6.10 The direct/indirect use of additive manufacturing in construction viscous mixtures

The project proposes a study on the construction potential in civil engineering and architecture by combining additive manufacturing technology and viscous materials. The research will be carried out on both the direct extrusion of viscous doughs using large-scale printing equipment and the indirect use of additive manufacturing, as Fused Deposition Modeling, to produce casting moulds for viscous doughs. Its primary aim is to demonstrate how digital fabrication, and especially additive manufacturing, can be used to create innovative building elements and systems with a dual purpose:

• developing a building systems for a circular economy in construction through the re-use of natural and waste materials with a zero-kilometer provenance;
• proposing a system of building shapes that cannot be realized with traditional fabrication technologies using viscous dough.

The research will be developed simultaneously in four different areas:

• The optimization of mixtures made of natural and waste materials by introducing chemical components and physical-mechanical actions to improve the fresh-state properties required by additive manufacturing, the hardened-state technical performance and quality of both material and fabricated elements;
• The development of tailored additive manufacturing systems through the integrated use of differentiated handling systems and differentiated extrusion systems;
• The development of an innovative process of architectural composition that integrates computational and generative design with digital fabrication techniques in the viscous additive manufacturing field;
• The development of a structural design approach which integrates the main features of the digitally manufactured elements (e.g., layered structure, free-form shapes etc.) along with a proper finite element simulation strategy to be used for the acceptance/compliance of the new products;
• The design and realization of a demo-prototype by using large scale printing available at UniNa which reflects the overall design-to-fabrication strategy of the project;
• The implementation of life cycle assessment (LCA) models to evaluate the eco-sustainability potential of the materials and manufacturing processes developed in the project.

The research activities will be finalized through the implementation of two experimental pilot sites. These will be developed to address the following challenges:

• Conceptualise, design and test the construction of a complex spatial element using a viscous material which recycles waste and is optimized for high performance in direct additive manufacturing technology; the process should use as few construction support systems as possible such as (support and scaffolding/ support and framework) ribs and scaffolding to demonstrate the direct applicability of the construction system;
• Thinking, designing, and testing the construction of a complex spatial system managed by computer aided design using open source computational and generative design software and 3 then its construction by indirect use of casting moulds; this process should also involve as few construction support systems as possible, such as support and scaffolding, to demonstrate the direct applicability of the construction system.
• Tailoring the composition of the printable mixtures and the characteristics of the additive processes to reach an “optimum” combining technological performance and environmental/energy impact.
• Demonstrate the structural feasibility of the concepts and the viability of viscous mixtures used in the direct/indirect additive manufacturing.