AU2021203141A1 - Tensile reinforcement structures for brick walls - Google Patents

Abstract

For masonry walls made of bricks or concrete blocks, horizontal tensile reinforcement is provided by inclusion of a long metal strip buried within a layer of conventional mortar laid over a course of masonry. Retaining holes are pressed through the metal strip while unperforated metal zones along the strip edges maintain tensile strength. Edge flanges bent downwardly support the strip at a height within the mortar when first laid. The mortar penetrates the holes and locks to the strip while continuing to bond normally to the masonry on both sides of the strip.

Description

TENSILE REINFORCEMENT STRUCTURES FOR BRICK WALLS FIELD

The invention is in the general field of building construction; more particularly relating to walls made of masonry elements such as bricks or blocks, including brick veneer, that employ a form of cement such as mortar to hold the masonry elements together. Elongated members of metal are provided for the purpose of providing tensile reinforcement.

BACKGROUND OF THE INVENTION.

For a masonry structure including courses of mortar usually laid horizontally, the invention provides horizontal tensile reinforcement by inclusion of a long metal strip located within some or all layers of conventional mortar. tensile reinforcement structures for brick walls, to add a horizontal tensile strength to the mortar inserted between courses or horizontal layers of or other masonry items. Masonry items and mortar are brittle and have good compressional strength but very limited tensile strength. There are documented failures, some involving loss of life, of brick structures for which that lack of tensile strength has resulted in complete collapse. Incomplete failure results in cracking. Brick veneer is more at risk since the thickness is less.

DEFINITIONS

The term "brick" means a brick made from fired clay and in this document includes other masonry unit structures such as concrete blocks or tiles to become assembled into a structure.

"Mortar" usually comprises a mixture of Portland cement, and sand, in a 1:6 volume ratio, with water, and lime. Freshly made mortar is thick enough to support the weight of a course of masonry items placed above, until setting begins. After setting and curing over a period of perhaps 28 days according to applicable building codes, the crystalline formation made by the cement has bonded the mortar to adjoining masonry unit surfaces and inserted items.

DESCRIPTION OF RELATED ART.

Bricks are an ancient form of construction. The invention is used along a course of bricks, providing tensile reinforcement in a horizontal axis and spans a number of bricks. Like common brick ties, which are sacrificial metal components perhaps 25 mm wide that are inserted into mortar as it is laid, providing metal tabs extended outward from a surface of a brick veneer wall, that can later be fastened to studs, the invention is "sacrificial" and remains in place for the lifetime of the construction. Expansion ties to pass along from one brick to another across an expansion joint are known.

New Zealand patent 19131 to Priest (1905) teaches a longitudinal tie intended to hold together two divisions of a cavity brick wall across the cavity. Two twisted pairs of longitudinal wires of indefinite length are provided; one to become buried within the mortar between bricks on each side of a cavity. There is an intermittent bridging element of twisted wires crossing the free space between the two layers of bricks Priest's invention could be adopted for use within a single layer of bricks rather than between two layers separated by a cavity, to go part way toward solving the currently understood problems. In particular though, it would not be sufficiently stiff because of the twisted construction. It would easily be stretched by changing form around the twists when tension is applied.

The currently sold New Zealand product consists of two lengths of 4 mm diameter galvanized wire 35 mm apart, bridged at 160 mm spacing by short lengths of 2.5 mm wire welded like rungs of a ladder, to be laid within the mortar along a course.

Murfor, a company in Zwegevem, Belgium makes "type RND" or "RND/Z" masonry reinforcement in various sizes. These are comprised of two parallel wires welded together using a continuous truss wire in zigzag form. RND/Z reinforcing was used in the test lintel of Fig. 1.

PROBLEM TO BE SOLVED

New Zealand is at some risk of seismic events likely to cause brickwork to fail, while brick walls can also fail through uneven subsidence of foundation or excessive loads over an unsupported base. Earthquake damage presents particular risk to safety from falling masonry.

