FI74758C - Procedure for making coating for sports pitches, isynnerh et tennis pitches. - Google Patents

Description

74758

The invention relates to a method for producing a coating for sports fields, in particular tennis courts, in which your method! a brick powder, a mineral material and a tile binder, namely a hydraulically curable thin-10 layer mortar according to MM 18 156, are applied on top of the prefabricated area structure.

German patent application P 31 11 128.9, filed on 20 March 1981, relates to sports grounds, in particular paving for tennis courts and its construction. The surface layer of this coating is formed from an ico-13 bulk material containing mainly brick powder, mineral material and inorganic binder. This curable mass is a dough-like, aqueous slurry containing a tile binder as a binder, namely a hydraulically curable oil layer mortar according to MIN 18 156. According to this method for producing a coating, a dough-like slurry consisting of a tile filler, a brick powder and a mineral material, preferably quartz sand mixed with water, is applied to a prefabricated area structure with a substantially flat surface.

The invention according to said patent application P 31 11 128.9 comes from the inventor of the invention disclosed in this application. The content of said application P 31 11 128.9 thus forms part of the description of this application, insofar as it is necessary for an understanding and further explanation of the present invention.

according to said earlier proposal, the coating ingredients are applied in the form of an aqueous slurry onto the preformed substrate and bind therein. The finished 35-I iettce must have a porridge-like texture and a relatively peony, vo Sipi slip, in order to be Tao after Binding. tiu coating good water permeability. The preparation of a useful slurry presents some difficulties because clumping may occur upon contact of the tile binder with the wet brick powder, and the high viscosity of the resulting slurry requires high forces to achieve an even distribution of all components. When transporting 5 preformed aqueous sludge to a preformed substrate, there is a risk that the pre-leveled substructure surface becomes uneven from wheel arches or the like. After bonding, the aqueous slurry coating has a flat, dense surface comparable to the surface of the bound concrete, which must be roughened mechanically in a special step before the coating is used as a tennis court or the like.

It is an object of the present invention to provide a method for producing a coating for sports fields, in particular tennis courts, which has the advantages of German patent application P 51 11 128.9, but avoids the disadvantages associated with the preparation and application of an aqueous slurry of coating ingredients. In particular, the aim is to facilitate application to the prefabricated substructure 20, to increase the water permeability of the finished coating and / or to avoid mechanical roughening of the surface of the bonded coating.

Since the method for producing a coating for sports fields, in particular tennis courts, in which a brick powder, a mineral material and a tile binder, namely a hydraulically curable thin-layer mortar according to DIN 18 156, is applied to a prefabricated substructure, the solution according to the invention the brick powder, the mineral material and this tile binder are applied to the substructure in the form of a dry-mixed hiulc bag mixture; b) smoothing and compacting the dry particulate mixture; and c) spraying the compacted particle mixture with water to wet the particle mixture layer evenly.

Preferred embodiments of the method according to the invention relate to the selection of a slab binder and a mineral material, the composition of the dry-mixed particle mixture, the components, the order of addition of the road mixture in the preparation of the particulate mixture, the application of the particulate mixture to the surface structure surface and the preferably repeated spraying of the compacted particle mixture -5 Vciat suction s sa is shown.

According to the method of the invention, a coating is thus obtained for sports courts, in particular tennis courts, which have a brick-powdered surface layer mostly on a conventional substructure, for example a substructure 10 with a typical layered pitch of tennis courts according to Olli 18 035 leaf 5; in such a case, the dry-mixed particle mixture is applied over the dynamic layer of such a vessel structure to form a tennis coating.

In addition to the brick powder, the coating must contain hard, preferably rounded, particles of inert material, for example quartz sand particles. Another, very important advantage over conventional brick powder surface layers can be seen in the fact that the method according to the invention provides a "bonded" coating, with a tile binder acting as a special and additional binder. Surprisingly, it has been found that the process according to the invention avoids the formation of a hard floor-mortar or concrete-like surface layer, and instead of a suitable addition of water, the dry-mixed and compacted particle mixture gives a fluffy bound mass after the bonding reaction. Of course, the clay minerals of brick powder also take part in the bonding event caused by the tile binder.

