Bridge failure modes due to local scour

The scour and in particular the local scour induced by flooding events is the predominant cause of bridge collapses and thus severing the related road link with adverse consequences for the road users and the society in general. The widely accepted approach in bridge management to this threat is still lacking. In order to close this gap a vulnerability assessment method is suggested that would allow timely decisions on risk reducing interventions. The vulnerability assessment requires an estimation of the probability of a bridge failure and the corresponding consequences in the scouring event. The bridge failure modes i.e. the way in which the bridge failure unfolds in a scouring event have not been entirely clarified in the literature. The analysis of failure modes allows the identification of necessary parameters and their significance in the vulnerability assessment. The minimum set of these parameters is sought, which allow adequate assessment of bridge vulnerability for management purposes