EP2449178A2

EP2449178A2 - Road construction enabling the cleaning of a road surface and corresponding method.

Info

Publication number: EP2449178A2
Application number: EP10745446A
Authority: EP
Inventors: Mike Rijnbeek
Original assignee: Aannemingsbedrijf Van Gelder BV
Current assignee: Aannemingsbedrijf Van Gelder BV
Priority date: 2009-06-30
Filing date: 2010-06-24
Publication date: 2012-05-09
Also published as: WO2011019271A2; WO2011019271A3; NL2003109C2

Abstract

The present invention relates to a road construction for enabling an open road surface structure to be cleaned, comprising: - an open road surface structure suitable for the passage of a liquid, - a liquid discharge assembly for discharging the liquid from the open road surface structure, and - a liquid supply assembly for supplying liquid in the open road surface structure, wherein the open road surface structure can effectively function as transport layer for the liquid from the liquid supply assembly in the direction of the liquid discharge assembly. The present invention also comprises a method for cleaning a road surface. The present invention further comprises an asphalt composition.

Description

ROAD CONSTRUCTION AND METHOD FOR CLEANING

A ROAD SURFACE

The present invention relates to a road construc- tion for providing a road connection which can be cleaned. The present invention also relates to a method for cleaning a road surface. The present invention also relates to an asphalt composition suitable for application in the road construction and the method.

A large quantity of fine dust is released in road traffic. This fine dust occurs for a multitude of reasons. A large part of the fine dust is released through resistance of tyres to the road surface, for instance when the car accelerates and brakes and when changing gear. Much of this fine dust is therefore released due to the effect of friction. This fine dust causes problems in society in the sense that the air present above and in the vicinity of busy roads is contaminated in excess of a level deemed acceptable. This slows down further development of roads or other projects in the vicinity of such roads.

In order to help obviate this problem the present invention provides a road construction for providing a road connection which can be cleaned, comprising:

- an open road surface structure suitable for the passage of a liquid,

- a liquid discharge assembly for discharging the liquid from the open road surface structure, and

- a liquid supply assembly for supplying liquid in the open road surface structure, wherein the open road surface structure can effectively function as transport layer for the liquid from the liquid supply assembly in the direction of the liquid discharge assembly. An advantage of such a road construction according to the present invention is that the fine dust can be captured and discharged by means of the liquid. The present invention is based inter alia on the insight of the inven- tor that, when the fine dust particles are created, the fine dust particles are electrically charged, after which they move swirling freely through the air. When they come into contact with the ground the fine dust particles generally lose the charge, after which they are blown about again due to the air displacement caused by traffic. It is for instance possible here for the liquid discharge assembly and the liquid supply assembly to be embodied as one assembly which alternately fulfills the function of supply and discharge.

When the road surface of the road surface construction according to the present invention is wet, the same road traffic which causes the fine dust due to the turbulence of the air extracts moisture from the road surface in the form of a vapour or fine droplets, which will fall back onto the road surface under the influence of gravitational force, or will at least be subject to greater gravitational forces than fine dust. The moisture is also very suitable for capturing the fine dust. It is therefore very advantageous that the fine dust is bound to the road surface by means of the moisture. It is further possible that the fine dust is already bound to the road surface when it first comes to rest, or when it is created.

In a first preferred embodiment according to the present invention the liquid supply assembly is arranged, as seen in the longitudinal direction of the road construction, on a side of the open road surface structure for supply of the liquid to the open road surface struc- ture from this one side, and the liquid discharge assembly is arranged on the other side of the open road surface structure relative to the liquid supply assembly. The advantage of these preferred embodiments is that a liquid flow can be realized from one side to the opposite side, by means of which liquid flow a discharge of the captured fine dust can likewise be brought about.

In a further preferred embodiment the liquid supply assembly comprises at least one liquid supply chamber or liquid supply channel provided with a liquid inlet and arranged adjacently of the open road surface structure and in liquid-communicating connection therewith. A liquid supply for supplying liquid to the road surface is hereby provided in advantageous manner. The liquid supply assem- bly is more preferably arranged higher than the liquid discharge assembly.

