EP1520943A2

EP1520943A2 - Surface drainage system

Info

Publication number: EP1520943A2
Application number: EP04255633A
Authority: EP
Inventors: designation of the inventor has not yet been filed The
Original assignee: Aco Technologies PLC
Current assignee: Aco Technologies PLC
Priority date: 2003-10-03
Filing date: 2004-09-16
Publication date: 2005-04-06
Also published as: GB2406601B; GB0323197D0; EP1520943A3; GB2406601A

Abstract

An apparatus for a surface drainage system comprises a longitudinal restrictor member 9 and at least one mounting means 10 adapted to locate the restrictor member 9 adjacent a longitudinal drainage slot 5 of a drainage channel section. The mounting means 10 are adapted to enable movement of the restrictor member 9 relative to the slot 5 in order to vary the effective area of the slot opening.

Description

Field of the Invention

The present invention relates to a surface drainage system and specifically, but not exclusively, to wide channel linear drainage systems for surface drainage.

Background

There is an increasing demand for economic, efficient drainage systems for draining surface water (or other fluids) from large catchment areas. Examples include car parks, highways, airport pavements and distribution centres.
One known form of surface drainage system relies on a number of discreet, spaced inlets in the surface to be drained, which communicate with a common, underlying channel. Examples of such systems can be seen in published UK Patent Applications GB-A-2316428 and GB-A-1456021. A commercial system of this general type has also been sold by Marshalls Mono Ltd under the registered trade mark PORCUPIPE.
These drainage systems result in a reasonably robust installation, as the overlying slab of surface material is substantially continuous, only broken by the discreet, spaced inlets. However, the very nature of these systems, with their discreet, spaced inlets, limits the hydraulic efficiency of the system; the inlet area of the system is limited and, particularly in e.g. storm systems, water may be carried over the surface between the inlets.
Another known form of drainage system employs a substantially continuous linear slot in the drained surface to serve as the inlet. It is recognised that surface drainage systems employing linear slots are more efficient than those drainage arrangements possessing discrete inlets, as in general they provide a greater inlet area and minimise the volume of water (or other liquid) that can wash over the drained surface without being entrained by the inlet. US Patent US6000881 shows a linear drainage system of this type, as does GB-A-2311549. Both of the systems described in these documents employ a large underground channel which has at its upper side a narrower throat portion defined by two walls extending upwardly to the surface to be drained, where they terminate to form a continuous slot drain in the surface.
Typically drainage systems will be embedded in concrete or the like under the surface to be drained. For some applications it is often desirable for the open end of the inlet section to be placed at the base of a trench. A top surface of the trench may be constructed such that it forms a part of the surface to be drained. The trench may be formed by shaping wet concrete into a desired shape, such as a U-shape for example. As the wet concrete is laid to form the trench it is laid over the open end of the slot drain before being shaped, e.g. by slip forming, into a U-shape such that the inlet will be at or near the base of the trench. Obviously it is necessary to prevent the passage of wet concrete into the slot drain whilst the concrete is shaped and sets. One means of achieving this is to apply a cover to the slot drain which is removed and discarded after the wet concrete is applied and shaped, but before the concrete fully sets.

