Runup&Rundown Characteristics - Emerged Quarter-Circle Breakwater

Quarter circle breakwater (QBW) is developed from semicircular breakwater (SBW) and the first model was developed in Peoples Republic of China. The superstructure of QBW consists of a quarter circular front wall facing incident waves, a horizontal base slab and a vertical rear wall placed on rubble mound foundation. A series of experiments were conducted in a two dimensional regular wave flume available in Marine structures laboratory of Department of Applied Mechanics and Hydraulics of National Institute of Technology, Surathkal, Karnataka to assess the wave run-up and wave rundown characteristics of an emerged seaside perforated quarter circle breakwater. Quarter-circle breakwater models with three different radii and S/D (spacing to diameter of perforations) ratio were tested. The runup depends on many dimensionless parameters including the seaward slope angle, wave steepness, depth of toe, slope roughness and permeability. Understanding the effect of various sea state and structural parameters is essential in knowing the behavior of the structure and design an optimized structure which is safe as well as economical for the wave conditions considered.