AbstractStructural deterioration is induced by multiple mechanisms due to progressive degradation, such as aging, corrosion, and fatigue, and sudden events, such as earthquakes, tsunamis, and hurricanes. These mechanisms may significantly affect the performance indicators of structural components and systems during their life cycles. Many studies on the effects of structural deterioration on structural performance indicators have been reported in the literature. However, most of them study the effect of a single deterioration mechanism on structural performance indicators in a deterministic context. Therefore, further research is needed to capture the joint effects of multiple deterioration mechanisms on structural performance indicators in a probabilistic context. Moreover, in order to achieve the main goal of infrastructure management by maximizing the life-cycle performance at a minimum cost, an optimal risk-based life-cycle strategy has to be provided. This paper presents a life-cycle risk-based optimal management strategy for bridge networks subjected to corrosion and seismic hazards. The proposed strategy is illustrated with an existing bridge network. Girder replacement is considered for the bridge superstructure, which is prone to corrosion hazard, while seismic retrofit measures are considered for the bridge bearings and substructures to improve their seismic performance. A709-50CR steel girders are used to replace the corroded steel girders herein (A709-50CR is a novel corrosion-resistant steel with a chromium content similar to that of martensitic stainless steel). Parametric analysis is conducted to investigate the effects of both target service life and correlation of the safety margins among the superstructures of the bridge network on the Pareto fronts associated with life-cycle risk-based optimal maintenance solutions. Comparison is also made between Pareto fronts associated with both hazards and those associated with corrosion hazard only.