Use of a 100% Seashell Aggregates and Alkali-Activated Slag Cement (AASC) for sustainable concretes
Résumé
The continuous and excessive use of both ordinary Portland cement (OPC) and natural aggregates for concrete production poses a threat to meeting sustainable goals. More alternatives to these materials are required to mitigate the environmental effect of the industry. One of the ways is to rely on the use of existing waste, industrial or non-industrial, to lessen the extraction of natural resources for the production of aggregates and binders. In this context, this study explores the development of sustainable concretes using 100% seashell aggregates and alkali-activated slag cement (AASC), both of which are produced from waste sources. The concretes were made using aggregates from the shells of the Pecten maximus (scallop). The water-to-cement (w/c) ratios were varied to find the optimal workability. The fresh state, mechanical properties and durability of samples were tested at the varied w/c ratios. A performance based approach was used in the assessment of their properties. A compressive strength of 30 MPa was set which was met at a w/c of 0.35 and 0.30.