Because mortar once set is a hard, brittle material with substantially no tensile strength, structural walls of brick can fail if placed under tension, forming propagating cracks that may separate parts of bricks within courses, or may fracture along mortar joints. The composition of mortar is sometimes poorly controlled. It seemed useful to develop elongated metal reinforcing structures adapted for use in brickwork, especially as horizontally oriented structures passing through the mortar between courses of bricks. The structure would provide extra tensile strength.

Many brick constructions are brick veneer rather than structural brickwork. Brick veneer, with bricks typically between 55 and 125 mm thickness, is attached by brick ties embedded in the mortar to an underlying wooden or steel framework. Brick veneer commonly needs steel or reinforced concrete inserts over lintels such as around windows and doors since spans of a length desirable for function or design tend to fail. Some lintels exceed 2 metres in width.

This invention may go some way toward solving one or more of the above problems.

BRIEF SUMMARY OF THE INVENTION.

In a first broad aspect the invention provides an interlockable tensile reinforcing element for a construction including courses of masonry articles selected from a range including bricks and concrete blocks to become conventionally bonded by sequentially laying a layer of settable embedding material, herein named mortar, upon each course; wherein the interlockable tensile reinforcing element comprises an elongated strip of metal having a length, two ends, two long edges and a planar body having an upper surface and a lower surface; the planar body is modified along at least one lengthwise orientated zone by inclusion of a plurality of apertures through the planar body, thereby maintaining a tensile strength outside the zone; the interlockable tensile reinforcing element also includes at least one height-determining structure capable when in use of maintaining a height of the planar body of the strip above an underlying course of masonry articles while the strip is embedded within the mortar being laid.

Preferably each interlockable tensile reinforcing element is used in a straight configuration.

Preferably each of the plurality of apertures has a bondable periphery capable when in use of becoming engaged with the adjacent mortar and has an opening providing continuity of the mortar between the underlying course of masonry and a course of masonry subsequently laid above the mortar.

Preferably the interlockable tensile reinforcing element has a width less than the width of a top surface of a brick and when in use is buried within the mortar.

More preferably the interlockable tensile reinforcing element has a width corresponding to about 80% of the width of a top surface of a brick.

Preferably the interlockable tensile reinforcing element includes at least one lengthwise orientated, uninterrupted zone having no apertures, thereby providing a predictable longitudinal tensile strength.

Preferably, each of the plurality of apertures has a periphery capable when in use of becoming bonded to the laid mortar, while the opening of each aperture provides continuity of the mortar between the underlying course of masonry, and a course of masonry above the mortar.

o Preferably said at least one height-determining structure comprises a pair of lengthwise, elongated orientated flanges; each of which is located along each long edge of the planar body and is folded from the planar body at an angle in a first or downward direction.

Optionally the or each height-determining structure is formed on to the interlockable tensile reinforcing element as part of a separate unrolling process.

Preferably, each height- determining structure is capable, when in use, of maintaining the planar body of the interlockable tensile reinforcing element at a distance above a course to be covered in mortar.

More preferably, the planar body of the interlockable tensile reinforcing element is maintained within a middle of the thickness of the mortar.

o More preferably each flange is bent to about 45-70 degrees and typically has a projected height of about 7 mm.

In a further aspect each flange is provided with a series of apertures along its length, adapted to receive projections from selectedjoining members.

In an alternative version, the plurality of height-maintaining structures each comprises a tab protruding by a controlled distance from a lower aspect of the planar body of the interlockable tensile reinforcing element so that, during installation, the planar body is maintained above a surface to be covered in mortar by the plurality of tabs.

Preferably the invention also provides each interlockable tensile reinforcing element with apertures or sockets capable of receiving protrusions from joining members, eachjoining member providing a connection past an interruption between one interlockable tensile reinforcing element and an adjoining interlockable tensile reinforcing element.

Preferably the joining members are selected from a range including an end-to-end or in-line joint, an interruption at a corner, which may or may not be at right angles, between courses, and an interruption at a junction between courses including cross-over junctions.

Alternatively, ends of tensile reinforcing elements are provided with attachment means including bendable lugs and matching sockets or slots in order that one interlockable tensile reinforcing element can be directly joined in a line to another such element.

