The use of recycled materials and locally sourced alternative binders in 3D concrete printing has significant potential to reduce carbon emissions in concrete construction.
This is the claim from a study published last week in the journal Buildings investigating the fresh and mechanical properties of low carbon 3D printed concrete incorporating sugarcane bagasse ash and microfibres.
The Queensland University of Technology worked with Everhard Industries of Brisbane to examine the effect of sugarcane bagasse ash (SCBA), a by-product of the sugarcane industry, as a sustainable binder in 3D concrete printing (3DCP).
SCBA was used as a partial cement replacement for low-carbon 3DCP. Printable mixes with up to 25% SCBA were evaluated for flowability, setting time, shape retention, buildability, rheology, mechanical properties and microstructure.
The effects of polypropylene (PP) and steel (ST) microfibres on 20% SCBA content were examined further to understand their contributions to buildability and strength.
Overall, sugarcane bagasse ash was demonstrated as a suitable binder for low-carbon 3D concrete printing, especially at lower replacement levels, with improved mechanical performance. Although the results showed promising strength and printability characteristics, the long-term performance of SCBA-based 3DCP remains a critical consideration for practical implementation.
To address this gap, future investigations will focus on evaluating durability performance, including porosity, drying shrinkage, chemical resistance, and carbonation behaviour of SCBA-based 3DCP.
The study can be openly accessed in Buildings.
About the author
Desi Corbett
Desi is the Editor of Concrete in Australia, at the helm since December 2013, and our weekly news writer since 2016. Focused on concrete and construction for more than 11 years, her expertise in this field forms part of a journalism career spanning three decades. To get in touch please email desi@corbettcomms.com