Title: Low-Carbon Concrete Achieved through Rheology Modification

Author(s): Lesley Ko, Jeffery Bury, Charles Nmai

Publication: Symposium Paper

Volume: 362

Issue:

Appears on pages(s): 570-584

Keywords: chemical admixture, finishability, low-carbon concrete, pumpability, rheology modifying, sustainability

DOI: 10.14359/51741012

Date: 6/14/2024

Abstract:
Maintaining workability can be a challenge when the total cement content of a concrete mixture is minimized in order to lower the carbon footprint. This is especially the case in everyday concrete where Portland cement content is mostly optimized for a targeted strength. Unlike high-performance or self-consolidating concretes (SCC) which commonly have high cement or cementitious materials contents, a minimum paste volume is generally required in normal strength concrete (NSC) mixtures to ensure adequate workability for the application and to be acceptable in the field. In this study, a new generation of rheology-modifying water-reducing admixture that improves concrete rheology is used to further reduce cement content and provide favorable workability for concrete applications. Comparisons to reference concrete are presented for their fresh and hardened properties, including plastic viscosity, dynamic yield stress, finishability, pumpability, and targeted strength. By combining concrete technology and this new rheology modifying water-reducing admixture, an economical, workable low-carbon concrete can be achieved.