More preferably the interlockable tensile reinforcing element is comprised of a corrosion resistant sheet material selected from a range including sheet metal, sheet steel, stainless steel, o galvanized or other steel treated to become resistant to corrosion.

A preferred thickness of the selected sheet material will be in a range of between about 0.25 mm and 1.25 mm; thereby providing an effective tensile strength.

In a second broad aspect, a method for making each interlockable tensile reinforcing element is to form each element from a strip of metal of any convenient length by feeding it through a press provided with punches and dies.

In a first manufacturing method option each aperture through the thickness of each tensile reinforcing element is formed at a final size.

In a second option each aperture is subsequently dilated in a direction perpendicular to the length of the tensile reinforcing element.

o PREFERRED EMBODIMENT:

The description of the invention to be provided herein is given purely by way of example and is not to be taken in any way as limiting the scope or extent of the invention. Dimensions are illustrative. The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation.

In this specification, reference numerals are provided for clarification only and are not intended to restrict the scope of the invention to the particular embodiments of the components in conjunction with which the reference numerals are used.

Throughout this specification unless the text requires otherwise, the word "comprise" and variations such as "comprising" or "comprises" will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. Each document, reference, patent application or patent cited in this text is expressly incorporated herein in their entirety by reference. Reference to cited material or information cited in the text should not be understood as a concession that the material or information was part of the common general knowledge or was known in New Zealand or in any other country.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S).

Fig 1: (Prior Art) shows damage for a veneer brick lintel during a force/extension test (from Bronius Joniatis et al, Procedia Engineering 172 (2017) 465-472, Fig 7a). Title: "Experimental o Investigation of the Behaviour of Brick Lintels".

Fig 2: shows two interlockable tensile reinforcing elements laid over partial courses of bricks and up to a corner.

Fig 3: is an underneath elevation view of Example 1 of an interlockable tensile reinforcing element.

Fig 4: is a diagrammatic cross-section of an interlockable tensile reinforcing element after becoming embedded, showing the preferred longitudinal flanges and including part of a brick tie.

Fig 5: is a perspective view of an end of a interlockable tensile reinforcing element locked to a corner piece for use in a brick construction.

Fig 6: is a diagrammatic longitudinal cross-section showing the interlockable tensile reinforcing o element embedded in mortar between bricks.

Fig 7: as Figs 7a, 7b, 7c, 7d are drawings showing a sequence for conversion of part of a strip of metal into a wider strip by sideways expansion into apertures of a series of slits formed during a pressing operation.

Fig 8: is a cross-section through a typical interlockable tensile reinforcing element of the invention,

DETAILED DESCRIPTION OF THE INVENTION.

The invention is herein called a "tensile reinforcing element". For the purpose of the claims, it is called an "interlockable tensile reinforcing element", to encompass joining provisions. It is intended for use as a sacrificial component to be included within layers of mortar in for example a brick wall or a concrete block wall. It comprises an extended and substantially linear metal reinforcement structure for inclusion within a layer of mortar in between courses of masonry items. The element has a predictable tensile strength in order to compensate for the poor tensile strength of mortar and of masonry. A large force applied along its length will cause relatively little change in length, until plastic deformation or rupture occurs. It is applicable both to structural walls and to brick veneer walls, especially where lintel type structures are included.

The tensile reinforcing element is supplied in an already fully extended tape or strip form (or optionally in a coiled form for better packaging). Being made of a continuous non-kinked and non-twisted length of metal, the article is relatively stiff under tension.

Prior-Art Fig 1 illustrates the behaviour of a test lintel structure under compression and tension. o It is Fig 7(a) of Bronius Joniatis et al Procedia Engineering 172 (2017) 465-472. "Murfor" RND/Z paired reinforcing bars 4 mm diameter were included in the three lowest courses of an 85 mm thick structure, made in the laboratory according to EN 846-9 standards and allowed to cure. Fig 1 graphically illustrates a set of results while a conventional press applied a short-term static load above the top of test lintel structure. The vertical axis shows applied force in kN, tested here up to 100 kN, which is about 40% of the limit load. The horizontal axis shows a dimensional change as a ratio. The sketch at right identifies each trace by course position, counting from the lowest course of bricks. During the test, courses 7 and 8 experienced compression. But the lower courses especially 1 and 3 that were placed in tension (and included the prior-art reinforcing material) show abrupt horizontally directed extensions superimposed on o sloping lines, corresponding to detachment of the reinforcement elements from the mortar. All traces but 7 and 8 (shown in the original in different colours and each corresponding to one course of bricks where 1 is the lowest course, and most exposed to tension) include a different amount of slippage. Such detachment events are not desired.

