Experimental Investigation of Fluid‐Filled Membrane Breakwaters

Large-scale experiments were conducted on the interaction of water waves and a fluid-filled membrane cylinder. The test results can be used to address the potential effectiveness of fluid-filled membranes as engineering structures. A circular cross section was modeled to compare to the results for a rigid circular cylinder that had a zero reflection coefficient and is not a wave barrier. The circular membrane cylinder did not have a zero reflection coefficient and the transmission and reflection characteristics show a strong period dependence. In particular, the results show that there is a range of wave periods where fluid-filled membranes might serve as an effective breakwater. For the range of excitation periods that the membrane is effective as a wave barrier, the transmitted wave energy is reduced by a combination of rigid-body motion, deformation, and viscous effects. For other excitation periods the membrane performs similar to a rigid cylinder.