Service Life Estimation of Concrete Bridge Decks

As existing bridges continue to deteriorate, the Korean Ministry of Construction and Technology (MOCT) including each State Department of Transportation (DOT) in the U.S. faces increasing demands on the limited funds available for bridge maintenance. In such circumstances, highway bridge owners need realistic and effective deterioration models to find the deterioration rate for present and future condition of the bridge deck and to estimate the end of service life of the bridge. The MOCT recently make it mandat ory that life cycle cost analysis (LCCA) for value engineering be used to all government, construction projects including private se ctor projects over 10billion won in terms of Korean currency., In the LCCA concept, it is important to estimate the end of service li fe of the bridge. Several models are available to predict the deterioration rates of bridge main structure such as deck, superstructu re, and substructure. This paper presents a new model that predicts the end of service life in concrete bridge decks based on (i) the deterioration rate and (ii) the condition rating for decommissioning. This paper proposes the deterioration models of concrete bridge decks for 30 DOTs. The data required for developing the models was obtained from the National Bridge Inventory (NBI) database. Whereas, the additional data required for this research were collected through a questionnaire survey. Statistical linear regre ssion method was used to analyze the deterioration models of concrete, bridge decks for each DOT.