AU2004201567B2

AU2004201567B2 - A flexible joint

Info

Publication number: AU2004201567B2
Application number: AU2004201567A
Authority: AU
Inventors: Joseph P Borg
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-04-16
Filing date: 2004-04-13
Publication date: 2007-11-22
Anticipated expiration: 2024-04-13
Also published as: AU2004201567A1

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): JOSEPH P BORG Invention Title: A FLEXIBLE JOINT The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 A FLEXIBLE JOINT The Field of the Invention The present invention relates generally to a flexible joint for use in the construction industry. More particularly, the present invention relates to a flexible joint system which can be used as an expansion joint, control joint and/or articulation joint in a structure.

The flexible joint conceals gaps in a structure or between structures and is able to deform in accordance with the normal movements of the structure(s).

Background to the Invention Structures such as buildings, towers, walls, platforms or the like have a degree of natural movement during the structure's lifetime. Movement can be the result of moisture expansion or drying contraction of the material of construction, variations after construction material are loaded or unloaded, foundation or footing movements, or a combination thereof. The degree of movement can be exaggerated by the use of different materials and their different responses to changing loads, temperatures and moisture contents. These movements can also be affected by seasonal variation and diurnal thermal changes in the environment.

Natural movement is particularly prevalent in structures constructed of brittle material such as brick and concrete. Concrete, and cement products shrink over time, whereas clay bricks slowly expand. Consequently, it is standard practice to include construction gaps into the structure at predetermined locations in order to accommodate normal movement of the structure. Typically, the construction gap is at least 10 mm wide.

H,\jolxik\keep\Speci\P52588 Plexible joint complete.doc 13/04/04 3 For the purposes of this specification, the term "construction gap" is intended to include expansion gaps, control gaps and articulation gaps. An expansion gap is a gap placed in a structure, such as a brick structure, to accommodate the expansion of the material the structure is made of over time. The expansion gap is closed as the material expands. A control gap is a gap placed in a structure to accommodate the differential movement of the structure, changes due to thermal variations or settlement of the structure's foundation or slab. An articulation gap acts as an expansion and control gap.

Traditionally, construction gaps are filled with a preformed foam filler material. However, the foam filling system does not optimally fill the construction gap in the structure. Typically, the foam is not fixedly secured or even substantially compressed within the construction gap. The foam is therefore able to move within the construction gap. Expansion of the gap can result in spaces between the foam and sides of the gap.

Such spaces allow moisture, insects and dirt to penetrate into the structure's interior.

The use of the foam in such construction gaps is also considered by some to be aesthetically unpleasant. In these circumstances a concealing board can also be placed in front of the foam, so as to conceal the foam. This board is typically constructed of a flexible material such as mastic or silicon. Consequently, movement of the structure can damage the concealing board. Again, the presence of a damaged concealing board can be considered to be aesthetically unpleasant.

Furthermore, it is not possible to judge the severity of the movement of the structure from the appearance of the existing methods. In each case, the H,\jolzik\keep\Speci\P52588 Flexible joint complete.doc 13/04/04 -4presence of the spaces or the damage to the concealing board only gives an indication that the structure has moved. The widening of a construction gap often leads to unnecessary reporting of what is essentially normal movement to a builder or structural engineer.

It would therefore be advantageous to have a concealing device that overcomes at least some of the disadvantages of the prior art construction gap filling techniques.

SUMMARY OF THE INVENTION According to one aspect of the present invention there is provided a flexible joint system for placement into a construction gap defined between two structural elements, the flexible joint system comprising, a flexible element configured to extend into the construction gap, engage each of the structural elements and deform in response to movement of the structural elements relative to one another, and a strap adapted to extend between and be attachable to the two structural elements, the strap having a deformation element which allows the strap to deform, and the strap being interengageable with the flexible element.

Preferably the flexible joint system comprises a cover element for concealing the construction gap, the cover element being attachable to the flexible element.

During natural movement of structural elements of a structure, the flexible joint system may conceal the construction gap using the cover element and may deform within the construction gap using the flexible element. The structural elements may be part of a single structure or may belong to separate abutting structures.

