COMPOSITE STRUCTURAL MEMBER WITH THERMAL AND/OR SOUND INSULATION CHARACTERISTICS FOR BUILDING CONSTRUCTION
The invention relates to a composite structural member with thermal and/or sound insulation characteristics for a building, comprising an insulating board shaped as web part and at least one protective element whereby the web part has two opposing abutting faces and two main surfaces being arranged rectangular to the abutting faces, whereby the board is made of mineral fibres and a binder and whereby the at least one protective element is substantially U-shaped in cross section, having two legs erecting parallel to each other and being connected to the web part, whereby abutting faces of at least one web parts are covered by protective elements, which in combination with said web part take up loads parallel and/or rectangular to the main surfaces of the web part and which are not in direct contact to each other.
The invention relates to a composite structural member with thermal and/or sound insulation characteristics for building construction comprising an insulating board shaped web part and at least one protective element, whereby the web part has two opposing abutting faces and two main surfaces being arranged rectangular to the abutting faces.
The present invention sets out to provide composite structural members such as columns, studs, beams, bracings, joists, rafters, purlins, trusses, mounts, and supports, as used in frames, walls, roofs, floors, doors, windows, and other building structures and substructures. They may be designed or utilized for load-bearing and load distribution or stabilizing functions as well as for secondary members or even simple, non-load-bearing substructures.
Generally structural members as well as composite structural members are well known.
Typical structural members within building construction are e.g. steel products in the form of hot rolled long products (often referred to as “sections” or “profiles”). They are often used for the main frame members (columns, beams, bracings). Said hot rolled products mainly appear as e.g. I, H and channel sections, Angles or hollow sections. Nowadays these sections often undergo various transformations through cutting, welding, bending etc., in order to obtain very different shapes and improved performance. In this way, e.g. cellular beams can be fabricated from I or H sections by cutting and welding.
Besides those hot rolled long products, cold formed long products formed from thin sheet steel are widely used as secondary members, e.g. for cladding (rails) and roofs (purlins). Typical shapes are C, U or Z sections.
Steel offers exceptional qualities in terms of mechanical resistance but typically provides undesirable thermal characteristics.
Traditionally wood has been used to a large extent in some variations and in various types of different structures. However, wood has increased in price and quality structural lumber has decreased in availability. Moreover, strength and safety requirements within the building regulations have increased during the years and therefore the use of wood is somewhat limited, in particular in respect to e.g. multi-storey structures.
Furthermore, during the past decade composite structural members have been developed in order to overcome some of the before mentioned drawbacks. Those members often employ a wooden web with wooden flanges on both edges of the web, or combinations of web parts from laminated wood/plywood or wood-based products, like e.g. OSB boards with wooden or wood based flanges. Such kind of wooden composite structural members which may often have the form of an I-beam are e.g. known as TJI-beam, commercially available from US based company TrusJoist. In order to increase the strength of those wooden composite members attempts have been made to include reinforcements. By way of example reference is made to U.S. Pat. No. 5,974,760A and U.S. Pat. No. 6,173,550B1.
Besides that, also composite structural members comprising various wooden or alternative materials for the web parts combined with metal flanges are known in the art. E.g. U.S. Pat. No. 6,301,857 B1 describes a rigid element as composite structural member comprising an elongated metal flange having a pair of parallel side walls joined at one end by a transverses base wall to form a web receiving pocket. The web is made from wood such as plywood and is elongate and has parallel wide sides and parallel narrow edges. Metal flanges are fixed to both opposite edges, whereby raised teeth of the metal flanges are penetrating into the web. This well known rigid element may have a high load bearing potential but is not easy to produce and does not have good insulation properties as the teeth penetrated into the web and may get into contact to each building up thermal bridges.
