GB2522701A

GB2522701A - Improvements in or relating to a trench drain

Info

Publication number: GB2522701A
Application number: GB1401853.5A
Authority: GB
Inventors: Simon Francis Godwin Bradbeer; Ian Gell
Original assignee: Alumasc Ltd
Current assignee: Alumasc Ltd
Priority date: 2014-02-04
Filing date: 2014-02-04
Publication date: 2015-08-05
Also published as: WO2015118286A1; GB201401853D0

Abstract

A trench drainage channel support 10 comprises a two-part bridge member 14 for insertion through opposing side walls 80 of a trench drainage channel 12 below a grating 50. A support element 16 extends from each bridge member part 22, 24, and an engagement element 18 engages a ground support member 20. Due to the bridge member 14 extending through the side walls 80 of the drainage channel 12, a thinner walled drainage channel 12 can be utilised, in this case preferably being of pressed metal. The bridge member 14 thus prevents or limits outward splaying of the opposing channel walls, as well as supporting the drainage channel 12. Later embodiments relate to a trench channel grating support, a pressed metal drainage channel, a channel assembly, a method of rigidifying the metal channel and a method of installing the channel assembly

Description

Improvements In Or Relating To A Trench Drain The present invention relates to a trench drainage channel support, a trench drainage channel grating support, a pressed-metal trench drainage channel, and a trench drainage channel assembly utilising such a pressed-metal drainage channel, a said drainage channel support, and preferably also a said gating support. The invention also relates to a method of rigidifying such a pressed-metal trench drainage channel, and to a method of installing a said trench drainage channel assembly.

Trench drains, typically being linear units, are well known for providing drainage for excess rain water from a ground surface. Such drains provide a channel for the water to run from the upper ground surface into a connected sewer system. The drains are generally provided with a cover element, such as a grating, so that the completed drain lies flush with the ground above.

Trench drain channels must he recessed into (lie ground. A trench is usually dug. and the channel inserted therein. However, the trench and/or the upper surface of the ground is rarely level, and the drainage channel must be either positioned level or typically with a slight fail which meets local building regulations.

Channel supports, called chairs', are known and these are configured to seat the drainage channel thereon. However, the drainage channel does not have much in the way of lateral support to prevent or limit sideways tilting or tipping.

hi yet another consideration, any ground support for a drainage channel which is engaged with a chair' must be suitably low that a ground surface finishing layer, such as concrete, blocks or slahs, can he laid and flushly meet an upper edge of the drainage channel. If a chair' is too high, the ground support will foul the finishing layer.

Additionally, drainage channels are typically formed of heavy weight material, such as polymer concrete. Such material is dense and thus unwieldy to lift and manoeuvre.

In particular, long lengths of drainage channel cannot he formed, due to health and safety requirements.

Furthermore, such dense material is prone to damage, such as chipping and cracking.

during storage. transport and installation.

Yet still further, such drainage channels are not stackable in order to improve storage and transportation.

Thc present invention seeks to provide a solution to all of these problems.

According to a first aspect of the present invention there is provided a trench drainage channel support comprising a two-part bridge member for insertion through opposing side walls of a trench drainage channel below a grating. a support clement extending from each bridge member part, and an engaging clement for engaging a ground support member.

Preferable and/or optional features of the first aspect of the invention are set forth in claims 2 to 19. inclusive.

According to a second aspect of the invention, there is provided a modular trench drainage channd support comprising a bridge member for insertion through opposing side walls of a trench drainage channel below a grating, a support element slidably receivable on each end of the bridge member, and an engaging element on each support element for engaging a ground support member.

According to a third aspect of the present invention, there is provided a trench drainage channel grating support comprising a two-part bridge mcmhcr for insertion through opposing side walls of a trench drainage channel below a grating, and a grating engagement member for engaging a grating with the at least one of the parts of the bridge member.

Preferable and/or optional features of the third aspect of the invention are set forth in claims 23 to 30, inclusive.

According to a fourth aspect of the present invention, there is provided a pressed-metal trench drainage channel comprising opposing side walls and a base which is contiguous with the side walls, the side walls tapering in a converging direction towards the base to enable nested stacking for storage and/or transportation.

Preferably, each side wall includes a Hp at or adjacent to its upper free edge for supporting a removable grating.

