Abstract
There is an increasing trend in research projects and case studies to demonstrate the potential of Additive Manufacturing (AM) with concrete, better known as 3D concrete printing. Like ordinary construction, the latest upgrades on this topic are strongly focused towards improving eco-sustainability in terms of low-carbon materials. Low-carbon binders’ alternative to Portland cement and the utilisation of selected waste materials in place to virgin aggregates has high potential in fulfilling the sustainable development goals. In this paper, an experimental study was performed by incorporating ground waste tire rubber aggregates of different size gradation (0–1 mm and 1–3 mm) and replacement levels (50 v/v% and 100 v/v%) in a “greener” alkali-activated mix designed for 3D printing applications. First, the experimental program involved the optimization of mix design rheology and printing parameters to successfully integrate rubber aggregates into the printable alkali-activated mixtures. Then, a comprehensive characterization, including static mechanical testing, dynamic thermo-mechanical analysis, thermal conductivity testing, and acoustic insulation measurements was conducted. Comparison with identical Portland-based rubberized formulations designed for AM revealed better mechanical isotropy, flexural strength, thermo-mechanical behaviour, heat insulation, and high-frequency acoustic insulation for alkali-activated composites. The influence of rubber aggregate size on the fresh and hardened state behaviour of the mixes was also studied and discussed. Keeping the losses in mechanical strength restrained, the rubberized composites designed in this study have demonstrated significant thermal and acoustic insulation properties that are desired for energy-saving applications in buildings. The research verified the practicability of using waste aggregates in low-carbon binders for sustainable lightweight and thermo-acoustically effective applications, establishing an attractive starting point to address future research on material optimization for practical purposes.
Original language | English |
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Pages (from-to) | 3098-3117 |
Number of pages | 20 |
Journal | Journal of Materials Research and Technology |
Volume | 24 |
Early online date | 1 Apr 2023 |
DOIs | |
Publication status | Published - May 2023 |
Bibliographical note
Funding Information:The authors would like to express their sincere gratitude to Eng. Ettore Musacchi (ETRA) for the supply of the rubber aggregates used in the research. The authors also thank Prof. Jacopo Tirillò and Prof. Fabrizio Sarasini (Sapienza University of Rome) for technical support in DMTA measurements.
Publisher Copyright:
© 2023 The Author(s)
Keywords
- Alkali-activated materials
- Anisotropy
- Extrusion-based concrete 3D printing
- Ground waste tire rubber
- Mechanical properties
- Thermo-acoustic insulation analysis
ASJC Scopus subject areas
- Ceramics and Composites
- Biomaterials
- Surfaces, Coatings and Films
- Metals and Alloys