EP0106870A1 - Temporary floor, framework for supporting such a floor, and structural members constituting such a framework - Google Patents

Abstract

Laminated mild steel channel-shaped members, preferably reinforced by stamped grooves (9 and 10) and preferably having lips turned inwards (11) and lip edges turned downwards (12) can be fixed by welding (a) mouth to mouth to give a vertical frame support of box-shaped section and (b) back to back to give a horizontal beam of I-shaped section. The members can also be used simply as secondary horizontal beams. A mezzanine floor and similar temporary support structures can be constructed using such welded unitary members (to obtain a solid modular frame of attractive appearance), and suitable interconnecting members are also described.

Description

"TEMPORARY FLOOR, FRAMEWORK FOR SUPPORTING SUCH A FLOOR, AND STRUCTURAL MErøERS CONSTITUTING SUCH A FRAMEWORK"

This invention relates to a mezzanine floor or ^"Like temporary or semi -permanent support and storage platform, and to a framework suitable for supporting such a floor. It further relates. to a metal structural member of uniform profile and indefinite length, produced by cold-forming and particularly useful in the assembly} of such a framework structure.

The amount of available space in a warehouse is a function not only of the floor area but of the height to which the material in the warehouse can be safely stacked. Thus, for example, it is often not viable to stack cardboard boxes more than eight-high, since the pressure of the weight -of the column deforms or distorts the lower boxes with consequent damage and loss of contents.. Sim¬ ilar considerations apply to sacks of material. Thus, a particular design of warehouse may be inefficient for its temporary purpose, since it is not possible to convert a warehouse from storage of one form of goods to storage of another at short notice.

For this reason, it is occasionally desirable to incorporate into, a high enclosed space such as found in a warehouse an inter¬ mediate support floor for temporary or semi -permanent use. As an extension of this idea, the floor can be of a f nished appearance and constitute a floor to support partitioning and office-space. Again, it can be temporary staging supporting a

OMPI simple floor of abutting panels, for inspection or commissioning a large piece of plant.

There is thus a need in industry for a simple neat mezzanine structure to carry a load at a distance spaced above the floor of a given enclosure. A basic dilemma however is that normally use must either be made of building components which are made to last (so that erection of building components upon the floor is more expensive than the situation warrants and more difficult to remove afterwards) or of cheap and easily destroyable material (which giv€S a weak, and unattractive-looking structure).

The present invention sets out in one aspect to provide a modular framework of metallic members terminating at a common height, to support a floor which provides storage space or otherwise acts as a new floor. The invention accordingly consists in a framework to stand on a level surface, and having a defined upper level to support a floor and thereby provide storage space or a mezzanine floor or the like: the framework being composed essentially of a family of elongate structural members fastened together, all such members having an identical trans-verse cross-section, being generally that of a shallow channel with vertical walls: the family comprising a first plurality of .such members of length (a) fastened mouth-to- mouth in pairs to define a box-section, a second plurality of such members of length (b) fastened back- to-back in pairs to define an I-section, and a third plurality of such members of length (c) provided as individual members; wherein the box section pairs of length (a) are located as vertical supports, each at an intersection

OMPI of a rectilinear grid, of unit size (b) times (c), covering the desired area of the level surface; each I-section pair of length (b) runs horizontally and is supported, exhibiting its I-section vertically, at each of its ends at the top of a different one of said one vertical supports, with successive such I-section pairs having mutually opposed ends at the top of the same vertical support and all such pairs being parallel; and each structural member of length (c) also runs horizontally, all such members being mutually parallel and fixed at desired intervals at rtght- angles to I-section pairs with the base of the channel-section vertical.

For an appearance of neatness, the bases of the successive I-section pairs are received with their base-widths located across the identical widths of the box-section vertical support. Usually, the lengths (a), (b) and (c) are generally similar, that is to say, lie within a 2:1 overall ratio of any two such lengths. Preferably, the length (a) equals the length (b) and equals the length (c), since then the framework as described above, useful for a mezzanine floor or like support level, can be most , cheaply built from volume production of structural members having not only the same cross-section but also identical lengths.

