Seepage in a flood protection dam – first centrifuge test results

Many flood protection dams in Europe were built more than 100 years ago. These dams often do not meet current flood protection requirements due to increased level of safety requirements, higher damage potential in the valley plains and due to higher peak discharges or water levels expected with changing climatic conditions. A first series of centrifuge tests on an idealized cross-section of a flood protection dam has been carried out in the geotechnical centrifuge at TU Delft in order to study the seepage behaviour of a horizontally layered dam consisting of layers with coarse and fine-grained material. Main aspects of the testing equipment such as a specially manufactured test box which allows to simulate certain flood events of different durations and intensities are presented. Furthermore, measured values of the pore pressure during the investigated flood event, are presented and discussed in comparison to the results of finite element modelling of the dam. Finally, the influence of the hydraulic boundary conditions on the seepage behaviour in the physical and numerical modelling is critically discussed.