Bemessungsereignisse für vorübergehende Bau- bzw. Revisionsphasen bei Hochwasserschutzbauwerken

Design events for temporary construction or revision periods of flood protection measures

Flood protections measures in Germany are designed in a way that they can withstand a flooding event with a defined frequency of occurrence. The evaluation of the return period of the design event should include potential damages in the hinterland or the protected area, respectively. However, flood protection structures are usually designed for an estimated operation time between 50 and 100 years. The geotechnical evidence has to be carried out in accordance with European regulations and their national supplements for a reference period of 50 years. But, the realization of the flood protection in terms of temporary construction or revision phases is only mentioned exemplarily as to perform them in seasons in which the likelihood of large floods is less. Here, the question arises about the return period to account for. Hence, the focus is on estimating the probability that a particular event occurs at a specific site during the construction or revision period.
In this paper, we introduce an approach based on the Poisson distribution taking into account the relation between the frequency of occurrence of design events and the construction or revision period as well as the vulnerability of the area to be protected.