Abstract

Cement production is one of the major contributors to higher carbon dioxide (CO2) emissions, leading to a higher carbon footprint. Hence, reducing cement demand will preserve natural resources and reduce CO2 emissions associated with cement production. Moreover, the reliance on cement manifested the concern associated with the disintegration problems of the long-standing structures, indicating the handicaps of Portland cement as a binder. Nowadays, the development of cement-less sustainable concrete is gaining significant attention due to its ecological value and environmental benefits.

On the other hand, Alkali-Activated Materials (AAMs) are considered part of the future toolkit towards achieving sustainable binding systems. AAMs are likely achieved by the utilization of low-carbon footprint materials (entitled “precursors”) activated in alkaline environments (induced by “activators”). In recent research, there has been an increasing emphasis on the utilization of these advanced cementing systems in the production of concrete for particular purposes such as SCC. Therefore, the main goal of Alkali-Activated Self-Consolidating Concrete (AASCC) is to produce zero-cement SCC without sacrificing its quality and performance. One of the main challenges facing AASCC application on the industrial scale is the development of effective mineral and chemical admixtures to improve the fresh, mechanical, but most importantly, durability performances.

The durability of AASCC is a subject of controversy, especially when exposed to sulfate attacks. Furthermore, the adequacy of the standard sulfate immersion tests raises more concerns about the reported behavior. As is obvious from the research conducted by several investigators aiming for evaluating the dual aspects of AAMs potential and field-like quality. Since the resistance of AASCCs to external sulfate attack was not widely investigated as regular alkali-activated concretes (AACs). The current research work has introduced an integrated testing strategy that includes the exposure of AASCC to multiple field-like damaging factors, i.e., various cations, controlled pH, partial immersion, and wetting-drying cycles. This has helped create a fundamental knowledge of the durability of a wide range of AASCC mixtures to different external sulfate attack scenarios and capture the failure mechanisms of a wide scope of AASCC mixture designs.

Keywords: Sustainability, Alkali-Activated SCC, Sulfate Attack, Integrated Testing