EXPANSION JOINT

Abstract

An expansion joint for providing a rodent-proof barrier. The expansion joint comprises an elongate core formed of a resiliently deformable material, and a flexible sheath of a barrier material covering at least a part of the elongate portion of the elongate core. The elongate portion of the elongate core is compressible in a direction perpendicular to a line between the first and second ends of the elongate core, the elongate core being arranged to be compressed and inserted into a gap between first and second building structures, and to expand after insertion into the gap so that the expansion joint is held in place within the gap by friction between the surface of the flexible sheath and the surfaces of the first and second building structures.

Claims

1. An expansion joint for providing a rodent-proof barrier, the expansion joint comprising: an elongate core formed of a resiliently deformable material, the elongate core comprising an elongate portion and first and second ends; and a flexible sheath of a barrier material covering at least a part of the elongate portion of the elongate core; wherein the elongate portion of the elongate core is compressible in a direction perpendicular to a line between the first and second ends of the elongate core, the elongate core being arranged to be compressed and inserted into a gap between first and second building structures, and to expand after insertion into the gap so that the expansion joint is held in place within the gap by friction between the surface of the flexible sheath and the surfaces of the first and second building structures.

2. An expansion joint as claimed in claim 1, wherein the elongate portion of the elongate core has a constant cross-section along its length.

3. An expansion joint as claimed in claim 1 or claim 2, wherein the flexible sheath is formed of a woven material.

4. An expansion joint as claimed in claim 3, wherein the woven material is a continuous weave.

5. An expansion joint as claimed in claim 3 or claim 4, wherein the woven material is woven metal wire.

6. An expansion joint as claimed in any of claims 1 to claim 4, wherein the flexible sheath is formed of Kevlar.

7. An expansion joint as claimed in any preceding claim, wherein the elongate core comprises a prefabricated foam tube.

8. An expansion joint as claimed any preceding claim, wherein the flexible sheath is held in place on the elongate core by friction between the flexible sheath and the surface of the elongate core.

9. A method of bridging a gap between first and second building structures using an expansion joint as claimed in any of claims 1 to 8, wherein a width of the elongate portion of the elongate core of the expansion joint in a direction perpendicular to a line between the first and second ends of the elongate core is greater than the width of the gap, the method comprising the steps of: compressing the elongate core in the direction perpendicular to a line between the first and second ends of the elongate core; inserting the expansion joint into the gap; and allowing the elongate core to expand such that the expansion joint is held in place within the gap by friction between the surface of the flexible sheath of the expansion joint and the surfaces of the first and second building structures.

10. A method as claimed in claim 9, further comprising, prior to inserting the expansion joint in the gap, the steps of: selecting an elongate core, the width of the elongate portion of the elongate core of the expansion joint in a direction perpendicular to a line between the first and second ends of the elongate core being greater than the width of the gap; and covering at least a part of the elongate portion of the elongate core with the flexible sheath.

11. A method as claimed in claim 9 or claim 10, further comprising the step of applying a filler layer and/or a finishing layer to the gap to cover the expansion joint.

Description

DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1a shows an expansion gap in a wall;

[0035] FIG. 1b shows a weep hole between bricks in a wall;

[0036] FIG. 2 is a perspective view of an expansion joint according to an embodiment of the invention;

[0037] FIG. 3 shows the expansion joint of the first embodiment installed in a gap between first and second building structures; and

[0038] FIG. 4 is a flowchart describing the installation of the expansion joint shown in FIG. 3.

DETAILED DESCRIPTION

[0039] An expansion joint for providing a rodent-proof barrier in accordance with an embodiment of the invention is now described, with reference to FIG. 2.

[0040] FIG. 2 shows a perspective view of the expansion joint 100. The expansion joint 100 comprises a cylindrical elongate core 101 having an elongate portion 101a with a first end 103a and a second end 103b. The elongate core 101 is formed of polyethylene foam, but in other embodiments of the invention the elongate core 101 may be formed of other resiliently deformable materials, such as other types of polymer foam, or any other material with suitable resiliently deformable properties. The elongate core 101 is a solid tube, but in other embodiments it may be hollow, and/or may be another elongate shape, such as oval, rectangular, C-shaped, or another shape in cross-section.

