Discussion of “Revisiting Longshore Sediment Transport Formulas” by Saeed Shaeri, Amir Etemad-Shahidi, and Rodger Tomlinson

Analysis of longshore transport at a littoral barrier is presented. Channel Islands Harbor, California was selected as the study site because its offshore breakwater and jetties form a unique complete littoral barrier. Through repetitive surveys an accurate determination of longshore material transport in one direction was made. Measured transport rates ranged from 160,000 to 1,284,000 cubic meters per year. Utilizing visual observations of surf parameters, estimates of longshore wave thrust were computed. The range of wave thrust was 145 to 1,988 Newtons per meter. Comparison of the relation of wave thrust and longshore sediment transport is made. This study indicates that in an environment of high transport, nearly twice as much transport is predicted tinder corresponding wave thrust as that of the data summarized in the Coastal Engineering Research Center's Shore Protection Manual.

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Coastline changes in relation to longshore sediment transport and human impact, along the shoreline of Kato Achaia (NW Peloponnese, Greece)

Mediterranean Marine Science ◽

10.12681/mms.271 ◽

2001 ◽

Vol 2 (1) ◽

pp. 5 ◽

Cited By ~ 9

Author(s):

S. POULOS ◽

G. CHRONIS

Keyword(s):

Sediment Transport ◽

Human Activities ◽

Dynamic Equilibrium ◽

Littoral Drift ◽

Coastal System ◽

Longshore Sediment Transport ◽

Longshore Drift ◽

Management Plans ◽

Natural Equilibrium ◽

Oblique Approach

Coastal configuration depends upon the equilibrium between available sediment budget and prevailing nearshore wave and current conditions. Human activities often disturb this natural equilibrium by altering the sources of beach material and littoral drift pattern. In the coastal zone of NW Peloponnese, an essentially tideless environment, the oblique approach of wind-induced waves implies an overall longshore drift from east to west. On an annual basis, the potential longshore sediment transport rates at the different sections of the study area (Kato Achaia) is estimated to vary between 0.02 10-3 m3/s and 5 103 m3/s and to fluctuate seasonally. The construction of a port and the extraction of aggregates from the R. Peiros have changed significantly the pattern of sediment transport inducing dramatic changes on coastline configuration; thus, the part of the coastline west to the port had retreated as much as 70 m eliminating a touristic beach, while the entrance of the port was silted inhibiting navigation. Coastal engineering measures, such as modification of port-breakwaters and construction of groins have had only minimal contribution in beach recovery. Hence, coastal management plans should consider this dynamic equilibrium and protect the natural coastal system from the arbitrary human activities.

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APPLICATION OF A SEMI-EMPIRICAL LONGSHORE TRANSPORT FORMULATION

Coastal Engineering Proceedings ◽

10.9753/icce.v33.posters.22 ◽

2012 ◽

Vol 1 (33) ◽

pp. 22

Author(s):

Giuseppe Barbaro ◽

Giuseppe Roberto Tomasicchio ◽

Giovanni Malara ◽

Felice D'Alessandro

Keyword(s):

Sediment Transport ◽

Transport Rate ◽

Sediment Transport Rate ◽

Longshore Sediment Transport ◽

Longshore Transport ◽

Semi Empirical

The present paper deals with the determination of longshore sediment transport rate. Specifically, case study of Saline Joniche (Reggio Calabria, Italy, is discussed. This case is of interest because, in this location, an artificial basin was built in the 70’s. After few years, port entrance experienced total obstruction by sand. Actually, the area is abandoned and several projects have been proposed for revitalising port activities. This paper discusses a method for estimating the longshore sediment transport rate at Saline Joniche and complements previous methodology.

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Application of a fuzzy inference system for the prediction of longshore sediment transport

Applied Ocean Research ◽

10.1016/j.apor.2014.08.008 ◽

2014 ◽

Vol 48 ◽

pp. 162-175 ◽

Cited By ~ 4

Author(s):

H. Anıl Arı Güner ◽

H. Asena Yumuk

Keyword(s):

Sediment Transport ◽

Fuzzy Inference System ◽

Fuzzy Inference ◽

Inference System ◽

Longshore Sediment Transport

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Prediction of Longshore Sediment Transport Using Soft Computing Techniques

Volume 4: Ocean Engineering; Offshore Renewable Energy ◽

10.1115/omae2008-57582 ◽

2008 ◽

Author(s):

Roham Bakhtyar ◽

David Andrew Barry ◽

Abbas Ghaheri

Keyword(s):

Sediment Transport ◽

Fuzzy Inference System ◽

Fuzzy Inference ◽

Transport Rate ◽

Breaking Wave ◽

Input Output ◽

Empirical Formulas ◽

Inference System ◽

Longshore Sediment Transport ◽

Soft Computing Techniques

An important task for coastal engineers is to predict the sediment transport rates in coastal regions with correct estimation of this transport rate, it is possible to predict both natural morphological or beach morphology changes and the influence of coastal structures on the coast line. A large number of empirical formulas have been proposed for predicting the longshore sediment transport rate as a function of breaking wave characteristics and beach slope. The main shortcoming of these empirical formulas is that these formulas are not able to predict the field transport rate accurately. In this paper, an Adaptive-Network-Based Fuzzy Inference System which can serve as a basis for consulting a set of fuzzy IF-THEN rules with appropriate membership functions to generate the stipulated input-output pairs, is used to predict and model longshore sediment transport. For statistical comparison of predicted and observed sediment transport, bias, Root Mean Square Error, and scatter index are used. The results suggest that the ANFIS method is superior to empirical formulas in the modeling and forecasting of sediment transport. We conclude that the constructed models, through subtractive fuzzy clustering, can efficiently deal with complex input-output patterns. They can learn and build up a neuro-fuzzy inference system for prediction, while the forecasting results provide a useful guidance or reference for predicting longshore sediment transport.

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