U.S. Pat. No. 6,161,361 describes a composite structural member having a pair of spaced apart longitudinally extending flanges and a plurality of thermally insulative conductive web connectors intermittently disposed between the flanges, the web connectors having a pair of opposing ends, each end being attached to a respective flange, wherein at least two of the web connectors are longitudinally spaced apart from each other, thereby forming at least one open cavity defined by at least some portion of the flanges and the at least two web connectors, whereby the web connectors and the open cavity minimize thermal conductance between the flanges. Therefore this prior art improves the insulation properties by reducing the material of the web and building up the cavity. Reducing the material of the web means to reduce the stability, especially the load bearing properties of the composite structural member. To receive a sufficient stability needs the use of very stiff materials which may according to the description be of the prior art plastic, especially recycled plastic.
A common drawback of all the above mentioned prior art structural members is their limited respectively undesirable thermal characteristics and their poor behavior in the event of a fire.
It is therefore an object of the present invention to provide a composite structural member, in the following also referred to as rigid element, which is easy to handle, easy to produce, which has excellent insulation and stability properties and which significantly improves the resistance to fire compared to prior art structural members.
According to the invention this object is achieved with a composite structural member having a board shaped web part, in the following also referred to as the board, made of mineral fibres, a binder and optional an additive, e.g. aerogel, and at least one elongate flange or protective element, whereby the at least one protective element is substantially U-shaped in cross section. The at least one protective element having two legs erecting parallel to each other and being connected to the board and whereby both abutting faces of the board are covered by protective elements, which in combination with the board take up loads parallel and/or rectangular to the main surfaces of the board and which are not in direct contact to each other.
Such a composite structural member can be used for thermal and/or sound insulation of a building façade and has increased thermal and/or sound insulation properties and is increased with respect to its stability properties due to the combination of an insulating material with at least one protective element, thereby completely avoiding thermal bridges. The protective elements protect the board against high loads, and with respect to the design of the protective elements a lot of loads, such as compression force and bending forces are transmitted by the protective elements in connection with the board.
Because of the combination of all features of the composite structural member according to the invention such composite structural member can for example be used with building elements of big lengths up to more than 12 meters. Such composite structural member can be handled easily because of the relatively low weight of the rigid element mainly made of mineral fibres.
Building elements according to the prior art always need profiled steel supports between the building beams which have a distance of about 3 to 6 meters. These steel supports have the function to take up loads from the building elements and transfer them into the building construction. A composite structural member according to the invention has the advantage that it can take up all loads directly and transfer the loads for example to building beams.
According to a further feature of the invention the composite structural member preferably can be fixed in a clamp fit way between legs of an integrated joint element. Preferably the composite structural member can be fixed to the insulating element and/or the integrated joint elements at least by gluing. Gluing the composite structural member to the insulating element and/or the integrated joint elements avoids fastening elements like screws, rivets or the like. Therefore, thermal bridges can be avoided easily.
According to a further feature of the invention a tensile element stiffens the composite structural member in a contact zone to the insulating element. Preferably the composite structural member has a fibre orientation directed between the protective elements. The fibre orientation has on the one hand an effect on the stiffness of the composite structural member and on the other hand an effect on the insulation properties of the composite structural member. The fibre orientation as described before increases the insulation properties of the composite structural member.
According to a further embodiment of the invention the composite structural member has two main surfaces of which one main surface is directed to the lateral surface of the insulating element, whereby the two main surfaces of the composite structural member are diverging to each other. This embodiment has the advantage to build up increased water tightness. Preferably the composite structural member has a main surface being capable to be connected with an adhesive.
To reach a higher stiffness of the composite structural member the composite structural member according to the invention comprises at least one board of mineral fibres and two protective elements, each being fixed to and covering at least partly one main surface and one lateral surface of the board whereby the protective elements are not in direct contact to each other. The composite structural member has an increased stiffness and does not build up a thermal bridge between the outer surfaces of the building element because of the missing contact between the two protective elements which may be made from metal.
