scholarly journals SHOREWARD SAND TRANSPORT OUTSIDE THE SURFZONE, NORTHERN GOLD COAST, AUSTRALIA

2012 ◽  
Vol 1 (33) ◽  
pp. 26 ◽  
Author(s):  
Dean Patterson
Keyword(s):  
Surf Zone ◽  
River Mouth ◽  
Transport Processes ◽  
Gold Coast ◽  
Sand Transport ◽  
Large Wave ◽  
Wave Flume ◽  
Shoreline Evolution ◽  
The One

To date, no suitable theoretical basis has been derived to predict with reliable accuracy the shoreward sand transport under waves in the deeper water outside the surf zone. This is important for understanding the rate of recovery of beaches after major storm erosion and, in some circumstances, to quantify net shoreward supply of sand to the shoreline from the active lower shore-face below the depth of storm erosion bar development. Even a relatively low rate of long term shoreward net supply may contribute to shoreline stability where it offsets a gradient in the longshore sand transport that would otherwise lead to recession. This paper outlines the results of analysis of a 41 year dataset of beach and nearshore profile surveys to quantify annual average rates of shoreward net sand transport in 6-20m water in an area where the profiles are not in equilibrium due to the existence of a residual river mouth ebb delta bar lobe. Additionally, an empirical adaptation of the sheet flow relationship of Ribberink and Al-Salem (1990) to provide for the effects of ripples has been derived from large wave flume data and correlates well with the measured Gold Coast transport rates. These have been applied to a new coastline modelling system developed as part of research into the long term evolution of Australia’s central east coast region in response to sea level change and longshore sand transport processes, which combines the one-line concept of shoreline profile translation within the zone of littoral sand transport with cross-shore profile evolution across the deeper shore-face profile below that zone. It demonstrates the importance of providing for both the shoreward supply from the continental shelf and the varying profile response time-scale across the shore-face in predicting shoreline evolution.

scholarly journals CROSS-SHORE SEDIMENT TRANSPORT IN THE SWASH ZONE: LARGE-SCALE LABORATORY EXPERIMENTS

2020 ◽  
pp. 18
Author(s):  
Sara Dionisio Antonio ◽  
Jebbe van der Werf ◽  
Bart Vermeulen ◽  
Ivan Caceres ◽  
Jose M. Alsina ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Large Scale ◽  
Surf Zone ◽  
Transport Processes ◽  
Sand Transport ◽  
Swash Zone ◽  
Flume Experiments ◽  
Wave Flume ◽  
Shoreline Evolution

The swash zone is a highly dynamic boundary between the beach and the surf zone. Swash processes determine whether sediment is either stored on the upper beach or is transported offshore, and thus strongly affect shoreline evolution. The present research focuses on the hydrodynamics, sand transport processes and net sediment transport in the swash zone through a series of large-scale wave flume experiments. This research aims to improve the understanding of swash zone sand transport processes, in particular the role of cross-shore sand advection and wave-swash interactions, and bring new detailed insights into the relation between intra-swash processes and net sand transport rates.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/tYvJ0pML-kU

scholarly journals IMPROVED LONGSHORE SAND TRANSPORT EVALUATION

1988 ◽  
Vol 1 (21) ◽  
pp. 103
Author(s):  
A.S. Arcilla ◽  
A. Vidaor ◽  
J. Pous
Keyword(s):  
Sediment Transport ◽  
Dimensional Analysis ◽  
Surf Zone ◽  
Dynamic State ◽  
Sand Transport ◽  
Hydrodynamic Analysis ◽  
Shoreline Evolution ◽  
Longshore Sediment Transport ◽  
Proposed Model ◽  
The One

In this paper an improved bulk formulation for the longshore sediment transport rate is presented. It is based on a simplified hydrodynamic analysis of surf zone flow and supplemented by an exhaustive dimensional analysis. The proposed model includes the effect of the surf zone dynamic state (e.g. variation of longshore sand transport, II, with breaker type) and it is now being used in the one- and twoline shoreline evolution models developed by the Maritime Engineering Laboratory in Barcelona.

scholarly journals SUSPENDED AND BEDLOAD TRANSPORT IN THE SURF ZONE: IMPLICATIONS FOR SAND TRANSPORT MODELS

2017 ◽  
pp. 30 ◽  
Author(s):  
Joep van der Zanden ◽  
Dominic A. Van der A ◽  
Tom O'Donoghue ◽  
David Hurther ◽  
Ivan Caceres ◽  
...  
Keyword(s):  
Large Scale ◽  
Surf Zone ◽  
Sediment Concentration ◽  
Breaking Waves ◽  
Bedload Transport ◽  
Transport Processes ◽  
Sand Transport ◽  
Wave Flume ◽  
Load Transport ◽  
Particle Velocities

