Hydrodynamic performance of concave front pile-supported breakwaters integrated with a louver wave screen

Abstract

Pile supported breakwaters for water depths greater than 20 m are environmentally friendly and are more economical than the rubble mound breakwaters. An experimental investigation is carried out to explore the hydrodynamic performance of two different concave front pile-supported breakwaters integrated with a louver wave screen (LWS) on their seaside. The LWS consists of an array of plates inclined at 60° to the horizontal and mounted one above the other with spacing such that the porosity is 25%. The breakwater models are subjected to the action of regular waves in a wave flume covering intermediate to deep-water conditions. It is found while, the wave transmission past the breakwaters in presence of LWS is not significantly altered, the reflection from the structure significantly reduces, the rate of reduction being higher for the model with a steeper slope. The study also shows a reduction in the wave run-up and induced pressures over the concave profiles in the presence of LWS. The usefulness of wave screens in improving the performance of a breakwater depends on the breakwater profile in addition to the type of the wave screen which is the main finding of the study.