakes.

[0022] In another form of the present invention, a first plurality of additional longitudinal ribs are included, and the addition of these ribs thereby reduces the amount of embossing required on the shell, so that the effects of the combination of the additional longitudinal ribs, and the areas of embossing, combine to increase the strength, flexure resistance, and failure resistance, of a composite building panel, particulai'ly when the composite building panel is subjected to severe vibratory loads, particularly from a geological event, such as an earthquake, or an aftershock.

[0023] Preferably, each longitudinal rib, within the first plurality of longitudinal ribs, is trapezium shaped.

[0024] In another form of the present invention, the outer shell includes a second plurality of longitudinal ribs that extend partially inwardly from each side of the outer shell. [0025] Preferably, each partially inwardly directed rib, within the second plurality of longitudinal ribs, is T shaped.

Brief Description of the Drawings

[0026] Figure 1 is an isometric view of an example composite building panel that is made in accordance with the present invention.

[0027] Figure 2 is an isometric view of another example composite building panel that is made in accordance with the present invention.

Detailed Description of the Preferred Embodiments

[0028] We are shown in Figure 1 an isometric view of a preferred embodiment of a composite building panel 1 that is in accordance with the present invention. The composite building panel 1 comprises an outer shell 3 which is completely filled with a suitable concrete infill concrete material 5. In this embodiment, the panel is rectangular shaped, and includes a tongue portion 7 on the top edge, and a corresponding groove portion 9 on the other. The composite building panel 1 shown in this illustration, includes a first plurality of longitudinal ribs 13.

[0029] The sides of the panel 1 between the tongue portion 7 and the groove portion 9 include an embossed repeating pattern 1 1. In this example, the repeating pattern is diamond shaped, however any suitable pattern could be used, and still fit within the scope of this invention.

[0030] As shown in Figure 1, the embossed repeating pattern 1 1 is included on the exterior surface of the outer shell 3, and on the interior surface of the outer shell 3.

[0031] The embossed repeating pattern 3 on the interior surface increases the grip between the concrete infill material 5 and the outer shell 3. This significantly reduces the likelihood of slippage between the outer shell 3 and the concrete infill material 5, when the composite building panel 1 is under severe vibratory load, like that experienced in an earth tremor or earthquake.

[0032] The repeating embossed pattern also enables the outer shell 3 to withstand the successive severe compressive and strain loads generated by earth tremors and earthquakes without buckling, bulging or tearing.

[0033] A sample of the core of the composite building panel is shown in Figure 2. We can see a cured aerated concrete admixture 15. The aerated concrete admixture 15 includes a geopolymer that incorporates a plurality of gas filled voids 17. The gas filled voids are substantially evenly distributed throughout the aerated concrete admixture 15. The aerated concrete admixture 15 also includes a plurality of fine filaments of polymer material 19. As shown, these are also substantially evenly distributed throughout the geopolymer sample. In addition to these, in a preferred embodiment of the invention, a plurality of very fine filaments of carbon 21 are also included. The filaments of polymer and carbon, 19 and 21 respectively, combine with the geopolymer 3 to form a micro concrete through the walls between the gas filled voids 17. This creates an advantage where the material maintains its aeration during the pouring, and curation process. Their presence also greatly enhances tensile strength and flex resistance of the aerated concrete admixture 1 once cured.

[0034] To further improve the properties of the aerated concrete admixture 15, the geopolymer 15 includes a significant amount of either class F or class C fly ash 23 that is also substantially evenly distributed throughout the geopolymer 15. In a preferred embodiment of the invention, the geopolymer 15 also includes a significant amount of very fine sand 25. The inclusion of these materials to the geopolymer greatly enhances the compressive load resistance of the cured aerated concrete admixture 15.

[0035] The present invention has greatly improved pull -strength of fixtures and fittings that incorporate the aerated concrete admixture 15, when compared to typical aerated concrete materials. Also, building panels that incorporate the aerated concrete admixture 15 have the advantage that the aerated concrete admixture 1 incorporated remains dimensionally stable during the curation process.

[0036] The composite building panel, after curation has completed, has significantly increased flexural load resistance, and can also withstand greater vibration loads from exposure to geological events, such as earthquakes and tremors due to the combination of the improved core and the improved shell.

[0037] Turning to Figure 2 we are shown a second preferred embodiment wherein a T shaped longitudinal rib 15 is included and extends partway from an internal side wal l of the outer shell 3. The combination of the T shaped rib 15 and the embossed repeating pattern 1 1 combine to improve the mechanical performance of the composite building panel, particularly during a seismic event. The T shaped rib may be included when the outer shell 3 is extruded.

[0038] While the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the essenti al features or the spirit or ambi t of the invention.

[0039] It will be also understood that where the word "comprise", and variations such as "comprises" and "comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

[0040] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge.