GB2490928A

GB2490928A - Single leaf lintel

Info

Publication number: GB2490928A
Application number: GB1108341.7A
Authority: GB
Inventors: Sean Coyle
Original assignee: Keystone Lintels Ltd
Current assignee: Keystone Lintels Ltd
Priority date: 2011-05-18
Filing date: 2011-05-18
Publication date: 2012-11-21
Anticipated expiration: 2031-05-18
Also published as: GB2490928B; GB201108341D0

Abstract

The lintel 1 has a generally L-shaped section and comprises a foot member 2 and a leg member 3, the leg member comprising a reinforcing formation 5 to increase itâ s resistance to buckling. The reinforcing formation may comprise additional material at the end of the leg member 6 which may comprise an increased wall thickness or a bulb of material extending along part or all of the length of the leg member. The additional material may be integrally formed with the leg member. The reinforcing formation may comprise an elongate protrusion 11 extending away from the free end of the leg member. The protrusion may comprise rectilinear, non rectilinear or arcuate stiffening members. The reinforcing formation may comprise an L-shaped attachment that may be coupled to the lintel. Preferably the lintel is manufactured from steel. Also claimed is insulation material having a recess to receive a protrusion from a lintel.

Description

A LINTEL

The present invention relates to a lintel and in particular to a single leaf reinforced steel lintel with improved structural performance for supporting masonry.

Lintels are the standard means by which masonry and building structures are supported above openings in masonry walls. Single leaf steel lintels are generally made with C section or L section profile. The C section is stronger because the shape and configuration of the C-section is more resilient to web buckling. However, the top flange creates a problem in that the top flange must be accommodated within the masonry. Masonry must be cut or arranged in course to fit within the channel causing major disruption to the efficiency of the building process. The L section is not as strong but is obviously less disruptive to the building process. Traditionally the L section receives a bend B towards the upper end UE of the substantially vertical web V as shown in Figure A. This bend B adds stiffness and hence additional flexural rigidity whilst retaining the advantage of avoiding a top flange protruding substantially orthogonally from the Vertical web towards the masonry as is the case in the C-section lintel.

An alternative solution to this problem is shown in Figure B where the L-shaped lintel is manufactured from a thicker sheet S of steel. However, the thicker sheet S of steel material adds cost to the product and is a major disadvantage in the current economic climate where the price of steel/metal is steadily on the rise. When combined with negative pressure on the commercial value of property, adding costs to the building components is unattractive to everyone involved in the construction sector as well as everyone involved in the commercial trade of property.

With reference to Figure C, it is shown that the critical stress in an L section lintel L under loading in use occurs proximal to the top portion T of the vertical web V at or about the upper edge E of the vertical web V of the L-shaped lintel in use. This critical stress causes this upper portion of the vertical web V to buckle as shown by dotted lines D thereby significantly effecting the mechanical properties of the L section lintel and potentially effecting the structural integrity of the wall housing the L section lintel L. As explained above, this is preferably a slender web component designed to minimize cost.

Until recently, the use of top hat section lintels has been prevalent over openings in cavity walls and has reduced the requirement for single skin lintels therefore a minimum amount of development of single skin lintels has occurred in the construction industry for almost 50 years. In recent times, the gap in a cavity wall has increased which means that additional steel material is required to bridge the gap leading to a significant increase in the cost of the top hat section steel lintel. Furthermore, the focus of the building sector on energy efficient building technologies has also highlighted the cold bridging effect of the top hat section lintel and lintels in general.

It is an object of the present invention to improve the strength of a generally L section lintel by increasing the resistance of the generally L section lintel to buckling.

Accordingly, the present invention provides a generally L section lintel comprising a foot member for supporting masonry thereon and a leg member having one end extending from the foot member, the leg member having means for increasing resistance to buckling comprising an enhanced reinforcing material formation with a greater resistance to buckling than a single bend.

Preferably, the leg member having means for increasing resistance to buckling at or about the other end distal to the foot member.

Ideally, the enhanced reinforcing material formation comprises additional material at or about at least part of the other end of the leg member.

