3DCP Structures (2022-06)¶

During the last decades, 3D concrete printing (3DCP) is evolving rapidly. This newly developed technique allows the manufacturing of structures layer-by layer, based on a virtual model and without human intervention. The elimination of formwork, the reduction in labor time and cost and the increased architectural freedom are generally accepted as the major benefits compared to traditional concrete. At this moment, there are multiple examples of large-scale 3DCP projects worldwide, but the manufacturing process is still hindered from developing its full potential as developments are currently limited to trial and error related to large knowledge gaps in fundamental understanding, experimental methods and predictive models. Additionally, as concrete printing deviates on almost every aspect from mold-casted concrete, newstandardswith regards to the concrete mix design, the manufacturing process itself and the structural performance are required. All these categories should contain technical recommendations to ensure the structural stability, and should exclude the effect of the applied print parameters or cementitious material. To encounter the latter, researchers apply nowadays the ‘Design by Testing’ principle, with a project-specific testing program. This paper shows how structural components are designed based on the ‘Design by Testing’ principle and presents in addition an outlook for the legislation and standardization of future projects.