According to a fifth aspect of the present invention, there is provided a trench drainage channel assembly comprising a pressed-metal trench drainage channel in accordance with the third aspect of the invention, and two or more spaced-apart trench drainage channel supports according to the first aspect of the invention received through opposing side walls of the pressed-metal trench drainage channel.

Preferable and/or optional features of the fifth aspect of the invention are set forth in claims 36 to 39, inclusive.

According to a sixth aspect of the present invention there is provided a method of rigidifying a pressed-metal trench drainage channel comprising the step of: a] interengaging opposing side walls of thc pressed-metal trench drainage channel by inserting a trench drainage channd support in accordance with the first and/or second aspects of the invention through the said side walls.

Preferably, the method further comprises the step of interengaging spaced apart said trench drainage channel supports with outlying stiff strut members to increase longitudinal and lateral trench drainage channel stiffness.

According to a seventh aspect of the present invention there is provided a method of installing a trench drainage channel assembly in accordance with the fifth aspect of the invention, the method comprising the steps of: a] inserting first and second trench drainage channel supports through opposing side walls of a pressed-metal trench drainage channel; and b] using ground support mcmbcrs engagcd with thc engaging elements of the trench drainagc channel supports to sct longitudinal and/or lateral orientations of the trench drainage channel.

The invention will now he more particularly described, by way of example on'y, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a first embodiment of a drainage channel support, in accordance with the first aspect of the invcntion and forming part of a drainage channel assembly in accordance with the fifth aspect of the invention; Figure 2 is an exploded side elevational view ol the drainage channel support; Figure 3 is a perspective view from above of one embodiment of a drainage channel grating support, in accordance with the third aspect of the invention and also forming a prefcrrcd part of the drainage channel assembly in accordance with the fifth aspect of the invention; Figure 4 is an exploded plan view of the drainage channel grating support.; Figure 5 is a side perspective view of one embodiment of a pressed-metal ncstablc drainage channel, in accordance with the fourth aspect of the invention; Figure 6 shows a p'urality of the pressed-metal drainage channels, when nested for ease of storage and/or transportation; Figure 7 shows a side elevational view of the drainage channel assembly, in accordance with the fifth aspect of the invention and utilising two drainage channel supports and a drainage channel grating support; Figure 8 is a perspective end view from above of the drainage channel assembly. including a grating; and Figure 9 is a perspective view of a second embodiment of a drainage channel support, in accordance with the second aspect of the invention and forming part of a drainage channel assembly in accordance with the fifth aspect of the invention.

Referring firstly to Figures 1 and 2 of the drawings, there is shown a first embodiment of a trench drainage channel support 10 which is specifically adapted for use with a, preferably linear, pressed-metal drainage channel 12 embeddable in a ground trench.

The trench drainage channel support 10 comprises a two-part bridge member 14, a support element 16 at each end of the bridge member 14, and an engagement. element 18 to which a ground support member 20 is engagaffle.

The two-part bridge member 14 is preferably cast or moulded metal and includes an elongate female member part 22 and an elongate male member part 24. The female member part 22 is preferably formed with an elongate female body 26 having an access opening 28 at its free distal end and a, preferably bottomed, recess which extends from the access opening 28 along at least a majority of the longitudinal extent of the female body 26.

The male member part 24 is preferably formed with an elongate stepped male body 30. a distal stepped part 32 being at least substantially complementarily shaped to be slidably receivable through the access opening 28 and into the bottomed recess of the female body 26.

A proximal stepped part 34 of the stepped male body 30 provides a female-body stop 36 against which the female member part 22 is abutiable once the male member part 24 is fully engaged. By having the female-body stop 36 off-centre in a longitudinal direction relative to the two-part bridge member 14, a greater length of the male member part 24 can he received by the fcrnae member part 22, therehy improving rigidity and stiffness.

It is prefcrred that the female and male memher parts 22, 24 include 1ateraly-extending alignable apertures 38 partway along their longitudinal extents, and in the case of the male member part 24, on the distal stepped part 32.

Beneficially, the male-member aperture 38a may havc a screw-threaded bore to threadingly engage with a headed screw-threaded fastener 40, which is advantageous as will be understood hereinafter. However, other kinds of locking element may be utilised, in addition or alternatively to the screw-threaded fastener 40. For example. a headed thcking pin may he utilised which can simply he dropped through the respective apertures 38, once aligned.

