Where sports, innovation and public infrastructure come together
Where sports, innovation and public infrastructure come together
Both the Arena Condá and the Allianz Parque stadiums in Brazil now use a synthetic turf surface that has cork granules as infill. Cork was also used for a synthetic turf rugby field that was built in Namibia. While their contribution to the biomechanical and shock-absorbing properties of the field are undisputed, the controlling effect of these granules on the surface temperature makes the difference in warm climate environments.
Football and rugby players all over the world prefer synthetic turf surfaces with an infill over any other type of synthetic turf. The infill is essential to provide them with the required stability by allowing them to plant their studs in the surface, as well as to make sliding comfortable and to experience a reasonable ball roll. As the infill layer keeps the synthetic turf blades in an upright position, the ball roll will remain limited to what the designers of the synthetic turf system had in mind during their design process. Synthetic yarns in an upright position also only bend in the direction they are supposed to bend when pressure is exercised on the surface.
Performance infills come in many shapes and forms, but infills derived from natural materials like cork are becoming increasingly popular. An important reason is that natural infill is a much more sustainable solution than the polymeric infills that were historically used. Lately, recognition of the temperature controlling effects has also been gaining ground. Here, cork has several additional advantages over any other natural infill.
Of all natural materials available to be converted into an infill for a synthetic turf surface, cork has the best characteristics and capabilities to contribute to the cooling of a synthetic turf surface. Cork is a natural cellular material consisting of millions of tiny closed cells. Each cell is filled with air and sealed by a waxy natural substance. As the cells are closed and tightly packed and because air has a very low thermal conductivity, heat transfer by convection inside the
cells is largely suppressed. Also, ambient heat moves through cork much more slowly than through the black rubber crumb or mineral infill as the thermal conductivity of cork is up to four times lower than typical rubber components.
As a result of the reduced heat in the top-layer, moisture trapped in between the various cork granules is not forcibly evaporated. Moisture trapped in between the granules is only released when there is pressure exercised on the surface, like a player running or sliding over the surface. Once released, the moisture acts as a lubricant and coolant, thus contributing to the player-surface experience.
As Brazil is one of the countries that is most susceptible to the change in climate the world is currently experiencing, the cooling properties of cork infill are well received.
Beyond on-field performance, cork also contributes to the environmental profile of the installation. As growing environmental awareness is increasingly demanding thorough life cycle assessments (LCAs) of products and processes, Amorim Cork Solutions asked the Portuguese Institute for Research and Technological Development in Construction, Energy, Environment and Sustainability (Itecons) to assess the LCA of its products. The non-profit organisation concluded that cork infill still captures carbon when used on a synthetic turf surface, and has a negative carbon footprint that ranges from–1.80 to -1.68 kg CO₂ eq. per kilogram of product. Here the density of the granules determine the final outcome.
This data was established in accordance with the Product Environmental Footprint (PEF) method that the industry, through the EMEA Synthetic Turf Council (ESTC) and the European Commission have jointly developed. The data is also according to EN 16449. This result reflects cork’s ability to store carbon during its lifecycle, supporting a reduction in the overall carbon footprint of sports infrastructure projects. Furthermore, cork infill also complies with REACH, meaning that it does not release harmful substances to the environment. Last but not least, some 60% of the cork infill Amorim Cork Solutions provides are cork granules that have been derived from recycling left overs and cut offs from the production processes of other cork products or from cork waste that end users have returned to the company.
Cork infill has a negative carbon footprint that ranges from–1.80 to -1.68 kg CO₂ eq. per kilogram of product
Amorim Cork Solutions
With both the Arena Condá and the Allianz Parque stadiums in use by football clubs that play in the highest football league in Brazil, both stadiums require a synthetic turf surface that is FIFA compliant. These surfaces are thoroughly tested before FIFA approves them for use in professional football venues. The elastic recovery and lightweight structure of cork granules contribute to consistent performance over time, supporting the long-term durability of the field.
With attention to detail during the installation as well as the execution of their maintenance agreements with the respective venues, Amorim Sports partners EngeGlobal and Soccer Grass delivered the finishing touch to these projects.