NL1043067B1 - Structural panel with steel core and layers and method for providing such a panel - Google Patents

Abstract

The present invention pertains to a structural panel comprising at least one twodimensional supporting layer of polystyrene and attached thereto a rigid structure that covers the supporting layer, which structure extends from one side of the supporting layer, wherein the rigid structure is a steel frame structure made of Light Gauge Steel (LGS). The invention also pertains to a method for producing such a panel.

Description

STRUCTURAL PANEL WITH STEEL CORE AND LAYER AND METHOD FOR PROVIDING SUCH A PANEL

FIELD OF THE INVENTION

The present invention pertains to a structural panel, i.e. a panel having sufficient rigidity 10 to be used as seif-supporting building element, for example as a wall, floor, roof of a housing, building, offices, boats etc., and having the capacity to act as an insulating barrier for heat and optionally sound.

BACKGROUND OF THE INVENTION

Structural panels are known since the 1930’s of last century and commercially since the 1970’s. A huge advantage of such panels is that they can be made remote from an actual building site (i.e. a site where the ultimate construction is assembled, which construction could for example be a building or a mobile unit such as a container, truck or boat) under controlled circumstances to allow good and consistent quality, where after they are used to build a construction at an actual building site under less favourable circumstances. Nowadays, structural panels are commonly used in the construction industry. In particular insulated panels, commonly in the form of a so-called sandwich panels, wherein a layer of an insulating material is sandwiched between two opposing two-dimensional supporting layers of a structural board material, are widely used in the construction industry for making buildings and other constructions. In such panels, also denoted as SIP-panels, the rigidity as well as the insulating properties comes about due to the central layer of a foamed material. Such panels in fact share the same structural properties as an I-beam or i-coiumn. The rigid insulation core of the structural panel acts as a web, while the outer board or boards fulfill the function of the flanges. The board typically consists of sheet metal, plywood, cement, magnesium oxide board (MgO) or oriented strand board (OSB) and the core either expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), polyisocyanurate foam, polyurethane foam or composite honeycomb (HSC). In the latter material innumerable thin aluminum or composite hexagonal columns are gathered in a honeycomb form and bonded in a sandwich manner to meta! or resin plates.

The central layer with rigidity of the structural panel according this invention is known as steel frame building. Steel frame building is not the same as more well-known stee!

frame construction. There are both types of similarity, a low own weight and a high construction speed, but constructively huge differences. Steel frame construction is a construction of relative heavy linear elements such as beams and columns of hot-rolled profiles. For the completion needs this skeleton to be filled in with wails, floors and roofs. Stee! frame building also named steel framing is done with complete panels for 10 walls, facades and roofs. At the basis of which stand frames of cold-formed mainly C and U-profiles, made of thin steel plate often named Cold Formed Steel (CFS) also known as Light Gauge Stee! (LGS). CFS frames and components are produced and fabricated from structural quality steel coils and are shaped at ambient temperatures by roll-forming machines. They can be produced in large quantities and at high speed with consistent quality and precision. The wide range of advanced tooling functions provided by systems allow high productivity and versatile output to produce roof trusses, wall frames, and floor joists, all to exact measurements, saving time and costly wastage in the construction stage. The CFS frames are mainly bolted, nailed or glued together but not by welding, because the steel is rather thin. For designers and builders are the constructive differences with steel frame construction of essential importance. Steel frame building is very much like metal stud. Again not in a constructive way: for metal stud, the steel profiles are about 0,6 mm thick and have no load-bearing function. A steel frame with profiles of 1 to 4 mm has that function well. In that respect, steel frame construction is just 'thick metal stud'. In addition, has steel frame building logically more 25 through the two- or three-dimensional constructions spatial and aesthetic possibilities.