Summary of the Invention

In a first aspect, the present invention provides apparatus for a surface drainage system comprising a longitudinal restrictor member and at least one mounting means adapted to locate the restrictor member adjacent a longitudinal drainage slot, said mounting means being adapted to enable movement of the restrictor member relative to the slot in order to vary the effective area of the slot opening.
In a second aspect, the present invention provides a surface drainage system comprising a longitudinal inlet section having one end open (e.g. a slot) to receive drainage liquid and the other end in communication with a drainage void, the system further comprising a restrictor member located adjacent to the open end of the inlet section and adapted for movement relative thereto in order to vary the effective area of the slot opening.
The drainage void can be provided in the form of a pipe portion having any suitable cross-section. A circular or ovoid cross-section is preferred. Alternatively, the void may simply be formed from an open space in the ground or surface in which the drainage system of the present invention is to be provided.
The longitudinal inlet section may be located at an upper portion of the drainage void. The inlet section can be formed integrally with the drainage void. Alternatively the inlet section could be formed independently and attached to the drainage void by any suitable means.
The restrictor member of the present invention can be employed advantageously during the installation of the drainage system in the surface to be drained. The restrictor member may be positioned relative to the open end of the inlet section so as to deflect the passage of wet concrete away from the inlet and/or the drainage void whilst the concrete is shaped and set. The restrictor member can be moved away from the inlet section as the concrete begins to set and the danger of wet concrete entering the inlet and/or the drainage void has been averted.
In a preferred embodiment of the present invention, the restrictor member is configured such that it is capable of sealing the open end of the inlet section and prohibit the entrance of liquids. This feature is advantageous where a concrete trench is provided above the inlet section as the passage of wet concrete into the open end of the inlet section can be guarded against by the closing of the restrictor member against the inlet section to form a seal. It is also advantageous that a seal can be formed when a trench needs to be cleaned and/or debris needs to be removed. The restrictor member can be closed against the inlet section which permits easier cleaning of the trench and/or the removal of debris and, once complete, the restrictor member can be moved away from the inlet section to permit the passage of liquids to the drainage void once more.
The restrictor member is preferably provided with a longitudinal body and can be continuous along the length of the longitudinal inlet section.
The restrictor member may be provided with any suitable cross section, but is preferably provided with a cross section which is capable of forming a seal when the member is brought into contact with the open end of the inlet section. The restrictor member may for example be provided with a cross section that corresponds to the cross section of the open end of the inlet section in order to best provide this seal.
Preferably the restrictor member has a cross section which allows the member to substantially fill the inlet section, thus forming a seal. This feature of the restrictor member is advantageous as it may be used to reinforce the inlet section during installation. As the concrete or the like surrounds the inlet section during installation of the system, the concrete applies lateral forces on the outer walls of the inlet section which act to close or minimise the width of the slot. When the restrictor member is made from a sufficiently robust material(s) it can fill the slot of the inlet section to provide support to the inner walls in resisting the lateral forces which are applied to the outer walls. As the concrete sets the restrictor member can be moved away from the inlet section since the lateral forces applied by the concrete will no longer act to minimise or close the slot.
The restrictor member may be adapted for movement in a vertical plane relative to the open end of the inlet section. Preferably this movement is such that the restrictor member remains parallel to the open end of the inlet section along its entire length.
The movement of the restrictor member may be such that it can be located in any spaced relation relative to the open end of the inlet section, this would allow a user to vary the effective area of the slot opening precisely. Alternatively, this movement may be limited to a defined number of locations such as two locations, one being open and open being closed. The defined locations may consist of three or more defined locations.
Numerous mechanisms and/or fixings may be employed to facilitate the movement of the restrictor member relative to the open end of the inlet section depending upon which plane movement of the restrictor member is desired. Preferably however, a mechanism is provided with at least one mounting means. The mounting means may take the form of an insert capable of extending from the interior of the inlet section. Preferably the insert has a threaded section which allows the movement of the restrictor member by a simple screwing operation. To facilitate a screwing operation, the insert may pass through the restrictor member and culminating in a raised screw head or the like protruding from the member's upper surface.
The insert may be secured in the interior of the inlet section by its base being secured to a structural bridge which extends laterally across the inlet section. Alternatively, or additionally, the insert can be secured against an interior wall of the inlet section.

Brief Description of the Drawing

The invention is described below, by way of example, with reference to the accompanying drawing in which:
Figure 1 illustrates a perspective view of a surface drainage system of the present invention in a closed position;
Figure 2 illustrates a cross section of the system of Figure 1;
Figure 3 illustrates a perspective view of a surface drainage system of the present invention in an open position;
Figure 4 illustrates a cross section of the system of Figure 3; and
Figure 5 illustrates a cross section of a surface drainage system of the present invention in an open position and embedded in surface to be drained.

