Implication of bridge resilience design and lessons from negative examples

Abstract

AbstractBridge resilience is a newly proposed bridge design criterion that involves robustness, redundancy and reparability targeting on the rapidity of functionality restoration after suffering extreme actions and long-term durability deterioration. It stipulates a lower probability of reaching the ultimate limit state or strength limit state, which have been only partly involved in bridge design codes around the world. In AASHTO LRFD Bridge Design Specifications and Eurocodes, there are some design principles related to bridge resilience. Yet, it is also necessary to give more requirements for structural ductility and collapse resistance when the actual load exceeds the load combination in the code. This paper focuses on the resilience-based principles for bridge design, and exposes some problematic bridge structural systems and details, such as bridges most likely to overturning, steel bridges with fracture critical members, arch bridges with suspended desk, Morandi cable-stayed bridges, poor details for seismic vulnerability, etc. Whereas overturning is one of the worst anti-resilience scenarios, the resilience design against bridge overturning is highlighted through a detailed discussion including the calculation methods of anti-overturning factor, overturning stability of curved bridges, reasonable disposition of supports, and anti-overturning countermeasures.