ABSTRACT
The total costs of a highway bridge project consist of project direct costs and added work zone-related user costs during project execution. The impacts of traffic demand shift may occur for highway segments within the physical range of the bridge preservation project and outside of the project physical range. The investment in a highway bridge may lead to decreases in bridge life-cycle agency costs and instigate savings of life-cycle user costs. In the analysis process, the overall project-level user benefits resulting from bridge facility service life change and traffic demand shift can be addressed simultaneously in annual user cost calculation and be extrapolated to one bridge service life cycle. The difference in life-cycle agency and user costs in perpetuity between the base case and an alternative case defines the overall project-level agency and user benefits in perpetuity.
