GB2318376A

GB2318376A - Duct cover assembly.

Info

Publication number: GB2318376A
Application number: GB9619695A
Authority: GB
Inventors: Timothy John Blower; Peter Jeffrey Stephenson; James Grenville Bown; Christopher Paul Trivett
Original assignee: Camas UK Ltd
Current assignee: Camas UK Ltd
Priority date: 1996-09-20
Filing date: 1996-09-20
Publication date: 1998-04-22
Also published as: GB9619695D0

Abstract

A concrete duct cover (20) is moulded with a reinforcing frame (22) around its lower edge and is secured to a locating plate (30) by means of a bolt (42) through an aperture (24) formed in the cover. The cover is installed above a duct (10) by positioning the lower section (38) of the assembly locating means (30) on the channel side (14). Once in position, concrete (18) is laid up to the locating plate (30) and the channel side (14), with lugs (44) keying into the concrete to secure the plate (30) when set. To avoid ingress of contaminants, a sealing bead (48) may be located at the top portion of plate 30, with a layer of soft tar (52) infilling above this and other recesses. The cover may be removed by releasing bolts 42. The metal-to-metal contact between plates (22) and (30) prevents cover abrasion under load, which could lead to the cover rocking.

Description

Duct Cover Assemblv This invention relates to a cover assembly for a ground located duct for use particularly, but not exclusively with an access service protection or drainage duct, and a method of installing the cover assembly.

There is a requirement nowadays for service protection or drainage ducts used in roadways and the like to have covers capable of withstanding, for example, a 50 tonne wheel loading without consequential movement or rocking, and also for such covers to be removable to enable access to the ducts.

According to the present invention there is provided a cover assembly for a ground located duct, the assembly comprising a cover having a lateral dimension whereby the cover, in use, extends laterally outwardly of each side of the duct, and locating means adapted to be non-movably secured to each side of the cover whereby to extend over at least a lower face thereof to a location for seating on a respective side of the duct, the locating means being adapted to be non-movably secured on site to cementitious material of a bed for the duct when the material is laid up to the duct and the locating means, whereby the cover locates across the duct and is non-movably secured to the bed thereof.

Preferably non-abrasive, reinforcing means is secured to the cover thereof to define a lower outer edge of each side of the cover, and each of the locating means may be securable to the cover at the location of the respective reinforcing means. The locating means is preferably in the form of a metal plate, and the reinforcing means is also preferably in the form of a metal plate, therefore providing metal to metal contact.

The cover preferably has a through aperture towards each side edge and extending between an upper face and the lower face whereat the aperture is aligned with respective apertures in the locating means and in the reinforcing means. A securing bolt may be locatable through each arrangement of aligned apertures from the upper face of the cover to locate in a securing nut on the locating means, and thereby non-movably secure the latter to the cover.

The locating means preferably also extends substantially over a respective side face of the cover. The latter is preferably formed of a moulded cementitious material such as concrete, whereby the reinforcing means may be secured to the cover during moulding thereof.

The invention further provides a duct comprising a base defining an internal channel, and a cover assembly as described in any of the four preceding paragraphs providing a cover for the duct.

The present invention also provides a method of installing a cover assembly on a ground located duct, the method comprising providing a cover, non-movably securing locating means to each side of the cover whereby to extend at least over part of a lower face thereof, locating the cover across the duct whereby the cover extends laterally outwardly of each side of the duct and the locating means on each side edge of the cover seats on a respective side of the duct, laying a cementitious material up to the duct and the locating means whereby to define a bed for the duct, the locating means being thereby nonmovably secured to the cementitious material, and thereby the cover being nonmovably secured to the bed of the duct.

Preferably a removable bolt secures the locating means to the cover, whereby removal of the bolt enables removal of the cover from the bed of the duct and thereby from the duct but with the ability to reposition the cover nonmovably in relation to the bed of the duct by reinsertion of the bolt.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings, in which: Fig. 1 is a schematic end elevation of a drainage duct with a cover assembly according to the invention; and Fig. 2 is an enlargement of detail A of Fig. 1.

Referring to the drawings, a duct 10 has a U-shape in cross-section to define an internal channel 12 with respective upstanding sides 14 presenting top seating faces 16. The duct 10 is adapted to be embedded in a concrete bed 18 as hereinafter described.

A cover 20 for the duct 10 is preferably a concrete moulding which has a lateral dimension such that, when seated on the duct 10, the cover 20 extends laterally outwardly of the latter. During moulding, the cover 20 has a reinforcing angle plates 22, for example of steel, formed therewith to define respective lower side and bottom edges of the cover 20. The latter is also formed with a through aperture 24 towards each side edge extending between a recess 26 in an upper face 28 of the cover 20 to the plate 22 at the lower edge, an aperture being formed in the plate 22 in alignment with the aperture 24.

