From waste to circular economy: Exploring the sustainable potential and engineering properties of self-compacting mortars

This study focuses on evaluates 22 produced sustainable self-compacting mortars from a circular economy perspective and explores their engineering properties (durability, economical, environmental, fresh, mechanical, microstructural, and thermal). Pumice and recycled concrete aggregate (RCA) were used as aggregates, silica fume and fly ash as supplementary cementitious materials (SCM). The 90-day compressive strengths indicate that significant strength reductions did not occur until using 10% RCA, while the use of SCM made positive contributions. A comparison of Ref-3 with the 10SF-RCA10 series reveals that the 90-day compressive strength is 39.5–47.9 MPa, respectively, an increase of approximately 21.3%. The results of high-temperature tests revealed significant strength losses, especially in specimens exposed to 600 and 900 °C. At 900 °C in particular, the compressive strength decreased by 50–70% and the flexural strength by 70–85%. The findings of the thermal conductivity tests emphasize the potential contribution of RCA to the construction of sustainable building materials in evaluating the influence of SSCM on thermal conductivity and energy efficiency. From a microstructural point of view, the use of silica fume and fly ash in certain proportions positively affects the mortar's internal structure, strength and density. For the extensive review of environmental and economic outcomes, global warming and sustainability potential were analyzed using different scenarios. The combined use of RCA and SCM significantly contributes to global warming and sustainability potential. The broad assessment of the economic characteristics revealed that transport distances are crucial and need to be considered for sustainable production. [Display omitted] •Different scenarios highlighted significant impacts of transport distances on GWP.•Cement and NA needs increased with new buildings to be built after the earthquakes.•The use of RCA and SCMs can reduce the consumption of natural sources and cement.•The post-earthquake construction demolition waste can be valorized in SSCM.•The sustainability potential of SSCM can be improved by using SCMs and RCA.