Advance in wave reflection estimation for rubble mound breakwaters: the importance of the relative water depth

In 2008 the authors verified the hydraulic stability of a coastal defense project to be built along the NW coast of Sicily (Italy, Tomasicchio et al., 2009). The intervention consisted of shore parallel barriers armored with a relatively new eco-friendly system: ECOPODETM. In that context the idea arose of conducting an exhaustive experimental campaign on the “ hydraulic response “ of these units, including wave run-up , wave overtopping, wave transmission and wave reflection observations. The latter has been performed in 2010 at the LInC Laboratory of University of Naples “Federico II”. In this paper results on wave run-up and reflection are presented and discussed.

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STUDY OF RAPID SEDIMENTATION AT PARESAR INTAKE BASIN, CASPIAN SEA, DUE TO LARGE WRACK PARTICLES AND WIND-INDUCED CURRENTS

Coastal Engineering Proceedings ◽

10.9753/icce.v36v.papers.4 ◽

2020 ◽

pp. 4

Author(s):

Mina Rashvand ◽

Mohsen Soltanpour ◽

Amir Masoud Moattar Kharrazi

Keyword(s):

Numerical Modeling ◽

Sediment Transport ◽

Water Depth ◽

Caspian Sea ◽

Field Measurements ◽

Longshore Sediment Transport ◽

Major Increase ◽

Induced Currents ◽

Rubble Mound ◽

Rubble Mound Breakwaters

The rapid sedimentation at the entrance of Paresar intake basin is studied, in which unnatural wrack accumulation at the coast, combined with the existing sand, resulted in a major increase in the actual Longshore Sediment Transport (LST) rate. Considering the volume of updrift fillet at the northwest of main breakwater and the estimated LST rate, the advancement of updrift shoreline was highly unexpected. Sands and vegetative wracks were observed only 3 years after constructing the rubble mound breakwaters, resulting in water depth decrease at the entrance. Employing field measurements and numerical modeling, it is revealed that general wind-induced currents in Caspian Sea, which were ignored in the design, have a small effect on increasing LST rate. The unusual sedimentation can be mainly related to the high percentage of wrack particles at updrift coast.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/UNNnjDHL41k

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Laboratory Measurement of Oblique Irregular Wave Reflection on Rubble-Mound Breakwaters

Coastal Engineering 1994 ◽

10.1061/9780784400890.117 ◽

1995 ◽

Cited By ~ 1

Author(s):

Charles Teisson ◽

Michel Benoit

Keyword(s):

Wave Reflection ◽

Laboratory Measurement ◽

Irregular Wave ◽

Rubble Mound ◽

Rubble Mound Breakwaters

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Investigation on the Reflection Coefficient for Seawalls Protected by a Rubble Mound Structure

Journal of Marine Science and Engineering ◽

10.3390/jmse9090937 ◽

2021 ◽

Vol 9 (9) ◽

pp. 937

Author(s):

Luigi Pratola ◽

Antonio Rinaldi ◽

Matteo Gianluca Molfetta ◽

Maria Francesca Bruno ◽

Davide Pasquali ◽

...

Keyword(s):

Reflection Coefficient ◽

Wave Reflection ◽

Experimental Tests ◽

Coastal Protection ◽

Empirical Formulas ◽

New Approach ◽

Wave Flume ◽

Mound Structure ◽

Rubble Mound ◽

Rubble Mound Breakwaters

Sea wave reflection from coastal protection structures is one of the main issues in the coastal design process. Several empirical formulas have been proposed so far to predict reflection coefficient from rubble mound breakwaters and smooth slopes. The aim of this study is to investigate wave reflection from a rubble mound structure placed in front of a vertical concrete seawall. Several experimental tests were performed on a two-dimensional wave flume by reproducing on a rubble mound structure with a steep single primary layer armored with a novel artificial unit. A new approach for the prediction of the reflection coefficient based on dimensional analysis is also proposed, and a new empirical equation is derived. The performance of the proposed equation was compared with widespread existing formulas, and a good accuracy was found.

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Reflection Analysis of Impermeable Slopes under Bimodal Sea Conditions

Journal of Marine Science and Engineering ◽

10.3390/jmse8020133 ◽

2020 ◽

Vol 8 (2) ◽

pp. 133

Author(s):

Stephen Orimoloye ◽

Harshinie Karunarathna ◽

Dominic E. Reeve

Keyword(s):

Reflection Coefficient ◽

Water Depth ◽

Wave Reflection ◽

Experimental Tests ◽

Random Wave ◽

Reflection Coefficients ◽

Wave Steepness ◽

Coastal Structures ◽

Relative Water ◽

Reflection Characteristics

Understanding of the reflection characteristics of coastal seawalls is crucial for design. Wave reflection can cause difficulties in small vessel manoeuvring at harbour entrances; this can cause damage to the toe of coastal structures by scouring. Previous studies have examined the reflection characteristics of coastal seawalls under random wind-generated waves without considering the effects of wave bimodality created by the presence of swell waves. This present study focuses on the influence of random wave bimodality on the reflective characteristics of coastal seawalls. 823 experimental tests were conducted to examine the reflection performance of impermeable sloping seawalls under bimodal waves. Reflection coefficients were computed from each test. The analysis of the results suggests that both unimodal and bimodal waves give similar reflection characteristics. However, the reflection coefficient in bimodal sea states seems to be more prolonged than in the unimodal sea states. It was found that the reflection coefficients of coastal seawalls are strongly influenced by the seawall slope, the wave steepness, the relative water depth, and the surf similarity parameters. A new empirical reflection equation to describe the influence of wave bimodality on the reflection characteristics of coastal seawalls has been formulated based on this study.

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