In the digital transformation process …
… that is already happening in all production sectors, a new fabrication model has been developed, based on digital information; one that yields objects on site, eliminating the need for transport, through an additive system that leaves no wastes, is sustainable, relies on open softwares, and allows making one-of-a-kind pieces at low cost.
In degree of implementation of this method, the building sector has yet to catch up with other sectors, especially those centered on fast prototyping. Both the technology and the applications of 3D printing for construction are still at an embryonic stage of development. The technology has three main uses in current architectural purposes: the making of work models in projects, the large-scale printing of buildings, and the development of customized components of complex constructions.
In the first place, 3D printing is a tool for making models of preliminary projects, and for carrying out three-dimensional communication during the process of designing and creating buildings. This application is generalized thanks to the low cost of 3D printers and the use of three-dimensional digital models in those processes. The most disruptive of the new applications has been the development of largescale printing in the field of construction, which up to now had presented great difficulties with respect to materials as well as to building procedures owing to a series of factors, among which we can mention the specificity of the sector, the cost of the necessary machinery, and an absence of clear methodological patterns. Nevertheless, printing via personalized components is more feasible in the short run and can have a great impact on the future of constructions, especially with the robotization of the process.
The Large Scale
Current 3D printing processes are mainly centered on rapid prototyping (RP). Stereolithography (SLA), selective laser sintering (SLS), and fused deposition modeling (FDM) are based on a technique of layer-by-layer creation which presents a series of limitations, such as the need for continuity in the layers, the presence of support material in certain parts, or the need for manual polish or finish post-processing.
The adaptations for large-scale printing generally imitate desk or small-scale printers through a literal increase of size. We can mention two main methods oriented towards large sizes, exemplified by D-Shape (Dini, 2016) on the one hand, and the Canal House (DUS Architects, 2016) on the other. The former works with a bridgecrane and a nozzle that pours binding adhesive on a layer of raw structural material. This system requires huge quantities of material, which results in large volumes of waste. Given the cost of infrastructures of this kind, it is not efficient to dislocate production through this system, which is an additional inconvenience.
The project by the Dutch office DUS Architects is an effort to build a house of the traditional type that abounds along the canals of Amsterdam. This project presents a pavilion which, in turn, introduces other pavilions. It is essentially a gigantic portable version of the desktop printer Ultimaker, which has been called ‘Kamermaker’ and is moved within a silver-plated, 3.5 meter tall container. In this case, the material system by which the dwelling will be built is a framework of components of polypropylene linked together by secondary structures of bundles of steel; in the case of the facade, a steel cable will be used.
On the other hand, Contour Crafting (Khoshnevis, 2016) is also based on large infrastructures, although its system of deposition by layers is more efficient: in this case the nozzle pours concrete or fused material directly on the necessary zones. Both techniques are inexact and geometrically imprecise, producing effects that cannot be considered definitive. Notwithstanding, here is one of the most used techniques when it comes to making large structural elements in concrete. ProtoHouse, developed by the Architectural Association School’s Design Research Lab and Softkill Design in 2013, offers an interesting hybrid solution of elements 3D-printed in the plant and assembled on site; possibly the best solution to the current situation of technology. In 2012 Foster + Partners designed a home on the moon for four persons, to be made of lunar soil through a robotized printer that would create a protective frame based on natural biological systems (see AV Monographs 163-64).
Arquitectura Viva nº187: Spanish Solutions: Under 50 the Crisis Generation (Pp: 70-75. Vol. 187:9). Versión impresa ISSN 0214-1256.
Digital Transformation in Construction 