This invention relates to a lightweight combined kerb drainage element. In particular, the present invention relates to a lightweight combined kerb drainage element formed as a twin-wailed design which is capable of exceeding all current manual handling regulations. By reducing wall sections this allows for increases in flow capacity which enables surface water to drain away more quickly from the road or carriageway.

The use of combined kerb drainage systems has grown in popularity over the past decade, as further legislation pertaining to SuDS (Sustainable Urban Drainage) and numerous other legislative constrains have come into force, also manual handling legislation has grown with such documents from the Health and Safety Executive as the CIS 57 publication.

The weight of both precast concrete and polymer concrete combined kerb drainage systems prove difficult to install, requiring additional machinery and lifting equipment on site to meet with current manual handling legislation, this in turn, creates additional disruption to already overcrowded building sites which requires further health and safety control measures. The use of a lower weight combined kerb and drainage system would allow this system to be installed manually as they have been for generations but in a safer and quicker fashion without the need for additional cumbersome lifting equipment.

Conventional material such as precast concrete and polymer concrete designs are also susceptible to chipping and spalling, requiring on-site remedial works and ongoing maintenance within the product's service life. Both traditional materials require heavily upon the earth's dwindling natural resources, but by using recycled polymers reduces the requirement for such exploitation of natural resources. It is therefore an object of the present invention to provide a combined kerb drainage element which is capable of being manufactured using injection moulding, blow moulding, vacuum forming, rotational moulding, compression moulding, rim moulding, power impression moulding carousel moulding, extrusion or pultrusion moulding or any form of plastics manufacture. The combined kerb drainage element is manufactured from a blend of recycled polymers from both post-industrial and domestic waste streams. A further object of the present invention is to provide a combined kerb drainage element that overcomes the need for a separate gully and pipe drainage system to be installed and, being formed as a twin-walled structure, provides increases in flow capacit which enables surface water to drain away more quickly from the road or carriageway. The twin-walled structure minimises weight and maximises the diameter and capacity of the drainage channel.

Summary of the Invention

According to the present invention mere is provided a combined kerb drainage element comprising an outer wall structure which defines upper and lower surfaces, opposing end surfaces, a rear surface and a front surface adapted to meet a surface to be drained in use, and an inner wall structure which defines Internal load bearing sections and at least one longitudinal drainage channel which communicates with one or more apertures situated in the front surface of the drainage element for allowing water to drain therethrough.

Preferably, the surface to be drained in use is a road, carriageway or other substantially flat surface, such as, for example a car park. In use, the combined kerb drainage element can be manufactured using techniques such as injection moulding, blow moulding, vacuum forming, rotational moulding, compression moulding, rim moulding, power impression moulding or any form of plastics manufacture. The combined kerb drainage element may be manufactured from a blend of recycled polymers from both post-industrial and domestic waste streams. Further preferably, the outer wait structure meets the aesthetic and statutory demands of the kerb. In use, the inner wall structure could be manufactured from a different grade or type of polymer, for example, glass filed polypropylene, to create the additional strength requirements.

In use, the internal load bearing sections defined on the inner wall structure are designed so that they locate with corresponding ribs inside the outer wall structure. Such configuration allows the kerb to be a monolithic load bearing design.

Preferably, the inner and outer wall structures could be connected by a "snap-fit" design or heat staked or could be hotplate, sonic or vibration welded. The opposing end sections define interlocking elements to aid with alignment while being installed and to ensure a watertight seal. In use, the use of hydrophilic seals to facilitate sealing might be required.

Further preferably, in use, the inner and outer wall structures of the combined kerb drainage element define an internal cavity into which a high density poiyurethane foam or similar material can be introduced. In use, other suitable materials including steel, aluminium and composite or synthetic materials may be inserted into the internal cavity, either in addition to the foam or as an alternative thereto, for strengthening purposes.

Also according to the present invention there is provided a method of laying a hollow combined kerb drainage element, comprising the steps of: a) placing a plurality of hollow combined kerb drainage elements along the borders of a surface to be drained;

b) laying the sub-base and subsequently the top coat of the surface to be drained;

c) filling the inner section of the hollow combined kerb drainage elements with a high density poiyurethane foam or similar material. It is believed that a combined kerb drainage element according to the present invention at least addresses the problems outlined above. The advantages of the present invention are that a combined kerb drainage element is provided which is capable of being manufactured using injection moulding, blow moulding, vacuum forming, rotational moulding, compression moulding, rim moulding, power impression moulding or any form of plastics manufacture. Advantageously, although not necessarily, the combined kerb drainage element is manufactured from a blend of recycled polymers from both post-industrial and domestic waste steams. Further advantageously, a combined kerb drainage element is provided that obviates the need for a separate gully and pipe drainage system to be installed and, being formed as a twin-walled structure, provides increases in flow capacity which enables surface water to drain away more quickly from the road or carriageway. Further advantageously, the twin-walled structure minimises weight and maximises the diameter and capacity of the drainage channel.

It is will be obvious to those skilled in the art that variations of the present invention are possible and it is intended that the present invention may be used other than as specifically described herein.

Brief Description of the Drawings

A specific non-limiting embodiment of the invention will be described by way of example and with reference to the accompanying drawings in which:

Fig. 1 shows a side perspective view of a combined kerb drainage element of the present invention having the dimensions of a standard half battered 305mm depth kerb.

