Modeling Sediment Transport due to Tsunamis with Exchange Rate between Bed Load Layer and Suspended Load Layer

Regression analysis between sediment transport rates and stream discharge for the Nestos River, Greece

Global NEST Journal ◽

10.30955/gnj.000888 ◽

2013 ◽

Vol 14 (3) ◽

pp. 362-370

Keyword(s):

Sediment Transport ◽

Suspended Load ◽

Bed Load ◽

Regression Curve ◽

Degree Polynomial ◽

Stream Discharge ◽

Nestos River ◽

Polynomial Curve ◽

Load Transport ◽

Bed Load Transport

Systematic measurements of sediment transport rates and water discharge were conducted in the Nestos River (Greece), at a place located between the outlet of Nestos River basin and the river delta. This basin area is about 838 km2 and lies downstream of the Platanovrysi Dam. Separate measurements of bed load transport and suspended load transport were performed at certain cross sections of the Nestos River. In this study, relationships between sediment transport rates and stream discharge for the Nestos River are presented. A nonlinear regression curve (4th degree polynomial curve; r2 equals 0.62) between bed load transport rates and stream discharge, on the basis of 63 measurements, was developed. In addition, a nonlinear regression curve (5th degree polynomial curve; r2 equals 0.95) between suspended load transport rates and stream discharge, on the basis of 65 measurements, was developed. The relatively high r2 values indicate that both bed load transport rates and, especially, suspended load transport rates can be predicted as a function of the stream discharge in the Nestos River. However, the reliability of the regression equations would have been higher if more measured data were available.

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Analisa Angkutan Sedimen Pada Hulu Bendung Aepodu Kabupaten Konawe Selatan

Sultra Civil Engineering Journal ◽

10.54297/sciej.v2i1.161 ◽

2021 ◽

Vol 2 (1) ◽

pp. 1-7

Author(s):

Ramadhan Hidayat Putra ◽

Amad Syarif Syukri ◽

Catrin Sudarjat ◽

Vickky Anggara Ilham

Keyword(s):

Sediment Transport ◽

River Flow ◽

Suspended Load ◽

Bedload Transport ◽

Bed Load ◽

Average Flow ◽

Load Transport ◽

Bed Load Transport ◽

Transport Analysis

Research on Aepodu Weir Sediment Transport Analysis in South Konawe District, based on observations in the field, Aepodu Weir hasa sediment buildup that has now exceeded the height of the weirlight house. The purpose of the study was to analyze the magnitudeof Aepodu river flow and to analyze the amount of sedimenttransport that occurred in the Aepodu dam. The method used todetermine the amount of bed load transport uses stchoklitscht, whilefor transporting suspended load using forcheimer.The results of the analysis of the average flow of the Aepodu riverwere 3,604 m3/ second. Sediment transport that occurs in Aepoduweir is Bedload transport (Qb) of 291625.771 tons / year, andsuspended load transport (Qs) of 16972,423 tons / year, so that thetotal sediment transport (QT) is 308598,194 tons / year.

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CALCULATION OF THE RATE OF NET ON-OFFSHORE SEDIMENT TRANSPORT ON THE BASIS OF FLUX CONCEPT

Coastal Engineering Proceedings ◽

10.9753/icce.v19.91 ◽

1984 ◽

Vol 1 (19) ◽

pp. 91 ◽

Cited By ~ 2

Author(s):

Ichiro Deguchi ◽

Toru Sawaragi

Keyword(s):

Sediment Transport ◽

Water Depth ◽

Sediment Concentration ◽

Suspended Load ◽

Spatial Variations ◽

Sediment Flux ◽

Bed Load ◽

Two Dimensional ◽

Dimensional Model ◽

Two Dimensional Model

Time and spatial variations of sediment concentration of both bed load and suspended load in the process of two-dimensional beach deformation were investigated experimentally. At the same time, the relation between the velocities of water-particle and sediment migration was analyzed theoretically. By using those results,a net rate of on-offshore sediment_ transport in the process of two-dimensional model beach deformation qf was calculated on the basis of sediment flux. It is found that Qf coincides fairly well with .the net rate of on-offshore sediment transport calculated from the change of water depth.