This paper presents results obtained during a large-scale wave flume experiment focused at measuring hydrodynamics and sediment transport processes in the wave breaking region. The experiment involved monochromatic plunging breaking waves over a mobile bed barred profile consisting of D50 = 0.24 mm sand. Vertical profiles of velocity, turbulence, sand concentration and sand fluxes were measured at 12 cross-shore locations, covering the shoaling region up to the inner surf zone. Particularly high-resolution profiles were obtained near the bed within the wave bottom boundary layer, using an acoustic sediment concentration and velocity profiler (ACVP). Sheet flow concentration and particle velocities were measured at two locations near the bar crest using two conductivity-based concentration measurement tanks (CCM+). Total transport rates, obtained from the evolving bed profile measurements, were decomposed into suspended and bedload transport contributions across the bar. The present paper presents a summary of the key findings of the experiment, which are used to discuss existing approaches for modeling suspended and bed load transport in the surf zone.

scholarly journals LONG TERM MORPHOLOGICAL MODELLING

2011 ◽  
Vol 1 (32) ◽  
pp. 64
Author(s):  
Sten Esbjørn Kristensen ◽  
Rolf Deigaard ◽  
Martin Anders Taaning ◽  
Jørgen Fredsøe ◽  
Nils Drønen ◽  
...  
Keyword(s):  
Time Scale ◽  
Surf Zone ◽  
Coastal Structures ◽  
Model Concept ◽  
General Applicability ◽  
Shoreline Evolution ◽  
Realistic Representation ◽  
Morphological Modelling ◽  
Constant Shape

A morphological modelling concept for long term nearshore morphology is proposed and examples of its application are presented and discussed. The model concept combines parameterised representations of the cross-shore morphology, with a 2DH area model for waves, currents and sediment transport in the surf zone. Two parameterization schemes are tested for two different morphological phenomena: 1) Shoreline changes due to the presence of coastal structures and 2) alongshore migration of a nearshore nourishment and a bar by-passing a harbour. In the case of the shoreline evolution calculations, a concept often used in one-line modelling of cross-shore shifting of an otherwise constant shape cross-shore profile is applied for the case of a groyne and a detached breakwater. In the case of alongshore bar/nourishment migration an alternative parameterization is adopted. All examples are presented, analysed and discussed with respect to the question of realistic representation, time scale and general applicability of the model concept.

scholarly journals EXPERIMENTS ON BEACH PROFILE CHANGE WITH A LARGE WAVE FLUME

1982 ◽  
Vol 1 (18) ◽  
pp. 85 ◽  
Author(s):  
Ryoichi Kajima ◽  
Takao Shimizu ◽  
Kohki Maruyama ◽  
Shozo Saito
Keyword(s):  
Simple Model ◽  
Transport Rate ◽  
Sand Transport ◽  
Two Dimensional ◽  
Beach Profile ◽  
Large Wave ◽  
Wave Flume ◽  
Grain Sizes ◽  
Profile Changes ◽  
Profile Change

Two-dimensional beach profile changes were investigated with a newly constructed prototype-scale wave flume. The flume is 205 m long, 3.4 m wide and 6 m deep. Sand of two grain sizes was used in the experiments. Analysis of the results was made through use of the parameter C, introduced by Sunamura and Horikawa (1974) to classify beaches as either erosional and accretionary. Beach profile changes obtained in the flume were similar to those in the prototype (field). Net sand transport rate distributions were classified into five types, two of which do not seem to have been observed in laboratory (smallscale) experiments. A simple model describing the five types was developed for evaluating two-dimensional beach profile changes.

scholarly journals NUMERICAL MODELING OF SHORELINE EVOLUTION AROUND THE RIVER MOUTH

1984 ◽  
Vol 1 (19) ◽  
pp. 202
Author(s):  
Ming-Chung Lin ◽  
Jyh-Cherng Wang
Keyword(s):  
Numerical Models ◽  
River Sediments ◽  
River Mouth ◽  
Typical Feature ◽  
Wave Condition ◽  
Shoreline Evolution ◽  
Longshore Sediment Transport ◽  
Proposed Model ◽  
Wave Induced

The river sediments transport into coastal water together with wave induced longshore sediment transport make shoreline evolution much complicated. Fig.l shows typical feature of shoreline shape around a river mouth. Recently there are some investigators treated this problem (Grijm, 1964, Bakker §Edelmen,1964; Komar,1973; Tsuchiya § Yasuda,1978),and had developed some mathematical or numerical models. This paper proposes a numerical model for predicting long-term shoreline evolution around a river mouth by incorporation certain river parameters into the Willis beach evolution model (1978). The proposed model is at first applied to four ideal cases to investigate its general characteristics and adaptability, and reasonable results are found. In our results the accretion on updrift side is faster than downdrift side under the oblique incident wave condition and the width of the river mouth increase steadily. These results are different from other approachs that the shoreline shape is always nearly symmetrical with respect to the centerline of the river mouth. Finally, as an field case application of the model, a numerical simulation of shoneline changes around the Cho-shui River mouth is performed and compared with field data.

