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Carbon instead of Steel – Textiles revolutionize the Construction Sector

BERLIN/GERMANY, March 5, 2014 - Ailing Bridges, buildings in need of rehabilitation and aged optics are due to weather and time. Relentlessly, both are gnawing at concrete and steel until they crumble, rust or become unstable. While searching for alternative construction materials for reconstruction and maintenance, more and more attention is drawn towards the textile industry, which, with their materials, has already shaken up the aircraft and automotive industries.

use of carbon-fibre on the roof of the University of Applied Sciences in Schweinfurt

Hair- thin reinforcement: Construction workers put a carbon- fibre fabric in a layer of concrete on the roof of the University of Applied  Sciences (Fachhochschule) in Schweinfurt. | photo: Ulrich van Stipriaan

Technical textiles, especially in glass and fibre composites, have the potential to revolutionize structural, civil and also bridge engineering.  The magic formula is called textile reinforced concrete. The use of fabrics cured in plastic instead of steel for concrete reinforcement, generates non susceptible building material with a promising future. There are still problems to be handled though. The innovation from Germany is (still) expensive due to the lack of suitable test methods and a general building supervisory approval. Therefore textile reinforced concrete cannot (yet) be standardized and is not (yet) profitable, and the application is yet to go further than some reference projects.

But the era of “yet“ and “still“ seems to be ending: The German state has been providing increased financial support for this niche- technology. The outcome of research, building practice and impressive reference projects has not proved this support misguided.
The reconstruction of virtually irreversibly decayed monuments or projects like the reinforcement of the arched roof of the tax office building in Zwickau or the repair of a sugar silo for high- purity food storage in Uelzen are impressible projects indeed.

Dr. Klaus Jensen from the Textile Research Board

With the research of intelligent fibres, FKT- Managing Director Dr. Klaus Jansen is laying the foundation for the application of innovative technical textiles at construction sites. | photo: FKT

“Although Germany's textile research institutes are technologically leading the world, they are facing the problem, that the application potential of innovative technical textiles is hardly known - even in the building sector. The focus of research has been increasingly put on the application of high tech fibres in that sector“, declared Dr. Klaus Jansen, head of the umbrella organization for 16 textile research institutes, the Textile Research Board (FKT). According to Jansen, carbon fibres have the potential to become “the steel of the 21st century“. National conferences with experts from construction and architecture point in the same direction, like Berlin's symposium “Concrete Construction – Visions for the future“ on 26th February. And yet sometimes, the beginning is not only hard but also particularly time- consuming.

non-corrosive and weight optimized textile reinforcement

Overall ecobalance improved: Textile reinforcement is non- corrosive and therefore concrete covers of a few millimetres are sufficient – which reduces total weight and saves transport costs. | photo: V. Fraas Solutions in Textile GmbH

And again: Germany paving the Way

As early as 1992, the Technical University in Dresden prompted a project concerning textile reinforced concrete, funded by the BMWI (Federal Ministry of Economics and Technology), after prepatory work had already been done in the 80's by the predecessor of the present Saxony Textile Research Institute in Chemnitz. This has been followed by two decades of research and development and by model applications of textile- based systems through companies.
Two special research projects of the Textile Concrete Consortium (Tudalit e.V.), funded by the German Research Foundation (DFG) and considered crucial for the industry, were finished in 2011. The subjects of research were “Textile Reinforcement for structural reinforcement and technical maintenance“ (again TU Dresden) and “Textile reinforced concrete – Providing the ground for the development of a new technology“ (RWTH Aachen).

In cooperation with the industry, scientists were able to lay the scientific foundations for the progressive development of the economic use of textile reinforcement. As Prof. Peter Offermann, Chairman of Tudalit and one of the fathers of textile concrete, knows: “Visionary entrepreneurs are crucial   for the breakthrough of textile reinforced concrete.“
Even though Germany again acts as the international pioneer, the economic implementation of textile reinforced systems has been delayed,     similar to large scale projects in the past, which have been publicly sneered at.

The reason for this delay is simple: steel and concrete are standard and are functioning well. So why give up on a material combination, which itself still has remaining potential? One reason to look for alternatives is the longer life span of carbon based textile concrete. Other than the classic combination, it is long term corrosion resistant and therefore not susceptible to penetrating moisture. Extensive reconstruction and maintenance work is no longer required.

carbon-reinforced facade panels at Alphabeton in Switzerland

A look into the future. Carbon- reinforced façade panels at the administrative wing of “Alphabeton” in Büron, Switzerland. | photo: V. Fraas Solutions in Textile GmbH

Individual Approval Procedures or: Destruction first, Construction after

Due to the lack of standardized test methods, textile reinforced concrete is not yet profitable. If there is a plan to build a bridge based on high tech fibre for instance, individual approval is required. This means that the bridge is built completely, then it is loaded with several tons until destroyed.
Afterwards the actual bridge is constructed, based on the results obtained. Facing these procedures, companies are not able to get beyond isolated, expensive reference projects. Nonetheless obstacles have begun to crumble.     

Tudalit's managing director Roy Thyroff can see „clearly recognizable signs“ of an increased application of 2 and 3D textiles in concrete reinforcement. Holding the pioneer role in concrete textiles, Germany must overcome the lack of acceptance and problems with approval and consequently must start to develop suitable, non-destructive test methods.

“We do have legitimate hope of getting the first general building supervisory approval for the application of Tudalit, especially for maintenance and reconstruction, this spring.“ More supervisory approvals could build on that and thus pave the way for a broader range of applications. In other words one could ask: is this the launch of a revolution from the niche?

45 million Euro for Carbon used on Site

The Ministry of education and research (BMBF) seems convinced of the future potential of carbon. Within the framework of the 2013 initiative  “Zwanzig 20 – Partnerschaft für Innovation (a partnership for innovation)” ten consortiums – associations of research institutes and companies in the east of Germany, were funded with 500 million Euro. The consortium „C³ – Carbon, Concrete, Composite“ got €45 million. The 79 associates, that come from different research and economic sectors want to enhance the sustainability, as well as the operational and economic efficiency of construction and maintenance.
“Within the next ten years we want to replace 20 percent of the steel with textile reinforcement and thus we are trying to reach a paradigm shift in the construction sector“,  Prof. Manfred Curbach, leader of the consortium, is setting the goal.

www.textilforschung.de, www.tudalit.de, www.carbon-concrete-composite.de

Ronny Eckert / bi