Classifications

• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C7/00—Coherent pavings made in situ
  • E01C7/08—Coherent pavings made in situ made of road-metal and binders
  • E01C7/35—Toppings or surface dressings; Methods of mixing, impregnating, or spreading them
• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
  • E01C7/00—Coherent pavings made in situ
  • E01C7/08—Coherent pavings made in situ made of road-metal and binders
  • E01C7/085—Aggregate or filler materials therefor; Coloured reflecting or luminescent additives therefor

Definitions

• the present invention relates to road-surfacing material, and more particularly to a road-surface layer, so-called road-dressing, applied to asphalted road constructions.
• a Danish material designated synopal has been admixed with the road-dressing material in an amount corresponding to 8% by weight.
• the present invention relates to a road-surfacing material which will fulfill the desire for light-coloured road Burfaces.
• the present invention thus relates to road surfacing material which is intended to be laid as a road-surface dressing on asphalted roads and which comprises a crushed rock-material, such as quartzite (SiO 2 ), and a binder, such as pitch, and which is characterised in that it further comprises an additive material which will fluoresce when illuminated with ultraviolet light, said additive material having been produced by bringing a mineral substance to a molten state and doping said mineral substance with a doping agent whose presence will cause the mineral concerned to fluoresce, and which has been crushed and/or granulated to particle size which corresponds to the size of the quartzite particles.
• a crushed rock-material such as quartzite (SiO 2 )
• a binder such as pitch
• the inventive road-surfacing material comprises a conventional road Burface-dressing which has admixed therewith an additive material which will fluoresce when illuminated with ultraviolet light, said additive material being mixed with said road-dressing prior to applying the same.
• a very large number of mineral ⁇ which will fluoresce when irradiated with ultraviolet light are known to the art.
• the fluorescent effect of these minerals will vary in accordance with their place of origin, since the chemical composition of the minerals varies from place to place. Consequently, it is difficult, if not impossible, to locate a mineral mining or quarrying site from which the mineral extracted therefrom will have a considerable and fairly uniform fluorescent effect and which can be mined/quarried at reasonable, related costs.
• Typical minerals possessing fluorescent properties are fluorspar (CaF 2 ), limespar (CaCO 3 ), Scheelit (CaWO 4 ), Willemit (Zn 2 (SiO 2 ) and Autunit
• Limespar can be used to great advantage, since when manganese (Mn) is present, limespar will fluoresce with an orange light. Orange is namely a colour rich in contrast.
• the fluorescent additive material is not an untreated mineral, but a mineral which has been treated to provide a fluorescent effect.
• the treatment to which the mineral is subjected in accordance with the invention involves melting a mined or quarried mineral in a furnace of the kind used in the manufacture of mineral wool, i.e. a furnace of the electrosteel type. The molten material is then doped with a doping agent which will cause the mineral to fluoresce, by introducing said doping agent into the molten mineral-bath.
• the melt may then be granulated or cast. Subsequent hereto, the solidified material is crushed to a particle Bize which corresponds to the particle size of the quartzite present in the road-surfacing material, i.e. a particle size of about 10-20 mm.
• the additive material includes one of the minerals limespar or Scheelite doped with manganese or molybdenum respectively.
• the amount in which the mineral shall be added in order to provide a fluorescent effect will depend on the mineral concerned and also on the strength of fluorescence desired.
• the proportions in which the additive material is admixed with the road-surface material are also significant. A larger proportion will naturally result in a greater fluorescent effect.
• the additive material is present in the road-surfacing material in an amount which corresponds to 2-25% by weight, preferably about 10-15% by weight.
• the present invention is not limited to any particular mineral or doping agent. Those minerals which will fluoresce are well known, and the concentrations in which the fluorescent substance is contained in such minerals in order to achieve fluorescence is also known. Consequently, the skilled person is able to acquire this knowledge and is also capable of varying the proportion of the doping agent in the material, and also to vary the proportion in which the invented additive material is present in a road surface, so as to achieve the intended fluorescent effect.
• the present invention thus provides an additive material which, distinct from natural fluorescent materials, will produce a relatively smooth and uniform fluorescent effect.
• a fluorescent road-surface will greatly enhance road safety. It is namely found that a fluorescent road-surface will also provide improved road-vision and improved ability to discern objects on the road, even under daylight conditions.
• the natural light includes a large amount of ultraviolet light, which means that the light conditions of the inventive road-surface will be a considerable improvement on the light conditions afforded by a conventional road-dressing.
• the invention includes the concept of fitting automotive vehicles with lamps which emit a large proportion of ultraviolet light.
• lamps which emit white light together with a significant proportion of ultraviolet light can be used in conventional vehicle headlamps.
• the optical effect thus achieved is highly pronounced .
• the road surface will appear to glow in the dark, and objects present on the road will stand-out against the road surface, thereby enabling the objects to be discerned easily from a long way off.
• a mineral such as limespar for instance
• the resultant road-surface will obtain a wear-resistance which corresponds in all essentials to the wear-resistance of a conventional road surface.
• the invention thus fulfills the aforesaid objects.
• the invention is not limited to any particular additive material, and the choice of a suitable mineral for the purposes intended is therefore left to the person skilled in this art.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Road Paving Structures (AREA)
• Radiation-Therapy Devices (AREA)
• Compositions Of Macromolecular Compounds (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20373135

Family Applications (1)

Country Status (7)

Cited By (5)

Citations (4)

• 1988
  • 1988-08-26 SE SE8802996A patent/SE462109B/sv not_active IP Right Cessation
• 1989
  • 1989-08-25 JP JP1509034A patent/JPH03501040A/ja active Pending
  • 1989-08-25 DE DE89909635T patent/DE68905813T2/de not_active Expired - Fee Related
  • 1989-08-25 WO PCT/SE1989/000447 patent/WO1990002226A1/en active IP Right Grant
  • 1989-08-25 EP EP89909635A patent/EP0426760B1/en not_active Expired - Lifetime
• 1990
  • 1990-04-25 DK DK102090A patent/DK165598C/da not_active IP Right Cessation
  • 1990-04-25 FI FI902084A patent/FI93889C/sv not_active IP Right Cessation

Patent Citations (4)

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