Sustainable natural pozzolana concrete – A comparative study on its environmental performance against concretes with other industrial by-products

Abstract

With increasing environmental sustainability concerns in the construction industry and a demand for producing more durable and sustainable concrete, effort is devoted to producing concrete with Ordinary Portland cement (OPC) being substituted by alternative binder materials. By considering the compressive strength, the comprehensive environmental performance of natural pozzolana in concrete was evaluated comparatively by developing six mix-designs of concrete with OPC, and commonly used industrial by-products as supplementary cementitious materials such as fly ash (FA) and ground granulated blast furnace slag (GGBS) based on the lifecycle assessment (LCA) approach. The results show that comparable compressive strengths can be achieved for the use of 20% and 30% volcanic ash (VA) against conventional SCMs. Using the volume as functional unit, the LCA results have demonstrated that higher environmental savings are associated with VA concrete compared to that of OPC, GGBS (30%) and FA (25%), but almost similar when 50% GGBS is used. For example, 15–24% and 10–19% lower global warming potential are associated with VA concretes compared to that of OPC and FA concretes, respectively, but much higher saving is found when considering the strength of the concrete, as they are about 11–12%, 10–11% and 29–30% compared to that of GGBS, FA and OPC concretes, respectively. The results can be used as valuable guidelines for VA-based in sustainable concrete production, which would further enhance the sustainability of the concrete industry.