Evaluation of Expected Utility for Decision Analysis of Structures

In order to make a rational decision about a cost-effective solution the life-cycle cost of a structure including cost of structural failure needs to be considered. Due to uncertainties associated with structural properties, loads and environmental conditions the cost of structural failure is a random variable. The paper derives probability distributions of the cost of failure of a single structure and a group of identical structures when single or multiple failures are possible during the service life of a structure. The probability distributions are based on cumulative probabilities of failure of a single structure over its service life. The probability distributions can be employed to evaluate the expected utility, which is then used in decision making. An example, which considers the selection of durability specifications for a reinforced concrete structure built in marine environments, illustrates the use of the derived probability distributions.