According to Kirnbauer, the goal must be to develop good concrete recipes and to use the right concrete at the right place. He is referring here to alternative, non-rusting reinforcement materials such as, for instance, textiles based on glass fibres or basalt fibres, currently very much on the rise. With these materials not as much cover is required as with steel - a good approach to saving material, as the thickness of the protective layer can be reduced. Another possibility lies in the construction, making greater use of skeleton frame structures to save concrete. "For me the main premise is using building materials in such a way that, as far as possible, one exploits only their strengths. Here it would be important to consider deconstructability at the planning stage. When today we conceive a building that, at the current level of technology, can be deconstructed as simply as possible and the materials used can be sorted according to type, then surely, we are on the safe side." The real potential of the concrete of the future lies in the 5 "Cs": saving on energy-intensive "clinker" and replacing it by granulated blastfurnace slag from the steel industry, fly ash from coal-fired power plants, or silica dust from the semi-conductor industry, the further development of "cement" that leads to a better "concrete", the "construction" as an intelligent design process and, finally, "carbonisation", i.e. the absorption of CO_2. Further promising approaches to replacing clinker are the use of magnesium silicate, which is even CO_2 negative, but is resource intensive, or calcined clays that can be "annealed" to save energy. This development is currently being tested with LC3 (Limestone Calcined Clay Cement] initiative by a research team in Lausanne.
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