Advantageously, the enhanced reinforcing material formation for increasing resistance to buckling provides alternative means to the prior art single elongate bend along the upper portion of the leg member. The enhanced reinforcing material formation at or about the free end of the leg member also provides an alternative to increasing the overall thickness of the entire length of the L section lintel significantly reducing the material required. The enhanced reinforcing material formation increases horizontal restraint along the upper edge of the leg member web by increasing the flexural rigidity of the leg member.

The enhanced reinforcing material formation is applied along at least part of the free end of the leg member where it is most effective to mitigate against web buckling. Advantageously, the enhanced reinforcing material formation increases the resistance to buckling of the upper portion of the leg member and thereby improves the overall performance of the L section single leaf lintel.

Ideally, the additional material comprises an increased wall thickness of material along at least part of the length of the other end of the leg member distal to the foot member.

Advantageously, the increased wall thickness provides greater strength to the upper portion of the leg member preventing web buckling of the L section lintel under loading.

Preferably, the additional material comprises an increased wall thickness of material along the length of the other end of the leg member distal to the foot member.

Ideally, the additional material comprises a bulb of material extending along at least part of the length of the free end of the leg member.

Preferably, the additional material comprises a bulb of material extending along the length of the free end of the leg member.

Ideally, the additional material comprises a beam of material extending along at least part or all of the length of the free end of the leg member.

Ideally, the additional material is integrally formed with the leg member.

Advantageously, the additional material can be roll formed into the lintel during the normal roll forming process.

Preferably, the enhanced reinforcing material formation comprises an elongate protrusion extending away from at least part of or all of the length of the free end of the leg member initially in a direction away from masonry mountable on the foot member.

Ideally, the elongate protrusion comprising more than one plane.

Preferably, the elongate protrusion comprising more than one stiffening bend defining at least two rectilinear elongate stiffening members. Advantageously, the two or more stiffening bends increase the flexural rigidity of the free end of the leg member of the L section lintel.

Ideally, the elongate protrusion comprising a non rectilinear member.

Preferably, the non rectilinear member comprises an elongate arcuate member.

Advantageously, the increased resistance to buckling provided by the non rectilinear member is greater than the increased resistance to buckling provided by the rectilinear bent

section of the prior art.

Preferably, the non rectilinear member for increasing resistance to buckling protrudes from at least part of or all of the free end of the leg member in a direction initially away from the masonry mountable on the foot member.

Ideally, the non rectilinear member curves back towards the leg member.

to Alternatively, the enhanced reinforcing material formation comprises an elongate attachment member. Advantageously, the elongate attachment member can be welded to the free end of L section lintel during or after forming. Additionally, the attachment members can be retrospectively fitted to in-situ lintels during reconstruction or after fire damage.

In an alternative arrangement, a plurality of attachment members are mechanically coupled to the free end of the L section lintel in a spaced apart relationship.

Ideally, the attachment member is an L shaped elongate member.

Preferably, one leg of the elongate attachment member rests in a face to face configuration with an upper surface of the leg member and the other leg of the attachment member protrudes substantially orthogonally away from the leg member.

Preferably, the lintel is manufactured from steel.

Ideally, the attachment member is manufactured from steel. Alternatively, the attachment member can be manufactured from metals, metal alloys or other rigid materials with a high flexural rigidity suitable for use to prevent buckling of steel Iintels.

Preferably, an inverted cap, most preferably u-shaped is attached to the free/upper end of the leg member.

According to a further aspect of the invention, there is provided an insulation means having at least one recess formed for receiving a protrusion from a leg member of a single leaf lintel.

Ideally, the lintel is a generally L section lintel.

Preferably, the recess is formed for receiving an enhanced reinforcing material formation of a generally L section lintel as outlined above.

Ideally, the insulation means comprises a recess on two opposing outside surfaces of the insulation means.

Preferably, the insulation means comprises a block of insulation material used in the construction industry.

Ideally, the one or more recess is formed for receiving the leg member and the protrusion from a leg member of a single leaf lintel.

