GB2222188A - Structural framework - Google Patents

Abstract

A structural system utilises a generally C-section member 10 with side-recessing 16 therealong via which a length thereof is securable to ends of the other lengths that are inserted end on into the C-section with a 90 degree relative rotation about the longitudinal axis, to create structural frames comprising spaced horizontal as lengths of said members joined by spaced verticals also as length of said members. The two members are connected by bolts. A cover may be provided (Fig. 2, not shown). <IMAGE>

Description

Title: Structural System DESCRIPTION This invention relates to a structural system that finds use in walls of buildings having other primary structural support provisions, though not necessarily exclusively to such walls, and is specifically applicable to so-called secondary steelwork of steel and/or concrete framed buildings.

Requirements of such buildings often include window provisions of substantial horizontal extent, sometimes effectively as a band virtually about the building at each floor, and with alternating horizontal bands of wall that are clad externally and/or internally to particular design and taste.

Effectively, of course, such horizontal bands of wall serve to support each next-upwards band of window provisions, and should not unduly load lower bands of window provisions. Indeed, it is the purpose of the above-mentioned secondary steelwork to achieve such result, and it is normal to design and fabricate steel frames individually for each building, preferably with verticals to aid attachment of cladding, and usually with diagonals between horizontals connected by the verticals for strength and resistance to deflection.

Such designed fabrication is a high cost item of buildings.

We have investigated various alternatives as available from fabricators of steel beams and other frames, typically of a construction comprising upper and lower channel sectionsinterconnected by zig-zag bracing which may be bent up from stock rod or bar prior to welding to the channels alternately at bends.

Fabricators geared up to making such members can achieve good economy, and can further design and produce to specific requirements at quite reasonable costs. However, such constructions are not ideal for use in walls that will need cladding inside and/or exteriorly, often by panels that are best fitted with verticals at their sides to aid edge-to-edge or overlapping junctions.

It is an object of this invention to provide an alternative structural system having advantages.

According to this invention there is provided a structural system utilising a generally C-section member with side-recessing therealong via which a length thereof is securable to ends of other lengths that are inserted end-on into the C-section with a 90 degree relative rotation, structural frames then including spaced horizontals as lengths of said members joined by spaced verticals also as lengths of said member.

Such a system, using a particular said generally C-section member, will have known structural characteristics and is thus readily susceptible of easy specification and design to suit any particular requirement, including assessing and quantifying what, if any, additional verticals or subsidiary bracing is required after provisions are made to facilitate attachment of cladding panels butting together at specified verticals. Diagonals for bracing purposes may be of the same member or otherwise, in either case readily secured in top and bottom channel member lengths.

Side-recessing can conveniently be such as to extend from flanking surfaces affording flats for affixing cladding panels. Verticals can readily have their otherwise open faces flashed over by a cover plate or sheet, preferably itself bent to extend over sides of the C-section, even effectively then presenting an overall rectangular outer surface.

Side-recessing, particularly similarly along each side as is preferred, actually both contributes to strength and affords securement positions that are as conveniently occupied by bolts through registering holes as by welds. Optionality as to fabrication on site or at the factory is thus complete.

Specific implementation of this invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure 1 shows a section through a preferred structural member; Figure 2 shows a section through such a member with its opening closed; Figure 3 shows, diagrammatically, a structural frame using lengths of the members of Figures 1 and 2; Figures 4 and 5 show, diagrammatically, top joint details of Figure 3.

In the drawing, referring first to Figure 1, a preferred structural member 10 of generally C-section has a flat web 12 with substantially perpendicularly extending sides 14A, 14B each recessed at 16A, 16B to present a flat 18A, 18B extending along each side, and with substantially perpendicularly ends 20A, 20B returned parallel with the web 12. Overall, the section of the member 10 is longer (at X) across its web 12 than (at Y) down its sides 14A, 14B. The spacing of the flats 16A, 16B from each other interiorly of the section (at Z) will accommodate the dimension Y of the member 10 after covering with a flashing sheet or panel, see 22 in Figure 2, and facilitate relative securement through the flats 18A, 18B.In other words, the dimension Z is a little larger than Y by at least the thickness of the flashing sheet or panel 22 and with a tolerence consistant with achieving securement through the flats. Of course, the dimension Z may be such that there is a close, if not interference, fit by a flashed member 10 (Figure 2). An excess of the dimension Z over the dimension Y of about 2 mm is presently envisaged for a member 10 formed up from galvanised steel sheet of 2 to 2.4 mm thickness.

A preferred flashing sheet 22, see Figure 2, has a web 24 extending over the otherwise open face of the member 10 and has substantially perpendicularly extending sides 26A, 26B that can, and do as shown, extend over substantially the whole of the dimension Y but say, at least to cover over the recessings 16A, 16B.

The use of pre-galvanised, steel sheet for the member 10, also the flashed member 22, at least when fabricating frames (Figure 3) by bolting together, can be advantageous when compared with fabrication by welding that may require dipping of the entire frame.

Turning to Figure 3, a frame 30 of which at least top 32 and bottom 34 and verticals 36 are of structural members as in Figures 1 and 2.

In the detail of Figures 4 and 5, only frame parts 32 to 36 are of such members, diagonally parts 38 are of tension bars or rod type. Securement together using bolts is shown at 40, 42 for the verticals and horizontals and at 44 for the diagonals, bolt heads conveniently being in recess of the members hereof.

Claims (7)

1. A structural system utilising a generally C-section member with side-recessing therealong via which a length thereof is securable to ends of other lengths that are inserted end-on into the C-section with a 90 degree relative rotation, structural frames then including spaced horizontals as lengths of said members joined by spaced verticals also as lengths of said member.

2. A system as claimed in claim 1 in which side-recessing extends from flanking surfaces affording flats for affixing cladding panels.

3. A system as claimed in claim 1 or 2 in which said inserted other lengths have their otherweise open faces flashed over by a cover plate or sheet.

4. A system as claimed in claim 3 in which the cover plate is bent to extend over sides of the C-section.

5. A system as claimed in any one of claims 1 to 4 in which the side-recessing, particularly similarly along each side as is preferred, contributes to strength and affords securement positions.

6. A system as claimed in claim 5 in which the securement positions are occupied by bolts.

7. A structural system constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.