The cover element is preferably sized to conceal the construction gap for a predetermined amount of relative movement of the structural elements. Preferably, the predetermined amount of relative movement of the structural elements substantially corresponds to the onset of relative movement between the structural elements which is detrimental to a structure including the structural elements. In practice, this may be achieved by 2007-11-09,H:\Specifications\borg.specamendwpd,4 constructing a flexible element having a cover element which extends a predetermined distance past the either side of the two structural elements of the construction gap corresponding to the predetermined amount of relative movement. The predetermined distance may depend on the nature of the structure and structural members, the material of construction, etc. The predetermined distance may be between 1 and Preferably, the cover element is also detachable from the rest of the flexible member.

This may allow the flexible members to be placed within the construction gap independently of the cover, allow the cover member to be detached at any time after placement so as to for example inspect the construction gap or flexible member, and/or allow the cover element to be replaced if for example the cover element is damaged.

Preferably, such a detachable cover element is secured to the flexible joint using corresponding attachment means that are independently fixed to the cover element and flexible element. Preferably, the attachment means are hook shaped connectors. The hook shaped connectors may be attached to the cover element and flexible element in an orientation which allows the hook shaped projection in the cover element to securely fasten within the corresponding hook shaped projection attached to the flexible element.

Preferably, the flexible members can flex and/or bend about the point at which the flexible member are attached to the cover member.

The cover element may further comprise at least one angled section, configured to conceal a construction gap between two structural members having outer surfaces located at an angle to one another. This embodiment of the flexible joint therefore allows the flexible joint to be configured to conceal a construction gap between structural elements which have outer surfaces that are positioned at an angle to one another. The outer surfaces may for example be the surfaces of two walls positioned at an angle to one each other, for instance in a corner.

Preferably, the flexible element comprises two spaced apart members which abut respective structural elements and are joined by a biasing means. In a preferred 2007-11-09,H:\Specifications\borg.specamend.wpd,5 -6embodiment of the present invention, the biasing means is a flexible V-shaped member.

The flexible element may also include engagement portions which engage the two structural elements of the construction gap. The engagement portions may comprise any form of projections, ribbing, fingers or bristles which help secure the flexible element between the two structural elements.

Preferably, the flexible joint can further include at least one fastening means, which can be used to fasten the flexible joint to a corresponding securing means located in or on at least one of the two structural elements. In a preferred embodiment, the fastening means is located on the flexible element. One preferred application of the fastening means is used to secure the flexible element to a window or door frame, one side of the window or door frame being the structural element having the connector.

In a preferred embodiment of the present invention, the flexible joint can be used as a warning system for excessive movements of the structure or structures. In this respect, a flexible joint system according to the invention may be located in a construction gap defined between two structural elements in the structure. The cover element of the flexible joint may be constructed of a size which conceals the construction gap until the onset of relative movement between the structural elements which is detrimental to the structure. A warning of excessive movements of the structure may be indicated by the cover element having moved to a point at which the construction gap is exposed.

In one embodiment, the cover element is constructed to predetermined dimensions which expose the construction gap once the structural elements have undergone a predetermined amount of movement relative to one another. Therefore, the cover element may be sized so that it is moved from a normal position to a warning position after significant movement of the structural elements occurs. Preferably, the warning projection is indicated by the cover element having moved to a point at which the construction gap is exposed. Exposure of the construction gap may give a visual indication that further investigation should be undertaken.

2007-11 -09,H:\Specifications\borg.specamend.wpd,6 -7- According to another aspect of the present invention there is provided a flexible joint system for placement into a construction gap defined between two structural elements, the flexiblejoint system comprising a flexiblejoint which comprises a cover element for concealing the construction gap, and a flexible element attached to the cover element, the flexible element configured to extend into the construction gap, engage each of the structural elements and deform in response to movement of the structural elements relative to one another, a strap which extends between and is attached to the two structural elements, the strap having a deformation element which allows the strap to deform, and a connecting means which secures the flexible joint to a corresponding attachment means of the strap.

Preferably, the strap comprises a flat planar member incorporating a deformation section.

Preferably, the deformation section is a biasing means. Preferably, the biasing means is a V-shaped projection. Preferably, the strap is constructed of a flexible material.

Preferably, the strap is also used as a wall tie, particularly a brick wall tie used in construction gaps.