Ideally, the one or more recess is formed for receiving the leg member and the enhanced reinforcing material formation.

The invention will now be described with reference to the accompanying drawings which shows by way of example nine embodiments of an L section lintel in accordance with the invention. In the drawings: is Figure A is an end view of a prior art generally L section single leaf lintel; Figure B is an end view of a second embodiment of prior art L section single leaf lintel; Figure C is a perspective view of a third embodiment of L section single leaf lintel showing a schematic view of web buckling; Figure 1 is an end view of a first embodiment of a generally L section single leaf lintel in accordance with the invention; Figure 2 is an end view of a second embodiment of a generally L section single leaf lintel; Figure 3 is an end view of a third embodiment of a generally L section single leaf lintel; Figure 4 is a vertical section through a cavity wall showing two third embodiment generally L section single leaf Iintels in position in a wall; Figure 5 is an end view of a fourth embodiment of a generally L section single leaf lintel; Figure 6 is an end view of a fifth embodiment of a generally L section single leaf lintel; Figure 7 is an end view of a sixth embodiment of a generally L section single leaf lintel; Figure 8 is an end view of a seventh embodiment of a generally L section single leaf lintel; Figure 9 is an end view of an eight embodiment of a generally L section single leaf lintel; and Figure 10 is an end view of a ninth embodiment of a generally L section single leaf lintel.

In Figures 1 to 9 of the drawings, there is shown a generally L section single leaf lintel indicated generally by the reference numeral I for increasing the flexural rigidity of the upright web section of the lintel 1. The lintel I has a foot member 2 for carrying masonry 20, 21 see Figure 4 thereon and a leg member 3 having one end 4 extending from the foot member 2. The leg member 3 has an arrangement 5 for increasing resistance to buckling at or about the other end 6 distal to the foot member 2. The arrangement 5 for increasing resistance to buckling comprising an enhanced reinforcing material formation at or about at least part of the other end or free end 6 of the leg member 3.

Advantageously, the enhanced reinforcing material formationJor increasing resistance to buckling provides an alternative arrangement to the prior art single elongate bend B along the upper portion UF of the vertical leg member V as shown in Figure A. The enhanced reinforcing material formation at or about the free end 6 of the leg member 3 also provides an alternative to increasing the overall thickness of the entire length of the L section lintel as shown in Figure B, significantly reducing the material required and cost. The enhanced reinforcing material formation increases horizontal restraint along the upper edge of the leg member web 3 by increasing the flexural rigidity of the leg member 3. The enhanced reinforcing material formation is applied along at least part of the free end 6 of the leg member 3 where it is most effective to mitigate against web buckling. Advantageously, the enhanced reinforcing material formation increases the resistance to buckling of the upper portion of the leg member 3 and thereby improves the overall performance of the L section single leaf lintel 1.

The enhanced reinforcing material formation comprises an increased wall thickness of material along at least part of the length of the other end 6 of the leg member 3 distal to the foot member 2, see figures 3, 7, 8, 9 and 10. Advantageously, the increased wall thickness provides greater flexural rigidity to the upper portion of the leg member 3 preventing web buckling of the L section lintel I under loading. The additional material comprises an elongate bulb of material 5 see figure 7 or a beam 5 of material see Figure 8 extending along at least part of the length of the free end 6 of the leg member 3. The enhanced reinforcing material formation is integrally formed with the leg member 3.

Advantageously, the additional material can be roll formed into the lintel 1 during the normal roll forming process.

