Integrated Design of Sea- and Estuarine Dikes

摘要

The impact of the expected changes in the global climate will create an unknown challenge for coastal protection. The anticipated acceleration of the sea level rise in combination with an expected higher set-up of storm surges will create higher storm surge levels and stronger waves. Existing guidelines for the design of dike heights only consider hydrodynamic loads, whereas the resistance of the dike body or the dike covering has not been part of the design criteria up so far. Therefore, dikes had to be heightened according to the hydrodynamic loads. To achieve an economical and safe design, it is necessary to consider the hydrodynamic loads in more detail, together with the soil mechanic resistance of the dike material. That was the idea behind the integrated design concept developed in the project "Integrated Design of Sea- and Estuarine Dikes" of the German Coastal Engineering Research Council (KFKI), funded by the German Federal Ministry of Education and Research (BMBF). To establish the quantification of the soil mechanic characteristics, a detailed knowledge of the hydrodynamic loads is essential. This cannot be adequately achieved by way of empirical relationships. In order to match such requirements, the mathematical model OTT-Id of HR-Wallingford was developed, validated, calibrated and verified. Implementing the model for design practice, it was extended in such a way, that different roughness sections can be considered and the loads of the inner slope can be quantified. Finally, the integrated design concept is shown for one typical type of dike, for varying load scenarios at the coast and in an estuary of Lower Saxony, respectively.