Preferably, the deformation section is of a size and configuration that allows the strap to undergo a predetermined amount of compression or expansion during movement of the structure.

The flexible joint system may also be used as a warning system for excessive movements of the structure or structures. In this respect, a warning system for excessive movements of a structure may be provided comprising a flexiblejoint system according to the present invention located in a construction gap defined between two structural elements in the structure. The strap may have a predetermined amount of deformation substantially corresponding to the onset of relative movement between the structural elements which is detrimental to the structure. A warning of excessive movements of the structure may be indicated by damage to the strap.

The present invention may provide a warning system for excessive movements of a 2007-11-09,H:\Specifications\borg.specamend.wpd7 -8structure in two respects: firstly, the cover element may be constructed to a size which exposes the construction gap once the structural elements have undergone a predetermined amount of movement relative to one another, a warning being indicated when the construction gap is exposed; and/or secondly, the strap may be constructed having a predetermined amount of deformation which substantially corresponds to the onset of relative movement between the structural elements which is detrimental to the structure, a warning being indicated when the strap is damaged.

According to another aspect of the invention, there is provided a strap for a flexible joint system for placement into a construction gap defined between two structural elements, the flexible joint system comprising a flexible element configured to extend into the construction gap, engage each of the structural elements and deform in response to movement of the structural elements relative to one another, wherein the strap is adapted to extend between and be attachable to the two structural elements, the strap having a deformation element which allows the strap to deform, and the strap being interengageable with the flexible element.

For the purposes of this specification, the term "flexible joint" is intended to include expansionjoints, controljoints and articulationjoints. An expansionjoint is ajoint used in an expansion gap. A control joint is ajoint used in a control gap. An articulationjoint is a joint used in an articulation gap. Accordingly, the flexible joint of the present invention may be used as an expansionjoint, control joint and/or articulation joint.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described with reference to the figures of the accompanying drawings, which illustrate a particular preferred embodiment thereof, wherein: 2007-11-09,H:\Specifications\borg.specamend.wpd,8 -9- Figures 1 a and 1 b are section plan views of two embodiments of a flexible joint of the present invention, showing the configuration of the cover element and flexible element of each embodiment.

Figure 2a is a sectional plan view of the flexible joint of Figure la placed within a construction gap.

Figure 2b is an elevational view of Figure 2a illustrating the flexible joint placed within a construction gap. The flexible joint is illustrated as a cutaway view so as to highlight the location of the construction gap.

Figure 3 is a sectional plan view of another embodiment of the flexible joint, showing the configuration of the cover element and flexible element.

Figure 4 is a sectional plan of another embodiment of the flexible joint intended to be used as window or door joint, showing the configuration of the cover element, flexible element and a fastening means.

Figure 5a is a sectional plan view of one embodiment of the flexible joint system, showing the arrangement of the flexible joint element of Figure 3 secured to a strap.

Figure 5b is an elevational view of the flexible joint system of Figure 5A located within a construction gap. The flexible joint is illustrated as a cutaway view so as to highlight the location of the construction gap.

Figure 6 is a plan view of the strap of Figure 5a, showing the configuration of the securing means and the deformation means.

Figure 7 is a main elevation view of the strap of Figure 6, showing the configuration of the deformation means.

2007-11 -09,H:\Specifications\borg. specamend.wpd,9 Figure 8 is a sectional plan view of a cornerjoint embodiment of the flexible joint system within a construction gap, showing the arrangement of the flexible joint element when secured to a strap, and the configuration of the cover element.

Figure 9 is a sectional plan view of an embodiment of the flexible joint having a secondary attachment means in between a window or door fitting and a wall structure, showing the arrangement of the flexible joint element secured against the wall and the secondary attachment means secured within a corresponding connecting means attached to the window or door fitting.

Figure 10 is a sectional plan view of an embodiment of the flexible joint system showing the configuration of the cover element 1 a.

Figure 11 is a sectional plan view of an embodiment of the flexible joint system showing the configuration of the corner cover element.

Figure 12 is a sectional plan view of one embodiment of the flexible joint system showing the arrangement of the flexible joint element and the configuration of the corner cover strap.

Figure 13 is a sectional plan view of a corner joint embodiment of the flexible joint system within a construction gap, showing the arrangement of the flexible joint element when secured to a strap and the configuration of the cover strap 1 a.

