ABSTRACT
ABSTRACT: The historical performance of welded steel bridges in the USA is reviewed with focus on fatigue cracking at welded steel details, as well as distortion induced cracking at web gaps. Also examined is the impact of corrosion loss of section as a contributing time-dependant factor to fatigue resistance. The role of steel materials including modern high performance steels (HPS) is reviewed as is the influence of corrosion. Variable amplitude loading is also examined and compared with current design of steel bridges for fatigue resistance. Also examined are methods to improve and retrofit fatigue sensitive details, including modern post-weld enhancement by ultrasonic impact treatment (UIT).
