Title: Mixture Proportioning Approach for Low-CO2 Concrete Using Supplementary Cementitious Materials

Author(s): Keun-Hyeok Yang, Sung-Ho Tae, and Dong-Uk Choi

Publication: Materials Journal

Volume: 113

Issue: 4

Appears on pages(s): 533-542

Keywords: life-cycle assessment; low-CO2 concrete; mixture proportions; supplementary cementitious materials

DOI: 10.14359/51688992

Date: 7/1/2016

Abstract:
This study developed a simple and rational mixture proportioning procedure for low-CO2 concrete using supplementary cementitious materials (SCMs) such as fly ash (FA), ground-granulated blast-furnace slag (GGBS), and condensed silica fumes (SF). Lifecycle CO2 reduction ratio was critically considered as one of the targeted requirements. The effect of SCMs on CO2 reduction and the compressive strength of concrete was examined by a nonlinear multiple regression analysis using a total of 12,537 datasets, which produced schematized data allowing for the straightforward design of SCMs for satisfying the targeted requirements. Considering the determined substitution level of SCMs for a targeted CO2 reduction ratio, unit binder content and water-binder ratio (W/B) were formulated for the designed compressive strength and entrained air content of concrete. The fine aggregate-to-total aggregate ratio (S/a) was determined from the quadratic formula of a parametrized value for a targeted initial slump of concrete. Overall, the developed procedure is expected to encourage the practical production and application of low-CO2 concrete in the ready mixed concrete field.