Dikes on peat are stronger than previously thought. But it was not yet possible to calculate exactly how strong they are. That situation has changed: on the basis of practical studies consisting of field trials, laboratory experiments and centrifuge tests, Deltares produced an improved calculation and design method for dikes on peat. The method is based on the dikes around the Markermeer Lake but some of the research components can ultimately be used for different dikes on peat. There is also considerable international interest.
Using the improved design method, it is possible to determine the stability of the dikes on the Markermeer Lake, which are located on a peat subsurface. The method describes the entire design process, from the determination of parameters up to and including the design of the dike upgrade. It consists of a total of nine steps, in which CPT (field probe) findings and laboratory experiments were combined with measurement data from the field trials. The improved design method will have immediate consequences for the Hoorn - Amsterdam section of the dike. A better understanding of the strength of the peat could make it possible to reduce costs and take less drastic action. Calculations will be made later this year of the ultimate savings.