Steel frame building is a contemporary variant of timber frame construction, better known as HSB, and prefab concrete. More and more steel frame construction is seen as a better alternative. It combines namely the advantages of HSB with the advantages of steel: lighter weight, more suitable thanks to shrink-free materials, less sensitive to

- 30 climatic influences one resistant to pests and fungi. There are also larger spans and knockouts feasible. An extra distinction with prefab concrete is the weight and the shorter delivery time, because steel framing does not work with molds. The additional benefit of this is a wider design freedom for small numbers at relatively low costs. Steel frame building goes well with other building systems. The combinations with steel frame 35 construction are now numerous; the reason is clear: large, column-free and flexibly layout able floor plans. For example the combination of steel frames and steel frame construction: with steel frame construction, buildings up to six layers can be used as a kind of seif-supporting bodywork, for higher buildings, a steel skeleton can serve as the main supporting structure, whereby the walls, floors and roofs of steel frame building elements are made. The combination of three building methods in one project is also possible: So are elements of steel frame construction, steel frame construction and timber frame construction. The prevent invention will be a combination of steel frame construction as rigid core in a structural panel.

OBJECT OF THE INVENTION

It is an object of the invention to provide an alternative structural panel. It is a further object of the invention to provide for a method to produce such a panel.

SUMMARY OF THE INVENTION

In order to meet the first object of the invention a structural panel has been devised comprising at least one two-dimensional supporting layer and attached thereto a rigid structure that covers the supporting layer (providing structural rigidity to the panel), walls of which structure extend from one side of the supporting layer (not excluding that a second rigid layer may extend from the other side of the layer), wherein the rigid structure is a steel frame structure.

In the present invention, the function of providing rigidity and insulation has been separated, contrary to the combined function a prior art foam material has in typical sandwich panels. This provides a higher degree of freedom to construct such panels. The steel frame structure provides for the rigidity of the structural panel, and the open space in the steel frame structure can be filed with an insulation material. This material may be as simple as gas (e.g. under vacuum), glass wool, stone wool, but can of course be any known or to be discovered insulation material. The steel frame structure provides the opportunity to obtain maximum rigidity white using a minimum of material, still leaving a large open space. Honeycomb panels are known as the best performance of effectively between rigidity, material use and open spaces but typically known with paper (cardboard), plastic (3D printed) or also metal (typically aluminium). Applicant is the first to recognise that a honeycomb structure can advantageously use for this purpose in combination with steel frames construction. The reason for this is clear: a honeycomb structure is a 3D structure of which the height is very large with respect to the thickness of the wail. The known honeycomb panels are used for producing articles that have completely contrary properties: typically such articles are relatively thin plate-like items such as pane! board to replace wood planks, doors or boards. There is an obvious reason for this: the height an article may have with a honeycomb core is at most a few centimeters. Therefore, honeycomb cores has been almost exclusively used for thin plate like articles such as structural panels with a thickness up to a couple of centimeters. It is noted that it is known to produce low end non plate like articles, such as car bumpers. Applicant found that by constructing a honeycomb panel by using a core of multiple one-dimensional sheet-in-parts of steel, which can be produced with steei frames technology without needing to compromise any of the current mechanica! demands have sufficient rigidity to act as self-supporting wails of a building, while at the same time being capable of providing adequate heat insulation, thus having a thickness of more than at least 10 centimeter till 25 centimeter (or more).

In order to meet the second object of the invention a method of producing a structural panel is devised, the method comprising producing a two-dimensiona! supporting layer, producing a supporting iayer of polystyrene, and attaching by glue or adhesive tot the 20 stee! frame structure to one side of the supporting iayer.

DEFINITIONS

A honeycomb structure is a structure consisting in essence (for more than 50%; in particular for more than 60, 70, 80, 90, 95 up to 100%) out of regular hexagons.

A polyfoam, is styrene (PS), is a material in essence (for more than 50%: in particular 30 for more than 60, 70, 80, 90, 95 up to 100%) such as PS, expanded polystyrene (EPS), extruded polystyrene (XPS) or other and new products based on polystyrene.