Example 1.

(See "Manufacture" below. ) A number of apertures 108, 109, 110 through the planar body 111 of the article are provided in order that mortar can penetrate the body as the course is laid, in order to bond the bricks above and below on each side to each other in the usual way, while forming contacts between the mortar and the article mainly at edges of formed apertures. Tensile forces are shared or distributed between the tensile reinforcing element and the adjacent mortar at the borders of each aperture, through which mortar has flowed before setting and remained in place. Fig 2 is a perspective diagram showing portions of two structures 100, 100 according to the invention, placed over parts of two courses of bricks 202, 202 leading to a corner 203 and also shows a first brick 201 of a later course. Fig 5 shows details of a corner connector (hidden in Fig 2) used to join the two structures.

Fig 3 shows a short section of a tensile reinforcing element 100 from an underneath side. The Applicant's structures exists as repeats of the profiles shown in Fig 3, including apertures 108, 109 and 110 made through the planar body that is comprised of a shaped metal strip.

Since the intention is to bond the tensile reinforcing element, which is relatively stiff and resistant to deformation by tension into a tension-weak matrix (the mortar) thereby creating an inter-course bond along a course of bricks and adding a tensile strength, the metal is preferably not expected to exhibit ductile or plastic flow under reasonably expected conditions of use. Materials testing will better define permissible thicknesses. It is desirable that the tensile reinforcing element is laid out along a straight line when in use, so that any tension that may be applied along its length tends to stretch the metal directly.

Zones of the tensile reinforcing element are shown in a cross-section in Fig. 8, which may be compared with the version shown in Fig. 7d (A-A') or the version shown in Fig. 3. Two flanges, 101 and 105 are along each side of a central planar body 111 which has a generally perforated central portion 112 and two unperforated sides 102a, 104a which merge with the flanges 101, 105 at folds. When in use, edges of the perforations 108, 109, 110 of the central body form a o multitude of contacts, or bonds, with the mortar that had been applied on to each side of the tensile reinforcing element so that it becomes entirely buried within mortar. Forces that may be applied to those contacts at perforation edges in particular are distributed along the two unperforated sides of the tensile reinforcing element when it is placed under tension. The two flanges serve to maintain a spacing between the planar body of the tensile reinforcing element and a surface of a masonry item 710 on which the tensile reinforcing element has been located. That allows a bond to be formed between the masonry below the mortar and the mortar as is the usual practice in construction of brickwork, while the apertures allow the mortar to reach the underside of the course above.

102a and 104a indicate the lines of two folds for forming a first edge flange 101 and a second edge flange 105 respectively along the two sides of the tensile reinforcing element. Each flange provides a continuous band of metal along each long edge, for receiving tension. Periodic nicks 102 may be provided in order to allow applied mortar to flow across the flange. 103 and 106 indicate two of a series of holes made through each flange that are usable during installation to serve as sockets for interlocking connection with other structures. 107 and 111 indicate the planar part of the tensile reinforcing element. The holes are best shown in Fig 5.

Flanges 101 and 105 are shown as forming obtuse angles, typically about 45-75 degrees with the underside of the planar body, so that a plurality of elements can be stacked, or rolled for shipping. See also Fig 8 for a cross-section. The projected height of each downwardly directed (when in use) flange is about 7 mm, to provide a space under the article and above a masonry o item below (712) to receive mortar. The flanges prevent the article from falling to the bottom of the layer of mortar so that the mortar will not make a good bond to the masonry below and the construction would be more likely to fail.