The alignable apertures 38, once locked together via a suitable locking clement 40, prevent or limit unintended linear separation of the female and male member parts 22, 24.

The female-member aperture 38h may beneficially he larger than the male-member aperture 38a, enabling the longitudinal extent of the trench drainage channel support to be adjusted. Advantageously, this allows the trench drainage channel support 10 to be used in combination with a variety of draiiiage channels 12 having different widths.

To improve die rigidity ol the drainage channel 1 2 as will he understood better hereinafter, each of the female and male member parts 22, 24 may include a bridge stop 42 at their proximal ends. In this ease, the bridge stop 42 is an integrally formed outwardly extending flange or collar 44 which extends laterally around the respective ends of the female and male bodies 26. 30.

Although the flange or collar 44 is continuous, it may be discontinuous, andlor it may be a tooth or teeth, or other forms of projection, such as a step or shoulder.

The flange or collar 44 is interposed between the two-part bridge member 14 and the respective support elements 16, being preferably contiguously formed therewith. Each support element 16 in this embodiment is in the form of a depending arm 46 which drops from the at least substantially planar extent of the bridge member 14.

Beneficially, each depending aim 46 preferably returns slightly, whereby an included interior angle between the depending arm 46 and the bridge member 14 is acute or less than 90 degrees.

lii this embodiment, each depending arm 46 includes an opening, being preferably an aperture 48 to reduce material. However, the opening 48 may be dispensed with, or may be a bottomed recess instead of an aperture, as necessity dictates.

Although a depending arm 46 is preferred, other kinds of support element 16 may be considered. For example, the support element may simply be a nub or block on which the engagement element 18 is provided. However, a significant benefit associated with the depending arm 46 is the ability to space the engagement element 18 away and below an intended plane of a grating 50 to be mounted on the installed drainage channel 12, as will become clear hereinafter.

An engagement body 52 of each engagement element 18 is integrally formed as one-piece contiguously at a distal end of the respective depending arm 46. A first support opening 54. in this case in the form of a through-aperture 56. is provided in the engagement body 52. An axial extent of the first support opening 54 is preferably parallel or substantially parallel with a longitudinal extent of the associated depending arm 46.

A first locking device 58 is provided br engaging the ground support member 20 when received therein. In this case, the locking device 58 is a tool-less releasable screw-threaded fastener 60 having a manually gripable head 62 for tightening or releasing. The fastener 60 is screw-threadingly receivable in the engagement body 52, so as to be projectable into the first support opening 54.

It is beneficial that the locking device 58 is preferably tool-less, allowing faster installation and easier access when presented with a narrower trench or close side walls.

To improve torsional rigidity and to prevent or limit undue flex of the drainage channel 12 along its longitudinal extent, it is also advantageous that the engagement body 52 includes a second support opening 64 oriented such that the first and second support openings 54, 64 are mutually perpendicular.

Similar'y to the first support opening 54, the second support opening 64 is a through-aperture 66 having an unstepped bore.

A second locking device 68 is provided for engaging a stiff strut member 70, when received therein. The second locking device 68 is again preferably a tool-less releasable screw-threaded fastener 72 having a manually gripable head 74 for tightening or releasing. The fastener 72 is screw-threadingly receivable in the engagement body 52, so as to be projectable into the second support opening 64.

The fasteners 60, 72 of the first and second locking devices 58. 68 preferably have longitudinal axes which overlap or intersect. In this case, the thngitudinal axis of the first fastener 60 is perpendicular or substantially perpendicular to the depending arm 46, and the longitudinal axis of the second fastener 72 is inclined upwardly towards the bridge member 14. Again, this alTangelnent allows for easier manual access by an installer.

Although beneficially enclosed, the first and/or second support openings 54, 64 may be slotted or include a slit, providing the ground support member 20 and/or a stiff strut member 70 can be securely received therethrough.

Relerring iiow to Figures 3 and 4, there is shown one embodiment of a grating support 176 for a trench drainage channel 12. Advantageously, a number of elements of the grating support 176 are similar or identical to those of the trench drainage channel support 10, and as such the same references are utilised with 100' added. Further

detailed description is thus omitted.