According to the method of the invention, on the other hand, the strength of the brick powder layer can be considerably increased, so that a higher stress resistance is obtained; on the other hand, by a suitable selection of the proportions of the coating components, the value of the sliding property can be adjusted over a wide range, for example as a rest or sliding friction defined on the surface of the coating under a certain load. In particular, despite the increased strength, the sliding property of the brick powder surface layer, which is known as a brace, can be achieved.

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In addition, the sliding property can be adjusted for specific value requirements. Finally, the softness of a given surface layer can affect its softness by selecting certain layer thicknesses.

The method according to the invention gives a surface layer with a very high resistance to stress, so that even after several hours of tennis matches, practically no care and / or maintenance work is required. The surface layer is frost-friendly, so that when used with a skill-resistant substructure, no special renovation work is required even after the winter break.

The coating prepared according to the invention is water-resistant and is permeable to the necessary extent, i.e. after rain excessive amounts of water flow rapidly, i.e. within a few minutes, through the porous surface layer into the area structure and are discharged therefrom. even in a considerable, long-lasting drought, the surface layer particles on the top surface do not come off, so there is no significant dust deposition. Thus, the coating made according to the invention continuously allows for weather-independent playability without additional measures such as known sweeping, rolling and / or wetting. Since the dust deposition has been considerably reduced, the coating prepared according to the invention can also be used as a floor covering in tennis halls and the like.

Finally, the coating according to the invention can be repaired very easily, in which case a dry-mixed mixture of particles is applied to the worn areas and water is carefully sprayed on it. The re-applied mate-30 also binds in very thin layer thicknesses without additional measures, certainly with the former coating material.

The method according to the invention will now be described in detail with reference to the production of a surface layer 45 for tennis courts. Brick powder, tile binder and quartz sand serve as essential components for the preparation of such a surface layer.

As a brick powder, a well-known commercial product is used, which

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, 5 74758 is very widely used for forming a surface layer in known tennis courts. Preferably, a brick powder with a grain size of 0/3 is used, i.e. a material whose average particle size does not substantially exceed 5 3 mm.

Tile binder is also a well-known commercial product, which ämät ti viilci calls hydraulically curable thin-layer mortar (cf. Bill 18 156, parts 1 and 2). Such hydraulically curable thin ply mortars are powdered mixtures of hydraulic binders, mineral aggregates (mostly 0.5 mm grain size) and organic mixtures. Preferably, tile binders are used in the context of the present invention which meet the requirements of DIN 18 156-M (cf. BIN 18 156, Part 2) for thin-15 layer mortar. in contrast to the usual modification of the tile binder, in this case the dry tile binder powder is thoroughly mixed with the other solids, and the resulting mixture is uniformly moistened with water.

The composition of such a tile binder is known. For example, German Patent 1,158,430 discloses the use of a mortar containing 24.8-89.9% by weight of Portland semen, 0.2-6.5% by weight of methylcellulose, having a viscosity of between 10-7000 cP measured at 2% by weight. in aqueous solution, and about 10-75% of aggregates such as sand or ground limestone and mixed with about 10-40> 1 water for use so that the viscosity of the aqueous phase of the mixture rises to at least 500 cP so that tiles and tiles can be installed, covered with a layer of mortar and laa-30 tat is pressed dry here. It and U.S. Patent No. 2.93 * 1.932 exemplify some of the tile binder compositions useful for this purpose. German patent publication 1,646,493 discloses a reinforcing mortar which, in addition to cement and screened sand 35, contains 0.1-1.5% by weight of methylcellulose and 1.0-10% by weight of a mixed polyprolerate with 20-80% by weight of vinyl chloride and 80-20% by weight of vinylproplon. . In addition, this installation mortar may still contain .6 74758 5-25% by weight of wire. In addition, German Offenlegungsschrift No. 2,146,709 discloses a mortar mixture for use in the thin-layer installation of tiles and tiles, containing 25 to 85% by weight of cement, 5 0.05 to 0.15% by weight of methylcellulose having a viscosity of 1000-5000 cP measured in 2% water. in solution, melamine-formaldehyde condensate products containing 1,5 to 6% by weight of sulphonic acid groups, with a viscosity of 40 to 500 cP measured in 20% aqueous solution, 0,02 to 0,1% by weight of water-soluble, non-ionic polyalcrylamide, and in each case dry adapted to the total weight of the mixture, the residue is sand and / or ground limestone. The mortar mixture may additionally contain 0.05-5% by weight of asbestos fibers.

