Determination of Wave Transmission Coefficients for Oyster Shell Bag Breakwaters

Problems are inevitable in the use of oyster shell bag breakwaters. Oyster shell bag breakwaters have been used in many locations throughout the USA to quantify their ecological benefits, but little research has been conducted regarding their wave attenuating properties. Quantitative information has been produced for traditional structures, but nothing has been published to describe the attenuating properties of an oyster shell bag breakwater. Currently, projects employing oyster shell bag breakwaters would need to adopt published methodologies for determining the transmissive properties of traditional materials or conduct individualized experimentation for their project to determine the adequate dimensions necessary to handle the hydrodynamic loads applied to them. Projects using this methodology could over design or under design the oyster shell bag breakwaters. The objective is to resolve this issue by conducting laboratory experiments in a controlled setting and comparing those results to existing methodologies available in the published literature. The results obtained in this report are a substantial finding in terms of constructing oyster shell bag breakwaters. The data obtained from testing is compared to published methodologies for measuring the wave transmission coefficient of low crested breakwaters (Van der Meer et al., 2005), which produces a distinguishable resemblance based on the 43 tests conducted during this study. However, additional testing should be conducted to enhance the initial findings by including practical application variables such as wave variability and structure placement in relation to the shoreline.