Innovation: FlyCrete

In the previous BFT issues 06 and 07/2024, the first and second part part of applications for the 2024 Innovation Prize of the Supplier Industry for Concrete Components awarded during the 68th BetonTage was published. This time, the third part follows.

FlyCrete, developed by Çimsa at the Çimsa Cement R&D Center, is a special solution conceived for airports in particular. Due to its ability to achieve a strength of 25 MPa and a load-bearing capacity of 500 tons in just three hours, FlyCrete proves to be an important product. With the aid of FlyCrete, a reopening of airport runways for air traffic is possible within 3 hours.

FlyCrete, which was honored in the innovation category at the Sabanci Golden Collar Awards, is also suited for other industrial floor works because of its quick strength, its durability and its abrasion resistance. In 2023, a project for repairing the runways of the second largest airport in Türkiye was successfully executed, proving the functionality of the innovation. In addition, FlyCrete has already been applied for international patents.

The focus at the Çimsa‘s Sabanci Technology Center (STC) in Munich is laid on the further development of FlyCrete and the expansion of its range of application to various fields. In first experiments conducted at STC with the second generation of FlyCrete, it was possible to achieve a CO₂ reduction of more than 10 % in the production already within one year. This was primarily due to the use of additives and alternative accelerating agents.

Use of CAC

The development of this second generation of FlyCrete is essential to fulfil the requirements on sustainability of the industry.

But what is FlyCrete exactly? The FlyCrete formulation is based on the use of calcium aluminate cement (CAC).  The phase composition of CAC provides a lot of advantages compared with other cements. CAC provides for a high early strength and rapid hardening time. Due to its acid resistance and high abrasion resistance, it offers sustainable solutions for urban infrastructures. It also enables the production of durable products which are even resistant to aggressive environments. The research of these new CAC-based formulations requires much understanding and expert knowledge of the CAC hydration with the addition of special accelerators, plasticizers and hydraulically active fillers.

With the first generation of FlyCrete, a building material was developed – based on CAC and corresponding additives – that achieves a hydration of 17.5 MPa after one hour and 25 MPa after three hours, but nevertheless staying workable for 30 minutes initially. At first, the examinations were conducted under laboratory conditions. A concrete production trial on an industrial scale was then carried out at the Çimsa ready-mixed concrete plant.

The result demonstrates that the hydration of concrete based on CAC with the special additives for this application could be designed to ensure a purposeful setting after the requested time, associated with the rapid development of high early strength.