The grating support 176 comprises the two-part bridge member 114, and a grating engagement member 178 for engaging a grating 50 with the at least one of the parts of the bridge member 114. As described above, the two-part bridge member 114 is preferably of rigid cast or moulded metal and includes an elongate female member part 122 along with an elongate male member part 124 slidally receivable in the female member part 122.

With the male member part 124 slid into the female member part 122 up to the female-body stop 136 at or adjacent to its proximal end, the laterally-extending alignable apertures 138 can receive the grating engagement member 178 to prevent or limit unintentional linear separation.

The grating engagement member 178 in this embodiment is preferably a headed screw-threaded fastener 140 which is thrcadingly cngagable with at least one of the coaxially aligned apertures 138. As before, however, other kinds of grating engagement member can he considered, such as a slidahly receivahk locking pin.

To prevent or inhibit undue outward fiexion of the drainage channel side walls 80. the use of the bridge stops 142 is again beneficial, although not nccessanly essential. As above, each stop 142 may conveniently be a laterally outwardly projecting integral flange 144 which may extend continuously around the lateral perimeter of female and male member parts 122, 124.

Projecting externally along the longitudinal axis from the flanges 144 extend gripping elements 116. These are preferably formed as handles 146, advantageously allowing an installer to readily insert through a drainage channel 12.

RefelTing now to Figures 5 and 6. one embodiment of a trench drainage channel 12 is shown. Such a trench drainage channel 12 prelerahly has a uniform or substantially uniform cross-sectional lateral extent over at least a majority of its longitudinal extent.

The drainage channel 12 is also advantageously formed of thin-walled pressed-metal, such as galvanised steel, and is thereby much lighter and more robust against dropping or mishandling than traditionally used drainage channels, typically being cast from polymer concrete.

The pressed-metal drainage channel 12 has the opposing side walls 80 and a base 82 which is contiguously formed with the side walls 80. The side walls 80 beneficially taper in a converging direction towards the base 82 to enable nested stacking for storage and/or transportation. as best shown in Figure 6.

The base 82 in this case is generally V-shaped to assist with flow by imparting lateral flow movement during longitudinal flow movement. However, other shapes of base may he considered, such as fiat or dished.

To support the grating 50, each side wall 80 includes an outwardly projecting lip or shoulder 84 at or adjacent to its upper free edge 86. An interior platform surface 88, in this case extending along at least a majority of the longitudinal extent of the drainage channel 12, is thus provided on which the grating 50 is removably seatable.

Just below each lip or shoulder 84, a wall opening 90 is provided for eoniplementarily receiving the female and male member parts 22, 24: 122, 124 of the two-part bridge members 14; 114 of the drainage channel support 10 and/or the grating support 176.

By utilising substantially identical profiles and dimensions, the two-part bridge members 14: 114 of the drainage channel support 10 and the grating support 176 can be interchangeably received as required through the wall openings 90.

hi use and with rcfcrence to Figures 7 and 8, a trench drainage channel assembly 92 can be formed utilising the aforc-describcd drainage channel 12, a plurality of the drainage channel supports 10. and in this case, a single one of the grating supports 176.

Initially, the bridge member 14 of each drainage channcl support 10 is separated, and the female and male member parts 22, 24 are slid through respective opposing wall openings 90. typically at the ends of the drainage channel 12. The female and male member parts 22, 24 are inserted through the opposing side walls 80 until their bridge stops 42 abut (he exterior surfaces 94 of the side walls 80, and until the female member part 22 contacts the female-body stop 36 of the male member part 24.

By positioning the wall openings 90 just below each lip 84 of the side wails 80, with the female and male member parts 22. 24 in position, the bridge stops 42 also provide supplementary grating support, improving the load bearing capability of the drainage channel 12.

Once positioned, the locking element 40 can be inserted into the aligned apertures 38 to releasably engage the two-part bridge member 14 with the drainage channel 12.

To provide the drainage channel 12 with a required fall, an elongate ground support member 20, in this case being a length of Rebar RTM or other kind of rigid metal rod, is slidably received in each first support opening 54 of each engagement body 52. By utilising a drainage channel support 10 at or adjacent to at least each end of the drainage channd 12, and by locking each ground support member 20 at its required height via the respective first locking devices 58, the required fall for water flow can be set. The depending arms 46 also beneficially allow spacing of the upper ends of the ground support members 20 below the lips 84, thereby accommodating a ground surface layer, such as slabs or paving, once the drainagc channel assembly 92 is installed.

