FR2727701A1 - Surface for horse racing tracks or athletics tracks - Google Patents

Abstract

The track is composed of natural or artificial rocks. It is composed of one material from a group of soft rocks, a volcanic material and one or more materials from a group of hard rocks. It also includes a very small quantity of a hydroscopic material (1-5 per cent by volume).The soft materials group includes artificial rocks such as clinker and shale. The volcanic material is pozzolana. The group of hard materials includes quartzite, granite, basalt, but the most used hard materials are porphyry and hard limestone. The proportions are 10-80 of the soft material, 10-80 pozzolana and 2-15 of the hard material. For horse racing tracks the diameter of the materials is between 0-30 mm, for athletics tracks the materials are between 0-10 mm.

Description

The present invention is in the field of civil engineering and it relates to a composition of materials for the coating of sports tracks, racetracks in particular
We know the use of natural volcanic rock pozzolan) alone in a thin layer (2 to 3 cm) as a wearing course; above a thicker base layer stabilized with a bitumen emulsion; a drawback of this process lies in the impermeability of the coating thus formed; rainwater forms puddles which can only be absorbed by evaporation, which can sometimes lead to prolonged unavailability of the runway.

 We also know the use of clinker (artificial rock) in a greater thickness (8 to 10 cm); such a coating has the disadvantage of being dark in color (dark gray or black) and of being dusty which on the one hand gives the track an impression of dirtiness and on the other hand gives rise to a poor reflection of the light, which during the night races generates, so that the brightness is sufficient, a significant expenditure of energy.

 The object of the present invention is to propose a composition of natural and / or artificial rocks, which provides a track, such as an athletics or horse-riding track, with both constant adequate flexibility, good permeability and therefore good rainwater drainage, adequate brightness and durability unmatched with previous coatings.

The mother idea of the invention consists in associating three materials, namely:
a) at least one of the so-called soft materials of the group comprising clinker and shale,
b) pozzolan (volcanic material),
c) at least one of the so-called hard materials of the group comprising porphyry, quartzite, riolite, granite and basalt. We can also consider hard limestone as a suitable "hard" material, in regions where the aforementioned eruptive or crystalline materials are lacking.

 The incorporation of pozzolan inhibits, or at least considerably slows down, the hardening of shale and / or clinker (hardening which would not fail to occur if these materials were used alone); in addition the incorporation of pozzolan improves permeability by forming a drain system.

 The incorporation of "hard" material prevents too rapid spraying of the pozzolan and soft material.

The invention recommends the ranges of the following proportions, in% of the volume
a) "soft" material: 10 - 80
b) pozzolan: 10 - 80
c) "hard" material: 2 - 15
Still according to the invention, it is proposed to add in very small proportion (1 to 5% -) a hygroscopic agent such as metacrylate.

The particle size (mm of the mesh of the sieve) of the materials, both "soft" and "hard", as of the pozzolan, can advantageously be included in the ranges of following proportions, depending on the destination - for the tracks of horse racing (racetracks, merry-go-rounds): O - 30 (optimum: 15 mm); -for athletics tracks
(running tracks, sports grounds): O - 10 (optimal: 5 t)
The following examples of compositions are given by way of non-limiting indication
- for horse racing tracks a good example of proportions is as follows
a) red clinker: 75%
b) pozzolan: 15%
c) red porphyry: 8%
d) metacrylate: 2%
- for athletics tracks a good example of proportions is as follows
a) red clinker 85%
b) pozzolan: 11%
c) red porphyry,
(grain size: 5 mm) 2%
d) metacrylate: 2%
Finally, it should be noted that the invention is obviously not limited to these examples, but that it extends to all combinations of materials, as defined above.

Claims (2)

1.- Composition based on natural or artificial rocks,  intended for the constitution of tracks such as horse racing  and athletics or other sports fields, characterized:  in that it includes  a) at least one of the materials  said to be "tender" from the group comprising clinker and  shale,  b) pozzolan (flight material  canonical),  c) at least one of the materials  said to be "hard" from the group comprising porphyry, a quarter  zite, riolite, granite, basalt and limestone  hard; 2.- Composition according to claim 1, characterized  in that it further includes a  hygroscopic agent in very small proportion (1 - 5% in  volume); 3.- Composition according to claim 1, characterized  in that said hard material is  more particularly porphyry;  4.- Composition according to claim I, characterized  in that said hard material is  more particularly hard limestone; 5.- Composition according to claim 1, characterized  in that the pro forks  portions of the materials are as follows  a) soft material ":: 10 - 80  b) pozzolan: 10 - 80  c) "hard" material: 2 - 15 6.- Composition according to claim 1, characterized  in that for hip tracks  track, (racetracks, merry-go-rounds), the grain size of the mate  rials is included, in the range: 0 - 30 mm; 7.- Composition according to claim 1, characterized  in that for tracks  athletics (running tracks, playgrounds),  the particle size of the materials is included in the  range: 0 - 10 mm.