One equivalent of the flanges would be to provide extended tabs along the length of the tensile reinforcing element, like feet. They may be bent away from the plane of the article at the time of manufacture and would serve, when in use, to keep the main part of the tensile reinforcing element up and off the underlying masonry articles.

Actual dimensions of the tensile reinforcing element, namely the width, the height of the planar body above a surface when supported by flanges, and the useful length may be varied according to masonry unit dimensions since many sizes and proportions of brick or concrete block, for o example, can be obtained. The element may have a width corresponding to about 75% of the width of a top or bottom surface of a brick. Some building codes require that at least 20 mm of mortar exists between any part of an embedded metal article and the exterior. For example, an element has a planar body width of 35 mm and is good for 75 mm wide veneer bricks.

The tensile reinforcing element may be supplied after manufacture in a rolled form or as straight lengths such as multiples of 2.4 metres, for convenience during shipping and handling. The element may run over the span of a lintel plus an adequate safety overlap, or over the length of an entire course of bricks. Each length has end-linking attachments such as lugs and matching sockets (See Figs 4 and 5 for details) in order that one length can be joined to another. The configuration of the flange allows the installer to shape the article with tinsnips and connect it to another article or to a corner piece.

Manufacture

In a preferred manufacturing method, a stock of sheet metal strip is obtained as for example a one tonne coil that is fed through a press that deforms and perforates the article, creating tensile reinforcing elements of unlimited length. Typically a series of stations are included within a press and the strip is fed from one to the next in an incremental manner. The side flanges may be bent away from the planar body either in the press or by a subsequent rolling process as is known in the relevant arts. The thickness of the selected sheet material will be optimized in relation to possible deformation by applied forces and in accordance with results of industry evaluation tests to be carried out.

o Expanded holes formed from slits, as in Example 2 below, may be created with additional steps in the same type of stage-by-stage pressing operation.

Materials.

The tensile reinforcing element is intended to be stiff under tension. Preferably, when it is placed under tension within limits, its elongation is not large enough to distort the attached set mortar, and also, it will not become deformed by elongation past the elastic limit. It is noted that steel products currently sold in New Zealand for this purpose are two parallel 4 mm diameter rods with a total cross-sectional area of 25.1 mm 2 . An Example 1 (0.6 mm thick and 40 mm wide) tensile reinforcing element has a combined cross-section of 12.6 mm2 outside the apertured zone.

o The tensile reinforcing element is preferably corrosion-resistant at least over the duration of life of the structure having regard to building codes and the possibility of a salty, marine environment. An element not made of an inherently corrosion-resistant material in bulk such as one of the stainless steel alloys or an aluminium alloy is preferably treated after manufacture with an anti-corrosion coating such as galvanizing, or a passivating surface having a sufficient lifetime. An epoxy coating might be applied during construction on to site-caused cuts.

The thickness of the selected sheet material will be optimized in relation to possible deformation by applied forces and in accordance with building codes and requirements established by industry evaluation tests. Steel strip may be of between about 0.25 mm and 1.25 mm thickness.

Apertures. (Example 1)

The Example 1 interlockable tensile reinforcing element is provided with a repeated series of apertures such as 108, 109, 110 along its length, connecting the upper and lower sides of the planar body. Each aperture is made conventionally using a punch and a matching die and the holes are not subsequently deformed. Preferably the aperture outlines are designed in order to best spread compressive forces within the body of mortar adjacent to hole edges, where mortar applied during the laying process has been placed, and subsequently hardened. The apertures may be designed to optimize second uses of scrap metal.