Where the structural members are arranged in pairs, that is to say, either as a box-section or as an I-section, .they can be welded for union at the outermost of the contacting edges. To facilitate such uniting in pairs it is envisaged that the channel section, as well, as presenting a base (or web) and a pair of shorter parallel vertical walls (or flanges) usually of a height less than half the base width can also present an integral inwardly turned lip as an extension of the flange and lying parallel to the web. Preferably, moreover, there is a further inwardly turned edge to this lip, so as in this instance to lie parallel to the flange. It will be found that structural members made in this especially if radiused on corners and edges in a conventional fashion can be readily united mouth-to-mouth or back-to-back and still preserve a neat appearance free from rough edges.

Such structural members are variously arranged in the framework to lie vertically or horizontally. They are thus under different types of stress in use, being for example under compression (the verticals), or buckling or bowing stress (the horizontals) or possibly under torsional effects (especially if any part of the structure is unevenly loaded). To resist these effects, it has been found preferable if the outside base or web of the channel possesses one or more but preferably two parallel swaged grooves or recesses, deforming the thickness of the material so as to present complement¬ ary raised ribs within the channel, and extending along the whole length of the member. Generally speaking, these grooves are of arcuate, e.g. part circular, cross-section. Such grooves exert a restraining effect against deformation arising from stress during use.

From the foregoing, it will be apparent that a preferred type of structural member for use in this framework is a metal structural member of uniform cross-section of which exhibits a v/eb or base and integral parallel upstanding walls or flanges extending the same side of the base at each edge thereof and at an angle essent¬ ially of 90°, the combined lengths of the walls being less than the width of the base, wherein one or more grooves are swaged into the base so as to deform the thickness of the material and produce a complementary rib on the inside of the channel, and so as to extend along the whole length thereof..

Preferably, in the structural member, two such grooves are swaged into the base, usually being equally spaced about its mid-point. Preferably the grooves are arcuate (most preferably part-circular) in cross-section. Needless to say, the ribs deformed on the inside of the base will also effectively have almost the same section since the effect of swaging is to deform the material throughout its thickness. We have found that a structural member formed in this way has good resistance to torsional compressional and buckling deformation.

Further preferred features of this form of structural member are located at the free outer edge of the walls. Preferably the free edge of the wall, or flange, is in each case turned inwardly at 90° i.e. so as to run parallel to the web or base as a lip.

Preferably, moreover, this lip is itself turned inwardly at its free edge i.e. so as to run parallel to the wall, in each case. These preferred features have the effect of providing a smooth turned corner at each external angle; these corners can be suitably radiused as well known in- this art. While the dimensions of the section according to the invention are not of themselves critical, it will be found preferable if the section, if made of say two millimetre thick mild steel, is from 150 to 300, preferably 200 to 250 millimetres external .base width, and from 50 to 100, preferably 60 to 80, millimetres wall height. The swaged grooves can be 40 to 80 millimetres apart at their mid-points, but are preferably between 50 to 70 millimetres apart. The grooves can be for example of 20 to 40 millimetres, preferably between 25 and 35 millimetres, across their opening, and deformation, that is to say, the depth of the grooves, can preferably be from 50 to 10 millimetres, preferably 8 millimetres.

Under these c rcumstances, a part-circular groove having a radius for example 10 to 15 centimetres, preferably about 12 millimetres, can be envisaged.

The inturned flange, parallel to the base, have a dimension from 10 to 20 millimetres, preferably 12 to 18. The inwardly turned edge on this lip or flange can be quite small, having a dimension from 5 to 15 millimetres but preferably between 8 and 12 millimetres.

Interconnection of the structural members, whether themselves pre-united in pairs or used as a single member, can be considered n two forms.

The simpler form is the interconnection only of two horizontal members, tht is to say, the I-section pair and the single channel section which takes place between the vertical supports. For this purpose, it is preferred to provide a generally right-angled member attached at one limb e.g. by bolting or riveting to the inside of the individual channel and at the other limb inside of one of the channels of the I-section. Such a member while generally flat can itself be shaped so as to fit snugly over the swaged grooves, 5 if these are present.

