ABSTRACT
Bridges, as an important component of infrastructure, are expected to have a long service life and high safety margin, but these requirements often entail an increase in the life-cycle cost. In this paper, several optimal designs of continuous post-tensioned concrete box-girder road bridges, considering initial cost, durability and structural safety as objectives, are obtained first. These bridges are subjected to chloride attacks in coastal environment. Then, a lifetime-reliability-based approach is used to evaluate the maintenance required to satisfy a reliability target during a specified time horizon. The differences among these designs would lead to alternative maintenance options. These maintenance options would in turn affect the life-cycle cost of bridges, which includes the bridge initial cost and the maintenance cost. The results provide the designers with different options from a life-cycle perspective in the early design stage.
