Big C with a small environmental impact
Art and culture enthusiasts can look forward to a diverse program under the motto ‘C the Unseen’ with around 150 projects and more than 1000 events – and to taking a breather in the Big C.
This year, the European Capital of Culture Chemnitz 2025, together with 38 municipalities from the region, is presenting itself as a lively and surprising place in eastern Germany, in the heart of Europe. Art and culture enthusiasts can look forward to a diverse program under the motto ‘C the Unseen’ with around 150 projects and more than 1000 events – and to taking a breather in the Big C.
The street furniture for relaxing was developed in the laboratory of the Lightweight Construction in Civil Engineering research area at the Chair of Lightweight Structures/Plastics Processing at Chemnitz University of Technology (TUC). The prototype is to be followed by 20 series products distributed throughout the city. Its name, Big C, refers to its design as the letter C.
Innovative and sustainable processes and materials were used to create the arch-shaped designer item: concrete for the main body with a reinforcement made from a carbon warp knitted fabric with weft insertion.
The textile reinforcement enables savings in concrete, slim shapes and maximum force absorption, as the reinforcing fibres are absolutely stretched in the warp knitted structure. The RS MSUS-G/HG warp knitting machine with weft insertion and its innovative successor, the Wefttronic II G, from Karl Mayer are predestined for its production.
Dr Jürgen Tröltzsch, Special Specification Project Manager, Karl Mayer’s Technical Textiles Business Unit
“We are delighted to be able to contribute to the Chemnitz 2025 Capital of Culture program with our technology. Big C once again stands for the versatile application possibilities of our warp knitting machines with weft insertion,” comments Dr Jürgen Tröltzsch, Special Specification Project Manager at Karl Mayer’s Technical Textiles Business Unit.
Relax with a clear environmental conscience
The concrete base of the Big C was manufactured using a 3D concrete printing process
Unlike concrete reinforcements, textile reinforcement structures do not corrode and therefore do not require the usual concrete cover with a thickness of 2.5 to 5 cm. This enables a filigree design and saves up to 80 per cent concrete – a building material that is considered one of the most important climate killers, Karl Mayer explains.
High-strength fine concrete with CO2-reduced cement and a suitable formwork system for casting the concrete were also developed to ensure an impressive environmental balance. The ‘C the unseen’ lettering could thus be integrated into the concrete body during casting. A newly developed 100 per cent recyclable corrugated cardboard formwork was also used for the first time for the cost-effective production of the curved special component.
The concrete base of the Big C was manufactured using a 3D concrete printing process. To improve seating comfort, the seating surfaces in the lower curve of the approximately 1.80 metre high Big C can be covered with ergonomically shaped wooden slats.2
Flexible, fast and easy to maintain – the Wefttronic II G
The textile mesh structure can be ideally adapted to the reinforcement requirements in carbon concrete
With the Wefttronic II G, Karl Mayer offers a profitable and versatile production machine. The all-rounder produces between 350 m and 400 m of textile per hour at a speed of 1,600 rpm, depending on the stitch density and material used. Thanks to the high variability of the machine in terms of yarn density in the filler yarn and weft yarn areas, the textile mesh structure can be ideally adapted to the reinforcement requirements in carbon concrete. The Wefttronic II G is just as flexible when it comes to yarn. The common technical fibres glass, carbon and polyester can be processed. The resulting open grid articles have widths of 4.6 m to 6.2 m.
In addition to being efficient, the innovative warp knitting machine with weft insertion is low-maintenance, durable and extremely easy to operate. Variants are available in gauges of E 6, E 10 and E 18. The equipment features include a solution for stabilising the selvedges, monitoring the weft yarn tension and a central suction device.