The enhanced reinforcing material formation comprises an elongate protrusion 11 extending away from at least part of the length of the free end 6 of the leg member 3 in a direction initially away from masonry 20, 21 see Figures 1, 4, 5 and 6 mounted on the foot member 2. The elongate protrusion 11 comprises more than one plane. In Figure 1, 5 and 6, the elongate protrusion 11 comprises a first rectilinear elongate planar element 12 extending substantially orthogonally away from the leg member 3 in a direction opposite to the foot member 2. A second rectilinear elongate planar element 14 extends substantially orthogonally away from element 12 in a direction substantially parallel to leg member 3. In Figure 1, a further optional elongate L section elongate member 15 is shown in broken lines extending from the end of the second member 14 for providing additional flexural rigidity to the lintel 1. In Figure 6, a third member 13 extends from the second member 14 in a direction back towards the leg member 3. The elongate protrusion 11 of Figures 1, 5 and Figure 6 having two or optionally three stiffening bends 17, 18 and 19 defining the two or three

S

rectilinear elongate stiffening members 12, 13, 14. Advantageously, the two or more stiffening bends 17 to 19 increase the flexural rigidity of the free end 6 of the leg member 3 of the L section lintel 1.

Referring to Figure 2, the elongate protrusion 11 is a non rectilinear member 23 comprising an elongate arcuate member 23. Advantageously, the increased resistance to buckling provided by the non rectilinear member 23 is greater than the increased resistance to buckling provided by the rectilinear bent section of the prior art lintel shown in Figure A. The non rectilinear member 23 for increasing resistance to buckling protrudes from at least pad of the free end 6 of the leg member 3 in a direction initially away from the masonry 42, 43 mounted on the foot member 2 and curves back towards the leg member 3.

In an alternative arrangement shown in Figure 3, the enhanced reinforcing material formation is provided by an attachment member 25. Advantageously, the attachment member 25 can be welded to the free 6 end of the leg member 3 of the L section lintel I when they are formed. Additionally, the attachment member 25 can be retrospectively fitted to in-situ lintels 1 during reconstruction or after fire damage. The attachment member 25 is an L shaped elongate member 25. The lintels I are manufactured from steel and the attachment member 25 is manufactured from steel. One leg 28 of the elongate attachment member 25 rests in a face to face configuration with an upper surface of the leg member 3 and the other leg 29 of the attachment member protrudes substantially orthogonally away from the leg member 3 into an insulation material, see Figure 4. In the embodiment shown in Figure 10, the same attachment member 25 is attached to a bent end section 31 of the lintel 1. A further embodiment is shown in Figure 9 where an inverted u-shaped cap 32 is attached on the free/upper end 6 of the leg member 3.

Referring to Figure 4, there is show a vertical section of a cavity wall 41 having a generally L section lintel I located across an opening on the external skin of bricks 42 and a generally L section lintel 1 located across an opening on the internal skin of blocks 43. Each lintel I has an attachment member 25 in the form of an elongate L shaped attachment member 25 attached to the free end 6 of the leg member 3 of the lintel 1. One leg 28 of the elongate attachment member 25 rests in a face to face configuration with an upper surface of the leg member 3 and the other leg 29 of the attachment member 25 protrudes substantially orthogonally away from the leg member 3 into a specially designed block of insulation material 44 mounted between the blocks 43 and bricks 42. The insulation material 44 is formed for receiving the leg member 3 and protruding leg 29 of the attachment member 25. It will of course be appreciated that any of the embodiments of the lintel I described in the specification can be used on either or both skins of the cavity wall 41.

In relation to the detailed description of the different embodiments of the invention, it will be understood that one or more technical features of one embodiment can be used in combination with one or more technical features of any other embodiment where the transferred use of the one or more technical features would be immediately apparent to a person of ordinary skill in the art to carry out a similar function in a similar way on the other embodiment.

In the preceding discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of the said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

The features disclosed in the foregoing description or the following drawings, expressed in their specific forms or in terms of a means for performing a disclosed function, or a method or a process of attaining the disclosed result, as appropriate, may separately, or in any combination of such features be utilised for realising the invention in diverse forms thereof.