A bricklayer who normally applies mortar along a course in one pass may place the tensile reinforcing element on the upward-facing brick surface before covering it with mortar, jiggling the mortar with the trowel or agitating an exposed end of the article to cause the mortar to slump, 1o pass through the holes and make effective contact with the upward-facing brick surface below. Or, the bricklayer would place the tensile reinforcing element upon a first thinner layer of mortar, tap it down, then cover it with a second thinner layer. At this time, the flanges of the tensile reinforcing element will maintain a thickness of mortar beneath. Fig 6 is a longitudinal section through mortar 403 surrounding a tensile reinforcing element 107, with hole edges as at 109. It will be apparent that the element is completely embedded within the mortar. Bricks are indicated at 401 and 402. Complete immersion of the article in mortar is shown in Fig 6, surrounding aperture 109. In this Figure, the hole edges are shown with lips 601 and 601a, for distributing compressive forces into the adjacent mortar. Fig 6 shows a lipped aperture 601, surrounded at least on the long axis by lips 602 and 603. Lips 601 may be formed within the o press for example by providing the punches with shoulders and driving them through the material past the shoulders. Such lips would tend to reduce the abrupt failure modes shown in the prior-art Fig 1. Deep lips may replace the edge flanges, resembling the tabs mentioned in this section.

When cavity bricks or concrete blocks are used to create a masonry wall, vertical steel reinforcing bars may be used; passed through aligned cavities of many courses of brick. The apertures in the planar section may be pre-aligned to also allow passage by steel bars, or the bricklayer can cut between apertures with tinsnips to allow the steel bars to pass.

While the mortar sets, after being covered by the course above, it will become keyed to the edges of each aperture 108, 109, 110 while bricks above and below become bonded. Mortar that passes through apertures made in the tensile reinforcing element will bond to the aperture edges. There may be some bonding to the plane surface. As a result, the tensile reinforcing element provides permanent tensile reinforcement for the mortar of a wall during a lifetime of the wall. Even after excessive loading has occurred the tensile reinforcing element may assist in holding the bricks together without total failure of the wall.

Expanded Apertures. (Example 2) Fig 7 as Figs 7a, 7b, 7c, and 7d, shows steps of a sequential process for conversion of a metal strip 700, an unaltered portion of which is shown in face view (Fig 7a) into a tensile reinforcing element, by forced sideways expansion of a series of slits (701) created during a pressing operation. Fig 7b shows the first step; a number of punched slits 701 pressed through the blank strip. Preferably, each one has a dominant axis along the length of the strip, and preferably each slit terminates in a part-circular profile 702 at each end, rather than ending in sharp comers, in order to minimise potential crack formation. Fig 7c shows in a diagrammatic form the effect of forcing the slits into ovals by pressing a tapered, partially rounded shape into each slit. This operation is intended to be performed cold although it could be done on heated metal. A sub-sequence forms a central set of holes first. Then the tapered shape forming each of them is left in place while the more peripheral holes are dilated in the same way, after which the shapes are withdrawn. As a result, as shown in Fig 7c, the edges 704 of the strip become extended sideways and may have a wavy edge since the expansion operation is applied in a discontinuous way. Fig 7d illustrates a portion of thefinished tensile reinforcing element. It has become wider than the original strip as a result of deliberate sideways expansion. Two folded flanges 101, 105 have been formed along the tensile reinforcing element after the edges 706 have been optionally trimmed into straight edges - because the wavy edges allow mortar to flow sideways under the flanges. The folding created flanges 708 and 709. A series of holes for use with joining clips (see below) may be added before folding. Any of the slitted holes (such as 707) could be made as a significantly larger aperture instead, in a version mixing Examples 1 and 2. The proportion of hole 707 to metal 700, and hole size may be changed in order to allow for better flow of mortar during laying. As for Example 1, this version of the invention also has holes 103 for connecting to interlocking joiners as previously described in this section. Finally, Fig 8 shows a cross-section 710 through part of the tensile reinforcing element of Fig 7d along the line A-A' to show the supporting flanges 708 and 709. Tensile reinforcing elements of Example 1 have a similar cross-section.

Corners.

The invention also provides a range of customized joiners; that will engage with an end of the tensile reinforcing element of either Example 1 or of Example 2, at straight or end-to-end joints, right-angled corner joints, "T" intersection corners, and "+" intersection joint. Angles other than 90 degrees can be provided at corners. It is desirable that any joint can transmit tensile forces without stretching.

An example corner element is shown in Fig 5 as 501. Note that the corner element has protruding lugs 502 at both ends which can be engaged with adjacent holes 103 through the flanges of the terminated elements, as shown. Structures can be cut to a suitable length with appropriate tools near a corner. The installer may add an anti-corrosion coating to bare surfaces.

