**3. Materials and Methods**

### *3.1. Materials*

In this study, cement-based mortar was developed for 3D printed paving stones. The cement-based mortar comprises cement, water, and a set-accelerating admixture. In this process, the pumpability and the stability of the extrusion were considered as the major properties of the cement-based mortar.

The main material used to produce paving stones is CEM I 42.5 N Portland cement, which is in accordance with the standard TS EN 197–1. The water-to-cement ratio was set as 0.4, and Polisan Antiton 100 was used as set accelerating admixture to prevent collapses during the printing process.