Claims

CLAIMS1. A generally L section lintel comprising a foot member for supporting masonry thereon and a leg member having one end extending from the foot member, the leg member having means for increasing resistance to buckling comprising an enhanced S reinforcing material formation with a greater resistance to buckling than a single bend.
2. A generally L section lintel as claimed in claim 1, wherein the leg member has means for increasing resistance to buckling at or about the other end distal to the foot member.
3. A generally L section lintel as claimed in claim I or claim 2, wherein the enhanced reinforcing material formation comprises additional material at or about at least part of the other end of the leg member.
4. A generally L section lintel as claimed in any one of the preceding claims, wherein the enhanced reinforcing material formation increases horizontal restraint along an upper r edge of the leg member web by increasing the flexural rigidity of the leg member.LU0 15
5. A generally L section lintel as claimed in any one of the preceding claims, wherein the enhanced reinforcing material formation increases the resistance to buckling of the upper portion of the leg member.
6. A generally L section lintel as claimed in any one of the preceding claims, wherein the additional material comprises an increased wall thickness of material along at least part of the length of the other end of the leg member distal to the foot member.
7. A generally L section lintel as claimed in claim 6, wherein the additional material comprises an increased wall thickness of material along the length of the other end of the leg member distal to the foot member.
8. A generally L section lintel as claimed in claim 6 or claim 7, wherein the additional material comprises a bulb of material extending along at least part of the length of the free end of the leg member.
9. A generally L section lintel as claimed in claim 8, wherein the additional material comprises a bulb of material extending along the length of the free end of the leg member.
10. A generally L section lintel as claimed in any one of claims 3 to 7, wherein the additional material comprises a beam of material extending along at least part or all of the length of the free end of the leg member.
11. A generally L section lintel as claimed in claim 10, wherein the additional material is integrally formed with the leg member.
12. A generally L section lintel as claimed in any one of the preceding claims, wherein the enhanced reinforcing material formation comprises an elongate protrusion extending away from at least part of or all of the length of the free end of the leg member initially in a direction away from masonry mountable on the foot member.
13. A generally L section lintel as claimed in claim 12, wherein the elongate protrusion r comprises more than one plane.LU14. A generally L section lintel as claimed in claim 12 or claim 13, wherein the elongate protrusion comprises more than one stiffening bend defining at least two rectilinear r elongate stiffening members.15. A generally L section lintel as claimed in claim 12, wherein the elongate protrusion comprises a non rectilinear member.16. A generally L section lintel as claimed in claim 15, wherein the non rectilinear member comprises an elongate arcuate member.17. A generally L section lintel as claimed in claim 15 or 16, wherein the non rectilinear member for increasing resistance to buckling protrudes from at least part of or all of the free end of the leg member in a direction initially away from the masonry mountable on the foot member.18. A generally L section lintel as claimed in claim 17, wherein the non rectilinear member curves back towards the leg member.19. A generally L section lintel as claimed in any one of the preceding claims, wherein the enhanced reinforcing material formation comprises an elongate attachment member.20. A generally L section lintel as claimed in claim 19, wherein a plurality of attachment members are mechanically coupled to the free end of the L section lintel in a spaced apart relationship.21. A generally L section lintel as claimed in claim 19 or claim 20, wherein the attachment member is an L shaped elongate member.22. A generally L section lintel as claimed in any one of claims 19 to 21, wherein one leg of the elongate attachment member rests in a face to face configuration with an upper surface of the leg member and the other leg of the attachment member protrudes substantially orthogonally away from the leg member.23. A generally L section lintel as claimed in any one of the preceding claims, wherein the lintel is manufactured from steel. r24. A generally L section lintel as claimed in any one of claims 19 to 23, wherein theLU0 15 attachment member is manufactured from steel, metals, metal alloys or other rigid materials with a high flexural rigidity suitable for use to prevent buckling of steel r lintels.25. A generally L section lintel as claimed in any one of the preceding claims, wherein an inverted cap, most preferably u-shaped is attached to the free/upper end of the leg member.26. An insulation means having at least one recess formed for receiving a protrusion from a leg member of a single leaf lintel.27. An insulation means as claimed in claim 26, wherein the lintel is a generally L section lintel.28. An insulation means as claimed in claim 26 or claim 27, wherein the recess is formed for receiving an enhanced reinforcing material formation of a generally L section lintel as claimed in any one claims I to 25.