Mechanical Strength, Durability, and Environmental Properties of Ternary Blended Self-Compacting Cementitious Mortar Containing Class F Fly Ash and Waste Ceramic Powder

In this paper, the mechanical as well as workability and durability properties of Self-Compacting Mortars (SCMs) made of different contents of Waste Ceramic Powder (WCP) and class F Fly Ash (FA) were experimentally assessed. To this end, the fresh properties of the SCM mixtures were evaluated through detailed examination of both mini slump flow and mini V-funnel tests. Ternary SCM mixtures are characterized by more flowability and passing ability than the control mix. The compressive and flexural strength, water absorption, and electrical resistivity tests were also carried out at different curing ages. The obtained results revealed that the compressive and flexural strength of the ternary SCM samples were lower than those of the control mix, especially at the ages of ۷ and ۲۸ days. However, there was a strength gain between ۲۸ and ۹۰ days due to the pozzolanic reactivity of both FA and WCP. Water absorption of the ternary SCM specimens containing FA and WCP followed a decreasing trend, thus highlighting the filling effect of the used pozzolans. Ternary SCM samples had considerably higher electrical resistivity (up to ۱۴۴ % at ۹۰ days) than the binary blends and control mix. Scanning Electron Microscopy (SEM) images confirmed that application of FA and WCP would fill in the pores and micro-cracks. Based on the obtained results, it can be concluded that both FA and WCP act more as a filler rather than a reactive pozzolanic material. Finally, the environmental analysis results revealed that replacement of ۵۰ % of the Portland cement with ۳۰ % FA and ۲۰ % WCP would result in a reduction in the carbon footprint and energy demand by ۴۷ % and ۲۹ %, respectively.

Keywords:

Self-compacting mortar (SCM) , Waste ceramic powder (WCP) , Fly ash (FA) , Mechanical properties , Durability , Environmental Impact