Wave‐Induced Forces on Armor Unit on Berm Breakwaters
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 120, Issue 3
Abstract
Wave‐induced parallel and normal forces on an armor unit on a berm breakwater have been measured. The armor unit was located on the flattened part of the reshaped berm breakwater. Simultaneously with the force measurements water‐particle velocities in the vicinity of the armor unit have been measured with a laser Doppler velocimeter. The parallel forces have been analyzed as a Morison‐type force. Drag coefficient and inertia coefficients were obtained by a least‐square method. The average value of was approximately 0.35 and of approximately 0.2. The wave forces on an armor unit at the location of the measurements are drag dominated. Hence the data are best conditioned for obtaining values and not so well conditioned by obtaining values. We believe that this is a major reason for the low values, since normally the values should be larger than 1.0. An unsuccessful attempt has been made to model the normal forces.
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Information & Authors
Information
Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 120 • Issue 3 • May 1994
Pages: 251 - 268
Copyright
Copyright © 1994 American Society of Civil Engineers.
History
Received: Feb 1, 1993
Published online: May 1, 1994
Published in print: May 1994
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