A two dimensional item means that the item extends in essence in 2 dimensions, i.e.

having a length and width far greater (more than 10 times, preferabiy more than 15, 20, 35 or even 25 times) than its thickness.

A. one dimensional item means that the item extends in essence in one dimension, i.e. having a length far greater (more than 10 times, preferably more than 15, 20, or even 25 times) than its height and width.

To extend in essence in a direction perpendicular, means to divert no more than 5’ from a perpendicular direction, in particular no more than 4°, 3°, 2^s, 1° or 0°.

A multiple one-dimensional sheet-in~parts item is a structure composed out of equal pieces of one dimensional.

To fill an open space with material is to put the material in the space such that at ieast 50% of the open space is taken by the materia!, preferably at least 60, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99 or up to 100% of the open space.

A Stee/ Frame Building or Steel Frame Structure, also named Cold Formed Steel (CFS) or Light Gauge Steel (LGS) are mainly C and U-profiles of thin plate steel which are cold-formed from coils.

A cement based product, is a product made partially with cement, but also e.g. sand, 20 water, such as concrete.

EMBODIMENTS OF THE INVENTION in the first embodiment of the present inventation a structurai panel is a steel frame structure made of Light Gauge Steel (LGS) and at least one of the supporting layers are made of polystyrene (PS), such as (expanded polystyrene) EPS or (extruded polystyrene) XPS.

In a second embodiment of the present inventation a structural panel is a steei frame structure made of Light Gauge Steei (LGS) and at ieast one of the supporting layers are made of polystyrene (PS), such as (expanded polystyrene) EPS or (extruded polystyrene) XPS and which is elaborated with a cement based product, such as 35 concrete, on the outside of the panel.

In a third embodiment of the present inventation a structural panel is a steel frame structure made of Light Gauge Steel (LGS) and supporting layers are made of polystyrene (PS), such as (expanded polystyrene) EPS or (extruded polystyrene) XPS which is formed on the outsides partially of an omega profiles, 5 sinusoidal profiles, trapezoidal profiles or pyramid profiles as foundation for the cement based finishing off product.

In another embodiment of the present inventation a structural panel is a steel frame structure made of Light Gauge Steel (LGS) and supporting layers are made of polystyrene (PS), such as (expanded polystyrene) EPS or (extruded polystyrene) XPS which formed on the outsides such a functional form as foundation that optimizes the strength of the cement based finishing off product.

In another embodiment of the present invention the steel rigid structure of the structural 15 panel is made in the shape of honeycomb or sinusoidal profiles, This because this form gives the optimal support to the supporting layers and is the most efficient possibility to adapt strength with less as possible material.

In another embodiment of the present invention the walls of the honeycomb structure 20 extend in essence in a direction perpendicular to the plane in which the supporting layer extends. Although such a constitution is known for honeycomb structures of other core materials such as paper, aluminium and plastic, it is not known for steel structures with a thickness of the honeycomb structure of at least 10 cm. This is because applicant found that it is possible by leaving the common production techniques of making the 25 honeycomb in one go, but assembling the honeycomb out of separately made smaller structures.

In an additional embodiment of the present invention the inventor recognized to assembling the honeycomb out of smaller separate steel structures or in other words 30 one dimensional sheet-in-part item with a sinusoidal or corrugated profiles form over the long side, so the profiles can be produced in a roll forming machine.

In an additional embodiment the thickness of the honeycomb structure is at least 10 cm, preferably at least 20 cm. This provides the option of having a greater volume available 35 for an insulating material and creating better rigidity. In the art, no 3D objects have been made of steel structures having a depth greater than a couple of centimetres. In the current invention, by using a honeycomb assembled out of separately made smaller structures, any height (depth) can be created for the honeycomb structure.

In another embodiment the panel comprises a second two-dimensional supporting layer that is attached to the polygon structure at a side of the panel opposite to the side of the first supporting layer. This way a sandwich panel can be formed.