scholarly journals MEASUREMENTS OF THE STEADY CURRENTS OUTSIDE THE SURF ZONE

2011 ◽  
Vol 1 (32) ◽  
pp. 49 ◽  
Author(s):  
Pietro Scandura ◽  
Erminia Capodicasa ◽  
Enrico Foti
Keyword(s):  
Surf Zone ◽  
Scale Effects ◽  
Velocity Profiles ◽  
Sea Waves ◽  
Mean Velocity ◽  
Large Wave ◽  
Wave Flume ◽  
Wave Trough ◽  
Steady Current ◽  
The Mean

The results of an experimental study concerning with the measurements of the steady current induced by sea waves approaching the coast are reported. The experiments have been performed in a large wave flume in order to minimize the scale effects. The measurements have been carried out at four different stations along the wave flume by using Acoustic Doppler Velocimeters. The results show that the mean velocity profiles are significantly influenced by the wave period. In particular, when the period reduces the mean velocity gradient close to the wave trough increases. The trend of the velocity profiles is different from that predicted by the theory and mostly reported by other experiments. However, experimental results are reported in literature which are in a qualitative agreement with the present ones.

scholarly journals BEACH PROFILE CHANGE: MORPHOLOGY, TRANSPORT RATE, AND NUMERICAL SIMULATION

1988 ◽  
Vol 1 (21) ◽  
pp. 96 ◽  
Author(s):  
Magnus Larson ◽  
Nicholas C. Kraus ◽  
Tsuguo Sunamura
Keyword(s):  
Reasonable Agreement ◽  
Surf Zone ◽  
Model Development ◽  
Sand Transport ◽  
Data Sets ◽  
Beach Profile ◽  
Shape Model ◽  
Large Wave ◽  
Model Predictions ◽  
Profile Change

An empirically based engineering numerical model is presented for simulating beach profile change in the surf zone produced by waveinduced cross-shore sand transport. The model simulates the dynamics of macroscale profile change, such as the growth and movement of berms and breakpoint bars. Model development was founded on two data sets from large wave tank experiments consisting of 42 cases with different incident wave conditions, median grain size, and initial beach shape. Model predictions are tested with field data, and reasonable agreement is found.

Study of Extreme Waves Propagating Over Reefs in Large Wave Flume

2019 ◽  
Author(s):  
Songgui Chen ◽  
Zeming Wang ◽  
Jinhai Zheng ◽  
Chi Zhang ◽  
Ke Hu
Keyword(s):  
Wave Breaking ◽  
Surf Zone ◽  
Structure Design ◽  
Water Levels ◽  
Extreme Waves ◽  
Extreme Wave ◽  
Large Wave ◽  
Wave Flume ◽  
Breaking Points ◽  
Wave Induced

Abstract Waves propagating over reefs have been studied by many researchers. However due to limitation of small wave flume, most experiments focused on the normal waves. Extreme waves are the input parameters for structure design on reefs. Thus, experiments of extreme waves propagating over reefs were conducted in the large wave flume of the Tianjin Research Institute of Water Transport Engineering. Extreme wave hydrodynamic within surf zone will be focused on. Tests with different wave heights Hi, wave periods T and water levels on reefs h have been carried out. The model scale is set to be 1:15, then Hi from 4.5m to 12m, T from 9s to 17s, hr from 0 to 3m are generated in the test. Wave breaking points are observed by high speed camera. Wave breaking points move offshore as Hi and T increase and h decrease. Wave setups and wave-induced flows along the reef are measured at different locations. It can be found that wave setups increase with increasing Hi and T and decreasing water level h. Wave-induced flows increase with increasing Hi and h and decreasing T. As waves propagate towards landside, wave setups and wave-induced flows have a local extremum at the middle of surf zone. Compared with our test, Gourlay’s formulas overestimate wave setup while underestimate wave induced flow within extreme wave surf zone.

OPERATIONAL CONDITIONS OF FUNCTIONAL DURABILITY AND PERFORMANCE OF ROAD TRANSPORT ENTERPRISES

2018 ◽  
Vol 73 ◽  
pp. 39-48
Author(s):  
Joanna Krupska ◽  
Adam Mytlewski
Keyword(s):  
Operating Systems ◽  
Road Transport ◽  
Transport Processes ◽  
The Other ◽  
Operational Conditions ◽  
Term Operation ◽  
And Performance ◽  
The One

Durability and efficiency are important conditions for long-term operation ofroad transport companies. In the operating aspect, the first parameter determines the quality of the manufacturing capacity and the ability to provide repetitive transport processes. The second parameter affects the long-term ability to use resources and the subsequent results of operations. The conducted study on stability and efficiency of the operating systems of road companies indicates the existence of, on the one hand, a large variation of approaches, and on the other, a clear dominance of intense and efficient behaviour in combination with ensuring the repetitiveness of processes.

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