Advances in Binder-Jet 3D Printing of Non-cementitious Materials

Abstract

Additive Manufacturing techniques enable an unprecedentedly fine-grained control over the material they process, both in terms of its geometric distribution and its very composition. With the rapid development of printing methods suitable for the production of large-scale objects together with their respective material systems, applications in the construction industries showcase an expanding portfolio of practical examples. However, considering the more and more critical demand for minimizing the environmental impact due to construction activities, the aim for mechanical stability of a material system is no longer sufficient and needs to be flanked by attentive considerations over the sustainability of its components. The presented research investigates to which extent cement can be either accompanied or replaced by more sustainable material sources, with specific focus on geopolymer and its application in the production of stay-in-place, self-supporting and waste-free formwork systems for modular building components. The manufacturing technique considered for such investigation is binder jet 3d printing, on the basis of the remarkable flexibility it offers in terms of material processing workflow. Three selected material systems, each one introducing recycled and/or repurposed byproducts of different industrial processes (such as stone cutting and demolition activities), will be evaluated and benchmarked against the output of commercially available organic-based BJ systems. Finally, a brief overview of the prototypical binder jet printing setup specifically developed for material testing at construction-scale will be presented, mainly focusing on the control parameters that have a larger impact on the overall properties of printed output.