Large-scale experiments on beach profile evolution and surf and swash zone sediment transport induced by long waves, wave groups and random waves

2011 ◽  
Vol 58 (2) ◽  
pp. 214-227 ◽  
Author(s):  
T.E. Baldock ◽  
J.A. Alsina ◽  
I. Caceres ◽  
D. Vicinanza ◽  
P. Contestabile ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Large Scale ◽  
Long Waves ◽  
Swash Zone ◽  
Random Waves ◽  
Beach Profile ◽  
Wave Groups

scholarly journals Beach Profile Evolution towards Equilibrium from Varying Initial Morphologies

2019 ◽  
Vol 7 (11) ◽  
pp. 406 ◽  
Author(s):  
Sonja Eichentopf ◽  
Joep van der Zanden ◽  
Iván Cáceres ◽  
José M. Alsina
Keyword(s):  
Sediment Transport ◽  
Large Scale ◽  
Intermediate Energy ◽  
Swash Zone ◽  
Energy Profile ◽  
Beach Profile ◽  
Wave Condition ◽  
Wave Energy Dissipation ◽  
Transport Patterns ◽  
In The Beginning

The evolution of different initial beach profiles towards the same final beach configuration is investigated based on large-scale experimental data. The same wave condition was performed three times, each time starting from a different initial profile morphology. The three different initial profiles are an intermediate energy profile with an offshore bar and a small swash berm, a plane profile and a low energy profile with a large berm. The three cases evolve towards the same final (equilibrium) profile determined by the same wave condition. This implies that the same wave condition generates different sediment transport patterns. Largest beach changes and differences in hydrodynamics occur in the beginning of the experimental cases, highlighting the coupling between morphology and hydrodynamics for beach evolution towards the same profile. The coupling between morphology and hydrodynamics that leads to the same final beach profile is associated with differences in sediment transport in the surf and swash zone, and is explained by the presence of bar and berm features. A large breaker bar and concave profile promote wave energy dissipation and reduce the magnitudes of the mean near-bed flow velocity close to the shoreline limiting shoreline erosion. In contrast, a beach profile with reflective features, such as a large berm and a small or no bar, increases negative velocity magnitudes at the berm toe promoting shoreline retreat. The findings are summarised in a conceptual model that describes how the beach changes towards equilibrium from two different initial morphologies.

scholarly journals AN INTRODUCTION TO EVENT-BASED MODEL FOR THE STUDY OF SEDIMENT TRANSPORT IN THE SWASH ZONE

2011 ◽  
Vol 1 (32) ◽  
pp. 30
Author(s):  
Ahmad Shanehsazzadeh ◽  
Patrick Holmes
Keyword(s):  
Sediment Transport ◽  
Laboratory Data ◽  
Direct Result ◽  
Small Scale ◽  
Bed Load ◽  
Swash Zone ◽  
Beach Profile ◽  
Sediment Particles ◽  
Mode Of Transport ◽  
Event Based

Erosion and accretion of the beach face and consequently the movement of the coastline are the direct result of net sediment transport in the swash zone. Different models have been introduced in order to predict hydrodynamic parameters and, thereafter, movement of particles. However, the capability and comprehensiveness of the models in different conditions are still questionable. In reviewing models established for sediment transport in the swash zone, one can easily conclude that in the most cases the transport of bed load has been predicted traditionally by the application of quasi-steady formula. Scientists have identified many of the important physical processes driving sediment transport throughout the swash zone, but a detailed description of the small-scale sediment dynamics is still far from complete. In this paper the behaviour of coarse sediment particles in the bed load mode of transport in response to the flow regime experienced in the swash zone are investigated. Accordingly, a model called event-based model is introduced for prediction of the beach profile change, and the results of the model are compared with some laboratory data. The comparison between the results of the model and measured beach profile in the laboratory reveals that the results of the model developed in the present study on the basis of the event-based concept are very promising, particularly in the range of flow for which the behaviour of sediment particles is more accurately understood.

scholarly journals Sediment transport dynamics in the swash zone under large-scale laboratory conditions

2016 ◽  
Vol 120 ◽  
pp. 1-13 ◽  
Author(s):  
Andrea Ruju ◽  
Daniel Conley ◽  
Gerd Masselink ◽  
Jack Puleo
Keyword(s):  
Sediment Transport ◽  
Large Scale ◽  
Swash Zone ◽  
Transport Dynamics ◽  
Laboratory Conditions

scholarly journals SEDIMENT TRANSPORT & ACCRETION ABOUND THE COASTLINES OF JAPAN

1966 ◽  
Vol 1 (10) ◽  
pp. 28
Author(s):  
Richard Silvester
Keyword(s):  
Sediment Transport ◽  
Coastal Plain ◽  
Large Scale ◽  
Wave Climate ◽  
Economic Importance ◽  
Coastal Plains ◽  
Beach Profile ◽  
Littoral Drift ◽  
Geologic Time ◽  
Catchment Characteristics

The process of sedimentation can be traced from its initiation as weathering of base rock, transport to the ocean by rivers, and its distribution by waves. The sediment supplied by a river is dependent upon catchment characteristics - topography, precipitation, vegetation and geology. The grading of this sediment can change over geologic time. The transport of material by waves is an important aspect of this overall movement, to a destination of either coastal plain or offshore shoal. The persistent occurrence and direction of ocean swell make this wave domain the most important in this process. In enclosed seas littoral drift is effected by storm type waves, per medium of a different beach profile from that on oceanic margins. Accepting that the wave climate has not changed significantly over geologic time, it is possible to picture the geomorphology of river and coastal plains to the present continental outline. The coastlines of Japan are examined in this paper with such an emphasis. Lowland so formed is of extreme economic importance. In order to promote accretion of further areas on a large scale, the character of the sediment and of the natural forces available at any location must be considered. Suitable structures and their siting within natural shoreline features are discussed.

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