Figures 14a and 14b are a sectional plan view of a corner joint of the embodiment of a flexiblejoint of the present invention showing the configuration of the cover element and flexible element.

Figure 15 is a sectional plan view of the flexible joint of Figure 14a placed within a construction gap.

2007-11 -09,H:\Specifictions\borgspecaend. -11 DESCRIPTION OF THE PREFERRED EMBODIMENT The preferred embodiment of the present invention provides a flexible joint system for use in the construction industry. The flexible joint system may be used in place of current methods to conceal a construction gap between two structural elements of a single structure or separate abutting structures. For example, the structural elements may be: two walls of a structure as shown in Figure the walls of two different structures; in a corner between two walls arranged at an angle to each other as illustrated in Figure 8; a wall and a window fitting as shown in Figure 9; a door frame and a wall; or a wooden frame and a window fitting.

In each of these examples, the construction gap is typically elongate and substantially vertical. It is to be understood that the dimensions of the flexible joint in each of these cases will be adapted to fit into and conceal these gaps. Furthermore, the flexible joint including the cover element and flexible members, is typically constructed as an elongate member having substantially the same length as the height of the gap into which the flexible element is placed. As structural elements such as walls, etc. can be more than 2 to 3 metres high, the flexiblejoint is typically an elongate member, formed for example, as one or more extrusions and cut to length.

For example, Figures 1 and 2 illustrate one embodiment of the flexible joint of the present invention which comprises a substantially planar cover element 1 fixably attached to a two spaced apart rectangular members 5. The two rectangular members 5 function as the flexible element 4. In order to fit into a particular construction gap 26 as a single piece, the cover element 1 and rectangular members 5 are typically constructed to substantially the same length as the height of the gap 26 into which the flexible element is placed. This results in each of the cover element 1 and rectangular members 5 being 2007-11-09,H:\Specifications\borg.specamendwpd, I 12elongate planar members.

Accordingly, the two rectangular members 5 are typically two elongate planar rectangular members constructed of a flexible material such as plastic. The two rectangular members 5 are fixably attached to the cover element 1. The two rectangular members 5 may be attached perpendicular to the cover element 1 (as shown in Figure 1 or may be laterally attached at an angle 9 (as shown in Figure lb). Angle 9 is typically between 60 and 900 to increase the capacity of the flexible joint to engage the structural elements.

When placed in a construction gap 26, as illustrated in Figures 2a and 2b, the rectangular members 5 engage the sides 21 of the construction gap 26. During movement of the sides 21 of the construction gap 26, the rectangular members 5 can flex together or flex apart to accommodate this movement. As each rectangular member 5 is securely affixed to the cover member 1, each rectangular planar member 5 flexes about the point at which each rectangular planar member 5 is attached to the cover member 1.

The two rectangular members 5 include engagement portions in the form of spaced apart ribs 7 which extend the length of the rectangular members 5 and help the members engage the two structural elements 24 of the construction gap 26. The ribs 7 extend at an angle 7A laterally away from the exterior of the two rectangular members Preferably, the ribs 7 are angled toward the cover member 1 so as to prevent the flexible member 4 from sliding out of the construction gap 26. The angle 7A is usually between to 45'. Accordingly, when the flexible joint 17 is inserted into a construction gap 26 (as illustrated in Figure the ribs 7 engage inside surfaces 21 of each of the structural members 24 thereby aiding in holding the flexible joint 17 within the construction gap 26.

The cover element 1 is a substantially elongate rectangular planar sheet made of a flexible material such as plastic. This results in the cover element 1 being a long thin rectangular member having a length substantially the same length as the height of the gap 26 into which the flexible element 17 is placed. The width of the cover element 1 is sufficient 2007-11-09,H:\Specifications\borg.specamend.wpd,12 -13to conceal the construction gap 26, as shown in Figure 2b.

As illustrated in Figure 2a and 2b, the cover element 1 can include two overlap sections 1A which extend a predetermined distance 15 past either the exterior sides of the elongate rectangular sheets 5. The predetermined distance 15 corresponds to the allowable movement of the cover element 1 can have during normal relative movement of the two structural elements 21. This normal position occurs when the cover element 1 conceals the gap 26.