Fig. 2 illustrates an expanded view of the kerb shown in Fig. 1. Fig. 3 shows a side perspective view of a combined kerb drainage element of the present invention having the dimensions of a standard half battered 480mm depth kerb.

Fig. 4 illustrates an expanded view of the kerb shown in Fig. 3.

Detailed Description of the Preferred Embodiment

Referring now to the drawings, one implementation of the present invention is illustrated in Fig. 1. Fig. 1 shows a combined kerb drainage element according to the present invention having the dimensions of a standard half battered 305mm depth kerb 10. The kerb 10 comprises an upper face 12 and a lower face 14, and two opposing end sections 16. The kerb 10 also defines a rear face 18 and a front face 20 which is adapted to meet with a surface to be drained in use (not shown) which is most usually a road, carriageway or other substantially flat surface, such as, for example a car park.

The skilled person will appreciate that, when installed, the top surface of the road or carriageway will sit approximately along the line A to A' as indicated in Fig. 1. As can also be seen from Fig. 1, the kerb 10 also includes a high-capacity longitudinal drainage channel 22. The longitudinal channel 22 meets with at least one aperture 24 defined in the front face 20 of the kerb 10. In use, surface water on the road or carriageway is drained through the aperture 24 into the drainage channel 22. The kerb 10 of the present invention therefore serves a number of purposes. It primarily acts as a kerb for structurally retaining the carriageway and also acting as a demarcation between road traffic on the carriageway and pedestrians. Crucially, the use of the present invention overcomes the need for a separate gully and pipe drainage system to be installed. The present invention is installed exactly as more traditional materials, with minimal changes to carriageway laying applications. Fig. 2 shows how the lightweight combined kerb drainage element shown in Fig. 1 oan be manufactured using techniques such as injection moulding, blow moulding, vacuum forming, rotational moulding, compression moulding, rim moulding, power impression moulding or any form of plastics manufacture. The combined kerb drainage element being manufactured from a blend of recycled polymers from both post-industrial and domestic waste streams. It is envisaged that virgin materials may also be used without departing from the scope of the present invention.

The lightweight combined kerb drainage element of the present invention is formed as a twin-walled structure which can be manufactured from up to three sections or components per section, namely first 100, second 200 and third 300 sections of Fig. 2. The first section 100 defines an outer wall structure to meet the aesthetic and statutory demands of the kerb. An internal structure defined by the second 200 and third 300 sections meets the structural demands of the kerb and, more particularly, the D400 loading required of EN/1433. The skilled person will appreciate that the internal structure defined by the second 200 and third 300 sections could be manufactured from a different grade or type of polymer, for example, glass filed polypropylene, to create the additional strength requirements. Ribs 202 defined on the internal structure have been designed so that they locate with corresponding ribs 102 inside the outer structure giving a key strength requirement Such configuration within the internal haunching structure allows the kerb 10 to be a monolithic load bearing design.

In use, the combined kerb drainage element of the present invention could have a "snap-fit" design for the three sections or components, if so required. Alternatively, the kerb 10 could be heat staked or could be hotplate, sonic or vibration welded as part of the manufacturing process. Although not shown in the drawings, the kerbs 10 will include an interlocking element on the opposing end sections 16 to aid with alignment while being installed and to ensure a watertight seal. It is envisaged that the interlocking elements may located on either the outer wall structure or the inner wall structure or indeed both without departing from the general teaching of the present invention.

In addition, the use of hydrophilic seals (not shown) to facilitate sealing might be required.

The skilled person will appreciate that certain components or sections could be manufactured with the use of both injection moulded components and rotational components, or compression moulded or blow moulded parts if so required. Different variations or densities of materials could also be provided. The injection moulded design will permit relevant thin wall structures, and this has been purposely designed to eradicate unnecessary thick wall section requirements with conventional designs, therefore allowing much increased flow dynamics and reduced material use further adding to its environmental benefits. In this manner, the combined kerb drainage element will be totally compliant with the current manual handling legislation within the UK, presently, the system cannot weigh more than 20kg, and furthermore this system will endeavour to comply with MAC compliance.

Whilst a strong load bearing structure can be implemented using the present invention as described so far, it is appreciated that the loading strength characteristics can be further improved if the internal cavity of the kerb 10, which is formed between the twin-walls of the kerb that are provided by the first section 100 and the second section 200, is subsequently pumped with a high density polyurethane foam or similar material, after being installed. The skilled person will appreciate that the present invention can be manufactured and brought to the site and installed in a conventional manner. After installation, the internal cavity of the kerb 10 could then be filled with a further strengthening material through an orifice or opening in the kerb 1 (not shown), which will then cure and provide an incredibly strong structure. The skilled person with appreciate other suitable materials including steel, aluminium, and composite or synthetic materials could be inserted into the internal cavity for strengthening purposes.

Fig. 3 and 4 show a further combined kerb drainage element of the present invention having the dimensions of a standard half battered 480mm depth kerb 10. For such a deep kerb 10 elongate external haunching structures 302 and ribs 304 are required to provide additional strength.

The combined kerb drainage element of the present invention is intended to comply with the Highways Agency (HA) issued Interim Advice Note (IAN) 117/08 or any advice that has preceded this interim advice. This advice note was introduced to help clarify and offer guidance on the Certification required for products manufactured to EN 1433 (Combined Kerb and Linear Drainage Systems) supplied to HA projects.

Various alterations and modifications may be made to the present invention without departing from the scope of the invention.