This application is a §371 National Stage Application of PCT/AU2009/000448 filed Apr. 9, 2009, which claims priority to Australian Application No. 2008901785 filed Apr. 11, 2008.
The present invention relates generally to building components used in the building industry; in particular, although not exclusively, the invention relates to beams and building elements for the construction of buildings with roofs spanning large distances.
There are many instances in building construction requiring roofs covering large areas that are not obstructed with intermediate vertical supporting members such as columns. An example is a sporting or events stadium, where unobstructed views can be sold for premium prices. Seats in stadia with obstructed views are sold much more cheaply than those with a clear view. Another example of such a building is an aircraft hangar that must be wide enough and high enough to accommodate an aircraft having a large wing span and a high tail structure. This is especially true with the advent of so called “super-jumbos” such as the Airbus A380.
Various geometric shapes have been proposed in the prior art for roof structures that effectively cover a large area at a relatively low cost and without the use of intermediate supports. For example, it has been proposed that a roof have the shape of a hyperbolic paraboloid. However, such a roof structure may not be suitable as an aircraft hangar as its shape is predominantly ovular and may not be able to cover large aircraft.
Also, various materials are used in the building industry to form roof trusses. For example wood has been used for centuries to form roof trusses, while large modern buildings often employ steel roof trusses to span the width of a building. The I-beam (so called because of the shape of its cross section) also has been used to increase the strength and rigidity of roofs and reduce the weight of a roof structure. To create an I-beam steel webbing can be inserted between two parallel sections of steel. The design increases the torsional strength and moment of inertia of a beam while reducing the weight compared to a solid rectangular beam. Other materials used for beams include composites, alloys and plastics to prevent corrosion caused by chemicals and/or chemical reactions in environments such as phosphate storage facilities and acid storage facilities (e.g., galvanizing plants).
I-beams engineered from wood with fibreboard and a laminated veneer are also becoming increasingly popular in construction, especially residential construction, as such beams are both lighter and less prone to warping than solid wooden beams. However wooden I-beams can suffer a rapid loss of strength in a fire if left unprotected.
Similar to an I-beam, Australian Patent No. 716272 to Berryman discloses roofing beams made of sections that are then bolted or welded together. Each section consists of two parallel rectangular hollow tubes to reduce weight. A metal webbing is welded to the two parallel rectangular hollow tubes in a zig-zag pattern. The result is a lighter, more rigid structure.
However, disadvantages of the Berryman invention include accelerated corrosion rates due to pooling of water on the beam during storage and transportation. Such beams, even when painted or galvanized, once exposed to water when lying flat in a storage position may begin to rust or exfoliate.
The Berryman invention requires a coil of steel to be cut or slit to different widths to accommodate a range of beam sizes, then pressed to form its final shape. This process requires additional specialist equipment to cut the coil. This manufacturing process also requires carrying large stock levels of numerous different beam sizes. Also, due to long beam lengths specialist transportation companies may need to be enlisted to transport the beams.
There is therefore a need for improved beams that increase spanning capability, reduce corrosion, and are relatively easily manufactured and transported.
It is an object of the present invention to overcome and/or alleviate one or more of the above disadvantages or provide the consumer with a useful or commercial alternative.
It is a further object of some embodiments of the present invention to provide a beam having high torsional strength.
It is a further object of some embodiments of the present invention to provide a beam that is relatively easily manufactured and comprising components that are easily transportable to be assembled on-site.
It is a further object of some embodiments of the present invention to enable use of a single steel coil width for a variety of beam sizes.
It is a further object of some embodiments of the present invention to provide a beam that has reduced risk of corrosion, from water pooling, when in storage or when placed in a position open to the elements.
It is a further object of some embodiments of the present invention to provide corrosion-resistant beams for use in highly corrosive environments.
It is a further object of some embodiments of the present invention to provide a connection system for a beam structure to improve transportation, fabrication and construction of the structure.