To also rigidify the pressed-metal drainage channel 12 and/or to interconnect adjacent drainage channels 12, the stiff strut member 70, again preferably being a length of Rebar RTM or other kind of rigid metal rod, can be slidably inserted in the second support openings 64 of the engagement element 18, and locked in place using the respective second locking devices 68.

The grating 50 is releasably seatable on the interior platfoim surfaces 88 of the drainage channel 12. To releasably secure the grating 50 in place, the channel grating support 176 is utilised. Similarly to the drainage channel support 10, the bridge member 114 is separated. and the female and male member parts 122, 124 are slid through respective opposing wall openings 90, typically being between ihe drainage channel supports 10. The female and male member parts 122, 124 arc inserted through the opposing side walls 80 until their bridge stops 142 abut the exterior surfaces 94 of the side walls 80, and until the female member part 122 contacts the female-body stop 136 ol the male member part 124. Once positioned, the grating 50 is seated on the drainage channel 12 and the grating engagement member 178 is inserted through the grating aperture 196 and into the aligned apertures 138 of the female and male member parts 122, 124 to releasably engage the two-part bridge member 114 with the drainage channel 12.

For longer runs of drainage channel 12, one or more intermediate drainage channel supports 10 may also be utilised in addition to one or more drainage channel grating supports 176.

Additionally or alternatively, the grating 50 may be, preferably releasably, connected to and supported by the bridge member 14; 114 of the or each drainage channel support 10 via a supplementary grating engagement member 98. which in this case may also form the locking element 40 of its two-part bridge member 14.

With reference to Figure 9. a second embodiment of a trench drainage channel support 210 is shown which is specifically adapted for use with the, preferably linear, pressed-metal drainage channel 12 embeddable in a ground trench T. Parts which are similar or identical to the first embodiment have similar references with 200' added.

Further detailed description is omitted.

The trench drainage channel support 210 is modular, comprising a bridge member 214. a support element 216 at each end of the bridge member 214, and an engagement element 218 to which a ground support member 20 is engagable.

The bridge member 214 in this case is one-piece. being preferably formed from cast metal, but may be two parts as described with reference to the first embodiment, or indeed more than two parts if required.

Each support element 216 is releasably engagable with an apertured projecting arm 21 4a of the bridge member 214. A body 21 6a of the support element 216 is sfid onto the apertured projecting arm 214a. The engagement element 218 is formed as part of the support element 216, and provides the first support opening 254 and preferably the second support opening 264. similarly to those described with reference to the first embodiment. As above, the first and second locking devices 258, 268 extend into their respective first and second support openings 254. 264. and again are preferably tool-less rdeasahle screw-threaded fasteners with manually gripable heads br tightening and releasing.

With the bridge member 214 slid through opposing side walls 80 of the drainage channel 12, just below the lip 84. the support elements 216 are slid onto the apertured projecting arms 2l4a, and respective ground support members 20 are slid generally vertically into the first support openings 254. The first locking devices 258 secure the ground support members 20 at their requisite heights to impart a fall to the drainage channel 12.

As with the first embodiment, to interconnect adjacent drainage channels 12 and/or to improve torsional rigidity, generally horiiontal stiff strut members 70 are inserted into the second support openings 264 and secured by second locking devices 268.

A grating can then he applied, as described above.

It is thus possible to provide a thin-walled pressed-metal drainage channel which is thus much lighter and consequently easier to manoeuvre and transport. By flaring the opposing side walls, the drainage channels can be nested or stacked, again improving storage and transportation. Due to the reduced weight, much longer lengths of drainage channel can he formed and thus installed at any one time. It is also possible to improve the rigidity of the thin-walled drainage channel by utilising the trench drainage channel support. Additional rigidity can be provided by the trench drainage channel grating support. Both of these supports, by engaging through the opposing thin side walls of the channel, prevent or limit splaying. Furthermore, the drainage channel support enables height adjustable support of the drainage channel to allow a predetermined fall to be iip' -ted as required. Yet still further, the drainage channel support enables improved torsional rigidity to he imparted to the thin-walled drainage channel by the inclusion of reinforcement elements extending longitudinally of the drainage channel between drainage channel supports. The present invention thus prevents or limits lateral tilting or tipping of the drainage channel by the drainage channel support being engaged through the side walls adjacent to an upper edge.