Description of an Embodiment

Figures 1 to 4 show a surface drainage system in accordance with an embodiment of the present invention.
The system consists of an inlet section 1 having two side walls 2, 2', both of which are flanged at its top edge to form outwardly tapered lips 3, 3'. The walls 2, 2' are spaced laterally from one another and joined by tubular cross-members 4. These tubular elements also form openings that extend through the inlet section from one lateral side to the other.
At their upper end, the spaced walls define a longitudinal slot 5 designed, in use, to collect water from a surface in which the system is installed.
The lower ends of the walls are spaced further from one another than the upper ends, so that the channel they define flares downwardly. This helps to prevent any solid material that enters through the slot becoming wedged in this channel.
The spaces within the defined between the walls 2, 2' and the tubular cross-members 4 serve as conduits through which liquid that drains into the slot can pass through and out of the inlet section's lower end.
The side walls 2, 2' are also flanged at their bottom edges to form outwardly extending lips 6, 6'. The lips 6, 6' are used to secure the inlet section to a pipe 7. The pipe 7 is of a suitably large cross section to provide large capacity liquid drainage. The pipe has a longitudinal opening or openings along its top edge which the lips 6, 6' can be secured either side of. In this arrangement liquid will drain into the slot, through the conduits in the inlet section and out the inlet section's lower end into the pipe.
Each of the side walls also has a series of side inlet openings 8 spaced along their length, between the tubular cross-members. These allow water to drain into the channel defined by the walls from either side of the inlet former.
Figure 5 illustrates a surface drainage system if the present invention imbedded in a surface material such as concrete. A concrete trench (not shown) may be provided above the drainage. The trench could have a generally U-shaped configuration having outwardly extending portion at the top of each side wall. The outwardly extending portions are formed relative to the surrounding surface to be drained such that any liquid is capable of passing over these portions and down into the trench.
The inlet section of the system can be installed at the base of the trench.
During installation of the system, the tubular cross-members 4 which extend through the inlet section across its width to form a series of passages that extend from one side of the section to the other can accept the surface material, for example concrete, therethrough. When installed, concrete bridges extend through these passages to support the surface material slab over the pipe 7.
A restrictor member 9 can be seen disposed above the open slot 5 of the inlet section. As will be described in more detail below, the restrictor member is capable of movement relative to the slot of the inlet section.
The restrictor member 9 is provided with a lower surface which corresponds in shape to the lips 3, 3'. An insert 10 extends through the restrictor member 9 and through the slot into the interior of the inlet section. The insert has an external thread and a bolt head 11 raised above the upper surface of the restrictor member for easy access. The base of the insert is mounted on a secure attachment point within the inlet section. As illustrated, in this example the base of the insert is secured with a threaded connection into the cross members 4 of the inlet section.
Through the application of a rotational motion applied to the raised bolt head 11 of the insert 9, the restrictor member can be moved vertically towards and away from the slot 5 of the inlet section.
The restrictor member 9 has a cross section which allows the member to substantially fill the slot 5 of the inlet section, thus forming a seal. This allows the restrictor member to reinforce the inlet section during installation. As the concrete or the like surrounds the inlet section during installation of the system, the concrete applies lateral forces on the side walls 2, 2' of the inlet section which act to close or minimise the width of the slot 5. The restrictor member is made from a sufficiently robust material(s) such that it can fill the slot of the inlet section to provide resistance against the lateral forces which are applied to the side walls. As the concrete sets the restrictor member can be moved away from the inlet section since the lateral forces applied by the concrete will no longer act to minimise or close the slot.
The pipe 7, inlet section 1 and restrictor member 9, collectively referred to as a channel section, may be formed from any of a number of appropriate materials including, for example sheet metal (e.g. steel), cast metal (e.g. iron), any other variety of plastics materials or a combination of these materials. Preferably the channel section is moulded from medium density polyethylene (MDPE).
The channel section may be provided in differing cross sectional sizes depending on the capacity required. The channel section is preferably constructed having a mean size of 900mm deep by 600mm wide. A smaller system may be provided with a size of 600mm x 400mm.
The channel section is preferably has a two metre standard length, although it may be convenient to also provide shorter or longer lengths (e.g. 1 metre lengths). However, if the site where the system is to be located has sufficient handling capabilities, longer lengths of channel section may be used.
The channel section may be formed in one piece. By moulding the channel section in one piece, complete with tubular cross-members 4, the component count for a drainage installation is minimised. This approach can also create a stiffer integrated monolithic structure. Alignment problems during installation are also avoided.
However, in this example a fabricated two (or more) part construction is shown. For instance, an upper portion of the channel section that forms the slot inlet may be formed separately from the lower pipe portion.
It is intended that a series of these sections be interconnected to form a high capacity drainage system. Any suitable form of connection between the open end faces of adjacent sections may be employed. Preferably a water seal (not shown) is fitted between end faces of adjacent channel sections to form a seal. This seal may be made of rubber, neoprene or ethylene propylene diene monomer (EPDM) which is highly resistant to water. The seal is preferably a donut section with a hollow centre to allow give good compressibility to absorb tolerance variations on length.
A drainage system employing the channel sections described above can be installed in the following manner. First a trench is dug in the ground of the area to be drained. Multiple channel sections are laid into the trench, butted one against the other and secured together. The channel sections are held in position in the trench (e.g. using straps) and then embedded in concrete (or other surfacing material). The channel sections serve as a liner in use. The load is borne by a reinforced top slab incorporated during installation of the system, including the concrete bridges that extend through the channel sections.
Typically the concrete will be poured in at least two stages to avoid excessive up-thrust due to the buoyancy of the channel produced by the wet concrete during the first pour.
To increase the robustness of the concrete slab and bridges, reinforcement may be positioned around the channel and loose bars passed through the lateral passages prior to the concrete being poured.
To prevent ingress of wet concrete into the inlet section 1 and pipe 7 during installation the restrictor member 9 can be moved such that it forms a seal with the slot 5 defined by the inlet section. After the wet concrete has been laid over the slot and a trench shaped, the restrictor member can be moved out of sealing engagement with the slot before the concrete sets fully but not before the concrete has set sufficiently to prevent ingress into the inlet section or pipe.
When the restrictor member 9 is screwed down tight against the tapered lips 3, 3', it seals the inlet of the channel section. The forming of a seal between the restrictor member and the inlet section may also be useful when a trench needs to be cleaned and/or debris needs to be removed. The seal permits easier cleaning of the trench and/or the removal of debris and, once complete, the restrictor member can be moved away from the inlet section to permit the passage of liquids to the pipe once more.
Where the system is intended to be used in a car park with asphalt or block pavior wearing courses, a heel guard grating structure may be mounted on the opening of the trench, flush with the surface to be drained.
Other fittings or gratings may also be mounted on the opening of the trench, flush with the surface to be drained.

