Automated shotcrete 3D printing - Printing interruption for extended component complexity

This paper introduces a new approach for extending the geometrical freedom of shotcrete 3D printing. Up to now, the printing process has been performed with a continuous material flow to avoid nozzle clogging, which is caused by the solidification of the fresh material within the printing system. However, this requires a continuous printing path for the entire component, which leads to considerable confines in terms of printable geometries. To overcome this restriction, potential factors to control the printing interruption process were determined and quantitatively investigated. Based on 3D specimen data, the most suitable parameter settings for realizing deterministic short term printing gaps without nozzle blockage were identified. For final validation, these settings served in the robotic fabrication of a test element and showed promising results.