Column-Slab Interfaces for 3D Concrete Printing: Design, Fabrication and Assembly Strategies

Abstract

3D Concrete Printing (3DCP) currently dominates the scene of digital fabrication with concrete. 3DCP can be utilized on-site or in prefabrication setups. While prefabrication with 3DCP allows for more complex construction elements, it also requires the design for connections and assembly. In the context of prefabrication using 3DCP, this paper illustrates the state of research in the design, construction, and assembly of 3D printed components. It proposes segmentation and fabrication strategies to produce horizontal and vertical structural members of a column-slab building system following the typology of mushroom slabs. The design proposal was experimen tally investigated with two prototypes. Each prototype consists of five elements assembled into 1:1 scale, column-slab connection demonstrators. These prototypes were robotically fabricated using a three-component 3DCP material system and a hardware setup enhanced by a sensor system that supplies online fabrication data for process monitoring and quality control. Based on 3D scans, the recorded fabrication data set is benchmarked against the initial design models to assess the accuracy of the printed elements. Conclusions about process robustness and prefabrication quality of the components are drawn, focusing on the interfaces between components. Finally, mitigation strategies are suggested to enhance the accuracy of the proposed fabrication method.