The present invention relates to concrete expansion joints. More particularly, the present invention relates to a support assembly for an expansion joint strip and a method for installing an expansion joint strip in a concrete slab.
Concrete floors and paving typically comprise a number of concrete slabs. The concrete slabs are typically designed for movement relative to each other to avoid formation of cracks in the floor or paving which would otherwise form with thermal expansion and contraction of the concrete slab and movement of supporting foundations. Concrete slabs are typically separated from each other by concrete expansion joints which usually comprise a compressible expansion joint strip. Compressible expansion joint strips fill the gaps between concrete slabs while allowing movement toward and away from each other.
Devices for positioning an expansion joint strip and formation of a corresponding expansion joint between concrete slabs are disclosed in U.S. Pat. No. 6,598,364 B1 and Danley Construction Products Pty Ltd and Connolly Key Joint Pty Ltd websites www.danley.com.au and www.connollykeyjoint.com respectively. The corresponding expansion joint forming devices are typically cumbersome and time consuming to erect.
According to one aspect of the present invention there is provided a support assembly for an expansion joint strip, said assembly comprising: an elongate base strip including at least two laterally spaced locating walls; a plurality of discrete support modules each being detachably connected to the locating walls at longitudinally spaced positions along the base strip; and means for adjusting the height of the expansion joint strip relative to at least one of the support modules.
Preferably the support assembly also comprises an expansion joint strip cover adapted to support the expansion join strip and being arranged to be supported by one or more of the support modules. More preferably each of the modules includes a U-shaped channel configured to cradle the expansion joint strip cover.
Preferably the height adjustment means includes a pin being designed to locate at one of a plurality of different height positions relative to the corresponding support module. More preferably the pin is received in one of a plurality of locating holes in the support module, the strip cover being designed to rest on the pin to support the expansion joint strip at the required height. Even more preferably the pin is enlarged at one end for press-fit engagement with said one of the locating holes.
Preferably the locating walls are each in the form of stiffening ribs designed to strengthen the base strip.
Preferably the support modules include a pair of spaced support legs each being perforated to promote the flow of concrete and encasing of said modules.
Preferably said locating walls include a pair of outer locating walls and a central locating wall. More preferably the base strip includes a groove or slot underlying the central wall and designed to allow lateral movement of the strip.
Preferably the support assembly also comprises another base strip joined to said base strip at an expansion joint juncture.
According to another aspect of the invention there is provided a method of installing an expansion joint strip in a concrete slab, said method comprising the steps of: providing an elongate base strip having at least two laterally spaced locating walls; providing a plurality of discrete support modules; fitting two or more of the support modules to the locating walls of the base strip at spaced longitudinal positions along the base strip; placing the expansion joint strip upon one or more of the modules and adjusting the height of said strip relative to at least one of said modules; and pouring concrete to at least partly bury the base strip, the support modules and the expansion joint strip.
Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the figures.
A preferred embodiment of the present invention will now be described, by way of example only, with reference to the following figures in which:
a is a perspective view of a base strip from the assembly of
b is an end elevational view of the base strip of
a is a perspective view of an expansion joint strip support assembly similar to that of
b is an end elevational view of an alternative strip cover to that of
b show an expansion joint strip support assembly of the present invention in the form of support assembly 10. The support assembly 10 comprises an expansion joint strip support module in the form of support module 12, a base strip 14 and an expansion joint strip cover in the form of strip cover 16. The support module 12 attaches to the base strip 14 as shown in
The support assembly 10 shown in
The position of an upper surface 136 of the compressible expansion joint strip 20 relative to the upper surface 104 of the base strip 14 is adjusted by passing a locating pin 138 through opposed holes 38 and 40 of the U-shaped channel 24 as shown in
Features of the support module 12, base strip 14 and strip cover 16 will be described in more detail before providing a more detailed description of assembly of the support assembly 10. The support assembly 10 comprises an expansion joint strip locating portion in the form of a U-shaped channel 24 and support legs in the form of planar legs 26 and 28. The U-shaped channel 24 comprises opposed side walls 32 and 34 and an adjoining base 36. The U-shaped channel 24 also includes adjustment means in the form of opposed holes 38 and 40 formed in respective side walls 32 and 34.
