This study examines the development of an initial framework for laboratory testing and evaluation of fresh 3D printable concrete mixtures’ performance. Firstly, twelve printable mixtures were prepared consisting of cement, silica fume and three different chemical admixtures: accelerator, retarder, and superplasticizer. The rheological properties such as workability and flowability, were evaluated through flow table testing and a lab-scale additive manufacturing process was held to check their extrudability and buildability properties. To determine mix initial setting time a Vicat device was used (ΕΝ 196-3) while compressive strength measurements (EN 196-1) were also conducted. Secondly, the optimum combination of the aforementioned chemical admixtures was investigated through the application of the Taguchi method which efficiently reduces the number of required experiments. The preliminary results indicated that the addition of any type of chemical admixture improved the paste’s printing properties and performance. Moreover, an indirect correlation between the printable mixtures properties was derived: buildability and workability as well as extrudability and the determination of the initial setting time of each composition. The ideal flowability of the mixtures ranges from 0.20 to 0.25, regardless of the admixture type. Above this range, the printing material is less buildable while below this range the material is not extrudable. The application of the Taguchi method allowed the investigation of the combinatorial effect of superplasticizer, accelerator and retarder on the strain generated on the extruded material during the printing process. Superplasticizer has the major contribution on the strain revealing that flowability is critical for the successful printing process.

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