Flatiron Dragados
20 - 25 Feb 2026
Fatigue Limit States – Steel Superstructures
Estimated Time: 2–3 min | Difficulty: Intermediate
Question
In a high truck-volume corridor (high ADTT) and a design life of 100 years, which limit state(s) is most likely to control tension flange thickness in a composite steel plate girder bridge?
Explanation:
In high-cycle traffic corridors over a long service life, repetitive stress ranges often govern before ultimate strength is reached. Even when factored resistance is adequate, fatigue stress range may control flange thickness to prevent crack initiation over the bridge’s service life.
Learning Resources: