Acceptance of Corrosion-Resistant Steel in Design of Steel Girder Bridges Based on Expected Utility Theory

In a chloride-containing environment, steel bridges that use carbon steel can become corroded and require periodical inspection, repainting, and replacement to maintain an acceptable level of safety and serviceability during their service life. In recent years, several new bridges in the United States have adopted corrosion-resistant steels (i.e., ASTM A1010). Although corrosion-resistant steel can result in a substantial reduction in maintenance costs, its production cost is much higher than carbon steel. From a life-cycle cost perspective, the circumstances under which corrosion-resistant steel is economically advantageous remain unclear. The life-cycle costs that account for the uncertainties associated with traffic loads, including resistance, corrosion propagation, and maintenance activities further complicate this problem. The objective of this paper is to investigate the acceptance of corrosion-resistant steel in the design of steel girder bridges based on expected utility theory (EUT). The methodology developed will be exemplified on a steel girder bridge. Two types of utility functions will be used to characterize the preference of decision makers under uncertain conditions. The analysis results indicate that A1010 is the preferred solution for bridges in aggressive environments, or with severe failure consequences, or both, when the discount rate is low.