Structural Reliability Assessment of Post-Weld Treatment Methods for Fatigue Life Extension of Aging Steel Bridges
The management of aging steel bridges poses significant challenges to bridge owners, who must maintain structural integrity under fatigue-induced deterioration while operating within limited maintenance budgets. Although post-weld treatment methods have demonstrated potential to improve fatigue performance, a probabilistic quantification of their comparative reliability benefits remain limited in literature. This study presents a probabilistic S-N based reliability approach to evaluate and compare as-welded condition and three post-weld treatment methods, including burr grinding/TIG, needle/hammer peening, and HFMI. The approach is applied to a welded steel detail under variable amplitude loading, incorporating uncertainties in the fatigue resistance, damage accumulation and stress modelling. The results show that post-weld treatments significantly extend service life. Furthermore, an analysis shows the potential of SHM also contributing to service life extension, however, subjected to a specific outcome probabilities