Edible barcodes, DARPA’s modified crops, insects, Pivit Bio raises $70M, rice straw ethanol, renewable concrete, automated indoor farming, biobased hairstyling, silkworms making spider silk: The Digest’s Top 10 Innovations for the week of October 17th

#6 New concretes found, now reinforced with renewable materials

In Germany, researchers will present a prototype of a natural fiber-reinforced concrete bridge at the BAU 2019 trade fair in Munich on January 14 to 19, 2019.
Textile-reinforced concrete (TRC) is durable, formable in diverse shapes and suitable for lightweight construction. As the name suggests, conventional TRC is reinforced with carbon or glass-fiber fabrics rather than steel. A research team at the Fraunhofer Institute for Wood Research, Wilhelm-Klauditz-Institut WKI is now replacing these fabrics with eco-friendly natural fibers. These alternatives rival conventional concrete’s performance, but leave a smaller carbon footprint, and cost less to make.

The secret to this high-performance concrete is that it is reinforced with carbon, glass or polymer fibers rather than steel. Researchers at the Fraunhofer WKI in Braunschweig want to replace these fibers with a textile based on renewable raw materials, a move that would pay big dividends for the environment and climate. They are going with local products, in this case flax, which may be spun or woven. The researchers can add strands of polymer fiber to the flax to create a hybrid fabric tailored to the given component’s requirements.

The scientists at Fraunhofer WKI’s Application Center for Wood Fiber Research HOFZET use a double-rapier loom with a Jacquard attachment to weave this material mix. With this weaving machine – the only one of its kind in Europe – experts are able to produce innovative lightweight composite materials with complex, application-specific textile structures and integrated functions. The machine combines conventional and sustainable materials in a way that is both cost efficient and technically sophisticated. They are then embedded in high-performance concrete with the structural density that protects the fibers almost completely against weathering. This weave is also modified with natural resins.