Experimental Investigation of Wave Attenuation through Flexible Plants on a Flat Bed.

Plants can serve as a good form of coastal protection against wave wash. A series of physical experiments was conducted with various flexible plant arrangements under regular wave parameters, and the composite wave heights were measured both ahead of and behind the plants. Goda's method was used to resolve incident and reflected waves from the composite waves, from which the wave transmission coefficient and the dissipated energy ratio were obtained. It was observed that the wave transmission coefficient decreased with increasing relative number of plant rows, increasing relative density of plants, and increasing relative wave height and wave steepness. The wave transmission coefficient increased with an increasing wave period T < 2.00 s; however, it decreased with an increasing wave period T ≥ 2.00 s. In contrast, the dissipated energy ratio was disproportionate to the wave transmission coefficient. Dimensional analysis and the least squares method were used to obtain the wave transmission coefficient and the dissipated energy ratio formulas, and they agreed well with the experimental data. This study provided insight into plant revetment engineering at the coastal zone. [ABSTRACT FROM AUTHOR]