The two overlap sections 1A allows the flexible joint 17 to be used as a warning system of any detrimental movement has occurred to the structure of which the structural elements 24 comprise. In this regard, the cover element 1, in particular the two overlap sections 1A, are sized so that the cover element 1 is moved from the normal position to a warning position after significant movement of the structure(s) occurs. The warning position is indicated by the cover element 1 having moved to a point at which at least one of the overlap sections 1A no longer conceals the gap 26. Exposure of the gap 26 gives a visual indication that further investigation should be undertaken. For example, if movement caused by foundation or footing disturbances significantly move at least one of the structural elements, this movement could also move the cover element 1 away from the normal position.

The warning position is dependent on the predetermined distance 15 associated with the overlap sections 1A. If the movement is greater than a predetermined distance 15, the construction gap 26 will be exposed. Persons skilled in the art would appreciate that the predetermined amount of relative movement of the structural elements 24 will depend on the allowable normal movement of a structure or structures that the two structural elements 24 are part of. Accordingly, the size of the cover element 1 will depend on the initial size of the construction gap 26, the structural requirements of the structure 24 and/or the allowable increase in construction gap size 26A. Typically, the predetermined distance 15 is between 1 and 10mm. For example, in brick structures the predetermined distance 15 is typically 4 to 6mm.

2007-11 -09,H:\Specifications\borg.specamed.wpd,13 -14- Another embodiment of the present invention is illustrated in Figure 3. The flexiblejoint comprises a detachable cover element 2 attached to a flexible element 4 using complementary and interlocking attachment hooks 18 and 19. The illustrated attachment hooks comprise complementary hook shaped ribs 18, 19 extending the length of the cover element 2 and the flexible element 4 respectively. Each hook-like rib 18, 19 are independently fixed to the cover element 2 and flexible element 4.

2007-1 1-09,H:\Specifications\borg.specamendwpd,14 15 The cover element 1 is a long thin rectangular member having a length substantially the same length as the height of the gap 26 into which the flexible element is placed. However, as shown in figure 3, the cross-section of the cover element 2 comprises a slight curve.

Again, the width of the cover element 1 is sufficient to conceal the construction gap 26, as shown in figure 2b. In this respect, the rectangular cover element 2 includes two overlap sections 2A which extend a predetermined distance 16 past either the exterior sides 6A of the elongate rectangular sheets 6. The cover element 2 can therefore be sized so that it is moved from a normal position which conceals natural movement the two structural elements 21 to a warning position once significant and/or detrimental movement of the structure(s) occurs. The warning position being indicated by the cover element 2 moving to a point at which at least one of the overlap sections 2A is not concealing the gap 26A. Exposure of the gap 26A gives a visual indication that further investigation should be undertaken.

The predetermined distance 16 corresponds to the allowable movement, usually sideways movement, of the cover element 2 during normal relative movement of the two structural elements 21. The predetermined distance 16 is dependent on the initial size of the construction gap 26, the structural requirements of the structure 24 and/or the allowable increase in construction gap size 26A. For example, in brick structures the predetermined distance is typically 4 to 6mm.

The flexible element 4 comprises two elongate rectangular members 6, inter-connected by a biasing means in the form of a V-shaped flexible member 8. Like the cover element, the rectangular members 6 and a V-shaped flexible member 8 are constructed to substantially the same length ffi\jOlzik\keep\Speci\P52588 Flexible joint COniplete .doc 13/04/04 16 as the height of the gap 26 into which the flexible element is placed.

The V-shaped flexible member 8 extends to a point 7 within the interior of the flexible element 4. The Vshaped member 8 can deform when compression or expansion forces are applied to the two elongate rectangular sheets 6. Both the two rectangular members 6 and V-shaped flexible member 8 are constructed of a flexible material such as plastic. The two rectangular members 6 engage the two structural elements 21 of the construction gap 26.

These rectangular members 6 may also include engagement portions such as ribs, projections or the like, which enhance engagement with the structural elements 24 of the construction gap 26.

