Overview

This historic metallic railway bridge is a critical link in the Swiss network, but is prone to fatigue and limits the speed of crossing trains. Traditionally, its degradation is tracked through load tests at multi-year intervals, measuring deflections at key points by geodetic survey. IRMOS deployed its intelligent monitoring system to track key damage indicators continuously, combined with real-time estimates of fatigue-damage accumulation and predictive scenario tools. Vibration-derived deflections matched the geodetic load tests to within <1% precision, while capturing behaviour the periodic tests cannot. The resulting reduction in uncertainty has allowed BLS to consider raising the speed limit for trains crossing the bridge.