Sport on holiday? While for some this amounts at most to a game of beach tennis or a couple of lengths of the hotel pool, for a growing number of people sport is the focal point of their annual holidays. From skiing to hiking, cycle touring to canoe trips – there are many...
Innovation for sports surfaces
Who hasn't been there – football on a clay pitch – the often dry and dusty hard playing surfaces are seldom popular. Players would prefer a synthetic turf pitch with elastic filler material for better energy absorption, but this kind of pitch is significantly more expensive to purchase and install. Construction of a synthetic turf football pitch with elastic supporting layer and filler material costs around 60 €/m2(375,000 €), a clay pitch only around 26 €/m2 (163,000 €) – a too large difference for many communities and football clubs.
One alternative to a clay or synthetic turf pitch is syntex-ground, a new sports surface made of fine sand, fibre chaff and polypropylene fibres and developed by the German Dold Sportflächen GmbH based in Hardt in the Black Forest region of Germany. The properties of syntex ground were tested by the engineering company and test institute at Münster (MPI) in Berglen-Öschelbronn. The layer construction of the playing surface corresponds to that of a clay pitch where instead of the clay surface layer, a mixture of fine sand and fibre chaff is applied. The fine sand has very rounded edges which reduces clumping of the grains with each other and ensures that the sand layer remains loose and smooth even without continuous maintenance work. Shear strength and loose sand is combined to give a surface with high elasticity.
The MPI test institute examined the new playing surface in detail compared to a clay pitch. "The high elasticity of the syntex®-ground playing surface could be felt without doubt", stated Marko Münster, a publically recognised and certified expert for sport, golf and riding areas. In his expertise he determines that the energy absorption measured in six tests showed an average of 33.1% while energy absorption measurements on a clay surface showed an average value of 15.6%.
The syntax-ground surface was also better with regard to water permeability. The permeability of the sand surface was around 20 times higher than the minimum requirement for clay pitches according to the standard DIN 18035-5 while the water retention capacity was more than 44 M.-% (mass per cent composition). In conclusion, Münster determines in its test report that, "Due to the play and care properties, the syntex-ground surface is a significant improvement compared to conventional clay hard courts and thus, an interesting alternative to synthetic turf playing fields."
So much for (tested) theory, but what do users say? How the playing field survived in practical use was demonstrated by the comprehensive school at Wolfach where the old clay hard court was replaced with a syntax-ground surface 12 months ago.
At first the elastic surface was unusual: "The substrate is softer and better for the joints than the old hard surface," summarises sports teacher Oliver Fritsch the positive reaction. The sports surface is an all-round talent and suitable for use in all weathers. "The pitch doesn't get hard even in summer heat, when it rains it is wet but the water runs off and the surface stays firm," explains Fritsch.
A further major plus is the reduced risk of injury. Even when the game gets a little wild, the sports teacher can remain relaxed: "So far we haven't had any cases of children suffering grazes after falling", says Fritsch.
Everyone at the Wolfach comprehensive school agrees that the sports surface with syntex-ground is a significant improvement and even the town authorities are convinced.
Not only the user satisfaction, but also the price of the pitch makes it attractive. At around 38 €/m2, syntex-ground is more expensive than a clay surface but significantly less expensive than a synthetic turf pitch. Secondary costs for the surface from the Dold Sportflächen GmbH are also low.
Care of syntex-ground surfaces requires little outlay. "From April until October the pitch needs to be dragged with a dragging frame such as a Speed Harrow once or twice a month depending on the intensity of use. This keeps the pitch even and reduces growth of weeds", explains manufacturer Christof Dold.
As syntex-ground is a water-bonded surface, it should be kept in a ground-moist state in order to maintain permanent bonding of the components. In dry weather it is sensible to water the pitch well before it is exposed to heavy use.
The playing surface can even withstand a certain amount of neglect. According to the community authorities at Wolfach, the playing surface at the school was given no maintenance at all for one year due to time schedule difficulties and remained in a playable condition. "Uneven areas and signs of play in the sand nearly completely removed themselves in the rain," explained the head groundsman.
The Dold Sportflächen GmbH is happy with the popularity of the playing surface. The company gathered nearly 25 years' experience in the construction of riding arenas and now makes good use of this knowledge in the construction of the sport surface. Managing Director Christof Dold has concentrated since 2012 on construction of sports facility. The manufacturer sees ideal uses for syntax-ground surfaces in heavily used school, club or training facilities which need to be available all year round but should also be financially available for communities and clubs.
The fall protection values of this playing surface should also be noted. The corresponding suitability test certifies a critical fall height of 1.5 m which makes syntex-ground also suitable as an alternative playground surface. The manufacturer guarantees high quality levels through his choice of selection of quality raw materials and a previously unknown mixing technology which results in a universally homogeneous and consistent material mix – compact, water permeable and long-lasting.
Environmental compatibility of syntex®-ground is also a topic. Clay playing surfaces are often made up of a dynamic base layer using raw materials from mining or heavy industry and which may contain pollutants.
Syntex®-ground is made of a carefully selected quality of sand. Decisive here are grain-size distribution and purity (without silt) as well as an individually determined amount of additives, so-called stabilisers, made of rot-proof synthetic textile chaff and fibres. The fibre chaff, made of non-woven textiles are industrial manufacturing scraps in the same quality as the finished saleable goods. A small amount of fine synthetic fibres added to the mix provide syntax-ground with additional strength and can also be used to regulate the firmness of the surface.
The sports surface not only gains points for environmental compatibility during its manufacture, after removal, all materials can be recycled for use in riding paddocks and arenas. In this way, no new plastics need to be manufactured or disposed of for decades to come – a further advantage for users who need to pay no disposal costs but must only reimburse the cost of transport.
Dold Sportflächen GmbH
78739 Hardt, Germany
Tel.: 0049 7422 7128
Photos + Text: Dold Sportflächen GmbH