In the last few years, scattered experiences of the application of additive manufacturing in the construction of buildings using 3D printing with robots or automated equipment have emerged around the world. These use a variety of procedures and suggest relevant advantages for the construction industry. In order to identify the different processes and features in development in this field and to guide future research and applications, this article presents a review of the literature on the main aspects involved in the use of 3D printing in the construction sector. The review includes state-of-the-art material mixtures, printing technologies, and potential uses, as well as a novel analysis of building strategies, management systems, and benefits stated about this new approach for construction. It reveals progressive experimentation regarding diverse features, with challenges related to the consolidation of procedures and this technology’s readiness to participate in the building market.

Resumen Este trabajo puso en relieve una experiencia pionera en Chile en lo que se refiere a la gestión de los residuos de construcción y demolición (RCD). El caso estudiado corresponde a la construcción de 17 viviendas unifamiliares ubicadas en un condominio habitacional en la ciudad de Temuco, Región de la Araucanía. Para su implementación se aplicó una metodología basada en un modelo de gestión de residuos desarrollado en España para estimar los RCD. Con la adopción de esta metodología de separación en obra de los residuos, los costos materiales se redujeron a la mitad; también se redujo el costo medioambiental de las obras en construcción. Con ello se ha comprobado que es viable la adaptación de la metodología española a un proyecto de urbanización chileno. Además, la aplicación de esta metodología genera un triple beneficio que repercute en lo ambiental, lo social y lo económico. Al mismo tiempo, se ha comprobado que la reutilización, reciclaje, tratamiento o eliminación de los residuos genera nuevos desafíos en el plano legislativo y de gestión de gobierno, elementos a considerar si Chile aspira a alcanzar estándares de países como Brasil o los de la Comunidad Europea en lo que respecta a la gestión de RCD.

The construction sector undeniably has an impact on sustainability in its three dimensions: economic, social, and environmental. In this context, 3D concrete printing (3DCP) has emerged over the last decade as an attractive technology for transforming this sector. It enables the manufacture of construction elements while saving time, reducing waste, and eliminating the need for molds. However, assessments of the environmental performance of implementing this technology are limited, particularly under representative production conditions. This study evaluates the footprint family indicators, carbon footprint (CF), ecological footprint (EF), and water footprint (WF), of different mixtures of 1 m3 of 3D-printed concrete, with 1m of a high printed wall. These mixtures were made with a proportion of fresh solid aggregates; brick and concrete rubble (as demolition waste (CDW) materials) were used as partial replacements for cement. In addition, the environmental impact of using two printing technologies, gantry and robotic arm systems, is analyzed. The results show that materials are the main source of environmental impacts; the replacement of some of the cement reduces CF and EF by up to 20% and 19%, respectively, while preserving printability and buildability, as demonstrated by the stable fabrication of 1 m-high printed wall elements. However, moderate increases in WF were observed, which were associated with the electricity consumption of waste processing. These results confirm the potential for valorizing CDW in 3D printing mixtures. This environmental assessment under full-scale printing conditions supports sustainability-oriented decision-making in the construction industry.

The aim of this study is to comparatively evaluate the eco-efficient performance of the only two mandatory thermal regulations applied in Chile: The General Urban Planning and Construction Ordinance (OGUC), and the Atmospheric Decontamination Plans (PDA). Considering the PDA of the communes of Temuco and Padre las Casas, and the system limits of UNE-EN 15978:2012 for the "product" and "use" stages, this study covered the indicators of energy, carbon footprint, economic cost and emissions of fine particulate matter (PM2.5), on thermal envelopes of a house. Applying the PDA over the OGUC, the results indicate that: First, the contained energy increases by 12.4%, the carbon footprint by 8.1% and the economic cost by 7.8% in the stage of product; and second, it reduces the demand for heating, fuel consumption, carbon footprint, and PM2.5 emissions, by 19.4%, in the use stage. Finally, the study concludes that, for Chilean homes to improve their eco-efficient performance, an evaluation with a life cycle cost analysis (LCCA) approach, which allows analyzing their evolution over time, must be included in the mandatory thermal regulations that regulate them.

The following paper describes and comments a construction planning platform for the Additive Manufacturing of wall modules, as a set of design and planning acti...