Integration of Individualized Prefabricated Fibre Reinforcement in Additive Manufacturing with Concrete
This project investigates the implementation of fibre reinforcement in 3D printing with concrete, as by now this task remains largely unsolved, leading to limited, for example compression only applications of additive manufacturing. Our research aims for fully unlocking the inherent potentials of 3D printing, that is to foster material efficient, structurally optimized, and hence sustainable constructions. Automated fabrication processes for the integration of structural reinforcement for additively fabricated concrete elements are being developed. Focusing on innovative fibrous materials instead of conventional steel rebars opens up new challenges same as opportunities encouraging us to score unprecedented structural performance and explore unseen potentials in architectural expression at the same time.
DFG – German Research Foundation within TRR 277 - A 05
Project Aims/ Working program
The aim of this project is to expand the current state of research by developing design methods and fabrication techniques for the application of textile reinforcement in additive manufacturing with concrete. Not only the freedom of form should be increased by using flexible textiles, but also material efficiency by reducing the minimum required concrete cover. Moreover, it is pursued to automate the entire fabrication process from end to end, including the individualized generation of fibre meshes as well as the application of concrete. In detail, at least three different concrete related additive manufacturing processes are addressed: Particle-Bed 3D Printing, Concrete Extrusion, and Shotcrete 3D Printing. For integrating reinforcement the main focus is directed towards fast fibre winding techniques allowing for maximum material yield due to the unsplit material continuity.
Over the past 20 years in Germany, the replacement of steel with textile reinforcement was subject to three major federal funding initiatives, making Germany a leader in the field of textile reinforced concrete. The application of textile reinforcement for repair and strengthening of existing structures was investigated in the Collaborative Research Centre (CRC) 528 in Dresden; the application of textile reinforcement for new building structures was investigated within the CRC 532 in Aachen. Following the two CRCs, the C3 program in Dresden aims at industry transfer of the previously developed fundamentals. Whereas these research initiatives ranged from fundamental research to industry application for conventionally cast or laminated structures, the applicability of textile reinforcement for additive manufacturing with concrete was not investigated in those programs.
For achieving innovative, but substantial results, we orient towards this methodology:
1) Explorative development of a comprehensive set of concepts
2) Critical selection and fast evaluation of most promising approaches
3) Optimization and in-depth investigation of approved techniques
Exemplary for phase 2) an excerpt of the most recent proof-of-concept experiments is shown in the adjacent figure. By manufacturing flat square panels a basic approval for the feasibility of robotically fibre winding reinforcement meshes and additively concreting them by means of shotcrete 3D printing was given, also pointing out weaknesses for future investigations.