According to one aspect, the present invention is a method of constructing a beam, the method comprising:
providing a first flange and a second flange defining a central beam axis;
providing a number of separately formed web sections each having two convergent side walls and a central wall extending between converging ends of the side walls,
arranging the web sections side by side in an alternating arrangement wherein the central walls of adjacent web sections are spaced substantially parallel to each other and are transversely staggered relative to the central beam axis;
connecting the side walls of adjacent web sections to one another; and
connecting the web sections to both the first flange and second flange.
Preferably, the web sections are arranged so that edge regions of adjacent side walls overlap.
Optionally, the method includes connecting the side walls of adjacent web sections to each other by passing fasteners through the region of overlap between adjacent side walls. Alternatively, the side walls of adjacent web sections are welded to one another.
In one embodiment of the invention, the central walls include gusset sections which extend past the upper or lower edges of the side walls and the method of constructing the beam includes positioning the flanges between the gusset sections.
Preferably, the gusset sections are flush with central walls of the web sections.
According to another aspect of the invention, the present invention is a method of constructing a building element which includes constructing at least two beams as claimed in any one of the preceding claims, and rigidly connecting the beams at an angle relative to each other by inserting parts of the flanges of each of the beams into holding channels of a connector and fixing the beams to the connector.
Preferably, the method includes inserting parts of the flanges into holding channels of a bracket, and fixing the beams to the bracket.
According to yet another aspect of the invention, the present invention is a beam comprising:
a first flange defining a central beam axis;
a second flange spaced parallel to the first flange; and
a number of separately formed web sections fixed between the first flange and the second flange, each of the web sections having two convergent side walls and a central wall extending between converging ends of the side walls;
the web sections being arranged side by side in an alternating arrangement wherein the central walls of adjacent web sections are spaced substantially parallel to each other and are transversely staggered relative to the central beam axis, and the convergent side walls of adjacent web sections overlap.
The beam may include fasteners passing through a region of overlap between adjacent side walls or the side walls of adjacent web sections may be welded to one another.
In one embodiment of the present invention the central walls include gusset sections which extend past the upper or lower edges of the side walls and the flanges are positioned between the gusset sections.
Preferably, the central walls have a strengthening structure comprising a channel or fold formed therein which extends between the upper and lower edges of the central walls.
Optionally, the central walls have holes defined therein.
The web sections may comprise steel, aluminium, plastics or composite material.
The present invention extends to a building element comprising:
two beams as defined and described hereinabove; and
a connector having two pairs of holding channels extending at an angle relative to each other, wherein parts of the flanges of each of the beams are received in a different pair of holding channels and fixed thereto.
The present invention also extends to a building element comprising:
a beam as defined and described hereinabove; and
a bracket having a pair of holding channels that receives ends of the first and second flanges.
By way of example only, preferred embodiments of the invention will be described more fully hereinafter with reference to the accompanying figures, wherein:
The present invention relates to improved beams and building elements, and methods of constructing them. Elements of the invention are illustrated in concise outline form in the drawings, showing only those specific details that are necessary to understanding the embodiments of the present invention, but so as not to clutter the disclosure with excessive detail that will be obvious to those of ordinary skill in the art in light of the present description.
In this patent specification, adjectives such as first and second, left and right, top and bottom, etc., are used solely to define one element or method step from another element or method step without necessarily requiring a specific relative position or sequence that is described by the adjectives. Words such as “comprises” or “includes” are not used to define an exclusive set of elements or method steps. Rather, such words merely define a minimum set of elements or method steps included in a particular embodiment of the present invention.
The first flange 16 and the second flange 18 are preferably made from a rectangular cross-section steel bar, however any other suitable material may be used. The first flange 16 comprises a front surface 20, a back surface 22, a bottom surface 24 and a top surface 26. The second flange 18 comprises a front surface 30, a back surface 32, a top surface 34 and a bottom surface 36. The second flange 18 is spaced substantially parallel to the first flange 16 and the bottom surface 24 of first flange 16 faces the top surface 34 of the second flange 18. The first and second flanges 16, 18 are of substantially equal length.
Each web 12 may be manufactured from a single plate of steel; however any other appropriate material may such as aluminium, plastic or composite materials may be used to create a series of rolled profiles as is known to a person skilled in the art.
