Citation

Akgul F, Frangopol D. Transp. Res. Circular 2003; (E-C049): 323-334.

Copyright

(Copyright © 2003, U.S. National Academy of Sciences Transportation Research Board)

DOI

unavailable

PMID

unavailable

Abstract

A probabilistic framework forecasting the lifetime safety and serviceability of a network of highway bridges located along U.S. Highway 36 in Colorado is presented. In addition to performing a live load rating analysis for each bridge, performance functions defining the failure conditions for superstructure components are derived, in terms of both the ultimate strength and the serviceability limit states, using load and capacity requirements defined by AASHTO specifications. The performance functions are established by grouping the random variables and constant parameters in such a way that the formulas are applicable to any type of bridge having similar superstructure components. Thus, the developed performance functions are applicable to other similar bridges, which creates the possibility of evaluating a larger number of bridges in a wider network area, such as a transportation region within the state of Colorado. Using the developed performance functions, initial reliability indices have been determined for the components of the selected highway bridges. By defining the potential failure of the superstructure through a system model, a system reliability index is calculated for each bridge. Resulting component and system reliability indices are compared with the corresponding load ratings of the bridges. A time-varying truckload model and a material degradation model are used to determine the reliability indices of each bridge component and system over the bridge's lifetime. Both safety and serviceability of each bridge are observed over its lifetime based on the predicted load increase and strength reduction. The resulting reliability profiles form the basis for a network-level management planning study for a group of similar bridges that is based on structural reliability.