Preferably the two protective elements are overlapping each other on opposed main surfaces of the board. According to a further feature of the invention the protective elements are L-, U- or T-shaped in cross section and made of sheet metal, e.g. steel or aluminium with a thickness of 0.5 to 3.0 mm. Thereby an effective section modulus can be achieved. Alternatively such elements might nowadays also be made of fibre reinforced resin providing comparable strength properties.
According to a further feature of this embodiment two protective elements are connected to each other by connecting means like rivets, screws or the like which run perpendicular to the main surfaces of the boards. Finally, two boards are connected by at least one clamp like protective element which fixes the two boards to each other.
Preferably the board is build up by at least two layers which are connected by at least one clamp like protective element. The layers can be glued together.
A composite structural member according to the invention has preferably protective elements being made from sheet metal. According to a further feature of the invention at least one leg of the protective element is inserted into one slit of the board, being arranged in one abutting face of the board.
Finally the composite structural member according to the invention has at least one protective element having a width being larger than the width of the abutting face of the board.
Furthermore the invention relates to a building having at least two building elements with a composite structural member as said before and being arranged between the building elements, each building element comprising an insulating element made of mineral fibres, comprising two large surfaces extending substantially parallel and with a distance to each other and four lateral surfaces extending substantially at right angles to the large surfaces, and a frame made of sheet metal and being arranged at least at two lateral surfaces being arranged at opposite sides of the insulating element. According to the invention the frame has integrated joint elements being formed correspondingly to each other and load bearing and wherein at least one integrated joint element comprises the rigid element having thermal and/or sound insulation characteristics and being made of mineral fibres and a binder whereby the corresponding integrated joint elements of the building elements are connected to each other in a form fitted way and by an adhesive being provided between the rigid element and the building elements facing to each other.
According to a further feature of the invention the adhesive between the composite structural member and the building elements is non-combustible.
Furthermore, the composite structural members are preferably connected to the insulating element and/or the integrated joint elements by an adhesive, preferably with an incorporated vapor barrier and/or a tensile element, for example a fibrous web.
Finally, each integrated joint element has at least two legs extending parallel to each other and being made from the sheet metal of the frame, which is connected to the insulating element, especially to the main surfaces of the insulating element and in that each leg is formed by bending a free end of the sheet metal.
The building element can be developed in the inventive way by incorporating one or all features which are already described above with reference to the composite structural member.
The invention will be described in the following by way of example and with reference to the drawing in which
An embodiment of the invention is shown in
The protective element 27 is made of sheet metal and U-shaped in cross section. Therefore, the protective element 27 has two legs erecting parallel to each other and connected to each other by a web being oriented rectangular to the legs. The distance between the two legs of the protective element 27 is equal to the thickness of the two boards 26 which are glued together by an adhesive 29. Furthermore, the adhesive 29 is provided between the main surfaces and the legs of the protective element 27 as well as between the lateral surfaces of the boards 26 and the web 30 of the protective element 27.
The second protective element 28 is made of sheet metal and is T-shaped in cross section. The second protective element 28 is arranged at the boards 26 opposite to the protective element 27 whereby the two lateral surfaces of the boards 26 are totally covered by a first leg of the protective element 28 and whereas the second leg of the protective element 28 spans between the two boards 26.
The two protective elements 27, 28 are not in contact with each other so that the composite structural member 13 according to
According to
The invention is not limited with respect to the embodiment according to
For example
The composite structural member 13 according to
A further embodiment of the rigid element 13 is shown in
The longer legs 36 of the protective elements 35 cover the main surfaces of the composite structural member 13. The length of the longer legs is shorter than the width of the board 26 but longer than half of the width of the board 26 so that both legs 36 of the two protective elements 35 can be easily connected by screws 38 made of synthetic material. Instead of screws 38 rivets can be used.
