Analytical and Numerical Models of the RIBS XM99 Ocean-Scale Prototype

Abstract

Abstract : This report describes analytical and numerical modeling efforts to quantify the performance and response of a new type of Rapidly Installed Breakwater System (RIBS) being developed at the U.S. Army Engineer Research and Development Center's (ERDC) Coastal and Hydraulics Center (CHL). The RIBS is a floating breakwater with two legs in a 'V', shape in plain view which provide a sheltered region from waves and currents. The RIBS concept was initially developed to address problems encountered by military personnel during Logistics-Over-The-Shore (LOTS) operations. The primary problem occurs during these operations when sea states become elevated and negatively impact crews trying to discharge cargo and equipment onto smaller vessels from Tactical Auxiliary Crane Ships (TACS) and roll-on/roll-off (RO/RO) vessels. The performance of a floating breakwater can be quantified by the wave transmission coefficient. The structural response can be estimated using the wave-induced dynamic pressures along the structure. These pressures can be used to calculate the wave forces and moments. Preliminary results from the RIBS field study at Cape Canaveral, FL, May 1999, are presented and compared to analytical and numerical models of the RIBS wave transmission coefficient and dynamic wave pressures.