Modeling Infrastructure Performance and User Costs

Abstract

An infrastructure-performance-deterioration model predicts the performance of infrastructure facilities such as bridges, railroad, and highways as a function of explanatory variables such as inherent infrastructure characteristics (material properties, construction quality), ambient climate, usage of the facility, etc. However, there is no unambiguous approach to measuring directly the performance of the facility, and hence we consider performance to be unobservable (latent). The problem of developing performance-deterioration models includes the definition of the aforementioned unobservable performance in terms of the measurable distress measures of the facility, and simultaneously relating the performance to the explanatory variables. In this paper, we extend previous research to include user costs (costs accruing to the users of the infrastructure facility) in the modeling framework. Hence, an integrated performance and user-cost model system is developed, and a case study is conducted on a highway example using data from Brazil compiled by the World Bank. Although, the case study is on highways, the methodology is general and applicable to any deteriorating facility with measurable distress measures and explanatory variables.