The flexible element 4 also includes two hook shaped ribs 10 extending the length of the flexible element 4. The hook shaped ribs 10 affixed to the flexible element 4 about the area 9A where the elongate rectangular members 6 join with the V-shaped flexible member 8. The hook shaped ribs 10 function as connecting means for this embodiment of the flexible joint. The two hook shaped ribs are orientated so that the ribs 1OA and lOB face in opposite directions away from the centre of the flexible joint 7. The hook shaped ribs 10 can be used to attach the flexible joint to complementary recesses 33 in a strap 22, as illustrated in figures 5A and SB.

When placed in a construction gap, as illustrated in figures 5A and 5B, the rectangular members 6 engage the sides 21 of the construction gap 26. During movement of the sides 21 of the construction gap 26, the elongate rectangular members 6 can flex together or flex apart to accommodate this movement. Each rectangular members 6 is held substantially static flexes at the point at which each rectangular members 6 is attached to the cover member 1.

8-\Jolik\keeP\SPeci\F52588 Flexible joint Cocrplete.c10 13/04/04 17 Each rectangular members 6 therefore flexes about the point at which each rectangular members 6 is attached to the cover member 1. The V-shaped member 8 similarly deforms when compression or expansion forces are applied to the two elongate rectangular sheets 6A.

The flexible joint can also be constructed to conceal construction gaps in a corner between two walls 24,25 arranged at an angle 27 to each other (as illustrated in figure or between a wall 40 and a window fitting 42 (as shown in figure Figure 4 illustrates a corner joint embodiment of the flexible joint that is suited to these corner type applications. This embodiment of the flexible joint differs to the embodiment illustrated in figure 4 with respect to the inclusion of a corner section 3 to the cover element 2. The corner section 3 protrudes at an angle 27A away from the outer face cover element 2, so as to allow the cover section to extend around the outer surfaces of each wall comprising the corner 25. Preferably, the corner section 3 of the cover element 2 projects at substantially the same angle 27A as the angle between the outer surfaces of the structural elements of the corner gap. In the illustrated embodiment the angle 27A is degrees. Furthermore, it is to be understood that although only a single corner section 3 has been illustrated, a cover element 2 can have more than one corner section 3.

Figure 4 also illustrates the embodiment of the flexible joint having a fastening means 14. The fastening means 14 can be used as an additional securing means in construction gaps 26 in which it is not possible to include a strap 22. The fastening means 14 is cylindrical rib 14A attached to the exterior 6A of one of the elongate rectangular members 45. As illustrated in figure 9, the cylindrical rib 14A is received within a corresponding shaped female connector, such as channel 44 affixed to the corresponding structural element 43. In an alternative Hi\jolzik\keep\Speci\P52588 Flexible joint complete.doc 13/04/04 18 embodiment, the fastening means 14 could be shaped as an arrow head.

In figure 4, the structural element comprises one side of a window or door fitting 42. Furthermore, in this situation the hook shaped ribs 10 positioned on the same side of the flexible joint 26 as the fastening means 14 can also be secured against another member 46 which forms part of the window or door frame 42. The elongate rectangular member 47 on the opposite side of the flexible joint 46 to the fastening means 14 engages the other structural element of the construction gap 43A. The cover element 2 includes corner section 3 so as to extend over the wall structure surface 43A that is perpendicular to the face of the window structure 48.

An embodiment of the flexible joint system incorporating a strap 22 is illustrated in figures SA, and 8. The strap 22 acts as a further means for securing the flexible joint 50 within the construction gap 26. In both figures, the flexible joint 50 is secured to the strap 22 using an interlocking attachment system 28. The interlocking attachment system secures a hook shaped rib of the flexible joint 50 into corresponding hook shaped recess 33 incorporated into the strap 22. The hook shaped rib 10 extends the length of the flexible joint 50, while the hook shaped recess 33 has a limited height corresponding to the thickness of the strap 22. It must therefore be understood, that because the strap 22 is placed at various spaced apart intervals up the construction gap 26, as shown in figure 5B, only certain sections of the hook shaped rib 10 adjacent to the hook shaped recess 33 are secured inside the hook shaped recess 33. Consequently, this arrangement secures the flexible joint 50 within the construction gap 26 at various spaced apart locations along the construction gap 26 corresponding the locations at which strap 22 is placed within the H,\jolzik\keep\Speci\P52508 Flexible joint complete.doc 13/04/04 19 construction gap 26.

