Published Paper Details:

High Ductility Cementitious Composites (HDCCs) are emerging as suitable materials for 3D concrete printing due to their superior tensile strength and crack resistance. These composites typically contain a high volume of micro steel fibers to improve ductility and structural integrity. However, excessive fiber content negatively impacts the fresh properties of the concrete, increases porosity, reduces durability, and significantly raises production costs. To overcome these challenges, this study introduces a novel nano- coating technique where graphene oxide (GO) is applied to micro steel fibers using polyvinyl alcohol (PVA) as a binder. This coating improves the bond between the fibers and the cement matrix, enabling better stress distribution and crack control. As a result, the required fiber dosage can be reduced without compromising mechanical performance. Mechanical tests such as compressive strength, direct tensile strength, and flexural tests were conducted to assess the modified composite. Additionally, self-healing behavior was examined by pre-loading samples and allowing a healing period. The results indicate that nano-coated fibers not only enhance strength characteristics but also promote autogenous self-healing, making the material more durable and cost-efficient for advanced 3D concrete printing applications.