Abstract
3D printing offers transformative potential in construction, yet optimising the performance of cementitious materials before and after extrusion remains a critical challenge. This study presents a performance-based mix design framework targeting extrudability, buildability, and layer stability, while evaluating the individual and combined effects of cement (C), hydrated lime (L), recycled tile powder (T), and chemical accelerators (A). Results reveal that their synergy significantly enhances rheology, yield stress, and print stability, while maintaining sufficient flowability. A specifically optimised mix, CLTA, achieved a 40% reduction in shrinkage, improved interlayer bonding, and markedly increased mechanical strength, modulus of toughness, and failure strain, key for energy absorption in printed structures. Environmentally, CLTA reduced raw material demand and improved eco-strength and costefficiency by up to 20%, promoting circularity and resource efficiency. The findings provide a robust pathway for designing high-performance, sustainable 3D-printed mortars, integrating engineering functionality with ecological resilience, paving the way for broader adoption of additive manufacturing in construction.
| Original language | English |
|---|---|
| Number of pages | 34 |
| Journal | European Journal of Environmental and Civil Engineering |
| Early online date | 8 Dec 2025 |
| DOIs | |
| Publication status | E-pub ahead of print - 8 Dec 2025 |
Data Availability Statement
The data that support the findings of this study are openly available in Mendeley Data at http://doi.org/10.17632/pw27mwn72z.1Acknowledgements
The authors would like to acknowledge TARMAC Company for supplying the materials. Special thanks are extended to Assoc. Prof. Dr. Dimitris Nikolaides for providing the tile powder and for his valuable support throughout the research process. We are deeply thankful to Assoc. Prof. Dr. Benny Suryanto and Assoc. Prof. Dr. Craig Kennedy for granting access to equipment in the Materials Lab at Heriot-Watt University. Finally, we acknowledge the valuable support of the dedicated team of Energy, Geoscience, Infrastructure and Society’s technicians; particularly Graham Sorley, Alastair MacFarlane, and Martin Aitkin, for their assistance and expertise during the experimental work at Construction Materials Lab at Heriot-Watt University. The authors used ChatGPT (OpenAI, GPT-5 Thinking, October 2025 version) solely for minor language editing (grammar and phrasing). All intellectual content, analysis, and conclusions are the authors’ own. No generative AI tools were used to create figures, tables, data, or code. The authors reviewed and verified all AI-assisted edits for accuracy and integrity.Keywords
- 3D printing
- cementitious mixtures
- mechanical properties
- printability
- sustainability
- viscosity
ASJC Scopus subject areas
- Environmental Engineering
- Civil and Structural Engineering
