Fatigue Life Evaluation of Critical Details of the Hercilio Luz Suspension Bridge

Fatigue assessment of existing bridges is increasingly prominent due to the advanced age and larger traffic demands. The Hercilio Luz Bridge (HLB), which was built in 1926, was closed to traffic in 1991 due to high corrosion levels and deterioration of critical structural elements. A complete rehabilitation project was developed for the bridge which included the replacement of the compromised members and strengthening of the foundations. In this paper, a fatigue life evaluation was carried out using fatigue load models 3 of the Eurocode EN 1991-2 to obtain the calculated stress ranges for the critical members of the bridge, as well as the simplified equivalent stress range and fatigue damage accumulation method for the fatigue safety verification defined by Eurocode EN 1993-2 and Eurocode EN 1993-1-9. Fatigue provisions, such as such truck geometry, S-N curves, fatigue category, etc., are reviewed. The evaluation results reveals that the stringer-to-floor-beam connections near the transition point of the eyebar chain are susceptible to fatigue damage. Besides, the number of cycles caused by a single truck prescribed in Eurocode is conservative. (C) 2017 The Authors. Published by Elsevier B.V.