At least the liquid-communicating connection from the liquid supply assembly to the road surface structure is more preferably situated higher than the liquid- communicating connection from the road surface structure to the liquid discharge assembly, and in this way an incline can be formed of preferably 0 to 10%, more preferably 1 to 8%, more preferably 1.5 to 7%, more preferably 2 to 6%, more preferably 2 to 5%, and more preferably 2 to 3%. It hereby becomes possible to bring about a continuous liquid flow from the inlet to the outlet.

In a further preferred embodiment the liquid- communicating connection from the liquid supply assembly to the open road surface structure and/or the liquid- communicating connection from the open road surface structure to the liquid discharge assembly is arranged under at least a part of the open road surface structure. It hereby becomes possible to distribute the supply and discharge of the liquid over the surface of the road surface.

In order to save relatively expensive drinking water the device preferably also comprises supply means for supplying liquid from a greywater storage. It hereby becomes possible to apply water present in the vicinity in a system and method according to the present invention.

In a further preferred embodiment the road construction comprises cleaning supply means for adding or introducing cleaning agent and/or surfactants to the liquid. The discharge of the fine dust can be further enhanced by using such agents or active substances. Other contamination can also be removed regularly or incidentally from the road surface in this manner. Such substances can also help in capturing the fine dust.

The liquid discharge assembly is preferably integrated into a road surface boundary such as a kerb or a verge, and it is preferably coupled to a sewer. The liquid supply assembly is more preferably integrated into a road surface boundary such as a kerb or verge. With these preferred embodiments a system according to the present invention can be embodied in a manner which is relatively recognizable to the road user. It is of course possible here to apply external features which make it apparent to the user that he/she is making use of a cleanable road.

In a further preferred embodiment the liquid supply assembly and/or the liquid discharge assembly comprises drainage pipes, preferably arranged below or immediately adjacently of the road surface. Such pipes are particu- larly suitable for discharging moisture in environments with fine particles, such as in sand or clay layers.

Drainage pipes are more preferably comprised which are arranged in supply gutters and/or discharge gutters. The drainage pipes can be protected by means of such gutters .

In order to provide an advantageous distribution of the supply water the road construction preferably com- prises supply pipes with a liquid passage restriction.

A further aspect of the present invention relates to a method for cleaning an open road surface structure of a road construction, comprising steps for:

- carrying a liquid into the open road surface structure by means of a liquid supply assembly,

- discharging the liquid.

Such a method provides similar advantages as described with reference to preferred embodiments of the road construction.

The method more preferably comprises steps for controlling the water supply on the basis of measurements of the presence of dust and fine dust particles present on the road surface structure, in the road surface structure, present in the air layer above the road surface structure and/or in the vicinity of the road construction. A predetermined liquid level can hereby be realized and preferably maintained. A level can hereby be set which is optimal for capturing the fine dust at the lowest possible liquid level .

The method is preferably performed during predetermined time periods.

In a further preferred embodiment the method comprises steps for raising the liquid level at adjustable times to slightly below or slightly above the road surface level and subsequently draining the liquid. Using such a method it for instance becomes possible to bring fine dust present in or on the road surface into contact with the liquid and to then discharge it immediately. Such a method can be exceptionally advantageous in relatively long dry periods .

A further aspect of the present invention relates to an asphalt composition for application in a road sur- face structure of a road construction according to one or more of the foregoing claims 1-13, wherein at least a part of the chippings of the asphalt composition has a grain size of 4-30 mm, preferably 4-20 mm, more preferably 4-15 mm, more preferably 6-13 mm, more preferably 8-11 mm, more preferably 4-8 mm, more preferably 11-16 mm, more preferably 2-6 mm. Tests have shown that such an asphalt composition has advantages within the application of the present invention.

Such an asphalt composition preferably comprises reinforcing binders such as bitumen, roof bitumen, polymers, modified polymers. Particularly the polymers and the modified polymers can be advantageously manufactured specifically for providing a very strong open asphalt composition.

For the purpose of discharging the fine dust through the asphalt, this latter preferably comprises an amount of hollow space in a percentage of 10-45%, preferably 15-40%, more preferably 20-30%, more preferably 23- 28%, more preferably 15-25%, more preferably 15-20%, more preferably 20-25% and more preferably about 25%.

A further aspect of the present invention relates to a road construction according to the present invention in combination with an asphalt composition according to the present invention for performing a method according to the present invention.

Further advantages, features and details of the present invention will be described in greater detail hereinbelow on the basis of one or more preferred embodiments and with reference to the accompanying figures.

Fig. 1 shows a schematic cross-sectional view of a first preferred embodiment according to the present inven- tion.

Fig. 2 shows a schematic perspective view of a further preferred embodiment according to the present invention.

Fig. 3 shows a schematic perspective view and a schematic cross-sectional view of a further preferred embodiment according to the present invention.

Fig. 4 shows a schematic perspective view and a schematic cross-sectional view of a further preferred embodiment according to the present invention.

Fig. 5 shows a schematic perspective view and a schematic cross-sectional view of a further preferred embodiment according to the present invention.

Fig. 6 shows a schematic cross-sectional view of a detail of the preferred embodiment of Fig. 5.

Fig. 7 shows a schematic perspective view and a schematic cross-sectional view of a further preferred embodiment according to the present invention.

Fig. 8 shows a schematic perspective view and a schematic cross-sectional view of a further preferred em- bodiment according to the present invention.

Fig. 9 shows a schematic cross-sectional view of three further preferred embodiments according to the present invention.

A first preferred embodiment (Fig. 1) according to the present invention relates to a water supply assembly 1. This is arranged on a foundation 9 having thereon a first sub-grade 8, an intermediate layer of stone asphalt concrete (STAC) 7 and a layer of open asphalt concrete 5. In the claims the asphalt composition is understood to mean the layer of open asphalt concrete. The road is bounded by a kerb 11 and a pavement 14.

The layer of open asphalt concrete 5 is construct- ed from coarse-grained chippings with binders and optionally a quantity of concrete. The binders comprise the stated bitumen and polymers.

According to the present invention this open asphalt concrete is suitable for allowing water to flow therethrough or allowing water to flow therein. It is the intention that the water absorbs and optionally discharges the fine dust. The water can come into contact with the fine dust in, on or above asphalt layer 5.

A water supply pipe 2 is shown on the left-hand side of the figure. This pipe serves to add water for use in a method according to the present invention. Extending from pipe 2 are transverse connecting pipes 3 (shown schematically here) for transporting water from pipe 2 to gutter 4. Gutter 4 serves to distribute the water in the lon- gitudinal direction of the road surface. The gutter is provided with a grate 12 on its top side. On the right- hand side the gutter is provided with openings 6 for transporting water from the gutter to road surface layer 5.

Fig. 2 shows a water discharge assembly 21 adjacently of a road surface with a STAC layer 7 and a road surface layer 5. A discharge gutter 24 is arranged along the road surface. This discharge gutter 24 is covered by means of a discharge-enabling kerb 26, where they together form a series of discharge cavities. On its underside the discharge-enabling kerb 26 comprises a series of hollow spaces for admitting water into the gutter. As can be seen, these discharge cavities have a liquid-communicating connection with the open asphalt layer 5. The kerb is well supported on the gutter between the cavities. Water which has absorbed fine dust according to the invention during the presence in open asphalt layer 5 can be discharged by gutter 24 by means of the liquid-communicating connection.

Fig. 3 shows a water supply assembly. Also shown here is a water supply pipe 2 with feed connections 3 to gutter 31. This gutter is placed such that the open side is directed toward the open asphalt 5. The open asphalt is here also situated on a STAC layer 7. A cover plate 35 provided with openings 36 is situated between the gutter and the open asphalt layer. A distributor pipe with an outlet restriction in the form of small openings 34 is arranged in the gutter. The small openings ensure that the water can only exit the pipe at a low flow rate per running metre of pipe. The water is hereby distributed along the length of the gutter so that it can enter the open asphalt over a great length.

Fig. 4 shows a variant wherein the water is sup- plied to the open asphalt from the underside. A supply pipe 2 with a feed pipe also exists herein. Further provided is a drain or gutter 46 covered by means of a cover or series of covers 47. A control unit 41 is arranged in drain 46 for controlling the water supply in the direction of the road surface. The water supply is performed by means of a transverse pipe 42 which debouches into a passage opening 44 with a cover plate 44. Cover plate 44 is provided with openings 45 for passage of the water in the direction of open asphalt layer 5.

The operation of control unit 41 can be both mechanical and electronic, the latter having the advantage that a whole series of control units 41 can be operated in simple manner. Cover plate 45 also forms a foundation for the open asphalt layer.

Fig. 5 shows a variant of the embodiment of Fig.

4. In Fig. 5 passage opening 53 is arranged in open as- phalt layer 5. The passage opening is provided here with openings 55 in the cylindrical outer surface. The upper side of the passage opening is provided with a closed cover plate. This is situated in the surface of the road. This embodiment thus provides for a lateral outflow of wa- ter from passage opening 53.

Fig. 6 shows the passage opening of Fig. 5 in detail.

Fig. 7 shows a variant of the water discharge assembly. This is a gutter 71 arranged with its open side directed toward the open asphalt layer 5. A cover plate 72 with openings 73 is provided here. This cover plate prevents the migration of asphalt into the gutter.

Fig. 8 shows a further variant of the water discharge assembly. Gutter 81 is arranged here such that the opening to the top makes contact with open asphalt layer

5. The gutter is covered by means of a cover plate 82 provided with water passage openings. The cover plate also provides a foundation for asphalt layer 5. The gutters of these embodiments debouch into a passage (not shown) in the direction of a sewer.

Fig. 9 shows further variants of the water discharge assembly. Fig. 9A shows a variant with a so-called gully 98, wherein the water can flow away above the asphalt in longitudinal direction of the road surface with- out having the resistance which is present when the water has to flow through the asphalt.

Fig. 9B shows a variant with a gutter 91 having a drainage pipe 94 arranged therein. Such a drainage pipe has a hollow space having a filter material therearound for the purpose of preventing passage of coarse particles such as sand while allowing passage of fine dust. On the top side a gutter is provided with openings 93 for admit- ting the water from asphalt layer 5. For this purpose kerb 95 is provided with walls 96, 97 comprising passage openings .

In the variant of Fig. 9C the gully is combined with the gutter.

In addition to a discharge in the direction of the sewer it is also possible that a water treatment device is realized in a supply device for the purpose of providing purification of the water discharged in the direction of the public sewer.

The present invention is described in the foregoing on the basis of several preferred embodiments. Different aspects of different embodiments are deemed described in combination with each other, wherein all combinations which can be made by a skilled person on the basis of this document must be included. These preferred embodiments are not limitative for the scope of protection of this document. The rights sought are defined in the appended claims .

Claims

1. Road construction for providing a road connection which can be cleaned, comprising:

- an open road surface structure suitable for the passage of a liquid,

- a liquid supply assembly for supplying liquid in the open road surface structure, wherein the open road surface structure can effectively function as transport layer for the liquid from the liquid supply assembly in the direction of the liquid discharge assembly.

2. Road construction as claimed in claim 1, wherein the liquid supply assembly is arranged, as seen in the longitudinal direction of the road construction, on a side of the open road surface structure for supply of the liquid to the open road surface structure from this one side, and the liquid discharge assembly is arranged on the other side of the open road surface structure relative to the liquid supply assembly.

