scholarly journals EFFECTS OF A VERTICAL SEAWALL ON PROFILE RESPONSE

1988 ◽  
Vol 1 (21) ◽  
pp. 111 ◽  
Author(s):  
Michael R. Barnett ◽  
Hsiang Wang
Keyword(s):  
Time Series ◽  
Sediment Transport ◽  
Incident Wave ◽  
Break Point ◽  
Two Dimensional ◽  
Limited Extent ◽  
Beach Profile ◽  
Temporal Profile ◽  
Recovery Response ◽  
Transport Patterns

An attempt is made to determine beach profile response due to the presence of a vertical seawall placed in various cross-shore positions, and to examine the differences between natural beaches and seawall-backed beaches in response to normally incident wave attack. The investigation was mainly restricted to two-dimensional profile response under erosive wave conditions, with beach recovery response monitored to a limited extent. Spatial and temporal profile response was investigated by examining time-series profile configuration, volumetric changes, sediment transport patterns, and quasiequilibrium profile configuration. Additionally, dominant profile features such as the break point and reflection bars (as well as scour at the toe of the seawall-backed profiles) were observed and quantified.

scholarly journals BEACH PROFILES AT TORREY PINES, CALIFORNIA

1976 ◽  
Vol 1 (15) ◽  
pp. 75 ◽  
Author(s):  
David G. Aubrey ◽  
Douglas L. Inman ◽  
Charles E. Nordstrom
Keyword(s):  
Sediment Transport ◽  
Incident Wave ◽  
Wave Energy ◽  
Energy Conditions ◽  
Beach Profile ◽  
High Wave ◽  
Wave Characteristics ◽  
Spectral Estimates ◽  
High Wave Energy ◽  
Incident Waves

Beach profiles have been measured at Torrey Pines Beach, California for four years and correlated with tides and accurate spectral estimates of the incident wave field. Characteristic equilibrium beach profiles persist for time spans of up to at least two weeks in response to periods of uniform incident waves. These changes in the beach profiles are primarily due to on-offshore sediment transport which can be related to variations in wave characteristics and tidal phase. The most rapid readjustment of the beach profile occurs during high wave energy conditions coincident with spring tides. Alternatively, the highest berm building is associated with moderate to low waves that coincide with spring tides.

scholarly journals BEACH PROFILES AND ON-OFFSHORE SEDIMENT TRANSPORT

1980 ◽  
Vol 1 (17) ◽  
pp. 67 ◽  
Author(s):  
Akira Watanabe ◽  
Yoshihiko Riho ◽  
Kiyoshi Horikawa
Keyword(s):  
Shear Stress ◽  
Sediment Transport ◽  
Laboratory Test ◽  
Test Data ◽  
Critical Shear Stress ◽  
Two Dimensional ◽  
Bottom Shear Stress ◽  
Beach Profile ◽  
Profile Changes ◽  
Sloping Beach

The on-offshore sediment transport due to waves on a sloping beach is studied by analyzing the laboratory test data on two-dimensional beach deformation. The net rates of sediment transport both inside and outside the breaker zone are evaluated from beach profile changes and are related to the nondimensional bottom shear stress or the Shields parameter. The importance of the critical shear stress and of asymmetrical to-and-fro water partical motion near the bottom is pointed out.

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 SEDIMENT TRANSPORT AND BEACH TRANSFORMATION

1982 ◽  
Vol 1 (18) ◽  
pp. 88 ◽  
Author(s):  
Tomoya Shibayama ◽  
Kiyoshi Horikawa
Keyword(s):  
Sediment Transport ◽  
Wave Motion ◽  
Wave Theory ◽  
Linear Wave ◽  
Two Dimensional ◽  
Beach Profile ◽  
Field Investigations ◽  
Transport Calculation ◽  
Profile Changes ◽  
Profile Change

Laboratory and field investigations were performed in order to formulate a predictive model of two-dimensional beach profile change. The observed transport was classified into six types, and transport formulas were deduced for each type based on a microscale description of sediment movement caused by wave action. A numerical model of two-dimensional beach transformation was then developed. Beach profile changes calculated with the model were then compared with the laboratory results. The model was found to give reasonable results except in the vicinity of the wave plunging point. The sediment transport calculation is based on a sinusoidal velocity profile. The model appeares to give good results as long as the wave motion can be reasonably approximated by linear wave theory.

