Design Considerations of Berm Breakwaters

The paper describes the ongoing development of design philosophy of stable berm breakwaters, which aims at minimum movement of armour rocks on the berm, taking into account the armour rock quality. The general method for designing an Icelandic type berm breakwater is to tailor-make the structure around design wave load, possible quarry yield, available equipment and required functions. The present authors design many breakwaters each year and for low design wave height, Hs< 2.5 to 3 m, usually conventional design is chosen, but berm breakwaters for heigher wave heights. The availability of large rock is examined with the aim of finding a quarry giving over 15 to 20% of produced rock with stability parameter, Ho, below 3.0.