Review of 3D Printed Concrete: Mix Design

3D printing technology has gained attention for its potential to revolutionize concrete construction by offering improved automation, reduced costs, and enhanced environmental benefits. This paper provides an overview of current research on 3D-printed concrete (3DPC), with a focus on mix design and the fresh and hardened performance of 3DPC. The review examines the differences between 3DPC and traditional concrete, highlighting how factors such as mix composition, binder selection, and aggregate types affect the material's flowability, buildability, and mechanical properties. Notable advancements in optimizing 3DPC mix designs are discussed, including the use of fine aggregates and fibers to improve performance. The paper also covers methods for testing the early performance of 3DPC. Moreover, the review identifies ongoing challenges such as anisotropy and interlayer bond strength, which impact the mechanical properties of 3DPC. The paper aims to provide insights into the current state of 3DPC research and its practical implications for construction.