The other form of interconnection is for use where the two types of horizontal member meet at the top of a vertical box-section pair. Such a connecting member can be formed of sheet material welded to a generally cruciform shape, exhibiting four plate-like 0 portions at right angles each with a downward coplanar extension at its ourter margins: the first two of the plate-like portions being flat and coplanar (preferably being. the two halves of a single plate) each for accommodation and attachment between the two webs of I-section pairs, and the second two plate-like portions 5 each being attached, in essentially the same plane, at right angles to the first two portions each for attachment to the outside of the base of an individual structural member at one end thereof with the downward extensions embracing and fixed to the top of the box-section vertical support. Preferably for this purpose the extensions on the 20. first two plate-like portions contact the box-section vertical support at the mid-pόint of the short dimension thereof (i.e. where the individual member are joined mouth-to-mouth) and the second two extensions contact such support at the mid-point of the long dimension (i.e. the base of the channel). One or other such pair 5 of extensions, preferably the second, may possess a flattened right-angle portion for attachment by welding to the exterior of the upper portion of the box section.

The second plate-like portions can each be suitably deformed to accommodate any swaged grooves on the base of the individually- utilized structural members. Preferably, each such plate-like portion is so deformed that it will accommodate and mate with one such swaged groove whichever way around the individual channel 5 portion is placed, this refinement allows the framework to be neatly terminated at either lateral edge.

For convenience and safety the box-section member can be held at its lower extremity in a complementary hole in a case plate secured to the ground. ^'10 In addition to all the above features, it is also envisaged to utilize additional stiffening and strengthening horizontal members, fixed between those structural members which are used individually, so as to provide a good support for an overlying floor. These additional horizontal members can be of a considerable smaller 15 cross-section, and in fact are preferably of a deep channel section used with the base of the channel uppermost.

Although the invention has been defined in relation to the framework the finished mezzanine floor itself also constitutes an aspect of the invention. 20 The invention will be further described with reference to the accompanying drawings in which :-

Figure 1 shows a support framework for a mezzanine floor in plan view;

Figure 2 shows the framework of Figure 1 in side view; 25 Figure 3 shows on a larger scale a section III - III of

Figure 1;

Figure 4 shows a section IV - IV of Figure 3;

Figure 5 shows on a larger scale a section V - V of Figure 1: Figure 6 is a plan view of Figure 5;

Figure 7 is a plan view of a base plate to accommodate the lower end of a box-section upright; and

Figure 8 shows in isolation a uniform section of the preferred form of structural member in mild steel.

The framework shown in Figures 1 and 2 is composed essentially of a number of identical structural members, fixed together at their ends. Each structural member has the same length with the same^' uniform section typically a mild-steel channel having a generally flat base with a pair of integral vertical parallel walls, less than half the base width, along each edge, a preferred detailed form of such channel being discussed in more detail below.

These structural members are either used as horizontal members singly as at A; or joined back- to-back as at B to give an I-section horizontal member at right angles to A; or joined mouth-to-mouth as at C (Figure 2) to give a box-section vertical member arranged at the corners of a square grid. They are joined by interconnect¬ ions 2 (see also Figure 3) and 3, where all three versions A, B and C join. The lower ends of combination C, i.e. the box-section vert- ical are each held in a base plate 4 (see Figure 7) secured to the existing floor 5. The. framework is completed by small-section bars as at 6, typically themselves of deep channel section and used base uppermost and which can be utilized at as close a spacing as desired, four bars 6 between each horizontal pair B being generally envisaged. Figure 3, being a section III - III of Figure 1 effectively shows the form of interconnection 2, and is to be considered along with Figure 4.

Before discussing the interconnection in detail however, it will be convenient to describe a preferred form of structural member cross-section, shown in isolation in Figure 8, to which however the- present invention in its broad form is not limited.

Each such preferred section is a channel with a generally flat base 7 and integral vertical side walls 8. Base 7 possesses two parallel swaged recesses 9 and 10 deforming the thickness of the material so as to appear as ribs inside the channel and of part- circular cross-section, such swaged ribs extending the length of the structural member as a buckling-bending-, or torsion-resistant conformation. Each side wall 8 has an inwardly turned lip 11, parallel to the base, and each lip an inwardly turned edge 12 parallel to the walls. The various external corners presented are suitably radiused, since a preferred form of fabrication of the structural member is by cold- forming, i.e. progressive deformation without applied heat, of a metal strip. Specific dimensions, given by way of example, are as follows:-

Base width - overall 220 millimetres.

Wall height - overall 65 millimetres.

