Proposal of a key performance indicator for railway track based on LCC and rams analyses

The performance of railway tracks can be assessed by separately applying different approaches, such as reliability, availability, maintainability, and safety (RAMS) and lifecycle costing (LCC). Results of these approaches are not comprehensive because RAMS management lacks an LCC perspective and balance, whereas LCC develops an economic analysis but does not address specific issues of railway performance. Based on these considerations, this study defines a key performance indicator (KPI) for railway tracks as merging the LCC and RAMS approaches at a given time. Innovative algorithms are set up for LCC, RAMS, and their relationship in the definition of KPI. Algorithms are applied to two different track alternatives (ballasted and ballastless), and the KPI trend over time is assessed. Case study results show that the KPI of ballasted tracks is higher in the short-term, whereas the slab track performs better in the long-term. The trend of KPI for the two solutions under investigation shows that the breakeven point depends on traffic and speed in the railway lines. The method setup as well the results obtained contribute to the body of knowledge of construction engineering because: (1) the equations set up allow deriving agency-based algorithms through calibration; (2) the model set up and implemented allows agencies to handle basic technical instances (e.g., RAMS) and lifecycle-related issues (in which sustainability is considered) in a synergistic and quantitative way; and (3) the previously mentioned KPI has the potential to quantitatively affect decision making across the entire cycle of life (design, maintenance, and renewal).