Title: Comparative Study of the Mechanical and Durability Performance of Low Carbon Concrete Matrices with Alternative SCMs

Author(s): Eliana Soldado, Hugo Costa, Ricardo do Carmo, and Eduardo Júlio

Publication: Symposium Paper

Volume: 362

Issue:

Appears on pages(s): 930-940

Keywords: alternative waste by-products, compactness, durability, low-carbon concrete (LCC), mechanical properties, paste optimisation, supplementary cementitious materials (SCMs)

DOI: 10.14359/51742019

Date: 6/18/2024

Abstract:
The addition of supplementary cementitious materials (SCMs) to low-carbon concrete mixtures has been investigated in recent years as part of the sustainability of the concrete sector. Recently, most traditional SCMs, such as fly ash and blast furnace slags, have become unavailable in several developed countries, mostly due to environmental restrictions. Consequently, several new by-products from fast-growing sectors are being considered as potential replacements for traditional SCMs. However, the durability of these new by-products in low-carbon concrete has not been thoroughly explored. As a result, this paper presents the first part of a project related to an extensive experimental characterization, in which low-carbon concrete with high compactness, paste optimization, and partial cement replacement by the addition of waste by-products from the agricultural, metallurgical, paper, and glass industries is studied. Alternative SCMs including rice husk ash, biomass fly ash, rock wool residues, or waste foundry sand are incorporated into corresponding mortar matrices and the results concerning the mechanical properties (flexural and compressive strength) and durability (capillary water absorption, surface electrical resistivity, and carbonation resistance) are presented and analyzed. The outcomes indicate that it is possible to reduce the Portland cement content without compromising the mechanical and durability properties of the concrete.