15 With reference to those publications, their content, in so far as it relates to the composition of a tile binder, namely a hydraulically curable thin-layer mortar in accordance with DIN 18 156 (part 1 and part 2), must also be included in that material.

According to these publications, such tile binders consist mainly of about 24.8-89.9% by weight of cement, about 10-75% by weight of aggregates such as sand and / or ground limestone and about 0.2-6.5% by weight of methylcellulose, and may in addition to these 25 optionally contains other components, namely up to 10% by weight of a copolymer of vinyl chloride and vinylpropion, up to 6% by weight of rne-lamin-formaldehyde condensate product, up to 0.1% by weight of polyacrylamide, up to 25% by weight of asbestos. Examples of suitable cements are Portland cement, Portland slag cement, limestone slag cement, iron ore cement, pozzolanic cement and the like. The following configurations have proven to be very suitable for this purpose: li 7 .. 74758 tile binder I. with

48.0% by weight of Portland cement PZ 55 F

45.0% by weight of washed, heat-dried quartz sand, 0.1-0.6 mm 5 4.2 weight-55 dispersion powder polymer on the basis of vinyl chloride / vinyl propion 2.5% by weight of methylcellulose (degree of substitution 30 55 methoxyl; viscosity 10,000 mPas 2- Brookfield, 10 to 20 ° C and 20 rpm) 0.3 wt.% to 5o calcium oxalate plate binder II with

47.0 weight-55 blast furnace slag portland cement HOZ 35 L

48.0 wt. To 5-5 washed, heat-dried quartz sand, 0.2 0.2-0.6 mm 2.5 wt.% Methylhydroxyethylcellulose (degree of substitution 25 $ 5 methoxyl, 10% ethylene glycol ether; viscosity: 20,000 mPas for 2% for an aqueous solution according to Brookfield 20, 20 ° C and 20 lcierr./min) 2.0 wt.% cellulose fibers, diameter: about 30 μm, length: about 300 μm 0.5 wt.% -50 calcium chloride

Quartz sand is usually served by a "rough" grade product used in the construction industry; such quartz sand has an average particle size of up to about 0.7 mm. The term "quartz sand" includes, in addition to finely divided silica, other finely divided, inert minerals, as well as mixtures of silica with such minerals.

If desired, in addition to the essential components mentioned, there may be other admixtures, such as some colorants, fungicides, bactericides or herbicides, and other known admixtures.

The hardness and strength of the surface layer obtained by the method according to the invention, as well as the sliding properties of this surface. the upper surface of the backing layer can be adjusted to a large extent by a suitable selection of the parts of said components.

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Without a minimum proportion of quartz sand, the desired sliding properties cannot be achieved, especially in wet conditions. With the indicated proportions of brick powder and quartz sand, an increase in the tile binder portion leads to an increase in hardness and an increase in the coefficient of friction of 5 rest friction and sliding friction. Such coefficients of friction can be considered as fixed points for sliding elements. To determine these coefficients of friction, a test piece (10 cm long, 5 cm wide, 0.5 cm thick) made of smooth shoe soles and under a load of 150 N is pulled over the test surface at a speed of initially 0 and finally 5 cm / selc. The required traction forces are measured using a power box and the coefficient of friction is determined by the formula: coefficient of friction = traction / load.

The coefficient of friction at rest friction means the force required to move the test piece 15; the coefficient of friction of the sliding friction corresponds to the required force at a speed of 3 cm / sec. Under these conditions, the friction coefficients of friction and sliding friction in the range 2.7-3.0 were determined for known brick powder coatings. By suitable selection of the proportions of the various components, the coefficients of friction in this range can also be achieved in the surface layers prepared according to the invention. With the indicated proportions of brick powder and tile binder, increasing the proportion of quartz sand results in a decrease in these coefficients of friction, which as a result promotes sliding on the upper surface of the surface layer.

