The innovative realm of filament-based 3D concrete printing (3DCP) introduces new challenges, notably in "buildability"—the ability of freshly deposited concrete to support itself during construction without traditional formwork. This capability is significantly influenced by the chemical and physical properties of concrete, which evolve as the material sets. Intriguingly, the temperature at which concrete is printed plays a pivotal role in determining its initial strength and stiffness. To explore this, a series of experiments were conducted, where concrete samples were subjected to varying temperatures and tested under unconfined uniaxial compression at different stages of setting. Notably, at 75 minutes, both strength and stiffness were markedly affected by the temperature adjustments.
Further investigations included a practical printing trial of a rectangular structure, where parts of the object were exposed to heat lamps. This experiment mirrored the controlled tests, revealing that while small-scale prints were unaffected by external heating, larger structures showed significant variations in buildability. Another trial involved adjusting the temperature of the water used in the concrete mix, with warmer water enhancing the buildability but compromising interlayer strength and increasing the risk of overheating. These findings highlight the complex interplay between temperature and 3DCP, underscoring the need for further research to optimize this promising technology for practical applications.
