9521425 Liapis This research program will investigate the potential effectiveness of flexible inflatable structures as breakwaters. Their geometry, flexibility and damping characteristics would be utilized to reflect or dissipate a significant amount of the wave energy. Two basic cases will be considered: Case I, in which the structure is inflated with air and is moored to the sea bed using tethers, and Case II, in which the structure is filled with water and is anchored directly to the sea bed. The investigation will involve analytical, numerical, and experimental work to study this complex fluid-interaction problem. The effects of many parameters will be examined, such as the wave height and frequency, the structural dimensions and material properties, the internal pressure or head, the tether lengths, orientations, and material properties (for Case I), and the anchoring forces (for Case II). Optimal combinations of the system parameters will be sought, to furnish the most effective wave barrier. ***