Yet another embodiment of the composite structural member 13 is shown in
The legs 32, 33 of the protective elements can have equal lengths. With respect to the length of the board 26 the length of the legs 32, 33 can vary in a range so that the legs 32, 33 of both protection elements 31 being arranged on one large surface of the board 26 cover nearly the whole large surface of the board 26 without getting into contact to each other. The length of the legs 32, 33 of one protection element 31 can be equal or different to each other.
Furthermore the board 26 can have two layers which two layers of the board 26 are connected by at least one clamp like protective element 31. Nevertheless the layers of the board 26 can be glued together by a non combustible adhesive.
The board 26 according to
Tests have proven that such boards 26 according to
The features described with respect to the composite structural member 13 according to
The load-bearing composite structural member 13 shown in
This load-bearing composite structural member 13 having a shape like an I-profile can be used as a column and/or a beam. When tested as a column this load-bearing composite structural member 13 having e.g. a length of approx. 2700 mm provided a bearing capacity of respectively 76 kN and 81 kN.
Moreover, the load-bearing composite structural member 13 according to
Such characteristics can be achieved by using a board shaped web part 26 having a density of about 400 up to 600 kg/m3, especially 500 kg/m3.
The before described webs can be made of mineral fibres in an amount of 90 to 99 wt-% of the total weight of starting materials in the form of a collected web and a binding agent in an amount of 1 to 10 wt-% of the total weight of starting materials, whereby the collected web of mineral fibres is subjected to a disentanglement process, whereby the mineral fibres are suspended in a primary airflow, whereby the mineral fibres are mixed with the binding agent before, during or after the disentanglement process to form a mixture of mineral fibres and binding agent and whereby the mixture of mineral fibres and binding agent is pressed and cured to provide a consolidated composite with a bulk density of 400 kg/m3 to 600 kg/m3, especially of 500 kg/m3. The percentages mentioned are based on dry weight of starting materials. A suitable method is e.g. disclosed and described in more detail in WO2011/012712 by the applicant.
Such webs can be produced in a versatile and cost-efficient method. By adjusting the density to which the web is pressed, a variety of different webs can be made tailor-made for specific purposes. Therefore, these webs have a variety of uses, predominantly as building elements. In particular the webs can be in the form of panels. In general, the webs are used in applications where mechanical stability and insulating properties are important. Preferably, the thickness of the web is from 4 to 25 mm depending on the intended use. The precise quantity of mineral fibres is chosen so as to maintain appropriate fire resistance properties and appropriate thermal and/or acoustic insulation value and limiting cost, whilst maintaining an appropriate level of cohesion, depending on the appropriate application. A high quantity of fibres increases the fire resistance of the element, increases its acoustic and thermal insulation properties and limits cost, but decreases the cohesion in the element. This means that the lower limit of 90 wt-% results in an element having good cohesion and strength, and only adequate insulation properties and fire resistance, which may be advantages for some composites, where insulation properties and fire resistance are less important. If insulation properties and fire resistance are particularly important the amount of fibres can be increased to the upper limit of 99 wt-%, but this will result in only adequate cohesion properties. For a majority of applications a suitable composition will include a fibre amount of from 90 to 97 wt-% or from 91 to 95 wt-%. Most usually, a suitable quantity of fibres will be from 92 to 94 wt-%.
The amount of binder is also chosen on the basis of desired cohesion, strength and cost plus properties such as reaction to fire and thermal insulation value. The low limit of 1 wt-% results in a web with a lower strength and cohesion, which is however adequate for some applications and has the benefit of relatively low cost and potential for good thermal and acoustic insulation properties. In applications where a high mechanical strength is needed, a high amount of binder should be used, such as up to the upper limit of 10 wt-%, but this will increase the cost for the resulting product and further the reaction to fire will often be less favorable, depending on the choice of binder. For a majority of applications, a suitable web will include a binder amount from 3 to 10 wt-% or from 5 to 9 wt-%, most usually as suitable quantity of binder will be from 6 to 8 wt-%.
