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Source: https://erdc-library.erdc.dren.mil/jspui/ A series of wave tank tests was conducted at the U.S . Army Coastal Engineering Research Center (CERC) to determine the ability of a field of low specific gravity artificial seaweed to attenuate wave action. Wave gages were located on both sides of the seaweed field to measure wave attenuation. The field consisted of seven rows of seaweed with the rows spaced 3 meters (10 feet ) apart. Ten distinct wave conditions were tested using periods ranging from 2.6 to 8.2 seconds and wave heights from 0.24 to 1.1 meters (0.8 to 3.6 f eet). The stillwater depth f or all tests was 2.4 meters (8 feet). There was a measurable level of wave attenuation for only the shortest period, 2.6 seconds. For the 2.6-second period, the reduction in wave height on passing through the seaweed field was about 12 percent.

Source: https://erdc-library.erdc.dren.mil/jspui/ These Proceedings provide a record of the papers presented a t the Floating T i r e Breakwater Workshop conducted on 8-9 November 1984 i n Niagara Falls , New York. Topics of discussion included fieldresearch efforts, basic design considerations, breakwater perf omLance and maintenance, and alternative fastening and mooring techniques. The Workshop was cosponsored by the Coastal Engineering Research Center of the US Army Engineer Waterways Experiment Station and the Canadian National Water Research Institute.

Source: https://erdc-library.erdc.dren.mil/jspui/ A theoretical model for predicting the dynamic behavior of a floating break water is presented along with a report on a field experiment designed to provide basic data for verifying the model. Additional data were taken from the literature and from auxiliary' laboratory experiments. The dynamic behavior characteristics investigated were: (a) Total transmitted and reflected waves and their components; (b) wave forces on the breakwater; (c) motions of the breakwater and (d) forces on the mooring lines. The prediction model was developed from two-dimensional, linearized solutions of the hydrodynamical equations formulated in terms of a boundary value problem for the velocity potential. Some nonlinear effects are considered. Results for the predicted transmission coefficients were in good agreement with laboratory and field data, and they showed how the influence of fixed-body transmission, and of sway, heave, and roll motions on the transmission coefficient changed with increasing values of the parameter, beam (width) to wavelength ratio. The shape of the curves predicting the mooring line forces as a function of the beam (width) to wavelength ratio (or of wave frequency) followed those for the measured responses, but predicted magnitudes did not agree closely with measured values. The floating breakwater at Friday Harbor, Washington, was used as the field experimental platform; it was instrumented to record the incident and transmitted waves, mooring line forces, and the acceleration components of sway, heave, and roll. Ninety-five 17-minute records were obtained during the period 30 December 1974 to 5 May 1975. Statistical summaries of all data-are presented with analyses of selected transmitted waves, transmission coefficients, and acceleration components. The summaries and analyses constitute a performance report of a particular floating breakwater as well as an input to the development of the theoretical model.