3. Road construction as claimed in claim 1 or 2, wherein the liquid supply assembly comprises at least one liquid supply chamber or liquid supply channel provided with a liquid inlet and arranged adjacently of the open road surface structure and in liquid-communicating connection therewith.

4. Road construction as claimed in claim 1, 2 or 3, wherein the liquid supply assembly is arranged higher than the liquid discharge assembly, and in this way an in- cline can be formed of preferably 0 to 10%, more preferably 1 to 8%, more preferably 1.5 to 7%, more preferably 2 to 6%, more preferably 2 to 5%, and more preferably 2 to 3%.

5. Road construction as claimed in claim 4, wherein at least the liquid-communicating connection from the liquid supply assembly to the road surface structure is situated higher than the liquid-communicating connection from the road surface structure to the liquid discharge assembly.

6. Road construction as claimed in one or more of the foregoing claims, wherein the liquid-communicating connection from the liquid supply assembly to the open road surface structure and/or the liquid-communicating connection from the open road surface structure to the liquid discharge assembly is arranged under at least a part of the open road surface structure.

7. Road construction as claimed in one or more of the foregoing claims, comprising supply means for supplying liquid from a greywater storage.

8. Road construction as claimed in one or more of the foregoing claims, comprising cleaning supply means for adding or introducing cleaning agent and/or surfactants to the liquid.

9. Road construction as claimed in one or more of the foregoing claims, wherein the liquid discharge assembly is integrated into a road surface boundary such as a kerb or a verge, and is preferably coupled to a sewer.

10. Road construction as claimed in one or more of the foregoing claims_/ wherein the liquid supply assembly is integrated into a road surface boundary such as a kerb or verge.

11. Road construction as claimed in one or more of the foregoing claims, wherein the liquid supply assembly and/or the liquid discharge assembly comprises drainage pipes, preferably arranged below or immediately adjacently of the road surface.

12. Road construction as claimed in one or more of the foregoing claims, comprising drainage pipes in supply gutters and/or discharge gutters.

13. Road construction as claimed in one or more of the foregoing claims, comprising supply pipes and/or discharge pipes with a liquid passage restriction.

14. Method for cleaning an open road surface structure of a road construction, comprising steps for:

- discharging the liquid.

15. Method as claimed in claim 14, comprising further steps for controlling the water supply on the basis of measurements of the presence of dust and fine dust par- tides present on the road surface structure, in the road surface structure, present in the air layer above the road surface structure and/or in the vicinity of the road construction.

16. Method as claimed in claim 14 or 15, comprising steps for applying the cleaning steps during predetermined time periods.

17. Method as claimed in claim 14, 15 or 16, comprising steps for holding the liquid at a predetermined liquid level in the road surface structure, preferably by means of measuring the height and adapting the supply thereto.

18. Method as claimed in one or more of the claims 14-17, comprising steps for raising the liquid level at adjustable times to slightly below or slightly above the road surface level and subsequently draining the liquid.

19. Asphalt composition for application in a road surface structure of a road construction as claimed in one or more of the foregoing claims 1-13, wherein at least a part of the filling of the asphalt composition comprises a grain size of 4-30 mm, preferably 4-20 mm, more preferably 4-15 mm, more preferably 6-13 mm, more preferably 8-11 mm, more preferably 4-8 mm, more preferably 11-16 mm, more preferably 2-6 mm.

20. Asphalt composition as claimed in claim 19, comprising reinforcing binders such as bitumen, roof bitumen, polymers, modified polymers.

21. Asphalt composition as claimed in claim 19 or 20, comprising empty space in a percentage of 10-45%, preferably 15-40%, more preferably 20-30%, more preferably 23-28%, more preferably 15-25%, more preferably 15-20%, more preferably 20-25% and more preferably about 251.

22. Road construction as claimed in one or more of the claims 1-13, comprising an asphalt composition according to one or more of the claims 19-21.