Assessing the Environmental and Circularity Performance of Conventional and Recycled Materials in Ballasted Railway Track Systems

Railway infrastructure management is increasingly challenged by growing traffic demand, aging assets, and the urgent need to reduce the environmental footprint. In this context, the adoption of circular economy principles and low-impact materials has emerged as a key strategy for enhancing the sustainability of railway infrastructure throughout its life cycle.

This study assesses the environmental performance and circularity potential of ballasted track systems through the combined application of Life Cycle Assessment (LCA) and circularity indicators. A conventional track configuration based on virgin materials is compared with an alternative solution incorporating recycled materials, with the aim of quantifying the environmental and resource-efficiency benefits associated with the adoption of circular material strategies. The results demonstrate that the recycled-material configuration outperforms the conventional solution across multiple environmental impact categories, achieving a 15% reduction in greenhouse gas emissions. These improvements are primarily driven by the reduced extraction of virgin raw materials and the valorization of industrial by-products, highlighting the potential of recycled materials to support more sustainable railway construction practices.

To evaluate the robustness of the findings, a sensitivity analysis was performed considering different recycling and transportation scenarios. The results reveal that transport distances and processing requirements are key factors influencing the overall environmental performance of recycled materials, identifying the conditions under which circular solutions provide the greatest environmental benefits.

Furthermore, the Circularity Index (CI) was calculated to quantify the degree of circularity achieved by each track configuration. The outcomes confirm that the incorporation of recycled materials not only reduces environmental burdens but also promotes the transition from a linear resource consumption model toward a more circular, resource-efficient, and sustainable railway infrastructure system.

The proposed integrated framework provides a practical decision-support approach for infrastructure managers and designers, supporting the adoption of circular economy strategies and more sustainable material selection in railway engineering.