Lip width - overall 60 millimetres.

Inturned edge depth - overall 10 millimetres. Groove spacing to mid-point 60 millimetres (grooves are symmetrically arranged about the mid-point of the base).

Groove depth 8 millimetres.

Material thickness 2 millimetres. To return now to the interconnection, the I-beam pair B is arranged with its I-section vertical, and two individually used members A are brought up one to each side, at right angles. Right angled interconnection pieces 13, with complementary swaging 14 to fit over the ribs inside the channels are then attached individually to each end of the members A by bolts or rivets 15 and jointly to the I-section pair B by bolts or rivets 16. It is to be noted how lip 11 and inturned edge 12 can provide snug location to the interconnect on pieces 13, and- a neat appearance to the interconnect- ion 2.

Figure 5, being a section V - V of Figure 1, effectively shows the form of interconnection 3, and is to be considered along with Figure 6, the preferred form of section again being used as shown for example in Figure 3. In Figure 5, the upper end 16 of an assembly C, box-shaped in cross-section supports mutually opposed ends 17 and 18 of two succ¬ essive I-section assemblies B with a small gap 19 between them. At end 18 there is located .at right angles, two individually used structural members C, see also Figure 6, with their bases aligned in a plane passing through gap 19. This arrangement is secured together by a generally cruciform sheet metal member 20 exhibiting four plate-like portions 21, 22, 23 and 24 mutually at right-angles, each with a coplanar extension 25, 26, 27 and 28 at its outer margin. Plate-like portions.21 and 22, in the embodiment shown are in fact two halves of a single plate and are accommodated and fixed by bolts or rivets 29 between the two webs of the I-section at 17 and 18. Plate-like portions 23 and 24 are generally coplanar, pass through gap 19 and bolt and rivet and 30 to the outside of the bases,

- TJR of the two channel members indiyi dually used at C. These plate¬ like portions 23 and 24 are swaged with recesses complementary to those of the bases of the channels, if these recesses open one to each surface of the plate-l ke portions 23 and 24 then the member as at C can attach either way round e.g. to finish a lateral edge of a mezzanine floor neatly.

The downward extensions 25 - 28 jointly define a rectangular space embracing the top 16 of the vertical support. These extensions 25, 26 are triangular in shape, as shown and are welded in their internal edges to the joining line of the box-section.

Extension 27, 28 while ^"possessing a like triangular portion, not shown in detail, each further possess a flattened right-angle portion

27a and 28a for attachment^' by welding to the wider face of the box-section. Figure 7, as already mentioned, shows a base plate 31 attached to a concrete floor by fixing bolts 32 and possessing a suitably shaped recess 33 for holding the box-section formed by mouth-to- mouth welding of two members 1.

Figure 8 is already described in detail above.

Claims

1. A framework to stand on a level surface, and having a defined upper level to support a floor and thereby provide storage space or a mezzanine floor or the like: the framework being composed essent¬ ially of a family of elongate structural members fastened together, all such members having an identical transverse cross-section, being generally that of a shallow channel with vertical walls: the family comprising a first plurality of such members of length (a) fastened mouth-to-mouth in pairs to define a box-section, a second plurality of such members of length (b) fastened back- to-back in pairs to define an I-section, and a third plurality of such members of length (c) provided as individual members; wherein the box section pairs of length (a) are located as vertical supports, each at an intersection of a rectilinear grid, of unit size (b) times (c), covering the desired area of the level surface; each I-section pair of length (b) runs horizontally and is supported, exhibiting its I-section vertic¬ ally, at each of its ends at the top of a different one of said one vertical supports, with successive such I-section pairs having mutually opposed ends at the top of the same vertical support and all such pairs being parallel; and each structural member of length (c) also runs horizontally, all such members being mutually parallel and fixed at desired intervals at right-angles to I-section pairs with the base of the channel-section vertical.

2. A framework as claimed in claim 1 in which the bases of the successive I-section pairs are received with their base widths located across the identical widths of the box-section vertical support.

OMPI

3. A framework as claimed in claim 1 or 2 in which the lengths of (a), (b) and (c)_:each lie within a 2:1 overall ratio of any two such lengths.

4. A framework as claimed in claim 3 in which the length of (a)

equals the length of (b). and equals the length of (c) .

