Time-variant performance of composite bridges with protective coating

Abstract

The behaviour of the coating system of composite bridges over time is an important issue as it has significant implications in terms of costs and environmental impacts. However, the estimation of the service life of the bridge and, in particular, of its coating protection usually relies on the information provided by the suppliers and/or experience of the engineers, as life cycle approaches are not yet a daily practice among bridge engineers. The aim of this paper is to assess the time-variant performance of the protective coating of composite bridges and respective impacts. An available simplified tool was adopted in this work, which enables to model the coating degradation of steel bridges and correlate this with the condition of the bridge (or bridge element). However, the available tool has some major disadvantages, since it does not enable the consideration of uncertainties in the main parameters of the model nor the optimization of the strategy leading to the minimization of costs or other constraints. To cope with these limitations, the tool was enhanced by the consideration of an optimization procedure that is able to cope with uncertainties. The advantages of the enhanced tool will be illustrated by a case study.