Quantifying the Performance Age of highway bridges

In this paper we propose a new parameter called Performance Age and the methodology to quantify it. This parameter provides a solid life cycle performance basis for bridge replacement. It is not only developed to give a new perspective to the replacement decision process, but also to support a strategic network management approach for civil infrastructures. The method draws on the principle that a bridge not necessarily has to be end of life at its estimated technical age, as long as it performs better than its expected use. For a bridge this idea could mean that it can reach a higher age than its assumed design life. We quantify Performance Age concept based on a hierarchical model, which consists of a translation of this expected performance with criteria and indicators. A prototype model was tested for three fixed concrete highway bridges managed by Rijkswaterstaat, an agency of the Dutch Ministry of Infrastructure and Environment. The results of this study show that Performance Age can be a useful parameter to predict the end of life of bridges.