Marinella Giunta, Mohammed Er Rouisse
This study evaluates and compares the technical and environmental performance of three innovative and sustainable railway sleeper materials: geopolymer concrete (GC), acetylated wood (AW), and recycled polymer with steel inserts (RP). The evaluation combines a technical performance assessment with a Life Cycle Assessment (LCA) based on the ReCiPe 2016 method, applied at both midpoint and endpoint levels. Key midpoint indicators include climate change, human toxicity, freshwater and terrestrial ecotoxicity, fossil and mineral resource scarcity, and land use, while endpoint indicators assess impacts on human health, ecosystem quality, and resource availability. The findings reveal clear trade-offs among the alternatives when compared to traditional concrete sleepers (CS). GC sleepers, produced with industrial by-products and reinforced with steel, achieve reductions of approximatively 10–20% in key impact categories such as global warming potential, human toxicity, and resource depletion, indicating a more balanced environmental profile. AW sleepers, although derived from renewable sources, are negatively affected by the energy-intensive acetylation process, resulting in a 35% increase in Global Warming Potential (GWP). RP sleepers, made from recycled plastics, demonstrate the lowest overall environmental impacts, achieving up to 50% reductions in GWP and toxicity indicators. Endpoint results support these trends, with RP sleepers delivering approximately 80% lower resource depletion, around 50% reduction in ecosystem damage, and over 40% improvement in human health indicators, positioning them as the most sustainable option among those assessed. This study offers valuable insights into the environmental and technical performance of emerging sleeper materials and highlights the importance of adopting integrated, multi-criteria approaches, encompassing both midpoint and endpoint indicators, to guide material selection in line with circular economy principles and long-term sustainability goals. • Technical and environmental performance of innovative railway sleepers is assessed using LCA (ReCiPe 2016, Midpoint and Endpoint). • Geopolymer concrete sleepers reduce greenhouse gas emissions and fossil energy use but have high toxicity and mineral resource demand. • Acetylated wood sleepers show low human toxicity and efficient resource use, yet their acetylation process increases energy consumption and emissions. • Recycled polymer sleepers enhance waste valorization and raw material savings, while steel inserts raise impacts on resource depletion and toxicity. • The work highlights the potential role of multi-criteria decision-making in guiding sustainable material selection aligned with circular economy principles.