Ireland: Researchers from Trinity College Dublin’s School of Engineering have developed a 3D printed cement-free geopolymer made with a bauxite refining residue that contains over 30% industrial waste. The material is 3D printed, meaning that typical projects can be completed in weeks rather than months, avoiding the need for traditional moulds and formwork, and reducing waste. Construction is also automated and can print complex curves that may be impossible or too expensive to build traditionally, according to Trinity College Dublin. In the trial, conducted at Harcourt Technologies, the team demonstrated how the red-brown material could be mixed, pumped, extruded and printed. According to preliminary assessments, the material could reduce embodied CO₂ emissions by approximately 70% compared to ordinary Portland cement.
Professor Sara Pavia from Trinity College said “This successful trial demonstrates how local industrial residues can be transformed into functional, adaptable and visually distinctive construction materials. The material and method of production and printing essentially delivers two environmental benefits: it reduces dependence on carbon-intensive cements, and creates a high-value use for industrial residues. The significance of the material itself extends beyond cement replacement. It is a flexible binder platform whose composition, rheology, setting behaviour and early-age performance can be tailored to different manufacturing processes and construction applications.”
This work has its roots in a wider research project funded by Research Ireland, SISK, FLI Precast Solutions, McGrath Quarries, Techcrete and Roadstone. The industries bring together their expertise in material development, concrete production, precast manufacturing, construction delivery and digital fabrication. The next challenge is scaling the material from laboratory batches to the quantities and consistency required for industrial equipment. The next steps will focus on mechanical performance, durability, reinforcement, long-term stability, process control and regulatory compliance.
