Session A.2: Breakwaters (I)

Dr Berguzar Ozbahceci, Izmir Institute of Technology

Have you ever tried a berm or Icelandic breakwater under water?

Reply by S Sigurdarson

One of the main functions of the Icelandic-type berm breakwater is to provide a porous layer above still water level for dissipation of the wave energy. In the early days of berm breakwaters the berm was usually rather low, often about 1 m above the still water level. In theory one could also design such a fully reshaping berm breakwater with a very low or even submerged berm, but this would require a very wide berm and might also give construction problems. The development of the Icelandic-type berm breakwater has been towards higher berms. We now recommend a berm elevation of more than 0.6 *H_s above design water level. On the other hand the Icelandic-type berm breakwater is often designed with a toe berm structure for stability reasons and to reduce reshaping. But for effective dissipation of incoming wave energy and to limit wave overtopping, it is necessary to design the Icelandic-type berm breakwater with an emerging berm.