Factors to consider in bridge performance
16/12/2025
When designing a bridge, engineers must consider several key aspects to ensure it meets its intended purpose over time. Three important factors are reliability, availability, and safety.
What should be considered in bridge performance?
Reliability refers to the probability that the bridge remains functional throughout its service life, complementing the chances of structural or operational failure. Availability, on the other hand, is the proportion of time the bridge is operational, taking into account factors such as maintenance works and traffic restrictions. Lastly, safety focuses on minimizing the potential for harm to people during the bridge’s use.
Additionally, when determining how a bridge should behave, two important concepts come into play: robustness and resilience. Robustness is the ability of a structure to withstand extreme events, such as fire, explosions, or human error, without significant damage. Resilience, however, refers to the bridge’s capacity to recover quickly after a disruption, possibly even adapting to new configurations or network structures.
For critical infrastructure, a robust design is essential to prevent disproportionate damage and service disruption, despite the higher costs. In contrast, for non-critical infrastructure, a resilient design might be more cost-effective, allowing temporary service reductions with minimal long-term effects. Balancing these factors ensures that bridges remain functional, safe, and efficient throughout their lifespans.
Consult the ACRP Guide about Inspection and Repair of Bridges if you want to learn more about the principles, tasks, and methods involved in surveying and maintaining bridges and visit the ACRP library.
