Structural and Functional Performance of 3D-Printed Light-Transmitting Foamed Concrete with Different Cavity Geometries and Fiber Orientations (2026-04)¶

This study investigates the structural and functional properties of 3D-printed light-transmitting foamed concrete (LTFC) composites, designed with various cavity structures (Square, Triangle, Honeycomb) and fiber orientations (X/Y direction). The experimental results demonstrate that the mechanical performance is highly dependent on both the structural topology and fiber alignment. Y-Fiber specimens exhibited superior flexural strength, reaching up to 5.22 MPa in the triangular configuration, due to effective crack-bridging mechanisms. In contrast, X-Fiber specimens achieved higher compressive strength, up to 16.26 MPa, benefiting from multi-directional stress dispersion. All configurations exhibited ductile failure, a significant improvement over conventional concrete's brittleness. The honeycomb structure demonstrated the best buildability, attributed to its efficient hexagonal stress distribution. Functionally, the composites provided excellent thermal insulation, with thermal conductivity below 0.23 W/(m·K). Simultaneously, they maintained considerable light transmittance, with X-Fiber specimens transmitting up to 49.96% of light, as shorter fibers reduced scattering. These findings underscore the critical interplay between design and performance, presenting the 3D-printed LTFC as a promising multifunctional material for modern building envelopes that integrate load-bearing capacity, energy efficiency, and natural lighting.