Today at the Brno University of Technology, the last elements of the parkour playground dedicated by Stavební spořitelna of Česká spořitelna (Buřinka) to the City District of Prague 11 were printed on a frame 3D printer. 12.5 t of a special concrete mixture from Master Builders Solutions CZ was needed for the printing, which took place in the Laboratory of Construction 3D Printing at the AdMaS Centre of the Faculty of Civil Engineering and lasted 10 hours of clean time. The printed obstacles are poured with recycled rebetong concrete for reinforcement. As another step to support innovation, Buřinka became one of the founding members of the Association of Innovative Technologies and 3D Printing in Construction.

42 % of Czech people know 3D concrete printing

Czech people are also familiar with the use of 3D printing in construction thanks to the 3D printed house Prvok. 42 % of respondents know the possibilities of 3D concrete printing. Every tenth can imagine metal printing. Thirty percent of people have not yet heard about the possibilities of using 3D printing in construction. That is why Buřinka is coming up with another project to support this technology. "After Prvok, we wanted to bring 3D concrete printing even closer to the public to show the possibilities of its use. There are several interesting aspects in the parkour playground – sustainability and uniqueness of 3D printing, active leisure and accessibility for the general public," Libor Vošický, the Chairman of the Board of Buřinka, says.

Did you know that 3D printing can be used in construction? Yes, it is possible to print from concrete (e.g. houses) – 42 % Yes, but so far only plastic can be printed – 27 % Yes, it is possible to print from metal (e.g. bridges) – 10 % I don't know – 30 %

Frame printer at BUT

All 14 elements of the course were printed on a spin-off frame printer by the 3Deposition company, which was founded by the experts from the Faculty of Mechanical Engineering at the Brno University of Technology. "The printer applies 50 mm wide layers of special concrete mix at a speed of 155 mm/s and can print objects up to 3x3x3 m. It can be disassembled, taken to another location and reassembled," Petr Krejčiřík, the head of the development at 3Deposition, says, who participated in the development of the printer for the team from BUT.

"The playground with a circular floor plan has a diameter of 14 m and contains 14 3D printed elements, which are connected by steel pipes. To increase the strength, the individual walls are poured with recycled concrete and reinforced with shaped steel reinforcement. They are then anchored to the concrete foundations at a non-freezing depth," the 3Deposition founder David Škaroupka, who professionally led the entire process of creating the playground, says.

The second generation of composite compound for 3D printing

The second generation of a special MasterFlow 3D mixture is used for element printing, which contains cement, aggregates, water, polypropylene fibers and special additives. "Complex and often conflicting requirements were placed on the development of the mixture. The mixture must be easy to pump, but at the same time it must not run off and must solidify quickly. We managed to achieve this thanks to additives such as stabilizers, setting accelerators and plasticizers," Michal Zámečník from Master Builders Solutions CZ says.

Recycled concrete uses construction waste and saves natural resources

24 m3 of recycled concrete from Skanska was used for the foundations of the parkour playground and the filling of individual elements. The so-called Rebetong is environmentally friendly, its production produces up to 15 % less CO2 than ordinary concrete. Instead of natural aggregates, it contains recycled brick chips, so it uses construction waste. It makes up almost half of the volume of waste in the Czech Republic and only 15 % of it is further used. "After the demolition of the house, the construction debris is assessed on site and the material intended for further processing is stripped of large pieces of wood, metals, plastics, etc. Such coarsely sorted material is crushed and ready for further use, which is the essence of circular economy," Pavel Zelinka, the main technologist from Skanska, says.

The Association of Innovative Technologies and 3D Printing in Construction was established

After the successful implementation of Prvoka Buřinka, the development of 3D printing technology is also supported. Therefore, on June 24, 2021, together with Master Builders Solutions CZ, it became one of the founding members of the Association of Innovative Technologies and 3D Printing in Construction. "The development of 3D printing will be helped by more intensive cooperation between the private and scientific spheres. Therefore, we decided to support the establishment of the association in order to share knowledge from practice and research. This will lead to a shift in the entire industry and accelerate the introduction of 3D printing in practice," Libor Vošický, the Chairman of the Board of Directors of Stavební spořitelna of Česká spořitelna Buřinky, says.

Contacts for Media:

Monika Kopřivová, SSČS communication specialist, 724 087 666, monika.koprivova@burinka.cz

Hana Burečková, account manager of AMI Communication, 604 684 103, hana.bureckova@amic.cz