WO1982004089A1 - Improved lintel bar - Google Patents

Abstract

A lintel bar (10) of generally L-shaped cross section is deformed along its length so as to present projecting elements (11) extending from normal planes defined by the two legs (12, 13) of the bar so that the bar (10), in combination with mortar, forms a composite beam.

Description

"IMPROVED LINTEL BAR" The present invention relates to lintel bars. BACKGROUND' ART

Lintel bars to support brickwork over windows and door openings are a major requirement of the building industry. The most popular conventional lintel bars consis of original mild steel rolled angles of various sizes. Bricklayers are presently often required to support brickwork with steel angles of strengths or dimensions that are imcompatible to the size of brickwork because bars of suitable strength and dimensional size configuration are no readily available. This causes extra work and cost. The conventional angle lintels available do not provide throughout the range, the necessary platform leg length to supply an adequate base width of support to the brickwork. The inside corner of the ordinary angle bar interferes with the edge of the brick and causes the bricklayer to cut the corners off the bricks, which is extra work; or to set the brick clear of the corner radius, thus causing further eccentric loading on the lintel. At the support ends of a lintel bar it is good practice to tuck point mortar in front of the bar to maintain appearance and or cement render around the exposed surfaces. However, in many cases with existing ordinary angle lintels this is not possible for only a thin smear of mortar can be installed and will later spall away.

As many lintel spans are wide and ordinary angles of sufficient strength for the span are heavy items, it is sometimes quite awkward to handle and lift conventional lintels into position and any bumping caused by mishandling very easily damages the prepared brickwork because at this stage the brickwork is still in a "green" uncured condition.

A frequent and serious malpractice occurs with ordinary angle lintels in that engineers' specifications will be negated because a bricklayer will position an angle the wrong way up - i.e. he will turn the shorter and weaker leg of the angle upwards and use the wider leg for the base of his brickwork; this is exactly opposite to the engineer's

requirements!

It is still a further disadvantage of known metal bars that they form a poor bond with surrounding brick work and accordingly due to the tension forces which they are required to withstand, often cause separation of the brickwork from the lintel bar.

It s an object of the present invention to overcome or substantially ameliorate the above disadvantages.

DISCLOSURE-OF- INVENTION There is disclosed herein a lintel bar of generally

L-shaped transverse cross section, said bar being deformed along its length at spaced intervals so that portions of the bar project beyond the normal plane defined by the two legs of the L-shaped cross section. BRIEF-DESCRIPTION" OF" HE'DRAWINGS

A preferred form of the present invention will now be described by way of example with reference to the aceo panying drawings, wherein: Figure 1 is a perspective view of a metal bar having deformations to enhance bonding with brickwork to be placed on the lintel bar; ^'

Figure 2 is a transverse cross section taken along the line 2-2 of the bar of Figure 1; Figure 3 is a schematic perspective view of a further lintel bar having projections to enhance bonding with the surrounding brickwork; and

Figure 4 is a schematic transverse cross section taken along the line 4-4 of Figure 3. BEST MODE OF CARRYING OUT THE INVENTION

In Figure 1 the lintel bar 10 is of a generally L-shaped transverse cross section and is deformed at longitudianlly and transversely spaced intervals so as to have projections 11. The lintel bar 10, by being of L-shaped cross section has two legs 12 and 13 which have internal faces 14 and external faces 15. The projections 11 are depicted in the present instance as being provided on the internal faces 14 with corresponding recesses on the external faces 15. However, the reverse could take place o a combination whereby the projections could be located on the external faces 15.

Turning now to Figures 3 and 4, there is schematically depicted in Figure 3 a lintel bar 20 which is also of generally L-shaped transverse cross section and which is provided with longitudinally extending ribs 21 which are joined by transversely extending ribs 22. Additionally it should be appreciated that the transverse ribs 22, while in the present instance are depicted and described as being formed on the internal faces 23, could b provided on the external faces 24.

Further, with particular reference to Figures 2 and 4, it can be seen that the lintels 10 and 20 are depicted as supporting a brick 30 with the projections 11 or ribs 21 and 22 spacing the brick 30 from the corners 31 of the lintel bars 10 and 20 such that the corner of the brick does not have to be removed to be correctly located on the lintel bars 10 or 20. Additionally, it is preferred that the effective thickness T of each leg of the lintel bars 10 or 20 be equal or less than the expected mortar thickness employed in standard brick work.

In testing of the present improved lintel bars, it has been found that the lintel forms a composite beam with the brick work it supports by establishing a sufficient bond with the mortar. This composite beam has the effect of considerably increasing the effective strength of the lintel to the extend that it approximates the strength of a standard lintel bar of almost twice its metal thickness. e.g. A standard lintel bar of 10 mm thickness only slightly exceeds the strength of a present lintel of 6 mm of thickness. The present lintel, by being provided externally of the brickwork but bonded thereto, provides a composite beam which is far superior to standard lintels due to its improved bonding characteristics with the brickwork it supports.

Claims

1. A lintel bar of generally "L-shaped" transverse cross-section, said bar being deformed along its length at spaced intervals so that portions of the bar project beyond the normal plane defined by the two legs of the bar.

2. The bar of claim 1, wherein each leg has an effective thickness of about 10 mm.

3. The bar of claim 1, wherein the deformations have an area projecting longitudinally of the bar.

4. The bar of claim 1, wherein the deformations are projections extending from the general plane of each of the legs of the bar.

5. The bar of claim 1, wherein the deformations are ribs extending longitudinally and transversely of the bar.

6. A lintel bar substantially as hereinbefore described with reference to the accompanying drawings.