Comparison construction costs conventional rubblemound breakwaters/bermbreakwater

Given a harbour location and a wave-climate, two different types of rubble-mound breakwaters were designed. Using realistic quarry yield curves and prices for production, transport and constmction, the total costs of the conventional statically stable and dynamically stable bermbreakwater designs were compared to each other. This comparison led to the conclusion that differences in building costs strongly depend on the way the quarry yield is subdivided into different stone classes for both types of breakwaters. In order to satisfy the demand of the heaviest armour stone classes, overproduction for the lighter stone classes is inevitable. The extent of this overproduction had decisive influences in the comparison of total costs. Calculations for different transport distances between quarry and construction site showed only minor differences in the comparison of total costs of both types. The concept of dynamically stable bermbreakwaters appeared to provide great possibilities for considerable reductions of the overproduction in the quarry and the total costs. Realisation of maximum reductions yet requires advanced models for the treatment of the problem of longshore erosion with bermbreakwaters. More extensive research on this topic is recommended.Hydraulic EngineeringCivil Engineering and Geoscience