ABSTRACT
In recent years, Portland cement concrete has gained attention in the Brazilian road infrastructure sector due to economic advantages compared to asphalt concrete. Regarding environmental benefits, one of the main challenges to increasing the confidence of industry and agencies concerns the carbon dioxide emissions associated with Portland cement production. Nevertheless, Portland cement production in Brazil is one of the least carbon-intensive in the world, supplementary cementitious materials are widely available, and renewable sources supply 63% of the industrial sector’s energy demand. In this context, this paper investigates a strategy to reduce the carbon footprint of concrete pavements by replacing Portland cement with red ceramic waste from local sources in mixtures with compatible compressive strength and durability for equivalent pavement service life. A life cycle assessment helped quantify the life cycle impacts of 1 km of road pavement (including the subbase, base, and surface layers) from the duplication project of one of the most critical federal highways for cargo transport in Southern Brazil. The life cycle impacts, determined through the EN15804 impact assessment method, comprehend the production (A1 to A3), construction (A4 to A4), and maintenance (B2) stages of the pavement life cycle. Results confirmed about 15% reduction in the pavement carbon footprint with a 40% Portland cement replaced with red ceramic waste in C45 concrete. The production stage controls the carbon footprint of the concrete pavement. Restoration and periodic conservation services are hotspots in freshwater-related environmental impacts as well as impacts causing damage to human health, associated with photochemical ozone production, ozone depletion, and ionizing radiation. The paper advance the state-of-the-art regarding the suitability of red ceramic waste to replace Portland cement for road pavement projects through an integrated approach coupling mechanical, durability, and environmental performance.
