Improvement of sand activation depth prediction under conditions of oblique wave breaking. Bertin, X.; Castelle, B.; Anfuso, G.; and Ferreira, Ó. 28(2):65–75. Number: 2
Improvement of sand activation depth prediction under conditions of oblique wave breaking [link]Paper  doi  abstract   bibtex   
This study presents sand activation depth (SAD) measurements recently obtained on two contrasting beaches located along the Atlantic coast of France: the gently sloping, high-energy St Trojan beach where wave incidence is usually weak, and the steep, low-energy Arçay Sandspit beach where waves break at highly oblique angles. Comparisons between field measurements and predictions from existing formulae show good agreement for St Trojan beach but underestimate the SAD on the Arçay Sandspit beach by 40–60%. Such differences suggest a strong influence of wave obliquity on SAD. To verify this hypothesis, the relative influence of wave parameters was investigated by means of numerical modelling. A quasi-linear increase of SAD with wave height was confirmed for shore-normal and slightly oblique wave conditions, and a quasi-linear increase in SAD with wave obliquity was also revealed. Combining the numerical results with previously published relations, both a new semi-empirical and an empirical formula for the prediction of SAD were developed which showed good SAD predictions under conditions of oblique wave breaking. The new empirical formula for the prediction of SAD (Z 0) takes into account the significant wave height (H s), the beach face slope (β) and the wave angle at breaking (α), and is of the form Z0=1.6tan(β)H0.5s1+sin(2α)−−−−−−−−−√Z0=1.6tan⁡(β)Hs0.51+sin⁡(2α) Z_\0\ = 1.6\textbackslashtan \\textbackslashleft( \textbackslashbeta \textbackslashright)\H\textasciicircum\\0.5\\_\\\textbackslashtext\s\\\ \\textbackslashsqrt \1 + \textbackslashsin \\textbackslashleft( \2\textbackslashalpha \ \textbackslashright)\\ \ . The use of a dataset from the literature demonstrates the predictive skill of these new formulae for a wide range of wave heights, wave incidence and beach gradients.
@article{bertin_improvement_2008,
	title = {Improvement of sand activation depth prediction under conditions of oblique wave breaking},
	volume = {28},
	issn = {1432-1157},
	url = {https://doi.org/10.1007/s00367-007-0090-2},
	doi = {10.1007/s00367-007-0090-2},
	abstract = {This study presents sand activation depth ({SAD}) measurements recently obtained on two contrasting beaches located along the Atlantic coast of France: the gently sloping, high-energy St Trojan beach where wave incidence is usually weak, and the steep, low-energy Arçay Sandspit beach where waves break at highly oblique angles. Comparisons between field measurements and predictions from existing formulae show good agreement for St Trojan beach but underestimate the {SAD} on the Arçay Sandspit beach by 40–60\%. Such differences suggest a strong influence of wave obliquity on {SAD}. To verify this hypothesis, the relative influence of wave parameters was investigated by means of numerical modelling. A quasi-linear increase of {SAD} with wave height was confirmed for shore-normal and slightly oblique wave conditions, and a quasi-linear increase in {SAD} with wave obliquity was also revealed. Combining the numerical results with previously published relations, both a new semi-empirical and an empirical formula for the prediction of {SAD} were developed which showed good {SAD} predictions under conditions of oblique wave breaking. The new empirical formula for the prediction of {SAD} (Z 0) takes into account the significant wave height (H s), the beach face slope (β) and the wave angle at breaking (α), and is of the form Z0=1.6tan(β)H0.5s1+sin(2α)−−−−−−−−−√Z0=1.6tan⁡(β)Hs0.51+sin⁡(2α) Z\_\{0\} = 1.6{\textbackslash}tan \{{\textbackslash}left( {\textbackslash}beta {\textbackslash}right)\}H{\textasciicircum}\{\{0.5\}\}\_\{\{{\textbackslash}text\{s\}\}\} \{{\textbackslash}sqrt \{1 + {\textbackslash}sin \{{\textbackslash}left( \{2{\textbackslash}alpha \} {\textbackslash}right)\}\} \} . The use of a dataset from the literature demonstrates the predictive skill of these new formulae for a wide range of wave heights, wave incidence and beach gradients.},
	pages = {65--75},
	number = {2},
	journaltitle = {Geo-Marine Letters},
	shortjournal = {Geo-Mar Lett},
	author = {Bertin, Xavier and Castelle, Bruno and Anfuso, Giorgio and Ferreira, Óscar},
	urldate = {2019-04-16},
	date = {2008-04-01},
	langid = {english},
	note = {Number: 2},
	keywords = {Beach, Significant Wave Height, Wave Height, Wave Incidence, Wave Parameter}
}
Downloads: 0