Utilizing Textiles as Integrated Formwork for Additive Manufacturing with Concrete

Textile reinforced concrete (TRC) and additive manufacturing (AM) with concrete are two highly topical research areas which complement each other. TRC enables the construction of thin-walled, lightweight elements with high mechanical performance, such as shell structures. Additive manufacturing offers the possibility to economically fabricate components and buildings with complex shapes. In the current state of the art, 3D concrete printing of horizontally unsupported elements, such as overhangs or shells, is challenging, and so is the integration of reinforcement. In the work at hand, the authors present a combination of TRC and AM which allows for the production of reinforced shell-like structures using 3D concrete printing methods. The approach is to use a multi-layered textile both as reinforcement and as integrated formwork. By fixing the textile in place on a few supporting points and printing concrete onto the resulting textile shape, shell like structures can be manufactured. The bottom layer of the textile is comparatively close-meshed, so that concrete can be printed onto it as a kind of shuttering. The upper layer of the textile is open-meshed and made of high performance fibers, allowing the printed concrete to penetrate through the textile layer which acts as reinforcement of the complete component. After presenting the approach, the suitability of different textile structures and manufacturing methods is analyzed including concrete printing technologies. Finally, the results of some experimental trials are presented.