Fatigue damage assessment of railway steel bridges based on short-term monitoring data

Long-term monitoring for assessment of a structural system generally requires the adoption of solutions with high costs. Alternatively, short-term monitoring, when applied to structures of railway bridges, may be used as tools to characterize the load spectra, since they are samples of the main loads and the confidence levels of models for extrapolation to longer periods. The current load spectra are essential for a better representation of the analysis of fatigue damage, which also depend on the knowledge of accumulated load history. In this context, the objective of the paper is to assess the fatigue damage through S-N curve and linear elastic fracture mechanics (LEFM) based on short-term monitoring data. These assessment methods using in-situ monitoring data were applied to a bridge study case. The annual histograms of the stress are obtained by counting Rainflow method of cycles from acquired time series. Results are presented and the main conclusions validating the applied methodology are presented as well.