scholarly journals SEDIMENT TRANSPORT ON NEARLY-PRISMATIC BEACHES

1988 ◽  
Vol 1 (21) ◽  
pp. 128
Author(s):  
Marcel J.F. Stive ◽  
J.A. Roelvink
Keyword(s):  
Sediment Transport ◽  
Recent Progress ◽  
Dynamic Modelling ◽  
Two Dimensional ◽  
Random Waves ◽  
Beach Profile ◽  
Quantitative Modelling ◽  
Obliquely Incident ◽  
Current Systems ◽  
Profile Development

Recent progress in the quantitative modelling of the undertow has stimulated the modelling of cross-shore sediment transport. More so than before it seems now possible to attempt the dynamic modelling of beach profile development. Also, integration of dynamic cross-shore sediment transport formulations in horizontally two-dimensional models for watermotion and sediment transport has recently been suggested. This seems to be a first step of integrating depth-averaged 2DH-modelling with 2DV-profile- modelling. Here an overview is given of these developments and the understanding gained sofar of the several current systems and the induced sediment transport and morphology that are found in the situation of random waves normally and obliquely incident on beaches which vary not or only slowly alongshore.

Satellite Observations of Sediment Transport Patterns in the Lac Saint-Pierre Region of the St. Lawrence River

1988 ◽  
Vol 23 (2) ◽  
pp. 243-252 ◽  
Author(s):  
J.E. Bruton ◽  
J.H. Jerome ◽  
R.P. Bukata
Keyword(s):  
Sediment Transport ◽  
Close Relationships ◽  
Satellite Observations ◽  
Near Surface ◽  
Thermal Data ◽  
Digital Formats ◽  
Transport Patterns ◽  
Mutually Independent ◽  
River Corridor ◽  
St Lawrence River

Abstract Satellite data from Landsats 4 and 5 were utilized to delineate the seasonal variations of sediment transport zones in the Lac Saint-Pierre region of the St. Lawrence River corridor. A seasonally cyclic succession of patterns displaying persistent, mutually independent, and extensive (in both space and time) turbidity zones was clearly in evidence. Visible and thermal data in both imagery and digital formats were used to show the close relationships existing among the distinct zonal synoptic patterns, the bathymetry of lake and river, and the near surface aquatic temperatures.

Dynamic Modeling of Solar Radiation Disturbances Based on a Biomimetic Cloud Shading Model

2018 ◽  
Vol 140 (2) ◽  
Author(s):  
Jesús García ◽  
Iván Portnoy ◽  
Ricardo Vasquez Padilla ◽  
Marco E. Sanjuan
Keyword(s):  
Time Series ◽  
Solar Radiation ◽  
Control Strategies ◽  
Ground Level ◽  
Direct Solar Radiation ◽  
Complex Phenomenon ◽  
Two Dimensional ◽  
Multi Objective Optimization ◽  
Tuning Parameters ◽  
Radiation Time

Variation in direct solar radiation is one of the main disturbances that any solar system must handle to maintain efficiency at acceptable levels. As known, solar radiation profiles change due to earth's movements. Even though this change is not manipulable, its behavior is predictable. However, at ground level, direct solar radiation mainly varies due to the effect of clouds, which is a complex phenomenon not easily predictable. In this paper, dynamic solar radiation time series in a two-dimensional (2D) spatial domain are obtained using a biomimetic cloud-shading model. The model is tuned and compared against available measurement time series. The procedure uses an objective function based on statistical indexes that allow extracting the most important characteristics of an actual set of curves. Then, a multi-objective optimization algorithm finds the tuning parameters of the model that better fit data. The results showed that it is possible to obtain responses similar to real direct solar radiation transients using the biomimetic model, which is useful for other studies such as testing control strategies in solar thermal plants.

Monitoring sediment transport patterns on an energetic ebb-tidal delta using dual-signature tracers

2018 ◽  
Author(s):  
Stuart Pearson ◽  
Bram van Prooijen ◽  
Jack Poleykett ◽  
Matthew Wright ◽  
Kevin Black ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Ebb Tidal Delta ◽  
Transport Patterns
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