Institut für Tragwerksentwurf  |  FK3 Architektur Bauingenieurwesen Umweltwissenschaften   |  Technische Universität Braunschweig

Developments in the construction industry regarding digital design and fabrication methods are mostly guided by the standard of industrial production. Most load-bearing structures are usually composed of linear mass-intensive bending components and neglect lightweight form-active structures. In the near future, the efficient use of materials and “grey embodied” energy will have a crucial importance for the implementation of sustainable construction. Instead of avoiding complexity at the cost of increased masses, the goal will be to save mass by using structural efficiency through combining the latest developments in material technology with the digital planning and production methods. The aim for high-tech materials such as ultra high performance fibre reinforced concrete (UHPFRC) must be to develop material appropriate non-standard joint principles that are produced economically despite of increased complexity. Exploring the fundamental principles of these new UHPFRC lightweight structures, members and their jointing systems, are the targets of this research project which is part of the priority programme 1542 established by the German Research Foundation (DFG).
The paper will present how the “Digital Workflow” allows to design, calculate and produce new precast UHPFRC members. Within the established “Digital Workflow” of design, from detailing to construction, a new precast system with short erection time on site was developed. The pre-stressed modular system of thin walled shell and spatial members with complex geometries and non-standard jointing systems made of UHPFRC was theoretically and experimentally investigated. Because of the excellent shaping capabilities with only small tolerances of casted UHPFRC-elements a CNC manufactured formwork system was created to build individual and serial parts. The design of members was based on minimizing embodied resources while maximizing material efficiency. Therefore the developed members and non standard joints make use of geometric stiffness through curvatures and folding.

Keywords: UHPFRC, modular, non-standard jointing principles, lightweight construction, resource efficiency, digital workflow