A Bayesian belief network model of bridge deterioration

Abstract

Bridge deterioration is a major component in making bridge management decisions. It is obvious that the deterioration of one bridge element may accelerate the overall deterioration of a bridge. Current studies, although very promising, fail to address interaction among bridge elements in an effective manner. Fault tree modelling has been advocated as one of the methods that effectively handle the issue of bridge element interaction. Fault tree analysis, however, is well suited for catastrophic failure, which is uncommon in bridge deterioration. As an alternative to fault trees, belief networks are more appropriate for modelling the long-term deterioration that is typically characteristic of bridges. This paper develops a new deterioration modelling procedure based on belief networks. Belief networks effectively capture and illustrate the hierarchical, interaction, and uncertainty factors present in the bridge deterioration process. An example belief network deterioration model is presented and used to address ‘what if’ issues that are characteristic of any bridge maintenance and management process.