The strap 22 includes a V-shaped deformation section 30. The V-shaped deformation section 30 allows the strap 22 to undergo a predetermined amount of compression or expansion when the structural elements 21 move relative to one another. In this respect, the V-shaped deformation section 30 is able to flex a predetermined distance. The dimensions of the V-shaped deformation section 30 are determined so as to acconmmodate any movement of the structural elements 21 relative to one another resulting from normal movement of the structure(s) which include the structural elements 21. In this particular embodiment, the V-shaped deformation section 30 is configured to allow a to 7 mm lateral movement between the structural elements 21. Once the structural elements 21 have moved apart further than 5 mm, the strap 22 will be damaged.

Accordingly, significant structural movements may damage the strap 22. Such damage could be used as a warning system that significant structural movement has occurred.

Therefore, the presence of damage to the strap 22 would give a visual indication that further investigation should be undertaken.

A person skilled in the art would appreciate that the strap 22 can be secured to the structural elements 21 of the construction gaps 26 using various means. The strap 22 can be glued, nailed, screwed, hooked or the like to the structural elements 21 of the construction gap 26. When the structural elements are constructed of bricks, concrete blocks of the like, the strap 22 can be placed in the mortar between the layers of bricks or blocks. Likewise, if the structural elements 21 consist of concrete, the strap 22 can be positioned in appropriate locations and the concrete poured around the strap 22.

In one embodiment of the invention, the strap 22 Hi\jolzik\keep\Speci\P5S58B Flexible joint couplete.doc 13/04/04 20 is used as wall ties, particularly brick wall ties, which are typically placed in every forth course of brick on each side of a construction joint 26. For use as a wall tie, the strap 22 is preferably constructed of metal.

A person skilled in the art would appreciate that suitable flexible materials for the cover element 2, flexible element 4 and strap 22 would be selected on the basis of the factors such as desired mechanical properties, degradation properties, economics and manufacturing process. In this respect suitable materials include wood, various polymers, and metals. However, the present invention is preferably constructed of a plastic. The cover element 2 is preferably constructed of a plastic material substantially having UV resistance.

A person skilled in the art would also appreciate that the flexible joint and strap of any of the above embodiments may be manufactured using several suitable techniques. The selection of such techniques is dependent on factors such as the material selection and the material properties. In a preferred embodiment, the flexible joint is constructed of a plastic and is manufactured as an extrusion. The flexible joint can then be cut to any appropriate length.

A person skilled in the art would also appreciate that the dimensions of the flexible joint 50 and strap 22 are chosen to suit the particular application and construction gap dimensions. Accordingly, the flexible joint 50 and strap 22 may be manufactured of any length, height or width. In the instance of manufacturing the flexible joint 50 using extrusion techniques, the flexible joint 50 may be made to any length suitable for the construction gap. Furthermore, the flexible joint including the flexible element 4 and cover element 2 may be constructed of very small sections which then can be Hz\jolzik\keep\Speci\P5258 Flexible joint complete.doc 13/04/04 21 cumulatively placed into the construction gap or one long continuous section of material.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described.

In particular, those skilled in the art would appreciate that any suitable form and shape of cover element could be used to conceal the construction gap. For example, the cover element may include ornamentation or textures.

Furthermore, those skilled in the art would appreciate that any form of members which engage the structural elements of a construction gap and act as a biasing means could be used to function as the flexible element. For example, the flexible element may comprise a central member attached to the centre of the cover element which has several spaced apart lateral engagement portions, the ends of the lateral engagement portions engaging the structural elements of the construction gap. The flexible element may comprise a brush like structure attached to a cover element, having flexible bristles which engage the structural elements of the construction gap.

Furthermore, those skilled in the art would appreciate that any form of strap which includes corresponding connectors for the fastening means of the flexible element could be used to secure the flexible joint within the construction gap.

These and other variations should be understood as falling within the scope of the invention described herein.

