Warning Time–Based Framework for Bridge Scour Monitoring

Abstract

To date, various monitoring techniques have been developed to alert authorities of potentially precarious scour depths at bridge foundations. The adoption of such techniques, however, is worthwhile only if sufficient warning time is offered to allow for preventative actions. This is true for any structural health monitoring system. The framework presented in this study is a simple and practical tool for predicting warning times given detected scour depths. The framework incorporates a probabilistic analysis of scour progression such that the uncertainty in warning times can also be determined and used for risk-based decision making. A detailed example was considered for demonstration. The resulting framework is useful in three stages of scour monitoring and management: first, in selecting optimum sensor configurations; second, in encoding the actions required at any detected level of scour depth; and third, in selecting appropriate countermeasures based on warning time.