Fresh and Hardened Properties of 3D High-Strength Printing Concrete and Its Recent Applications

3D printer is the device that quickly produces the models designed on the computer using different materials without the need for a mould. In this study, the properties of the 3D printer developed by Iston and the complementary components such as concrete pump, concrete transmission hose, printer nozzle head which are synchronized with this printer are given. In addition, the mix design of fibre-reinforced and grain size limited high-performance concrete, which is used in this printer, and properties of fresh and hardened concrete are examined. In this context, mechanical properties of casted and printed specimens were compared. In addition, mechanical behaviour of printed samples in different directions was also investigated. Results of both compression and flexural tests show the mechanical properties of the printed specimens differed slightly in directions. When the casted and printed samples are compared, the strength of the casted samples is slightly higher than the printed samples. Although the mechanical properties of the casted and printed samples differed, targeted results were obtained for the strength of the printed samples. In the last part of the study, examples of street furniture produced in 3D printer using white cement mixture for decorative purposes are given. Although there are studies in the literature about 3D concrete printing, there are not any studies on street furniture produced in 3D printer.