In order to produce a surface layer which is particularly suitable as a tennis court cover, 100 volumes of brick powder can be mixed with 10 to 90 volumes of quartz sand and 20 to 60 volumes of tile binder. (Operation with volume 30 orifices has proven to be good in practice, as the effects of the currently highly variable and difficult-to-detect moisture content of brick powder have been largely eliminated here). Preferably, 100 volumes of brick powder are mixed with 20 to 60 volumes of quartz sand and 35 to 55 volumes of tile binder to prepare a dry blended particle mixture. In this case, the composition "tile binder I" or "tile binder

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.9. 74758 ne II ", without this leading to significant differences in surface layer properties.

Due to the high strength of the cover made according to the invention, this can be done with a relatively small layer thickness on the prefabricated substructure. The minimum layer thickness is determined by the design life of the coating. In this respect, the minimum layer thickness of the finished, bonded coating must increase to 10 mm, but at least 5 mm. The maximum layer thickness is apparent from the observation that as the layer thickness of the surface layer increases, its softness increases; the layer thickness cannot therefore exceed 30 mm, in particular not more than 35 mm. Higher layer thicknesses must also take into account cracking and reduced water permeability. Layer thicknesses between 15 and 25 mm have proven to be good, with a layer thickness of 20 mm being very advantageous. In the method according to the invention, the dry-mixed particle mixture is applied in a dry state on a prefabricated substructure, leveled and compacted therein. In compaction, the layer thickness decreases, so a fluffy, dry particle mixture must be applied at a higher layer thickness in order to obtain a coating with the above-mentioned layer thickness after compaction and bonding. In general, the layer thickness of the fluffy, loose particle mixture decreases with tii-25 shrinkage and bonding to about 15-20 (; ό), so to ensure the aforementioned layer thickness of the finished coating, the loose particle mixture must be applied to the prefabricated substructure at a correspondingly higher layer thickness.

For many applications, a satisfactory coating is obtained already when the coating is applied by the method according to the invention on a flat, solid, dry and water-draining foundation. Such a foundation may be a natural intact subsoil or a prefabricated substructure. As a substructure, especially for tennis courts, a layer according to DIN 18 035, sheet 5 with a filter layer, a support layer and a dynamic layer is preferred, in which case the surface layer prepared according to the invention is then used as a tennis coating. In view of DIN 18 035, sheet 5, its contents must also be incorporated into this specification, in so far as this is necessary as a further explanation of the substructure, filtration layer, support layer and dynamic layer, including their materials, grain sizes and requirements. by a method of preparing a coating on a water-permeable, bitumen- or core-bonded substrate, for example on a substrate in the form of a known mass field. If the above-mentioned as-10 asphalt or concrete layer serves as a base, and its water permeability is insufficient, a number of bores can be drilled through this layer up to the water-draining foundation.

On a substantially flat surface of the prefabricated foundation or similar substructure, a dry premixed mixture of said ingredients in dry form is applied. The mixing of the components can take place in conventional equipment, for example rotating drums, which are equipped with internal members which promote thorough mixing. Equipment commonly used for the preparation of concrete, for example, has proven to be good, for example known vehicles for the simultaneous mixing and transport of ready-mixed concrete. Preferably, the brick powder and quartz sand are first placed in a mixing drum or the like, these two components are roughly mixed together by allowing the drum to rotate a few times. A powdered dry tile binder is then added, and evenly distributed among the other components. When adding a tile binder, it is appropriate to avoid a local amount of tile binder. If possible, the tile-30 binder must be introduced into a rotating mixing drum in the above-mentioned mixture of quartz sand and brick powder. After adding the tile binder, mix for at least 5 minutes to ensure even distribution.

The resulting dry blended particle mixture is applied as a pre-planned layer thickness to the surface of the substructure, flattened therein approximately evenly, and then, compacted in a dry state. Sealing can take place with different devices. Hand II has proven to be suitable; .11 74758 towed roller normally used for compacting tennis courts. The compaction does not have to be carried out too far, because otherwise in the subsequent irrigation the moisture will only penetrate insufficiently into the compacted material. Preferably, the rolling is stopped when the layer thickness of the loosely applied and leveled particle mixture has decreased by about 15-20 M.

