Swapping crushed rock for stabilized soil cuts railway construction emissions and costs
A Swedish study comparing two railway embankment methods found that using cement-stabilized soil instead of crushed bedrock reduces both climate impact and project costs. The finding suggests infrastructure planners routinely miss savings opportunities by defaulting to conventional materials without sustainability assessment.
Originaltitel: Assessment of climate impact and costs comparing two railway embankment fill methods
<p>Emissions from infrastructure projects and construction projects have a large impact on the environment. Construction activities and materials, including geotechnical engineering works, account for a great share of that impact and the monetary costs of the projects. In railway projects, crushed bedrock is often used as fill material in the embankments, and less suitable soil is excavated and transported to a landfill causing emissions. Despite that, sustainability assessments are rarely made when comparing the crushed bedrock fill method with other alternative methods, when the geotechnical engineer is designing an embankment. This paper, therefore, shows how climate impact and monetary costs can be compared for two fill methods in a railway embankment in Sweden, namely crushed rock fill and fill made of cement-stabilized sandy till. A comparing life cycle assessment (LCA) of climate impact and a life cycle cost analysis (LCCA) of monetary costs were made for the two methods. Activities and materials used in the production and construction stages were assessed. The results show that the stabilized sandy till method had both a smaller climate impact and lower life cycle cost (LCC) than the crushed bedrock fill method. </p>