Life-Cycle Cost Analysis of Bridges and Tunnels

This paper presents an analysis of life cycle costs for four bridges and two tunnels constructed and operated by the Port Authority of New York and New Jersey. Cost components include the initial cost, repair and rehabilitation costs, and annual maintenance costs. Results show that the maintenance and rehabilitation costs, as a percentage of the initial cost, are reasonably similar for both bridges and tunnels for perhaps the first 65 years of their service life, after which these costs increase significantly for bridges. However, based on cost per square foot and cost per traffic lane, the opposite is clearly true. Only time and detailed cost records for ensuing years will reveal how the two types of structure compare over their entire service lives.