Comparing Roadway and Railway Bridge Maintenance: Performance Indicators, Predictive Models and Path to Digitalization

Roadway and railway bridges have different inspection procedures, performance indicators, maintenance strategies and decision processes. This paper compares two methodologies, an inspection and management system for roadway bridges implemented in a Portuguese municipality, and a predictive approach to forecast the degradation in railway systems based on geometric and structural indicators. The comparison identifies the main differences in condition evaluation criteria, indicators and data availability, while highlighting aspects in which both approaches can complement each other to support more consistent assessments. This paper also discusses how inspection data and performance indicators can contribute to risk-aware and reliability-oriented maintenance decisions, particularly when models are capable of being updated as new data becomes available. The differences in availability and source of information between the two assets will also be analyzed. Although the two infrastructures follow distinct operational and inspection contexts, the comparison shows that both can benefit from clearer indicator structures and more systematic use of predictive information. Based on these insights, the paper outlines how structured data flows and models that can be update may create conditions for future digitalization efforts, including workflow improvements that may support the later development of a Digital Twin. The results provide a realistic and technically grounded step toward more informed maintenance strategies for roadway and railway bridges.

Keywords: Roadway bridges, Railway bridges, Performance indicators, Maintenance management, Risk-based prioritization, Reliability, Digitalization.