Design of pattern-placed Revetments

Revetment systems prevent erosion of dikes. The systems need to be stable under wave attack. The size and the weight of revetment elements is the main contribution to their stability. Pattern-placed revetments consist of relatively small blocks or column-shaped natural stones or concrete elements, placed in a regular grid. The pattern creates a regular distribution of joints and voids which limit the build-up of water pressure in the system. The pattern also contributes to the mechanical resistance against wave pressures. When applied on a slope gravity induces a down-slope force in the revetment and provides coherence through frictional interlocking. In this thesis this mechanism is studied in detail with model simulations and field measurements. The contribution of frictional interlocking makes the observed high resistance of pattern-placed revetment structure against concentrated loads comprehensible. This phenomenon can be used in the development of new revetment systems and in optimization of the design of revetment slopes and dikes.