Claims

An apparatus for a surface drainage system comprising a longitudinal restrictor member and at least one mounting means adapted to locate the restrictor member adjacent a longitudinal drainage slot of a drainage channel section, said mounting means being adapted to enable movement of the restrictor member relative to the slot in order to vary the effective area of the slot opening.
An apparatus as claimed in Claim 1, wherein the restrictor member is configured such that it is capable of sealing the drainage slot.
An apparatus as claimed in Claim 1 or 2, wherein the restrictor member has a longitudinal body.
An apparatus as claimed in any one of the preceding claims, wherein the cross-section of the restrictor member corresponds to that of the drainage slot.
An apparatus as claimed in any one of the preceding claims, wherein the restrictor member is adapted to be moved vertically relative to the slot.
An apparatus as claimed in any one of the preceding claims, wherein the restrictor member is adapted to remain parallel to the slot when it is moved relative to the slot.
An apparatus as claimed in any one of the preceding claims, wherein movement of the restrictor member is adapted to be facilitated by a screw.
An apparatus substantially as described herein with reference to any one of the embodiments shown in the accompanying drawings.
A drainage channel section comprising the apparatus claimed in any one of the preceding claims, a longitudinal drainage slot having one end open for receiving drainage liquid and another end in communication with a drainage void.
A drainage channel section as claimed in Claim 9, wherein the drainage void is a pipe portion.
A drainage channel section as claimed in Claim 9 or 10, wherein the slot is arranged, in use, in the upper region of the drainage void.
A drainage channel section as claimed in any one of Claims 9 to 11, wherein the slot is formed integrally with the drainage void.
A drainage channel section as claimed in any one of Claims 9 to 11, wherein the slot is formed separately from the drainage void.
A drainage channel section as claimed in any one of Claims 9 to 13, wherein the channel section is made of medium density polyethylene.
A drainage channel section substantially as herein described with reference to any one of the embodiments shown in the accompanying drawings.
A channel system comprising at least two drainage channel sections as claimed in any one of Claims 9 to 15.
A channel system as claimed in Claim 16, wherein a seal is arranged between the drainage channel sections.
A channel system as claimed in Claim 17, wherein the seal is made of rubber, neoprene or ethylene propylene diene monomer.
A channel system as claimed in Claim 17 or 18, wherein the seal is donut-shaped.
A channel system substantially as described herein with reference to any one of the embodiments shown in the accompanying drawings.
A surface drainage system comprising a longitudinal inlet section having one end open to receive drainage liquid and the other end in communication with a drainage void, the system further comprising a restrictor member located adjacent to the open end of the inlet section and adapted for movement relative thereto in order to vary the effective area of the slot opening.