The additives in common concrete technology have already been researched in various aspects. In the act of 3D printing development the large experiences of common technology may be applied and upgraded to satisfy demands and challenges of promising technology. The objective of this study was to examine the effects of chemical additives on water distribution with the main aim to improve the hardened properties and to improve the shape accuracy of 3D printed specimens using selective cement binding activation method. To reach the improval the effect of different additives in combination with different cement types, water to cement ratios and cement to aggregate ratios was investigated. With the selective cement activation method, produced specimens were printed for each combination of studied parameters, in order to determine which mixture produce specimens with the highest strength and shape accuracy. For each combination of parameters also specimens with only water as an activation fluid were printed as a reference. The water distribution was quantified after printing. Compressive and bending tensile strengths were tested according to DIN EN 196-1. Shape accuracy was defined by measuring the dimensions of specimen’s cross-section area. Those properties were examined for each combination of parameters after 1 day and 7 days. Results showed that PVA possess the best properties among the studied additives. When PVA additive was used, strength of printed specimens was increasing with increasing of water to cement ratio. Moreover, the shape accuracy was also improved.
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