However, by being spaced from the upper edge, the ground supports still terminate below any ground surface layer. preventing obstruction or fouling.

The words comprises/comprising' and the words having/including' when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, hut does not preclude the presence of addition of one or more other features, integers, steps, components or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments. may also be provided in combination in a single embodiment. Conversely, various features of this invention which are, for brevity, described in the context of a single embodiment. may also be provided separately or in any suitable sub-combination.

The embodiments described above are provided by way of examples only, and various other modifications will he apparent to persons skfllcd in the field without departed from the scope of the invention as herein descr bed.

Claims

Claims I. A trench drainage channel support comprising a two-part bridge member for insertion through opposing side walls of a trench drainage dianne] hdow a grating. a support element extending from each bridge member part. and an engaging element for engaging a ground support member.
2. A trench drainage channel support as claimed in claim 1. wherein the two-part bridge member includes an elongate female member part and an dongate male member part slidably receivable in the female member part.
3. A trench drainage channel support as claimed in claim 2. wherein the male member part includes a female member stop at or adjacent to a proximal end, so as to increase an engagement length between the female and male member parts.
4. A trench drainage channel support as claimed in claim 2 or claim 3. wherein the female and male member parts each include an alignable aperture for receiving a locking element to prevent or inhibit linear separation.
5. A trench drainage channel support as daimed in daim 4. further comprising a locking element for interengaging the alignable apertures.
6. A trench drainage channel support as claimed in claim 5, wherein the locking element is a headed elongate screw-threaded fastener.
7. A trench drainage channel support as claimed in any one of claims 4 to 6.wherein at least one of the alignable apertures has at least in part a screw-threaded bore.
8. A trench drainage channel support as daimed in any one of the preceding claims, further comprising a bridge stop at both ends of the two-part bridge member, the in use bridge stop abutting exterior surfaces of the trench drainage channel side walls to prevent or limit outward flexion.
9. A trench drainage channel support as claimed in claim 8, wherein each stop is a laterally outwardly projecting liange.
10. A trench drainage channel support as daimed in claim 5, wherein each flange extends continuously around a lateral perimeter of each bridge-member part.
11. A trench drainage channel support as daimed in any one of the preceding claims, wherein each support element is a depending arm which extends below the two-part bridge member to space away the engaging elements.
12. A trench drainage channel support as claimed in any one of the preceding claims, wherein the engaging element includes a support opening for receiving an elongate ground support member.
13. A trench drainage channel support as claimed in claim 12. wherein the support opening is a through-aperture in which a ground support member is slidably receivable.
14. A trench drainage channel support as claimed in claim 12 ordaim 13, wherein the engaging dement lurther includes a locking device for retaining a ground support member in position when engaged with the opening.
15. A trench drainage channel support as claimed in claim 14, wherein the locking device is a tool-less releasable screw-threaded fastener which is screw-threadingly receivable in a body of the engaging element so as to project into the opening.
16. A trench drainage channel support as claimed in any one of claims 12 to 15, wherein the engaging element further includes a second opening which extends transversely to the first said opening for receiving a stiff strut member which interengages two spaced apart trench drainage channel supports.
17. A trench drainage channel support as claimed in claim 16. wherein the engaging element also includes a second locking device for retaining the stiff strut member in position when engaged with the second opening.
18. A trench drainage channel support as claimed in claim 17, wherein the second locking device is a tool-less releasable screw-threaded fastener which is screw-threadingly receivable in a body of the engaging elcmcnt so as to project into the second opening.
19. A trench drainage channd support as claimed in claim 18. wherein longitudinal axes of the first and second locking devices intersect or overlap for simplified manual operation.
20. A modular trench drainage channel support comprising a bridge member for insertion through opposing side walls of a trench drainage channel below a grating, a support element slidably receivable on each end of the bridge member, and an engaging element on each support element for engaging a ground support member.
