Influence of the In-Fill Pattern of the 3D Printed Building Wall on Its Thermal Insulation.

The intensive development of 3D Concrete Printing (3DCP) technology causes constantly increased its share in the construction sector. However, in order to produce products with controlled properties, optimization of the technological process is still required. Automation of production based on additive manufacturing methods streamlines the process by comprehensively manufacturing building components that meet, among others, strength, visual, and insulation requirements. Moreover, the possibility of using computer simulations to assess the properties of the designed elements allows for a multitude of analyzed versions of the constructed partitions, which can be verified at the design stage. Thanks to such an opportunity, the process of designing building elements can be significantly improved. The article presents results related to the assessment of the level of thermal insulation of products that can be produced by additive technology, depending on the applied spatial geometry of the vertical partition and the amount and type of materials used. Eight original solutions of in-fill pattern were designed, for which both Finite Element Method (FEM) computer simulations of thermal conductivity and experimental measurements of thermal conductivity of samples were performed. On the basis of the obtained results, both the correctness of the simulation results for the various analyzed materials and their consistency with the practical results were found. Depending on the investigated geometry, for samples of the same dimensions and using the same material, the differences in the U-factor obtained by FEM analysis amounted to 61%. The best solution from the investigated spatial geometries of the vertical partitions has been indicated. The U parameter in the variant with the best thermal insulation was 0.183 W/m2K, which meets the requirements of Polish construction law. The issues discussed in this work can be the basis for the selection of the best solution possible for practical use during the production of building walls using the 3DCP method fulfilling the guidelines of applicable standards. Furthermore, they can be used as a tool for optimizing geometry in terms of energy savings and reducing waste production by both engineers developing 3DCP technologies and architects using innovative techniques for manufacturing building structures.

Feasibility Review of Aerated Materials Application in 3D Concrete Printing.

Recent years have witnessed a growing global interest in 3D concrete printing technology due to its economic and scientific advantages. The application of foamed concrete, renowned for its exceptional thermal and acoustic insulation properties, not only holds economic attractiveness but also aligns seamlessly with the principles of sustainable development. This study explores various solutions related to 3D printing technology in construction, discussing the design, production, and properties of foamed concrete mixtures. The integration of 3D printing and the potential for automating the entire process offers opportunities to boost productivity and reduce construction costs. Furthermore, the utilization of foamed concrete with its commendable insulation properties will enable a reduction in the usage of materials other than concrete (e.g., mineral wool, facade mesh, and polystyrene), significantly facilitating the recycling process during building demolition. This, in turn, will lead to the preservation of nonrenewable natural resources and a decrease in CO2 emissions. Despite the promising results, there have been limited studies focusing on 3D printing with foamed materials, whereas a survey of the existing body of literature indicates a notable absence of endeavors pertaining to the utilization of aerated concrete within the realm of 3D printing, especially geopolymer composites (GP) and hybrid geopolymer composites (HGP). The outcomes delineated in the ensuing discourse are demonstrative for conventionally used materials rather than the additive manufacturing variant. Hence, this work aims to systematically review existing practices and techniques related to producing foamed concrete with 3D printing technology. This analysis also contributes to the establishment of a foundational framework and furnishes a preliminary basis upon which future endeavors aimed at the 3D printing of aerated concrete can be embarked. The findings from the literature analysis justify the desirability of continuing research on this topic, particularly when considering the potential for large-scale industrial implementation. This article provides a comprehensive state of the knowledge on the development of 3D printing techniques for foamed concrete mixtures. By consolidating and analyzing findings from different studies, this article offers insights into the advancements, challenges, and potential applications of foamed concrete in additive manufacturing processes. This, in turn, contributes to the overall understanding and advancement of 3D printing technologies using foamed concrete as a versatile and sustainable construction material. The encouraging results obtained from the analysis further underscore the need for the continued exploration of 3D printing, especially with an eye towards its industrial-scale implementation.