In the current era of greater stakeholder participation, limited funding, and increased user awareness, bridgemanagers are turning to the use of multiple-criteria techniques in their decision-making processes so thattheir decisions can be more accountable and transparent. However, issues that arise in solving such decisionproblems include the multiplicity of the performance criteria and associated decision constraints, and thelarge size of bridge inventories in most states. These translate into increased problem dimensionality, largenumber of variables, and ultimately, excessive computational time.This paper presents alternative problem formulations and solution methods for the decision problem,identifies alternative algorithms for implementing the solution methods, and evaluates the performance of thealgorithms. The algorithms included the Incremental Utility Cost (IUC), Lagrangian Relaxation, and Pivotand Complement methods. In investigating the suitability of these algorithms for agency-wide bridgemanagement, the study carried out computational experiments using field data. The criteria for evaluating theperformance of the algorithms were computational speed, accuracy, simplicity, and robustness.The results were unequivocal: Of the three heuristics, the IUC heuristic consistently yielded the bestperformance. It was also seen that the IUC method provides the simplest and quickest way to compute theoptimal solution in the case of small changes in the input parameters without the need to re -do the entireoptimization for each budget level.
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