In the following claims and the preceding HI\jolzik\keep\Speci\P52588 Flexible joint com letedoc 13/04/04 22 description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Hi\jolzik\keep\Speci\P52568 Flexible joint complete.doc 13/04/04

Claims

2. A flexible joint system according to Claim 1 in which the strap comprises a flat planar member incorporating a deformation element.
3. A flexible joint system according to Claim 1 or Claim 2 in which the deformation section is sized to allow the strap to undergo a predetermined amount of deformation during relative movement of the structural elements.
4. A flexible joint system according to Claim 3 in which the predetermined amount of deformation substantially corresponds to the onset of relative movement between the structural elements which is detrimental to a structure including the structural elements. A flexible joint system according to any one of the preceding claims in which the deformation section of the strap is a biasing means.
6. A flexible joint system according to Claim 5 in which the biasing means is a V- shaped projection.
7. A flexible joint system according to any one of the preceding claims in which the strap is also used as a wall tie in the construction gap.
2007-I 0-16,H:\Specifications\borg.claims.wpd23 -24- 8. A flexible joint system according to any one of the preceding claims comprising, a cover element for concealing the construction gap, the cover element being O attachable to the flexible element. (-i 9. A flexible joint system according to Claim 8 in which the cover element is sized to conceal the construction gap for a predetermined amount of relative movement Sof the structural elements. A flexible joint system according to Claim 9 in which the predetermined amount S 10 of relative movement of the structural elements substantially corresponds to the onset of relative movement to a structure including the structural elements. 11. A flexible joint system according to any one of Claims 8-10 in which the cover element extends a predetermined distance past either side of the two structural elements of the construction gap corresponding to the predetermined amount of relative movement. 12. A flexible joint system according to Claim 11 in which the predetermined distance is between 1 and 13. A flexible joint system according to any one of Claims 8-12 in which the cover element further comprises at least one angled section configured to conceal a construction gap between two structural members having outer surfaces located at an angle to one another. 14. A flexible joint system according to any one of Claims 8-13 in which the cover element is detachable. A flexible joint system according to Claim 14 in which the detachable cover is secured to the flexible element using corresponding attachment means which are independently fixed to the cover element and flexible element. 2007-1 0-16,H:\Specifications\borg.claimswpd,24 16. A flexible joint system according to Claim 15 in which the attachment means are hook shaped connectors. O 17. A flexible joint system according to any one of the preceding claims in which the flexible element comprises two spaced apart planar members which abut \respective structural elements and are joined by biasing means. S18. A flexible joint system according to Claim 17 in which the biasing means is a flexible V-shaped member. C-i 19. A flexible joint system according to any one of the preceding claims in which the flexible element includes engagement portions which engage the two structural elements of the construction gap. 20. A flexible joint system according to any one of the preceding claims comprising, fastening means adapted to fasten the flexible joint system to a corresponding securing means on at least one of the two structural elements. 21. A flexible joint system according to Claim 20 in which the fastening means is located on the flexible element. 22. A flexible joint system according to any one of the preceding claims in which the flexible element is constructed of a flexible material which substantially deforms in response to the movement of the structural elements relative to one another. 23. A warning system for excessive movements of a structure comprising a flexible joint system according to any one of the preceding claims located in the construction gap defined between two structural elements in the structure, the cover element of the flexible joint being sized to conceal the construction gap until the onset of relative movement between the structural elements which is detrimental to the structure, wherein a warning of excessive movements of the structure is indicated by the cover element having moved to a point at which the 2007-10-1 6H:\Specifications\borgclaimswpd,2S -26- 0 construction gap is exposed. ,l O 24. A warning system for excessive movements of a structure comprising a flexible joint system according to any one of Claims 1-22 located in a construction gap defined between two structural elements in the structure, the strap having a Orpredetermined amount of deformation substantially corresponding to the onset of relative movement between the structural elements which is detrimental movements of the structure is indicated by damage to the strap. N 10 25. A warning system for excessive movements of a structure according to Claim 24 in which the cover element of the flexiblejoint also provides a warning according to Claim 23. 26. A strap for a flexible joint system for placement into a construction gap defined between two structural elements, the flexible joint system comprising a flexible element configured to extend into the construction gap, engage each of the structural elements and deform in response to movement of the structural elements relative to one another, wherein the strap is adapted to extend between and be attachable to the two structural elements, the strap having a deformation element which allows the strap to deform, and the strap being interengageable with the flexible element. 27. A flexible joint system substantially as herein before described with reference to the accompanying drawings. 2007-10-1 6H:\Specifications\borgclaims.wpd,26