LATEST DEVELOPMENT IN BERM BREAKWATERS, THE ICELANDIC TYPE

Berm breakwaters have been designed and constructed in Iceland since 1983. Over twenty rubble mound structures of the berm type have been constructed so far, fourteen were new structures, whereas the remaining six were improvements or repairs of existing breakwaters. During 1998 two berm breakwaters are being extended. Further two structures will be built every year for the next 2-3 years. Although some of the berm structures in Iceland have already experienced the design or near to design wave conditions, only minor profile changes have been observed. Valuable experience has, however, been learned from the inspection of the reshaped profile of one structure. The initial idea of berm breakwater, was that it was a wide voluminous structures built of two stone classes and with a wide gradation. The Icelandic type of berm breakwaters has developed into a less voluminous, more stable structure, where large emphasis is put on maximising the outcome of the armour stone quarry and utilising it in the design.