WAVE INTERACTION OF THE H-TYPE FLOATING BREAKWATER

Suppression of wave energy has been a challenge to many coastal engineers and researchers. Numerous efforts have been taken in the development of both hard and soft strategies in protecting coastal infrastructures from the intrusion of destructive waves. Breakwater is one of the most widely used structures in offering some degree of protection to the shoreline. Despite excellent wave dampening ability, the fixed breakwaters may pose several drawbacks mostly to the environment, i.e. interruption to sediment transport, interference to fish migration, water pollution and the downcoast erosions. This study aims at developing the H-type floating breakwater in providing an alternative to the bottom-seated breakwaters. A large scale (1:5) test model constructed using plywood and fiberglass coating was extensively tested in a 25-m wave flume equipped with measuring wave probes in its vicinity. Regular and random wave conditions were generated by the wave generator in the flume. Some of the important test parameters were breakwater immersion depth, wave period and wave height. In total, 108 tests were conducted in this study. The hydraulic performance of the H-type floating breakwater was quantified by the coefficients of transmission, reflection and energy loss. In general, the test model is an effective wave attenuator (with wave attenuation up to 95%), strong wave reflector (reflection of 42 - 87% of incident waves) and good energy dissipater (as high as 85%). In comparison with other types of floating breakwater, the H-type floating breakwater outperforms the others in terms of wave attenuation. This indicates that the configuration of the H-shape floating breakwater is effective in enhancing its overall hydraulic performance.