The planar leg 26 comprises 3 adjoining planar leg portions in the form of adjoining leg portions 46, 48 and 50. The adjoining planar leg 28 similarly comprises 3 adjoining planar leg portions in the form of adjoining leg portions 50 to 54 and 56. Although not shown in
The adjoining leg portions 46 and 52 comprise attachment means for attachment to the base strip 14. The attachment means of the adjoining leg portions 46 and 52 is in the form of respective locating slots 60 and 62. Each of the locating slots 60 and 62 comprises locating slot walls 64 and 66, and 68 and 70 respectively. The walls 64, 66, 68 and 70 are resiliently deformable for attachment to the base strip 14. Formed on the inner surface of walls 64 and 70 are engaging surfaces in the form of barbs 74. The barbs 74 are designed for engagement with corresponding engaging features of the base strip 14 which are described below.
The base strip 14 is also extruded and includes 2 outer locating walls in the form of outer locating walls 80 and 82 and a central locating wall in the form of central locating wall 84. The outer and central locating walls are the attachment means of the base strip 14 for attachment to a support module such as support module 12. The central locating wall may also function to elevate the reinforcing mesh which reduces or in some cases may replace the need for reinforcing mesh support cradles.
Outer locating walls 80 and 82 include on their outer surfaces 86 and 88 respectively engaging surfaces corresponding to the engaging surfaces of the locating slots 60 and 62 in the form of barbs 90. As can be seen from
The height of the outer locating walls 80 and 82 and the depth of the corresponding respective locating slots 60 and 62 is such that the locating walls are fully received within the corresponding locating slots before free ends 100 and 102 of the planar legs 26 and 28 (see
The base strip 14 includes outer regions in the form of recessed regions 110 and 112. The recessed regions 110 and 112 have corresponding respective recessed surfaces 114 and 116 which are offset relative to the upper surface 104 of the base strip 14. The base strip 14 also includes recess strips in the form of recess strips 120 and 122 which are formed in an underneath side of the base strip 14. Finally, the base strip 14 includes a groove in the form of a V-shaped groove 106 (see
The alternative use of the base strip 14 shown in
The alternative use of the base strip 14 shown in
An alternative expansion joint strip support assembly in the form of support assembly 140 is shown in
The support assembly 140 also includes a concrete slab locating rod 150 (see
The support module 142 is formed as described above in relation to the support module 12 by cutting 80 mm lengths from a correspondingly shaped extrusion. The support module 12 includes a planar leg 160 which is essentially identical to the planar leg 26 of the support module 12. The planar leg 160 includes intersecting leg portions 162, 164 and 166. The intersecting leg portion 162 includes a locating slot 170 formed between locating slot walls 172 and 174. Barbs 176 are formed on an inner surface of the locating slot wall 172 as described above in relation to the support module 12.
The support module 142 includes an expansion joint strip locating portion in the form of U-shaped channel 180. The U-shaped channel 180 includes side walls 182 and 184 and an adjoining base 186. The side wall 182 extends from the base 186 upwardly beyond the intersecting leg portion 166. An upper end of the extension of the side wall 182 is in the form of a strip cover locating projection 190.
The support module 142 also includes attachment means in the form of a locating slot 192 formed between a locating slot wall 194 and an outer surface of the side wall 182 and its corresponding upward extension. Formed on the inner surface of the locating slot 192 are engaging surfaces in the form of barbs 196. The locating slot 192 is designed for engagement with the central locating wall 84 of the base strip 144 as described in relation to the locating slot 170.
The side wall 182 and its corresponding upward extension which connects to the intersecting leg portion 166, as well as the base 186 of the U-shaped channel 180 also functions as a second support leg of the support module 142.
In addition to being a different height than the strip cover 16 of the support assembly 10, the strip cover 146 includes an axial flange 200. The axial flange 200 attaches to an outer surface of a side wall 202 of the strip cover 146. The axial flange 200 provides a module locating slot 204 for receipt of the strip cover locating projection 190 of the support module 142. The axial flange 200 prevents the strip cover 146 and corresponding compressible expansion joint strip 148 from tilting away from the strip cover locating projection 190. The axial flange 200 also stiffens the strip cover 146 to prevent distortion, particularly in a plane which is parallel with the base 186 of the U-shaped channel 180. The axial flange 200 also increases torsional stiffness of the strip cover 146 about its longitudinal axis.
