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Model of the evolution of mounds placed in the nearshore

Larson, Magnus LU and Hanson, Hans LU (2015) In Journal of Integrated Coastal Zone Management 15(1). p.21-33
Abstract

A one-dimensional mathematical model is presented that describes the cross-shore evolution of a long linear mound of noncohesive sediment placed in the nearshore and exposed to non-breaking waves. The equation for the transport rate accounts for wave asymmetry and gravity, and the net rate is expressed by reference to an equilibrium profile shape. Simplifications reduce the governing equation for mound evolution to the diffusion equation, for which analytical solutions are available for various initial shapes of the mound. Temporal and spatial dependencies governing mound evolution are obtained from the analytic solutions; for example, a doubling of the wave height implies a certain mound response in 1/8 of the time compared to the... (More)

A one-dimensional mathematical model is presented that describes the cross-shore evolution of a long linear mound of noncohesive sediment placed in the nearshore and exposed to non-breaking waves. The equation for the transport rate accounts for wave asymmetry and gravity, and the net rate is expressed by reference to an equilibrium profile shape. Simplifications reduce the governing equation for mound evolution to the diffusion equation, for which analytical solutions are available for various initial shapes of the mound. Temporal and spatial dependencies governing mound evolution are obtained from the analytic solutions; for example, a doubling of the wave height implies a certain mound response in 1/8 of the time compared to the original conditions. The governing equation is also solved numerically in order to avoid schematization of the forcing, initial, and boundary conditions. Both the analytical and numerical models are compared with data on mound evolution from several sites around the world. Model predictions agree with trends in measurements of four mounds at widely different sites. An example is given concerning the application of the analytical model for preliminary mound design. The formulation presented also applies to infilling of dredged trenches with lengths much greater than their widths.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Beach nourishment, Dredging, Mound design, Profile evolution, Sediment transport
in
Journal of Integrated Coastal Zone Management
volume
15
issue
1
pages
13 pages
external identifiers
  • Scopus:84964597604
DOI
10.5894/rgci530
language
English
LU publication?
yes
id
711debbc-c8bb-44cc-b234-9a0e22167b97
date added to LUP
2016-10-17 10:03:33
date last changed
2016-10-17 10:03:33
@misc{711debbc-c8bb-44cc-b234-9a0e22167b97,
  abstract     = {<p>A one-dimensional mathematical model is presented that describes the cross-shore evolution of a long linear mound of noncohesive sediment placed in the nearshore and exposed to non-breaking waves. The equation for the transport rate accounts for wave asymmetry and gravity, and the net rate is expressed by reference to an equilibrium profile shape. Simplifications reduce the governing equation for mound evolution to the diffusion equation, for which analytical solutions are available for various initial shapes of the mound. Temporal and spatial dependencies governing mound evolution are obtained from the analytic solutions; for example, a doubling of the wave height implies a certain mound response in 1/8 of the time compared to the original conditions. The governing equation is also solved numerically in order to avoid schematization of the forcing, initial, and boundary conditions. Both the analytical and numerical models are compared with data on mound evolution from several sites around the world. Model predictions agree with trends in measurements of four mounds at widely different sites. An example is given concerning the application of the analytical model for preliminary mound design. The formulation presented also applies to infilling of dredged trenches with lengths much greater than their widths.</p>},
  author       = {Larson, Magnus and Hanson, Hans},
  keyword      = {Beach nourishment,Dredging,Mound design,Profile evolution,Sediment transport},
  language     = {eng},
  month        = {03},
  number       = {1},
  pages        = {21--33},
  series       = {Journal of Integrated Coastal Zone Management},
  title        = {Model of the evolution of mounds placed in the nearshore},
  url          = {http://dx.doi.org/10.5894/rgci530},
  volume       = {15},
  year         = {2015},
}