What question did this study set out to answer?

To optimize mix designs for 3D printable concrete while balancing environmental impact and material performance.

February 12, 2026

Low carbon dioxide 3D printable concrete: balancing rheology, strength and environmental impact using bentonite and ground granulated blast-furnace slag

Key Points

To optimize mix designs for 3D printable concrete while balancing environmental impact and material performance.
Conducted life cycle assessment (LCA) on various concrete mixtures from literature.
Performed extensive experiments on 20 concrete mixtures with different binder systems.
Tested fresh and hardened properties of concrete mixtures, including flowability and compressive strength.
Measured environmental effects such as carbon dioxide emissions and energy demand.
Using supplementary cementitious materials (SCMs) significantly improved workability.
A 10% increase in bentonite led to a 25% decrease in spreading diameter and a 20% increase in buildability.
Substituting 30% of Portland cement with SCMs reduced carbon dioxide emissions by up to 18% while achieving 25 MPa compressive strength.
Sustainability and printability criteria need to be balanced for optimal mix design.

Abstract

To achieve an optimum mix design for three-dimensional concrete printing (3DCP), a life cycle assessment (LCA) analysis was performed based on an experimental database gathered from the literature. Based on the LCA, a sustainability comparison was conducted on the three-dimensionally printed concretes in the database. Then, an extensive experimental programme was conducted to check the performance of the LCA results of 20 concrete mixtures. This programme considered various binder systems, including Portland cement and supplementary cementitious materials (SCMs). Various tests for fresh and hardened properties were conducted. Finally, a sustainability assessment was performed by measuring environmental effects through carbon dioxide emissions (CDE), environmental damage and energy demand. The findings showed that using SCMs can significantly reduce flowability and increase workability. Specifically, a 10% increase in the amount of bentonite caused a 25% decrease in the spreading diameter and a 20% increase in buildability. A key finding was that substituting 30% of Portland cement with SCMs reduced CDE by up to 18% while achieving a compressive strength of 25 MPa for the optimised mix. In contrast, the sustainability and 3D printability criteria conflicted with the LCA and must be balanced to achieve an optimal mix design for 3DCP.

Demander à l'IA

Bookmark