[0041] The expansion joint 100 further comprises a flexible sheath 102, which covers of the elongate portion 101a of the elongate core 101. The flexible sheath 102 does not cover the first end 103a and a second end 103b of the elongate core 101, but in other embodiments the first end 103a and a second end 103b may be covered by the flexible sheath 102. The flexible sheath 102 is made of woven metal wire, in particular a knitted mesh of stainless steel wire. In other embodiments the flexible sheath 102 may be formed of other materials, for example a polymeric mesh such as Kevlar. In other embodiments of the invention, the flexible sheath 102 comprise a combination of metallic and polymeric threads, for example. The flexible sheath 102 may comprise a continuous weave of material, in other words it is formed of interlocking loops of a single thread (or wire of the like), so that the flexible sheath 102 with no discontinuities or breaks such as would be formed by knots or bonding of the threads of the flexible sheath).

[0042] The elongate core 101 is compressible, and is when uncompressed slightly larger in diameter than the inside of the flexible sheath 102. The elongate core 101 is thus kept in slight compression by the flexible sheath 102, and consequently exerts an expansive force on the flexible sheath 102, keeping the flexible sheath 102 in position on the elongate core 101 by friction between the exterior surface of the elongate core 101 and the interior surface of the flexible sheath 102. In other embodiments the flexible sheath 102 may be fixed in position on the elongate core 101, for example by glue.

[0043] The expansion joint is 2 cm in diameter and 1m in length, but it will be appreciated that many other dimensions of the expansion joint could be used in other embodiments of the invention.

[0044] The installation of the expansion join 100 in a gap between building structures is now described, with reference to FIGS. 3 and 4. The building structures are a first concrete slab 104 and a second concrete slab 105, which have between them a gap G, of width 1.5 cm.

[0045] In a first step, an expansion joint for the gap G is selected (step 301). The expansion joint is selected so that when uncompressed it is has a diameter slightly greater than the width of the gap into which it is to be installed. In the present embodiment, the expansion joint 100 is selected, as it has a diameter of 2 cm, and the gap G has a width 1.5 cm.

[0046] In embodiments of the invention, the expansion joint may be manufactured on-site, i.e. the elongate core inserted into the flexible sheath only after the gap to be filled is known. This allows a suitable length of elongate core and flexible sheath to be selected, possibly by cutting either or both to the required length. In other embodiments, the expansion joint is manufactured off-site.

[0047] The expansion join 100 is then inserted into the gap G (step 302). As the width of the gap G is smaller than the diameter of the elongate core 101, and thus of the expansion joint 100, it the elongate core 101 is compressed as the expansion joint 100 is inserted into the gap G. However, as the elongate core 101 is resiliently deformable, and the flexible sheath 102 is flexible, this is easily done.

[0048] Once in position within the gap G, the expansion join 100, and in particular its elongate core 101, is allowed to expand (step 303). As the width of the gap is less than the width of the expansion joint 100 when uncompressed, the expansion joint 100 (and in particular the elongate core 101 thereof) expands to touch the surface 106 of the first concrete slab 104 and the surface 107 of the second concrete slab 105 that form the gap G, so that it completely spans the gap G. Once expanded as much as it is able the elongate core 101 exerts an expansive force on the surface 106 and 107, via the flexible sheath 102, so that the expansion joint 100 is held in place in the gap G by friction between its surface (in particular the outer surface of the flexible sheath 102) and the surfaces 106 and 107.

[0049] A filler layer 140 and/or a finishing layer 141 is then applied to the gap G, to cover the expansion joint 100. The filler layer 140 may for example be an epoxy resin, and the finishing layer 141 is a material chosen to complement or match the appearance of outer surfaces 142 and 143 of the first concrete slab 104 and a second concrete slab 105, but it will be appreciated that the filler layer 140 and/or finishing later 121 could be various other suitable materials.

[0050] When the expansion joint 100 has been installed, a rodent attempting to pass the expansion joint 100 to enter the gap G will be met by the flexible sheath 102 of the expansion join 100, as the flexible sheath 102 spans the width of the gap G, due to the expansive force of the elongate core 101 pushing it outwards to touch the surfaces 106 an 107 of the gap G. The rodent is unable to penetrate the flexible sheath 102 due to its barrier properties, and so unable to pass the expansion joint 100 to enter the gap G. Further, the rodent will also be prevented from reaching the elongate core 101 of the expansion joint 100 by the flexible sheath 102, and so the rodent is unable to damage the elongate core 101.

[0051] While the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein.

[0052] Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may not be desirable, and may therefore be absent, in other embodiments.