Numerical Assessment of Thermal Bridging Effects in 3D Printed Foam-Concrete Walls (2024-10)¶

Integrating smart technologyand advanced materials in the construction industry has revolutionized traditional building practices, enhancing efficiency, sustainability, and overall performance. Researchers and professionals in the construction sector have shown significant interest in threedimensional concrete printing (3DCP) for automating structural engineering tasks. Despite its potential as a sustainable solution to modern construction issues, there is a lack ofresearch on the thermal insulation performance ofthree-dimensional printed concrete (3DPC) building envelopes, and the potential for integrating foam concrete (FC) to enhance energy efficiency has not yet been studied. This paper presents a numerical analysis examininghow different infill geometries affect the thermal performance of3D-printed foam concrete (3DPFC) lattice envelopes. Six lattice structures were designed with identical thickness, height, length, and comparable insulation areas. The effects of the contact (intersection) area ofwebs with the interior face shell, webs, and infill rows on the thermal performance ofgranularly insulated envelopes were studied. The effectiveness ofinsulation was also established. The findings indicate that the thermal transmittance of3DPC envelopes correlates directly with the contact area ofthe webs and the interior surface, with U-values ranging from 0.151Wm2·K to 0.652W/m2·K. Notably, the absence ofdirect connections between exterior and interior surfaces enhances insulation efficiency, with double-row structures achieving up to 94% insulation efficiency. However, when there is a direct connection between the two surfaces, the thermal performance ofthese envelopes is mainly affected bythe contact (intersection) area ofthe webs with the interior face rather than the number ofwebs. Byintegrating foam concrete and doublerow walls, this studydemonstrates an innovative approach to reducing thermal bridging and improving energyperformance in 3D-printed construction. The results offer novel insight into optimizing the thermal behavior of3DPC systems for sustainable building practices.