Prior to installing the cover 20, a seating plate 30, preferably of steel, is non-movably secured to each side of the cover 20. The plate 30, in section, has a profile similar to a section through the respective side of the cover 20, consisting of a section 32 extending across a side face 34 of the cover 20 but spaced slightly therefrom, a section 36 extending across the lower side of the plate 22, and a section 38 extending inwardly of the section 36 to a location where the section 38 can seat on the seating face 16 of the respective channel side 14. The section 36 has an aperture to align with the aperture in the plate 22, and the section 36 has a securing nut 40 secured to its lower face at the location of the aperture. A bolt 42 locates through each of the cover apertures 24 and through the aligned apertures in the plates 22, 30 to engage with the securing nut 40 and thereby, when tightened, non-movably secure the seating plate 30 to the cover 20. The plate has at least one lug 44 extending outwardly from the section 32.

After securing of the plate 30 to the cover 20, the assembly is laid on top of the channel sides 14 with the plate sections 38 engaging on respective beds 46 of epoxy on the seating faces 16. The joints between adjacent plates 30 are taped prior to laying concrete on site up to the respective seating plates 30 and the respective channel sides 14. The lugs 44 key into the concrete to nonmovably secure the plates 30 thereto.

By the non-movable securing of the seating plates 30 to the covers 20 and subsequently the seating plates 30 to the concrete bed 18, the cover 20 is effectively non-movably secured to the bed 18 and thereby enables the cover 20 to accommodate the required level of wheel loading without rocking.

When access to the duct 10 is required, the cover 20 can be removed by releasing the bolts 42. The method of securing ensures that, when the cover 20 is replaced, the bolt apertures can be correctly aligned with the securing nuts 40 to thereby regain the non-rocking fixing. The apertures may be slightly enlarged to facilitate locating the securing nut 40 with the bolts 42. The metal to metal contact between the plate 22 and the plate 30 avoids abrasion of the material of the cover 20 at the lower edges should there be any slight movement which may then lead to rocking under load. The provision of the plates 22 and 30 at an angle on the lower edge of the cover 20 facilitates the introduction of concrete around the plates 30.

To avoid ingress of contaminants, a sealing bead 48 is located between each of the sections 32 of the respective plates 30 and the respective side face 34. Above the beads 48, in the recesses 26, and in other recesses 50 for lifting purposes, soft tar 52 can be cold poured, enabling subsequent removal as required.

Various modifications may be made without departing from the invention. For example the configuration of the cover, the reinforcing plates and the seating plates, and consequently the position of the securing bolts, may differ from that described and shown.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

aaims:-

1. A cover assembly for a ground located duct, the assembly comprising a cover having a lateral dimension whereby the cover, in use, extends laterally outwardly of each side of the duct, and locating means adapted to be nonmovably secured to each side of the cover whereby to extend over at least a lower face thereof to a location for seating on a respective side of the duct, the locating means being adapted to be non-movably secured on site to cementitious material of a bed for the duct when the material is laid up to the duct and the locating means, whereby the cover locates across the duct and is non-movably secured to the bed therefor.

2. A cover assembly according to claim 1, wherein the locating means is in the form of a metal plate.

3. An assembly according to claim 1 or 2, wherein non-abrasive reinforcing means is secured to the cover to define a lower outer edge of each side thereof.

4. An assembly according to claim 3, wherein each of the locating means is securable to the cover at the location of the respective reinforcing means.

5. An assembly according to claim 3 or 4, when dependent on claim 2, wherein the reinforcing means is in the form of a metal plate, therefore providing metal to metal contact with the plate of the locating means.

6. An assembly according to any of claims 3 to 5, wherein the cover has a through aperture towards each side edge and extending between an upper face and the lower face whereat the aperture is aligned with respective apertures in the locating means and in the reinforcing means.

7. An assembly according to claim 6, wherein a securing bolt is locatable through each arrangement of aligned apertures from the upper face of the cover to locate in a securing nut on the locating means, and thereby non-movably secure the latter to the cover.

8. An assembly according to any of claims 3 to 7, wherein the cover is formed of a moulded cementitious material, whereby the reinforcing means may be secured to the cover during moulding thereof.

9. An assembly according to claim 8, wherein the cover is formed of concrete.

10. An assembly according to any of the preceding claims, wherein the locating means extends substantially over a respective side face of the cover.

11. A duct comprising a base defining an internal channel, and a cover assembly as claimed in any of the four preceding claims providing a cover for the duct.

12. A method of installing a cover assembly on a ground located duct, the method comprising providing a cover, non-movably securing locating means to each side of the cover whereby to extend at least over part of a lower face thereof, locating the cover across the duct whereby the cover extends laterally outwardly of each side of the duct and the locating means on each side edge of the cover seats on a respective side of the duct, and laying a cementitious material up to the duct and the locating means whereby to define a bed for the duct, the locating means being thereby non-movably secured to the cementitious material, and thereby the cover being non-movably secured to the bed of the duct.

13. A method according to claim 12, including securing the locating means to the cover by a removable bolt, whereby removal of the bolt enables removal of the cover from the bed of the duct and thereby from the duct but with the ability to reposition the cover non-movably in relation to the bed of the duct by reinsertion of the bolt.

14. A cover assembly for a ground located duct, substantially as hereinbefore described with reference to the accompanying drawings.

15. A ground located duct substantially as hereinbefore described with reference to the accompanying drawings.

16. A method of installing a cover assembly on a ground located duct substantially as hereinbefore described with reference to the accompanying drawings.

17. Any novel subject matter or combination including novel subject matter disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.