Comparison of Homogenous and Multi-layered Berm Breakwaters with Respect to Overtopping and Front Slope Stability

A model test study was conducted to study overtopping and front slope stability of homogenous and multi-layered berm breakwaters. The two breakwater types are compared and cons and pros are listed. The study shows that the optimum number of stone classes might be significantly lower than what has previously been used in the Icelandic type of berm breakwater because it seems that the number of stone classes in the berm can be reduced from five to two without significantly influencing overtopping and stability performance. Moreover, the new results are compared to the design formulae established for homogenous berm breakwaters by Lykke Andersen (2006).A model test study was conducted to study overtopping and front slope stability of homogenous and multi-layered berm breakwaters. The two breakwater types are compared and cons and pros are listed. The study shows that the optimum number of stone classes might be significantly lower than what has previously been used in the Icelandic type of berm breakwater because it seems that the number of stone classes in the berm can be reduced from five to two without significantly influencing overtopping and stability performance. Moreover, the new results are compared to the design formulae established for homogenous berm breakwaters by Lykke Andersen (2006)