Printability and Shape Stability of Cement Mortar Incorporating Low Volume of Micro-Polypropylene Fiber for 3D Printing Application

This study investigated the printability and shape stability of cement mortar with micro-polypropylene fiber for 3D printing application. Mortar mixes with fiber content from 0% to 0.1% were tested for properties relevant to printable cement mortar, including initial printable time, flow, and viscosity. The results showed that fiber addition decreased flow percentage, and initial printable time but increased viscosity (in terms of shear stress). The fiber addition also impacted the filament cross-sectional shape, making the width narrower and the height taller. The relationship between the initial printable time and viscosity test indicated that the shear stresses between 494 to 580 Pa are suitable to start the printing these mortars.