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Source: https://erdc-library.erdc.dren.mil/jspui/ ; When major stone structures such as jetties, breakwaters, or groins are erected in the coastal zone, they alter the existing tidal, wave-induced, or wind-driven currents that are in a dynamic equilibrium with the existing bathymetry. These altered currents and waves breaking on such structures under construction may change the existing bathymetry by causing bottom material to be suspended and transported from the region. This removal of material from around structures is often not compensated for by an influx of additional material, and the result is a scour hole that usually develops in the near vicinity of the toe of the partially completed structure. In order to ensure structural stability, any such scour area must be filled with nonerodible material (sufficiently stable to withstand the environmental forces to which it will be subjected) to allow construction to proceed to completion. This may result in significant additional quantities of material being required during construction that can potentially lead to substantial cost overruns. Four fundamentally different materials are presently being used to combat scour from wave-induced erosion around major stone structures. These are: (A.) A layer of crushed or quarry-run stone (graded or ungraded) placed as a foundation blanket on sandy or otherwise semiconsolidated foundations to prevent upward migration of loose materials and settlement of larger stone sizes. (B.) Fabricated gabion units placed underneath stone structures to form a continuous layer in lieu of a crushed stone foundation blanket. (C.) A wide assortment of synthetic filter fabrics placed underneath rock structures to prevent settlement into otherwise unconsolidated foundations. (D.) To a lesser extent, the use of Gobimats, particularly for toe protection of shore-connected structures such as seawalls or slope revetments. The objectives of this research were to develop techniques and knowledge for estimating resulting wave characteristics and ...