Full-scale testing of piping prevention measures: three tests at the Ijkdijk

Large scale tests involving dike failure mechanisms and new sensor technology are presented. The tests were run at a test site in The Netherlands. The influence of wave overtopping on a grass dike was tested, two slope stability tests were performed and seven tests on piping carried out. The results indicate that a grass dike is much more resistant to wave overtopping than expected and the usual slip circle calculations result in a sufficiently accurate description of the slope stability for the tested soft soil conditions, but it appeared to be difficult to acquire reliable values for the permeability and strength parameters of peat from element tests. The piping tests are the main focus of this paper. A series of four tests showed that the predicted scale effects also apply on this larger scale, and confirmed the time dependency of the piping process. A second series of three tests showed the efficiency of various piping prevention measures. Apart from the specific results, the advantages and disadvantages of such large scale tests are also discussed.