In yet another embodiment of the structural pallet according to the invention, the open spaces in the steel frame structure are filled with insulating material. In a further embodiment wherein the insulating material can be injected to fill the open spaces in the steel frame structure. In a further embodiment wherein the insulating material is premanufactured as a self-supporting material (e,g. a polymer foam material), the premanufactured insulating material is cut (e.g. in situ) to dimensions corresponding to the polygon structure to fill the open spaces.

Inventor Is the first to recognize a structural panel can be composed with a rigid core of steel frame structure made of Light Gauge Steel (LGS) which will be glued with binder or adhesive to a supporting layer of polystyrene, which is directly the mould for the most outer layer of cement based finishing product.

In yet a further embodiment multiple separate one dimensional hexagon-in-part items are made, which are assembled in the panel to form the hexagon structure as rigid core of the structural panel. Thereafter, it is only a small step to assemble a structural board by gathering the polygon-in-part items on a supporting layer to form a honeycomb structure.

The invention will now be explained in more detail using the foilowing non-limiting exam pies.

EXAMPLES

Figure 1 schematically shows a structural panel according to the invention.

Figure 2 schematically shows multipie one dimensional sheet-in-part items, partly assembled into a honeycomb structure,

Figure 3 schematically shows a rigid core of a structural panel in form of sinusoidal or corrugated profiles according to the invention.

Figure 4 schematically shows a one dimensional sheet-in-part item bended till U~profile. Figure 5 schematically shows multiple one dimensional sheet-in-part items bended till

U-profile, partly assembled into a honeycomb structure with on both outsides a twodimensionai supporting layers made of polystyrene which are on the outside formed in trapezoidal profiles.

Figure 1

Figure 1 schematically shows a structural panel 1 according to the invention. This panel as depicted consist of a two-dimensional supporting layer 2 made of polystyrene (which in this case is assembled out of multiple plan-parallel sub layers) and a rigid honeycomb structure 3, which extends from one side of the supporting layer. This rigid steel structure is made from Light Gauge Steel (LGS) and has a height of 20 cm. Typically, although not shown, the hollow spaces in the rigid honeycomb structure are filled with an insulating material, where after a second two-dimensional supporting layer is put on top of the panel to seal the honeycomb structure with its insulation. After that, depending I.a. on the mechanical properties of the panel, on the outside in the direction simultaneously to the direction in which the supporting layer extends, of the polystyrene two-dimensional supporting layer 2 can be put a cement based finishing off product. The panel can be used as a part in the construction of a building, e.g. as a wall, roof part etc. as substitute for e.g. prefab concrete etc.

In the shown embodiment, the honeycomb structure is assembled out of multiple onedimensional honeycomb-in-part items (which becomes more dear when looking at figure 2) positioned on a separate two-dimensional supporting layer,

Figure 2

Figure 2 schematically shows multiple one dimensional honeycomb-in~part items 30, partly assembled into a honeycomb structure. Individual one dimensional honeycombin-part items 30 and 30’are shown in the lower right part of figure 2. These part in essence extend in only one dimension and can be produced in like a common Light Gauge Steel (LGS ) by using a press and/or roll forming machine that as is commonly known in the art. These parts, after having been made, can be assembled to form a honeycomb structure, such as the honeycomb structure as shown in figures 1 and 2, In figure 2, four separate one dimensional honeycomb-in-part items 30, 30’, 30” and 30”’ are shown to be assembled to form a honeycomb structure corresponding to the structure of figure 1.

As shown, in this embodiment each pair of abutting one dimensional honeycomb-in-part items has mutual mechanical elements 300 and 301 that mate to form a mechanical connection between the two items. Such elements can be as simple as mating ridges as shown in figure 2. Such mating elements have been to greatly increase the strength of the rigid honeycomb.

Figure 3

Figure 3 schematicaily also shows multipie one dimensional honeycomb-in-part items 30. corresponding to the structure of figure 1. The form of the multiple one dimensional honeycomb-in-part items 30 in figure 3 is now only more sinusoidal or corrugated.