Comer elements preferably also include apertures through the planar body for admitting mortar as shown at 503. Elements may be made using computer-controlled laser cutting or an equivalent process in case custom designs are required.

Further research is expected to clarify the amount of extension of the tensile reinforcing element that can be tolerated before the mortar becomes degraded by local pressures about the apertures, and to establish how tightly coupled the tensile reinforcing element should be, on an aperture-by aperture basis, with the mortar. A structure receiving damage may survive better if tension is o allowed to be distributed over a short length.

RESULTS and ADVANTAGES

For a relatively low cost, a brick wall can when under construction be provided with an effective linear reinforcement compatible with current construction methods. Prior-art Fig 1 shows an effect of insufficient bonding to a reinforcing element, overcome by this invention.

The invention will reduce the amount of catastrophic failure as may happen during an earthquake, or during slow failure during subsidence of foundations, or distortion and crack formation caused by changing loads within structures supported by the bricks.

The invention will allow elongated-width lintels to be constructed using veneer-thickness bricks as well as lintels made with standard width bricks.

o It is possible to include conventional brick ties to adjacent structures, and the tensile reinforcing element in the same mortar, since neither are too thick.

As opposed to existing tensile reinforcement devices, this invention has no welded parts or other joins within the elongated structures, and the aperture edges allow more precisely controlled engagement with the mortar, distributed along a course of bricks or other masonry items.

Finally it will be understood that the scope of this invention as described and/or illustrated herein is not limited to the specified embodiments. Those of skill will appreciate that various modifications, additions, known equivalents, and substitutions are possible without departing from the scope and spirit of the invention as set forth in the following claims.

Claims (1)

1. I/WE CLAIM Claim 1: An interlockable tensile reinforcing element for a structure including courses of masonry articles including bricks and concrete blocks to become bonded by mortar; wherein the interlockable tensile reinforcing element comprises an elongated strip of metal having a length, two ends, two long edges and a planar body having an upper surface and a lower surface; the planar body is modified along at least one lengthwise orientated zone by inclusion of a plurality of apertures through the planar body, thereby maintaining a tensile strength outside the zone; the interlockable tensile reinforcing element also includes at least one height-determining structure capable when in use of maintaining a height of the planar body of the strip above an underlying course of masonry articles while the strip is embedded within the mortar being laid.

   ' Claim 2: The interlockable tensile reinforcing element as claimed in claim 1, wherein each of the plurality of apertures has a bondable periphery capable when in use of becoming engaged with the adjacent mortar and has an opening providing continuity of the mortar between the underlying course of masonry and a course of masonry subsequently laid above the mortar.

   Claim 3: The interlockable tensile reinforcing element t as claimed in claim 1, wherein said at least one height-determining structure comprises a pair of lengthwise orientated flanges; each of which is located along each long edge of the planar body and is folded from the planar body at an angle in a first or downward direction.

   Claim 4: The interlockable tensile reinforcing element as claimed in claim 2, wherein said at least one height-determining structure comprises a plurality of tabs, each bent away from the planar body in order to protrude in the first direction by the height.

   Claim 5: The interlockable tensile reinforcing element as claimed in claim 3, wherein each element is provided with a series of sockets each adapted to receive and hold a protrusion from a joining member, thereby becoming interlocked with at least one other interlockable tensile reinforcing element.

   Claim 6: The interlockable tensile reinforcing element as claimed in claim 5, wherein the at least one joining member is selected from a range including an end-to-end joint, an interruption at a corner between courses; said corner including angles of 90 degrees and angles of other than 90 degrees, and an interruption at a junction between said interlockable tensile reinforcing elements.

   o Claim 7: A method for making the interlockable tensile reinforcing element as claimed in claim 1, wherein each of the apertures and bends are formed within a metal strip by a press.

   Claim 8: A method for making the interlockable tensile reinforcing element as claimed in claim 7, wherein each of the apertures are first formed by a punch within a press and then are dilated by a sideways force that is applied to the sides of each aperture within the press.