Proposed Methodology for Obtaining Ballast Layer Performance Indicators

Although ballast layer can be characterized by different parameters, the literature notes the absence of global performance indicators of ballast in service. This article presents a methodology that proposes to obtain local performance indicators (based on the functions performed by the ballast layer) and global performance indicators (based on the combination of the above). The proposed methodology consists of three phases: (i) the first is the performance of a functional analysis (FA) for the identification of the key functions of the ballast layer, (ii) application of the failure mode and effects analysis (FMEA) for the creation of the failure trees of the functions identified in the previous phase, and (iii) application of data aggregation to combine the parameters and indicators in the form of a model to obtain the performance indicators. The results of performance indicators can be useful for the planning of corrective actions and in case of failures or defects to identify their causes. The methodology allows adapting the conditions and/or needs of each railway manager by modifying the failure modes and modifying the scales proposed for data aggregation.