Effects of Different Orientation Angle, Size, Surface Roughness, and Heat Curing on Mechanical Behavior of 3D Printed Cement Mortar With/Without Glass Fiber in Powder-Based 3DP.

Powder-based (inkjet) three-dimensional printing (3DP) technology presents great promise in the construction industry. The capacity to build complex geometries is one of the most appealing features of the process without formwork. This article focuses on the vital aspect of using a modified powder (CP) instead of commercial powder (ZP 151). It also discusses the effects of the size of specimens and the curing process of 3DP specimens. This article presents not only the improved mechanical properties of the mortar that are revealed through a heat-curing procedure but also the properties of the reinforced mortar with chopped glass fibers. Experiments are conducted on cubic printed mortar specimens and cured in an oven at different temperature regimes. Tests show that 80°C is the optimum heat-curing temperature to attain the highest compressive and flexural strength of the specimens. The orientation angle has a significant effect on the mechanical behavior of printed specimens. Therefore, specimens are prepared by printing at different orientation angles to compare the mechanical properties of common construction materials. Powder-based 3DP has three planes (XY, XZ, and YZ) along which a load can be applied to the specimen. The mechanical strength in each direction across each plane is different, making it an anisotropic material. For CP specimens, the highest compressive strength was obtained using a 0° rotation in the printing orientation of the XY plane. For shear strength, a 45° orientation gave the optimum result, while for tensile and flexural strength, a 0° orientation provided the highest values. The optimum strength for ZP 151 specimens in compression, shear, tension, and bending was obtained by printing with orientation angles of 0°, 30°, 0°, and 0°, respectively. Finally, laser scanning of the printed specimens has been conducted so the surface roughness profiles for the 3DP specimens of ZP 151 and CP can be compared and presented.