Updating the reliability of a concrete bridge structure based on condition assessment with uncertainties

This paper investigates if it is possible to obtain information through measurements that permits one to estimate the reliability of a component or system. The technique for condition assessment of a bridge structure with uncertain system parameters from structural acceleration responses with measurement noise is presented. The mean values and the standard deviations of the assessment results are obtained and subsequently included in the reliability analysis of the structure. A three-span continuous prestressed concrete bridge superstructure under the action of a two-axle three-dimensional vehicle is investigated with finite element analysis. The vehicle serves as an exciter whereas the dynamic acceleration responses of the structure are used for the condition assessment with the response sensitivity-based approach. The identified statistical parameters of the bridge structure are shown to be able to give an updated set of safety predictions on the bridge structure.