The mineral fibre used for such a web could be any mineral fibres, including glass fibres, ceramic fibres or stone fibres but preferably stone fibres are used. Stone wool fibres generally have a content of iron oxide of at least 3% and alkaline earth metals (calcium oxide and magnesium oxide) from 10 to 40%, along with the other usual oxide constituency of mineral wool. These are silica; alumina; alkali-metals (sodium oxide and potassium oxide) which are usually present in low amounts; and can also include titania and other minor oxides. A fibre diameter is often in the range of 3 to 20 microns, in particular 5 to 10 microns, as conventional. The before described composite structural member 13 according to
Finally
The before described building element 1 has the big advantage that loads can be distributed directly to building beams because the building element itself secures the safe load bearing effect through the load bearing joint elements 6 in combination with the composite structural member 13. Therefore, the sandwich effect works crosswise to the length of the building elements 1 with a short span of 2 meters up to 2.5 meters which is a usual width of a production line for the production of insulating elements 2. The integrated load bearing joint elements 6 are substituting the normally necessary steel supports behind the building elements 1. The elements 1 therefore allow thermal bridge free systems.
Further advantages of the building elements 1 and buildings being built up with these building elements 1 and composite structural member 13 are achieved by using adhesives 16, 29 in various areas of the building elements 1. The use of adhesives 16, 29 makes it possible to reduce or to avoid screwing and dynamic loads are covered in a much better way along the whole building elements 1 and not only punctual. Therefore, the invention provides a building element 1 for example for all non residential buildings with new possible designs. The building elements 1 can at least be produced easily and have of course a better fire resistance compared to building elements 1 having a filling of e.g. plastic foams. Because of the reduced density of the insulating element 2 being inserted into the building element 1 low thermal conductivity of λ<35 mW/(mK) can be achieved. The building elements 1 can be produced in bigger units because the reduction of the bulk density of the insulating element 2 made of mineral fibres has the advantage of less weight. Bigger units have the advantage of a faster installation. Therefore, the invention has the advantages of fire safety, better acoustical performance, better energy efficiency and real sustainability. The building element 1 can have layers made of sheet metal with a profiling erecting parallel to the width of the building element 1. Building elements 1 with lengths up to 12 m and widths up to 2.5 m are possible.
Fixed to the longer lateral surfaces 4 are layers 5 made of sheet metal and building up a frame being arranged at two lateral surfaces 4 at opposite sides of the insulating element 2. Of course such layers 5 can also be provided at the shorter lateral surfaces 4. The layers 5 forming load bearing joint elements 6 which can be seen more precisely in
The layers 5 at the opposite lateral surfaces 4 have different shapes as can be seen from
As can be seen for example from
The layer 7 has a bigger length than the length of the insulating element 2. Therefore, the layer 7 extends over the large surface 3 of the insulation element 2. The part of the layer 7 extending over the insulating element 2 is bent twice so that a free leg 8 of the layer 7 erects parallel to the layer 7 whereby between the free leg 8 and the layer 7 an open cavity is formed.
In the area of the second large surface 3 of the building element 1 the layer is formed in a S-shape so that additional in this area the layer 7 forms together with a leg 9 an open cavity. The leg 9 is bent twice in perpendicular directions. A cavity 11 is formed between the leg 9 and a free leg 10 of the layer 7.
A reinforcing element 12 which is a more or less vapor-proof barrier and for example made of a glass fibre fabric or a foil is arranged in the cavities between the free leg 8 and the layer 7 on the first large surface 3 and between the leg 9 and the layer 7 on the second large surface 3. The reinforcing element 12 erects starting from the two cavities as described before parallel to a lateral surface 4 of the insulation element 2. Furthermore, the reinforcing element 12 is fixed with an adhesive inside the cavities as well as to the lateral surface 4.
