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Publish and Present
Shannon Clarke, M.ASCE
Waterfront Engineering
Mott MacDonald
Delray Beach, Florida
Scott Fenical, P.E., M.ASCE
Vice President, Coastal Practice Leader
Mott MacDonald
San Francisco, California
Frank Salcedo, P.E.
Engineer
Mott MacDonald
San Francisco, California
Abhishek Sharma, PhD
Coastal Engineer
Mott MacDonald
San Francisco, California
Gary Ledford, P.E., M.ASCE
Project Director, Ports & Maritime
Jacobs
Cape Canaveral, Florida
William Crowe, P.E., M.ASCE
Senior Director – Facilities, Construction & Engineering
Canaveral Port Authority
Cape Canaveral, Florida
Port facilities experience scour resulting from high-velocity propeller wash directed towards the berth structures, particularly during arrival and departure maneuvers. This scouring action can not only undermine the structural integrity of the structure, but also contribute to variations in the bottom profile, due to deposition of the scoured material in other areas within the berthing or maneuvering basin. To prevent scour, protection systems are installed which are designed to be stable under these large propeller wash forces.
At Cruise Terminal 1 and 3, Port Canaveral, FL, propeller wash velocities were determined using a combination of momentum jet theory to identify initial velocities, and computational fluid dynamics (CFD) modeling to determine the bottom velocity distributions. The initial jet velocity, jet diameter and location of the zones of established flow were calculated from theory and a commercial CFD code was used to determine flow fields, jet interaction with the bulkhead and bottom slopes, and maximum velocities. The CFD modeling was instrumental in providing accurate, spatially varying velocities to be used for design criteria, which were then used to optimize the scour protection system. CFD modeling also provided detailed evaluations of scour for various bulkhead concepts, apparent roughness of the bulkhead walls, mattress height variability, and other elements of the design. Bottom velocities were characterized in terms of their spatial coverage, duration, and likelihood to induce instabilities in scour protection design concepts. Scour protection systems evaluated were 1) multi-layered placed rock, 2) rock filled mattresses/baskets and 3) cast-in-place concrete grout filled mattresses.
This paper provides an overview of a) computational methods used to determine the bottom velocities, b) potential scour protection solutions, c) analysis used to eliminate the rock and basket solutions, d) specific installation requirements of the concrete grout filled mattress, and e) provide construction lessons learned, and describe post-construction performance.