An alternative strip cover 147 is shown in
The strip cover 16 of the support assembly 10 and the strip covers 146 and 147 of the support assembly 140 can be used independently of the corresponding support modules 12 and 142 and base strips 14 and 144 to form an expansion joint. The strip covers 16, 146 and 147 sufficiently increase the rigidity of the corresponding respective compressible expansion joint strips 20, and 148 and 149 to enable the assembled strip covers and compressible expansion joint strips to be inserted into wet concrete. Advantages provided by remaining components of the support assemblies 10 and 140 as described throughout the specification may be considered unnecessary for a particular application. If so, this alternative use of the assembled strip covers and compressible expansion joint strips enables expansion joints to be formed more easily and cost effectively.
The locating rod 150 includes a locating sleeve 206 and a corresponding rod 208. As can be seen from
The locating sleeve 206 includes a locating rod locator 220 for attachment of the locating rod 206 to the base strip 144. The locating rod locator 220 is integrally formed with the locating sleeve 206 and includes at an end remote from the locating sleeve a locating slot 222 which is described in the relation to the locating slot 170. The locating slot 222 is designed for removable attachment to the locating slot wall 172 as described above in relation to the location slot 170 and locating slot wall 172.
For some applications the strip cover 146 does not include holes in its walls but is marked for formation of holes through its walls and also through the compressible expansion joint strip 148 located between the strip cover side walls. These holes (not shown) are designed for passage through the strip cover 146 and corresponding compressible expansion joint strip 148 of the locating rod 150. The holes in the strip cover and compressible expansion joint strip are usually more easily formed prior to assembly of the strip cover and support module 142 using an appropriate tool.
The support module 142 is attached to the base strip 144 as described above in relation to the support assembly 10. The strip cover 146 or alternative strip cover 147 and associated respective compressible expansion joint strip 148 or 149 is then fitted into the U-shaped channel 180 so that the strip cover locating projection 190 slides upwardly through the module locating slot 204. With the strip cover 146 and support module 142 assembled as shown in
The locating rod 150 is inserted through holes in the strip cover and expansion joint strip 148 and then attached to the base strip 144 as shown in
Referring to
After concrete is poured on both sides of the compressible expansion joint strip 148 it sets around the locating sleeve 206 and locating rod 208. After the concrete slabs 240 and 242 set they will move relative to each other in response to changes in temperature and movement of the supporting floor or ground. Movement of the concrete slabs normally of the compressible expansion joint strip 148 is accommodated by compression and expansion of that strip and axial movement of the locating rod 208 within the locating sleeve 206. Movement of the slabs 240 and 242 in a direction aligned with a longitudinal axis of the base strip 144 lies is accommodated by lateral movement of the locating rod 208 within the locating sleeve 206.
As can be seen in
Termites typically pass from the ground into a building via its walls by passing upwardly through expansion joints of corresponding concrete slabs. The base strips 14 and 144 of
Support assemblies 10 and 140 can be joined to corresponding support assemblies which, for example, extend normally of those support assemblies for intersection of corresponding expansion joints. One example of intersecting support assemblies is shown in
With the support assemblies 10 and 10′ positioned as shown in
The base strip locator 280 may, for example, in place of the base strip locating lug 284 include another locating slot (not shown) identical to the locating slot 282 but designed for attachment to outer locating walls 80′ or 82′ of the base strip 14′.
Support assemblies 10 and 140 can also be joined to corresponding support assemblies which are aligned with those support assemblies for end to end connection of corresponding expansion joints. End to end connection of base strips 14 is shown in
Support assemblies 10 and 140 of these embodiments of the present invention provide a number of advantages:
(a) quick and easy assembly involving placement of freestanding integrally formed support modules 12 and 142.
(b) sealing of an expansion joint from underneath abutting concrete slabs to prevent termites or moisture passing upwardly through the expansion joint; and
(c) quick, easy and discrete adjustment of upper surfaces of the compressible expansion joint strips 20 and 148.
All publications mentioned in this specification are herein incorporated by reference. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed anywhere before the priority date of each claim of this application.
It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. For example, an inverted T-shaped support leg may replace the planar legs 26 and 28 of the support assembly 10, in which case, the base strip 14 would not include the central locating wall 84. This alternative support leg could, for example, attach to the adjoining base 36 of the U-shaped channel 24. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.
It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.
Number | Date | Country | Kind |
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2004904549 | Aug 2004 | AU | national |
This application is a national stage application of International Application No. PCT/AU2005//001218, filed on Aug. 12, 2005 which claims priority to, and the benefit of, Australian Provisional Application No. 2004904549, filed Aug. 13, 2004, the entire content of which is hereby incorporated by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/AU2005/001218 | 8/12/2005 | WO | 00 | 3/19/2008 |