A composite structural member 13 according to the invention is arranged between the two legs 8 and 10. This composite structural member 13 is fixed to the legs 8, 10 with an adhesive as well as with the reinforcing element 12.
The composite structural member 13 is fixed in a clamp fit way between the legs of the integrated joint element 6 being formed by at least the legs 8 and 10. The composite structural member 13 consists of fibres, aerogel particles and at least one binder, whereby 30 wt % mineral wool fibres, 60 wt % aerogel particles and 10 wt % binder are pressed and cured to a board having a density of 190 kg/m3. This composite structural member 13 has a thermal conductivity λ of 0.02 W/(mK).
As can be seen from
It is clear from the above description that the building element 1 as been shown in
In accordance with the before mentioned description it can be seen that two building elements 1 according to
As can be seen from
Furthermore, the beam 18 can be used to carry conduits 21 for water, gas or electric energy as it is shown in
A further stabilizing element is shown in
- 1 building element
- 2 insulating element
- 3 large surface
- 4 lateral surface
- 5 layer
- 6 load bearing joint element
- 7 layer
- 8 leg
- 9 leg
- 10 leg
- 11 cavity
- 12 reinforcing element
- 13 composite structural member
- 14 recess
- 15 planar surface
- 16 adhesive
- 17 hollow space
- 18 beam
- 19 side legs
- 20 bar
- 21 conduits
- 22 cover
- 23 profile element
- 24 screw
- 25 cavity
- 26 board/web part
- 27 protective element
- 28 protective element
- 29 adhesive
- 30 web
- 31 protective element
- 32 legs
- 33 legs
- 34 web
- 35 protective element
- 36 longer leg
- 37 shorter leg
- 38 screws
- 39 slit
Claims
1. Composite structural member with thermal and/or sound insulation characteristics for a building, comprising an insulating board (26) shaped as web part and at least one protective element (27, 28; 31; 35), whereby the web part has two opposing abutting faces and two main surfaces being arranged rectangular to the abutting faces, whereby the board (26) is made of mineral fibres and a binder and whereby the at least one protective element (27, 28; 31; 35) is substantially U-shaped in cross section, having two legs erecting parallel to each other and being connected to the web part, whereby abutting faces of at least one web parts are covered by protective elements (27, 28; 31; 35), which in combination with said web part take up loads parallel and/or rectangular to the main surfaces of the web part and which are not in direct contact to each other.
2. Composite structural member according to claim 1, characterized in that the web part has a bulk density of 150 kg/m3 to 600 kg/m3, preferably 150 kg/m3 to 400 kg/m3 and more preferably of at least 180 kg/m3.
3. Composite structural member according to claim 1 or 2, characterized in that the web part (26) is made of at least two layers being arranged sandwich like and connected to each other.
4. Composite structural member according to claim 3, characterized in that the layers of the web part have at least one main surface being capable to be connected with an adhesive.
5. Composite structural member according to one of the claims 1 to 4, characterized in that the two protective elements (27, 28; 31; 35) are overlapping each other on opposed main surfaces of the web part.
6. Composite structural member according to one of the claims 1 to 5 characterized in that the second protective element (27, 28; 31; 35) is L-, U- or T-shaped in cross section.
7. Composite structural member according to one of the claims 1 to 6, characterized in that the two protective elements (27, 28; 31; 35) are connected to each other by connecting means like rivets, screws or the like which run perpendicular to the main surfaces of the web part.
8. Composite structural member according to one of the claims 1 to 7, characterized in that two layers of the web part are connected by at least one clamp like protective elements (27, 28; 31; 35).
9. Composite structural member according to one of the claims 1 to 8, characterized in that the protective elements (27, 28; 31; 35) are made from sheet metal, especially steel and/or aluminium with a thickness of 0.5 mm to 3.0 mm.
10. Composite structural member according to one of the claims 1 to 9, characterized in that at least one leg of the protective element (27, 28; 31; 35) is inserted into one slit of the web part, being arranged in one abutting face of the web part.