The central wall 40 of one web 12 is co-planar with the front surfaces 20, 30 of the flanges 16, 18, respectively, and the central wall 40 of adjacent webs 12 are co-planar with the rear surfaces 22, 32 of the flanges 16,18 respectively. As such, the central walls 40 of adjacent webs 12 are spaced substantially parallel to each other and are transversely staggered relative to the central beam axis 50.
The beams 10, 100, 200, 300 can be used to create a variety of rafters, columns or other structural supports. Furthermore, arches can be manufactured by joining a plurality of beams 10, 10, 200, 300 using methods well known in the art such as welding or using connecting sections.
FIG's 8 to 12 will describe various connections that may be made to connect beams 10, 100, 200, 300 to construct a framework of a building.
The footplate 600 is secured to the footings of the building by having one end of the footplate concreted into a floor 606 of the building, as would be known to a person skilled in the art or using any other applicable securing means. The flanges 16, 18 of the proximal end of the beam 10 are mounted and mechanically secured inside the upwardly projecting holding channels 602 of the footplate 600.
The embodiments described within this specification generally describe manufacture using steel. It should be appreciated that steel may not be the only suitable material and that aluminium or any other suitable material, such as fibre-glass, plastic or any other high strength material may be used. Mechanical joins described may involve, for example, welding, bolting, screwing, gluing, riveting, or chemically bonding materials together.
Advantages of the present invention include enabling large structural beams to be assembled from compact and portable components. For example, the webs 12 can be stamped or rolled in large volumes and then compactly stacked and shipped to a construction site. Also, the flanges 16, 18 can be identical and thus can be efficiently manufactured in large volumes, by for example cold roll forming, and then shipped to a construction site where the beams 10 are assembled. Additionally, the strengthening structures, such as the structures 38, allow any moisture trapped between the composite web 14 and the flanges 16, 18 to drain from the webs 12, preventing corrosion or rust.
The above description of various embodiments of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art of the above teaching. Accordingly, while some alternative embodiments have been discussed specifically, other embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. Accordingly, this patent specification is intended to embrace all alternatives, modifications and variations of the present invention that have been discussed herein, and other embodiments that fall within the spirit and scope of the above described invention.
Number | Date | Country | Kind |
---|---|---|---|
2008901785 | Apr 2008 | AU | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/AU2009/000448 | 4/9/2009 | WO | 00 | 2/1/2011 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2009/124356 | 10/15/2009 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
1649577 | Coryell | Nov 1927 | A |
1975228 | Grumman | Oct 1931 | A |
2101090 | Palmer | Dec 1937 | A |
2205725 | Kavanagh | Jun 1940 | A |
2656999 | Ullberg, Jr. | Oct 1953 | A |
3300839 | Lichti | Jan 1967 | A |
3362056 | Preller et al. | Jan 1968 | A |
4147379 | Winslow | Apr 1979 | A |
4232845 | Turner | Nov 1980 | A |
4885892 | Gooding | Dec 1989 | A |
5165213 | Finch et al. | Nov 1992 | A |
5417022 | Ritchie | May 1995 | A |
5470021 | Looney | Nov 1995 | A |
5816012 | Willis | Oct 1998 | A |
6205725 | Butler | Mar 2001 | B1 |
6415577 | Curtis | Jul 2002 | B1 |
6826884 | Pabedinskas et al. | Dec 2004 | B2 |
7127862 | Saldana | Oct 2006 | B2 |
20070056246 | Escobar Benavides et al. | Mar 2007 | A1 |
Number | Date | Country |
---|---|---|
199676446 | Jun 1997 | AU |
1011092 | Nov 1965 | GB |
0034599 | Jun 2000 | WO |
2005042869 | May 2005 | WO |
Entry |
---|
International Preliminary Report on Patentability based on Australian Application No. PCT/AU2009/000448 dated Sep. 23, 2009. |
International Search Report based on Australian Application No. PCT/AU2009/000448 dated Jun. 9, 2009. |
Number | Date | Country | |
---|---|---|---|
20110113725 A1 | May 2011 | US |