Cost-analysis-based decision-making methods and processes for bridges

This paper presents in-depth studies on the engineering background, techniques and processes of the cost-analysis-based decision theory for bridges. Characteristics of decision making problems in bridge engineering practices show that most of them are dynamic risk-type multiple-attribute decision-making (MADM) problems. Cost analysis-based decision-making techniques for bridge engineering are summarized in this study. The MADM theory is then systematically integrated into bridge engineering decision making, and a cost analysis-based MADM method is proposed, specifically for strategic decision problems in bridge constructions. The key principles behind this method are the simplification of risk-type MADM problems into deterministic MADM problems, calculation of the time weights and the attribute values through the cost-analysis method, weighing of the incommensurable and contradictory objectives through decision matrix standardizations and rational weight coefficients assignment, and sensitivity analysis performed to examine decision stability. The MADM method is then adopted to solve a strategic decision problem of bridge type selection. The results show the potential of the proposed cost-analysis-based decision-making method for application in specific bridge engineering decision problems.