21. A trench drainage channel support substantially as hereinbefore described with reference to Figures 1, 2, 7 and 8, or Figure 9 of the accompanying drawings.
22. A trench drainage channel grating support comprising a two-part bridge member for insertion through opposing side walls of a trench drainage channel below a grating. and a grating engagement member for engaging a grating with the at least one of the parts of the bridge member.
23. A trench drainage channel grating support as claimed in claim 22, wherein the two-part bridge member includes an ethngate female member part and an elongate male member part slidaffly receivable in the fema'e member part.
24. A trench drainage channel grating support as claimed in claim 22 or claim 23, wherein the male member part includes a female member stop at or adjacent to a proximal end, so as to increase an engagement length between the female and male member parts.
25. A trench drainage channel grating support as claimed in claim 23 or claim 24, wherein the female and male member parts each include an alignable aperture for receiving the grating engagement member to prevent or inhibit linear separation.
26. A trench drainage channd grating support as claimed in claim 25, wherein at least one of the alignable apertures has at east in part a screw-threaded bore.
27. A trench drainage channd grating support as claimed in any one of claims 22 to 25 wherein the grating engagement member is a headed elongate screw-threaded fastener.
28. A trench drainage channel grating support as claimed in any one of claims 22 to 27, further comprising a bridge stop at both ends of the two-part bridge member, the in use bridge stop abutting exterior surfaces of the trench drainage channel side walls to prevent or limit outward flexion.
29. A trench drainage channel grating support as claimed in claim 28, wherein each stop is a laterally outwardly projecting flange.
30. A trench drainage channel grating support as claimed in claim 29, wherein each flange extends continuously around a lateral perimeter of each bridge-member part.
3 1. A trench drainage channel grating support substantially as hereinhe!ère described with reference to Figures 3, 4. 7 and 8 of the accompanying drawings.
32. A pressed-metal trench drainage channel comprising opposing side walls and a base which is contiguous with the side walls, the side walls tapering in a converging direction towards the base to enable nested stacking for storage and/or transportation.
33. A pressed-metal trench drainage channel as claimed in claim 32, wherein each side wall includes a lip at or adjacent to its upper free edge for supporting a removable grating.
34. A pressed-metal trench drainage channel substantially as hereinbefore descnbed with reference to Figures 5 to 8 or Figure 9 of the accompanying drawings.
35. A trench drainage channel assembly comprising a pressed-metal trench drainage channel as claimed in claims 32 and 33. and two or more spaced-apart trench drainage channel supports as claimed in any one of claims I to 21 received through opposing side walls of the pressed-metal trench drainage channel.
36. A trench drainage channel assembly as claimed in claim 34, further comprising at least one trench drainage channel grating support as claimed in any one of claims 21 to 30 received through opposing side walls of the pressed-metal trench drainage channel.
37. A trench drainage channel assembly as claimed in claim 34 or claim 35.further comprising a grating supportable by the trench drainage channel supports and/or the trench drainage channel grating support.
38. A trench drainage channel assembly as claimed in any one of claims 34 to 36, further comprising a plurality of elongate ground support members engaged with respective engaging elements of the trench drainage channel supports.
39. A trench drainage channel assembly as claimed in any one of claims. 34 to 37, further comprising a plurality of stiff strut members engaged with respective engaging elements for stiffening the pressed-metal trench drainage channel.
40. A trench drainage channel assemily substantially as hereinhefore described with reference to Figures 7 and 8 or Figure 9 of the accompanying drawings.
41. A method of rigidifying a pressed-metal trench drainage channel comprising the step of: a] interengaging opposing side walls of the pressed-metal trench drainage channel by inserting a trench drainage channel support as claimed in any one of claims 1 to 21 through the said side walls.
42. A method as claimed in claim 41, further comprising the step of interengaging spaced apart said trench drainage channel supports with outlying stiff strut members to increase longitudinal and lateral trench drainage channel stiffness and/or to interconnect adjacent drainage channels.
43. A method of installing a trench drainage channel assembly as claimed in any one of claims 35 to 40. the method comprising the steps of: a] inserting first and second trench drainage channel supports through opposing side walls of a pressed-metal trench drainage channel; and b] using ground support members engaged with the engaging elements of the trench drainage channel supports to set longitudinal Md/or lateral orientations of the trench drainage channel.