11. Composite structural member according to one of the claims 1 to 10, characterized in that at least one protective element (27, 28; 31; 35) has a width being larger than the width of the abutting face of the web part.
12. Building having at least two building elements (1) with a composite structural member (13) according to one of the claims 1 to 11 being arranged between the building elements (1), each building element (1) comprising wherein the frame has integrated joint elements being formed correspondingly to each other and load bearing and wherein at least one integrated joint element comprises the composite structural member (13) having thermal and/or sound insulation characteristics and being made of mineral fibres and a binder whereby the corresponding integrated joint elements of the building elements (1) are connected to each other in a form fitted way and by an adhesive being provided between the composite structural member (13) and the building elements (1) facing to each other.
- an insulating element (2) made of mineral fibres, comprising two large surfaces extending substantially parallel and with a distance to each other and four lateral surfaces extending substantially at right angles to the large surfaces, and
- a frame made of sheet metal and being arranged at least at two lateral surfaces being arranged at opposite sides of the insulating element (2),
13. Building according to claim 12, characterized in that the adhesive between the composite structural member (13) and the building elements is non combustible.
14. Building according to claim 12 or 13, characterized in that the composite structural member (13) is connected to the insulating element (2) and/or the integrated joint elements by an adhesive, preferably with an incorporated reinforcing element, for example a fibrous web.
15. Building according to one of the claims 12 to 14, characterized in that each integrated joint element has at least two legs extending parallel to each other and being made from the sheet metal of the frame, which is connected to the insulating element (2), especially to the main surfaces of the insulating element (2) and in that each leg is formed by bending a free end of the sheet metal.
16. Composite structural member with thermal and/or sound insulation characteristics for a building, consisting of an insulating board (26) made of mineral fibres and a binding agent and shaped as web part and two protective elements (31) being arranged at opposing ends of the board (26), each covering an abutting surface of the board (26) and each having two legs (32, 33) being in contact with one of the large surfaces of the board, characterized in that the board (26) has a bulk density of 150 kg/m3 to 600 kg/m3 preferably 150 kg/m3 to 400 kg/m3 and more preferably of 180 kg/m3 to 400 kg/m3.
17. Composite structural member according to claim 16, characterized in that the board (26) is made of two layers.
18. Composite structural member according to claim 16 or 17 characterized by a bearing capacity of >60 kN when utilized as a column and/or >15 kN when utilized as a beam.
19. Composite structural member according to one of the claims 16 to 18, characterized in that the two legs (32, 33) of each protective element (31) are connected by at least one rivet or screw penetrating the board (26).
20. Composite structural member according to one of the claims 16 to 19, characterized in that the protective element (31) is made of sheet metal, e.g. of steel or aluminium or of fibre reinforced resin, especially resin reinforced by carbon fibres or fiberglass.
21. Composite structural member according to one of the claims 16 to 20, characterized in that the board (26) is made of mineral fibres in an amount of 90 to 99 wt-% of the total weight of starting materials in the form of a collected web and a binding agent in an amount of 1 to 10 wt-% of the total weight of starting materials, whereby the collected webs of mineral fibres is subjected to a disentanglement process, whereby the mineral fibres are suspended in a primary air flow, whereby the mineral fibres are mixed with the binding agent before, during or after the disentanglement process to form a mixture of mineral fibres and binding agent and whereby the mixture of mineral fibres and binding agent is pressed and cured to provide a consolidated composite with a bulk density of 400 kg/m3 to 600 kg/m3, especially 500 kg/m3.
Type: Application
Filed: Dec 18, 2013
Publication Date: Jul 7, 2016
Inventors: Peter Nowak (Gladbeck), Preben Riis (Roskilde), Jens Eg Rahbek (Frederiksberg), Klavs Koefoed Jakobsen (Roskilde)
Application Number: 14/739,782