Printability and shape fidelity evaluation of self-reinforced engineered cementitious composites

Abstract

Incorporating fibers into Engineered Cementitious Composites (ECC) renders it a promising self-reinforced candidate for additive manufacturing, which can effectively address the challenges of reinforcement and automation. Considering this research challenge the current study aimed at designing 3D printable ECC mixes. The problems involved in the printability of ECC such as poor extrudability, buildability and shape retention, were addressed by utilizing the methylcellulose (MC) as a viscosity-modifying admixture. The results indicated that adding 1 % MC improved the fiber dispersion coefficient by 28 % and increased static yield stress in a range of 4 % to 237 % and plastic viscosity in the range of 247 % to 950 % in four different ECC mixes. Accordingly, the dimensional conformity of 3D printed filaments was considerably improved, and all designed ECC mixes meet the extrudability and buildability requirements.