5. A framework as claimed in any one preceding claim in which the pairs of structural members (a) and (b) are welded in each case at the outermost of their contacting edges.

6. A framework as claimed in any one preceding claim in which the channel walls (flanges) are each less than half as High as the base (web) is wide, and each have an inwardly turned outer lip.

7. A framework as claimed in claim 6 in which each such lip has an edge turned towards the base.

8. A framework as claimed in any one of claims 1 to 7 in which the outside base or web of the channel possesses one or more parallel swaged grooves or recesses deforming the thickness of the material so as to present complementary raised ribs within the channel, and extending along the whole length of the member.

9. A framework as claimed in any one preceding claim in which, for interconnection of the I-section pair and the single channel section there is provided a generally right-angled member attached at one limb e_Λg. by bolting or riveting to the inside of the individual channel and at the other limb inside of one of the channels of the

I-section.

10. A framework as claimed in any one preceding claim in which, for interconnection where the two types of horizontal member meet at the top of a vertical box-section pair, there is provied a connecting member formed of sheet material welded to a generally cruciform shape, exhibiting four plate-like portions at right angles each with a downward coplanar extension at its outer margins: the first two of the plate-like portions being flat and coplanar (preferably being the two halves of a single plate) each for accommodati on and attach¬ ment between the two webs of I-section pairs, and the second two plate.-! ike portions each being attached, in essentially the same plane, at right angles to the first two portions each for attachment to the outside of the base of an individual structural member at one end thereof with the downward extensions embracing and fixed to the top of the box-section vertical support.

T1. A framework as claimed in claim 10 in which the extensions on the first two plate-like portions contact the box-section vertical support at the mid-point of the short dimension thereof (i.e. where the individual member are joined mouth-to-mouth) and the second two extensions contact such support at the mid-point of the long dimen¬ sion (i.e. the base of the channel).

12. A framework as claimed in claim 10 or 11 in which one pair of extensions possesses a flattened right-angle portion for attach- ent by welding to the exterior of the upper portion of the box section.

13. A framework as claimed in claim 10, 11 or 12 in which each plate-like portion is so deformed that it will accommodate and mate with one such swaged groove whichever way around the individual channel portion is placed.

14. A framework as claimed in any one preceding claim further comprising additional stiffening and strengthening horizontal members, fixed between those structural members which are used individually, so as to provide a good support for an overlying floor.

15. A framework as claimed in claim 1 substantially as herein described with reference to the accompanying drawings.

16. A mezzanine floor incorporating a framework as claimed in any one preceding claim.

17. A metal structural member of uniform cross-section and indefinite length, the cross-section of which exhibits a web or base and integral parallel upstanding walls or flanges extending the same side of the base at each edge thereof and at an angle essentially of 90°, the combined lengths of the walls being less that the width of the base, wherein one or more grooves are swaged into the base so as to ^' deform the thickness of the material and produce a complementary rib on the inside of the channel, and so as to extend along the whole length thereof.

18. A structural member as claimed in claim 17 having two such grooves swaged into the base.

19. A structural member as claimed in claim 18 wherein the two grooves are equally spaced about the midpoint of the base.

20. A structural member as claimed in any one of the preceding claims 17 to 19 in which the free edge of the wall, or flange, is in each case turned inward at 90° as a lip parallel to the base.

21. A structural member as claimed in claim 20 in which the edge of each lip is turned inwardly through 90° to run parallel to the wall.

22. A structural member as claimed in any of claims 17 to 21 of from 150- to 300 mm external base width and 50 to 100 mm wall height; and of groove width from 20 to 40 ram and groove depth from 5 to 10 mm.

23. A structural member as claimed in claim 22 of from 200 to 250 ram external base width and 60 to 80 mm wall height; and of a groove width 25 to 35 mm.

24. A structural member as claimed in claim 22 or 23 as dependent on claim 21, in which each lip is from 10 to 20 mm wide with its inturned edge from 5 to 15 mm wide.

25. A structural member as claimed in. claim 24 in which each lip is from 12 to 18 mm wide with its inturned edge from 8 to 12 mm wide..

26. A structural member as claimed in claim 17 and substantially

1

OM as herein described with reference to Fig. 8 of the accompanying drawings.