The still dry, compacted layer of particulate mixture is then sprayed with water. In this spraying, a uniform moisture reception must be achieved through the entire layer thickness of the compacted layer. Appropriate use is made of the finest possible water droplets for this purpose, and a considerable local excess of water is avoided. If too much hydrogen is introduced onto the surface of the compacted layer, the binding reaction takes place relatively quickly, limited to the first areas of the top layer, which prevents moisture from penetrating into the deeper areas. Thus, the homogeneity of the coating over its entire layer thickness can be impaired. Good results were obtained, for example, by spraying the compacted surface with as fine a spray as possible until water remained on the surface of the layer for a short time. This spraying was repeated after a few minutes until the water remained standing on the surface of the bed again, and then repeated once more under these conditions. In practical experiments, about 4-6 liters of water per m 2 of compacted layer about 25 mm thick were applied under these conditions.

After the compacted particle layer has become as evenly wetted as possible, this layer 30 binds over the entire layer thickness within about 12 hours. The playability of the field is then reached in dry weather after about 2-3 days. After bonding the layer, the surface can be sprinkled with a very fine brick powder, if necessary, in order to accelerate the formation of the sliding property typical of conventional brick powder fields.

The coating produced by the method according to the invention can be installed as a coating on a wide variety of sports fields. In particular, this coating is suitable and 12 74758 is intended for tennis courts. Since there is no excessive dust formation when used as a tennis court and the irrigation required by traditional brick powder courts is not necessary, this coating can also be used in sports halls.

5 Other applications include mass fields for other ball games, speed jumps for long jump fields, and running and sprinting tracks.

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Claims (10)

A method for producing a coating for Kent-5 sports facilities, in particular tennis courts, in which a brick powder, a mineral material and a tile binder, namely a hydraulically curable thin-layer mortar in accordance with DIN 18 156, is applied to a prefabricated substructure, characterized in that and applying this tile binder to the substructure in the form of a dry blended particulate mixture; b) smoothing and compacting the dry particulate mixture; and c) spraying the compacted particle mixture with water to wet the particle mixture layer evenly. Method according to Claim 1, characterized in that a hydraulically curable thin-layer mortar is used, in accordance with DIN 18 156, with a tile binder consisting of about 24.8 to 89.9% by weight of cement, about 20 to 75% by weight of aggregates, such as sand and / or powder. limestone, and about 0.2 to 6.5% by weight of methylcellulose, and optionally contains other components, namely up to 10% by weight of a copolymer of vinyl chloride and vinylpropion, up to 25% by weight of melamine-formaldehyde condensate product, up to 0.1% by weight polyacrylamide, up to 25% by weight of trace and / or up to 5% by weight of fibrous material, preferably asbestos. Method according to Claim 1 or 2, characterized in that finely divided quartz sand with an average particle size of 0.01 to 0.7 mm is used as the mineral material. Process according to one of Claims 1 to 3, characterized in that 100 parts by volume of brick powder are mixed dry with 10 to 90 parts by volume of mineral material, preferably quartz sand, and 20 to 60 parts by volume of tile binder in order to prepare the particle mixture. Process according to Claim 4, characterized in that 100 volumes of brick powder are mixed dry with 20 to 60 volumes of mineral material, preferably quartz sand, and 35 to 55 volumes of slab binder to prepare the flux mixture. . Method according to one of Claims 1 to 5, characterized in that the brick powder and the mineral material are first mixed dry in a rotary mixing drum or the like, and then a dry, powdered tile binder is added and, with further mixing, it is evenly distributed in the previously prepared mixture. Method according to one of Claims 1 to 6, characterized in that the dry particle mixture is applied to the surface of the substructure with a layer thickness of 15 to 50 mm. Method according to one of Claims 1 to 7, characterized in that the dry particle mixture layer is compacted by rolling. Method according to one of Claims 1 to 8, characterized in that the compacted particle mixture layer is sprayed with fine water droplets until flowing water is visibly standing on the surface of the particle mixture layer. Method according to Claim 9, characterized in that the spraying with fine water droplets is repeated several times. Il 4 15 74758