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A Sediment Transport Model for Straight Alluvial Channels

Hydrology Research ◽

10.2166/nh.1976.0019 ◽

1976 ◽

Vol 7 (5) ◽

pp. 293-306 ◽

Cited By ~ 406

Author(s):

Frank Engelund ◽

Jørgen Fredsøe

Keyword(s):

Sediment Transport ◽

Transport Model ◽

Suspended Load ◽

Empirical Models ◽

Bed Load ◽

Alluvial Channels ◽

Physical Processes ◽

Sediment Transport Model ◽

Load Transport ◽

Bed Load Transport

The paper presents a simple mathematical model for sediment transport in straight alluvial channels. The model, which is based on physical ideas related to those introduced by Bagnold (1954), was originally developed in two steps, the first describing the bed load transport (Engelund 1975) and the second accounting for the suspended load (Fredsøe and Engelund 1976). The model is assumed to have two advantages as compared with empirical models, first it is based on a description of physical processes, secondly it gives some information about the quantity and size of the sand particles in suspension and the bed particles.

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OBSERVATIONS OF HORIZONTAL AND VERTICAL SEDIMENT FLUXES ON A SANDBAR IN THE SUSPENDED AND SHEET FLOW LAYERS

Coastal Engineering Proceedings ◽

10.9753/icce.v36.sediment.30 ◽

2018 ◽

pp. 30

Author(s):

Ryan S. Mieras ◽

Jack A. Puleo ◽

Dylan Anderson ◽

Daniel T. Cox ◽

Tian-Jian Hsu ◽

...

Keyword(s):

Sediment Transport ◽

Surf Zone ◽

Breaking Waves ◽

Suspended Load ◽

Bed Load ◽

Sheet Flow ◽

Coastal Morphology ◽

Sediment Fluxes ◽

Wave Forcing ◽

Transport Component

The majority of prior sandbar migration studies have been conducted from the morphological standpoint, whereby, (i) bathymetric profiles are recorded over periods of time ranging from days to decades, at frequencies ranging from hourly to yearly (Ruessink et al., 2003), and (ii) hydrodynamic observations typically consist of far-field wave and environmental conditions. Subsequent modeling efforts have generally focused on tuning parameters in the sediment transport formulations (suspended load and bed load) to maximize model skill in predicting observed beach profiles over time (FernÃ¡ndez-Mora et al., 2015; Hoefel and Elgar, 2003). However, little emphasis at the operational level has been placed on tuning coastal morphology models to the true relative contributions of the physical processes (e.g. suspended load, bed load and/or sheet flow) that drive the changing bathymetry. This is due, in part, to the lack of detailed sediment transport observations (field and lab) under realistic wave forcing conditions and spatially variable bathymetry. Such a modeling approach leads to the improper quantification (magnitude and/or direction) of each modeled sediment transport component under skewed-asymmetric and/or breaking waves, often observed in the surf zone. The present study aims to better understand the physical mechanisms responsible for driving cross-shore sediment transport over a sandbar by quantifying (a) the vertical exchange of sediment at the near-bed interface (i.e. pick-up layer), and (b) intra-wave horizontal sediment fluxes in the suspended load and sheet layers.

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87:6278 Suspended-load versus bed-load in sediment transport in Puri and Madras beaches, east coast of India

Deep Sea Research Part B Oceanographic Literature Review ◽

10.1016/0198-0254(87)90741-2 ◽

1987 ◽

Vol 34 (11) ◽

pp. 955

Keyword(s):

Sediment Transport ◽

East Coast ◽

Suspended Load ◽

Bed Load ◽

East Coast Of India

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ON-OFFSHORE SEDIMENT TRANSPORT RATE IN THE SURF ZONE

Coastal Engineering Proceedings ◽

10.9753/icce.v17.72 ◽

1980 ◽

Vol 1 (17) ◽

pp. 72 ◽

Cited By ~ 3

Author(s):

Toru Sawaragi ◽

Ichiro Deguchi

Keyword(s):

Sediment Transport ◽

Surf Zone ◽

Suspended Load ◽

Transport Rate ◽

Bed Load ◽

Relative Importance ◽

Two Dimensional ◽

Sediment Transport Rate

In this paper, models of the distribution of net on-offshore sediment transport based on two-dimensional equilibrium beach profiles and an equation of continuity of sediment transport are proposed. Various parameters of net on-offshore sediment transport in those models are discussed. Furhter, the relative importance of bed load and suspended load in the two-dimensional beach deformation are examined by measuring both of them on model beach experiments.