Figure 4

Figure 4 schematically shows multiple a one separate one dimensional honeycomb-inpart bended till U-profile, which can to be assembled to form a honeycomb structure corresponding to the structure of figure 1.

Figure 5

Figure 5 schematically shows a structural panel 4 according to the invention. This panel as depicted consist of a two-dimensional supporting layer 5, in this figure on the outside formed as trapezoidai profile, made of and a rigid honeycomb structure 3, which extends from one side of the supporting layer. This rigid steel structure is made from Light Gauge Steel (LGS).Typically, although not shown, the hollow spaces in the rigid honeycomb structure are filled with an insulating material, where after a second twodimensional supporting layer 6 is put on top of the panel to seal the honeycomb structure with its insulation. After that, depending i.a. on the mechanical properties of the panel, on the outside in the direction simultaneously to the direction in which the supporting layer extends, of the polystyrene two-dimensional supporting layer 5 and 6 can be put a cement based finishing off product 7.

Not shown in this embodiment, the tongue and groove outskirts 8 .

Claims (15)

A construction panel comprising at least a two-dimensional support layer 5 made of polyfoam (such as PS, EPS, XPS, PIR, PUR), and attached to it on the inside a light steel frame structure covering the support layer, walls of which structure extend from one side of the support layer, characterized in that the support layer to the rigid steel structure are made as separate parts before assembling to form the panel. A building panel according to claim 1, wherein the building panel consists of at least a two-dimensional support layer made of polyfoam, which is partly formed on the outside in omega profiles, sinusoidal profiles, trapezoidal profiles or pyramid profiles. A building panel according to any one of the preceding claims, wherein on the outside of the support layer in the simultaneous direction in which the support layer extends, it is finished with a cement-based product, such as concrete. 20 A building panel according to any one of the preceding claims, comprises a second two-dimensional support layer attached to the rigid structure on one side of the panel opposite the side of the first support layer. A building panel according to any one of the preceding claims, characterized in that the open spaces in the metal structure are filled with insulating material. A construction panel according to any one of the preceding claims, wherein both sides have a two-dimensional support layer made of polyfoam and each outside of the support layers are covered with a cement-based material. A building panel according to any one of the preceding claims, wherein the rigid light steel frame construction is partly a honeycomb construction which is composed of several one-dimensional plate parts. A building panel according to claim 7, wherein the honeycomb structure is composed of several one-dimensional plate parts in the form of sinusoidal or corrugated profiles. A building panel according to any one of the preceding claims, wherein at least one of the two-dimensional supporting layers is made of a polyfoam in which 5 recesses are made on the inside in which the steel one-dimensional plate parts of the light steel frame construction fit exactly, both the recesses and the corresponding steel frame construction have the same widths therein. A building panel according to any one of the preceding claims, characterized in that At least one support layer is glued together with the steel one-dimensional plate parts of the light steel frame construction. 11. A building panel according to any one of the preceding claims, wherein at least one of the two-dimensional support layers is made of a polyfoam and has a tongue and groove on the four sides for an exact matching connection to another support layer or steel exterior with the same tongue and groove outside. 12. A building panel according to any one of the preceding claims, wherein the light steel frame construction on the outside of the building panel has a steel profile which is higher than the two-dimensional supporting layers and which is at least at the same height as the cement-based material, in order to form a mold act when the cement-based material is applied. 25 A building panel according to claim 12, wherein the steel exterior profile is provided on the inside with tongue and grooves communicating with the tongue and groove of the polyfoam support layers. A building panel according to any one of the preceding claims, wherein the 30 honeycomb construction, including in the form of sinusoidal or corrugated profiles, are composed of several one-dimensional plate parts that are at least partly bent into U-profile, C-profile, Z-profile, or Omega-profile beams. A building panel according to any one of the preceding claims, characterized in that The thickness of the one-dimensional metal sheet parts and the rigid structure are at least 0.5 mm and at most 3 mm.