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A Three-Dimensional Coupled Fluid-Sediment Interaction Model With Bed-Load/Suspended-Load Transport for Scour Analysis Around a Fixed Structure

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.3124132 ◽

2009 ◽

Vol 131 (3) ◽

Cited By ~ 6

Author(s):

Tomoaki Nakamura ◽

Norimi Mizutani ◽

Solomon C. Yim

Keyword(s):

Sediment Transport ◽

Effective Stress ◽

Three Dimensional ◽

Suspended Load ◽

Bed Load ◽

Stress Model ◽

Predictive Capability ◽

Coupled Models ◽

Large Wave ◽

Run Up

The predictive capability of a three-dimensional (3D) numerical model for sediment transport and resulting scour around a structure is investigated in this study. Starting with the bed-load and suspended-load sediment transport (reference) model developed by Takahashi et al. (2000, “Modeling Sediment Transport Due to Tsunamis With Exchange Rate Between Bed Load Layer and Suspended Load Layer,” Proceedings of the 27th International Conference on Coastal Engineering, ASCE, Sydney, Australia, pp. 1508–1519), we first introduce an extension to incorporate Nielsen’s modified Shields parameter to account for the effects of infiltration/exfiltration flow velocity across the fluid-sand interface on the sediment transport (the modified Shields-parameter model). We then propose a new model to include the influence of the effective stress to account for the stress fluctuations inside the surface layer of the sand bed (the effective-stress model). The three analytical models are incorporated into a 3D numerical solver developed by Nakamura et al. (2008, “Tsunami Scour Around a Square Structure,” Coast. Eng. Japan, 50(2), pp. 209–246) to analyze the dynamics of fluid-sediment interaction and scour. Their solver is composed of two modules, namely, a finite-difference numerical wave tank and a finite-element coupled sand-skeleton pore-water module. The predictive capability of the three alternative coupled models is calibrated against hydraulic experiments on sediment transport and resulting scour around a fixed rigid structure due to the run-up of a single large wave in terms of the sediment transport process and the final scour profile after the wave run-up. It is found that, among the three models considered, the proposed effective-stress model most accurately predicts the scouring process around the seaward corner of the structure. The results also reveal that the deposition and erosion patterns predicted using the effective-stress model are in good agreement with measured results, while a scour hole at the seaward corner of the structure cannot be always predicted by the other two models.

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Modelled nearshore sediment transport in open-water conditions, central north shore of Prince Edward Island, Canada

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2015-0090 ◽

2016 ◽

Vol 53 (1) ◽

pp. 101-118 ◽

Cited By ~ 2

Author(s):

Gavin K. Manson ◽

Robin G.D. Davidson-Arnott ◽

Donald L. Forbes

Keyword(s):

Sediment Transport ◽

Prince Edward Island ◽

Open Water ◽

Suspended Load ◽

Bedload Transport ◽

Water Levels ◽

Bed Load ◽

Wave Direction ◽

North Shore ◽

Nearshore Sediment Transport

The central north shore of Prince Edward Island comprises embayments separated by subtle headlands that may constrain nearshore sediment transport. The study area includes two such embayments informally known as Brackley and Tracadie bights, both of which are sand-rich onshore and sand-starved between 20 and 50 m water depth. Storm winds and waves from the northwest and northeast are common in autumn and winter. The hydrodynamic model Delft3D is used to simulate waves, currents, water levels, and sediment transport in Brackley and Tracadie bights during 23 autumn seasons between 1955 and 2005. When compared with wave and current measurements from a field experiment in the autumn of 1999, the model successfully simulates conditions during storms and fair-weather periods. Results from the simulations show that, in autumn, the weighted mean direction of transport is to the southeast (133°). Bedload transport is directed onshore to the south (170°), and suspended load is directed offshore to the northeast (67°). When aggregated over the 23 seasons, transport magnitudes and directions differ between Brackley and Tracadie bights. Rates of transport are higher in Tracadie Bight and directed more to the east. During individual storms, transport is dependent on the storm wind and wave direction. Most transport occurs in bed load, and deposition occurs at the shoreline, with erosion offshore. The patterns of bed load and suspended load suggest a mechanism for the landward migration of this shoreline during transgression, and may explain the existence of the sand-starved zone offshore.

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