Documents disponibles écrits par cet auteur

Combined flow-altering countermeasures against bridge pier scour / Roberto Gaudio in Journal of hydraulic research, Vol. 50 N° 1 (Janvier/Février 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 1 (Janvier/Février 2012) . - pp. 35-43 Titre : Combined flow-altering countermeasures against bridge pier scour Type de document : texte imprimé Auteurs : Roberto Gaudio, Auteur ; Ali Tafarojnoruz, Auteur ; Francesco Calomino, Auteur Année de publication : 2012 Article en page(s) : pp. 35-43 Note générale : Hydraulique Langues : Anglais (eng) Mots-clés : Bridge  pier  Countermeasure  Erosion  Flow  altering  Movable  bed  Scour Résumé : This study presents the results of clear-water tests on the following five combined flow-altering countermeasures against bridge pier scour: (1) submerged vanes and a bed sill, (2) slot and sacrificial piles, (3) a collar and sacrificial piles, (4) a slot and a collar, and (5) a bed sill and a collar. Each countermeasure was designed on the basis of the best configuration recommended in the literature. The results clarify that an improper combination of two countermeasures may be less effective than each individual countermeasure; combinations (1), (2), and (3) do not reduce the scour depth significantly with respect to the single countermeasures; combination (3) increases the scour rate during the first few hours with respect to a single collar; combination (4) may also prevent scour intrusion beneath a collar; and combination (5) in the best configuration reduces the scour depth significantly around the collar with respect to maximum scour depth of the unprotected pier, preventing also the scour hole reaching the pier body. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.649548 [article] Combined flow-altering countermeasures against bridge pier scour [texte imprimé] / Roberto Gaudio, Auteur ; Ali Tafarojnoruz, Auteur ; Francesco Calomino, Auteur . - 2012 . - pp. 35-43. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 1 (Janvier/Février 2012) . - pp. 35-43 Mots-clés : Bridge  pier  Countermeasure  Erosion  Flow  altering  Movable  bed  Scour Résumé : This study presents the results of clear-water tests on the following five combined flow-altering countermeasures against bridge pier scour: (1) submerged vanes and a bed sill, (2) slot and sacrificial piles, (3) a collar and sacrificial piles, (4) a slot and a collar, and (5) a bed sill and a collar. Each countermeasure was designed on the basis of the best configuration recommended in the literature. The results clarify that an improper combination of two countermeasures may be less effective than each individual countermeasure; combinations (1), (2), and (3) do not reduce the scour depth significantly with respect to the single countermeasures; combination (3) increases the scour rate during the first few hours with respect to a single collar; combination (4) may also prevent scour intrusion beneath a collar; and combination (5) in the best configuration reduces the scour depth significantly around the collar with respect to maximum scour depth of the unprotected pier, preventing also the scour hole reaching the pier body. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.649548

Friction factor and von Kármán's k in open channels with bed-load / Roberto Gaudio in Journal of hydraulic research, Vol. 49 N° 2 (Mars/Avril 2011) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 49 N° 2 (Mars/Avril 2011) . - pp. 239-247 Titre : Friction factor and von Kármán's k in open channels with bed-load Type de document : texte imprimé Auteurs : Roberto Gaudio, Auteur ; Antonio Miglio, Auteur ; Francesco Calomino, Auteur Année de publication : 2011 Article en page(s) : pp. 239-247 Note générale : Hydraulique Langues : Anglais (eng) Mots-clés : Bed-load  Friction  factor  Narrow  flume  Open  channel  Von  Kàrmàn's  k Index. décimale : 627 Ingénierie des cours d'eau naturels, des ports, des rades et des cotes. Installations de navigation, de dragage, de récupération et de sauvetage. Barrages et centrales électriques hydrauliques Résumé : The assessment of the friction factor in open-channel flows with sediments is still an unsolved problem. For bed-load, various studies led to contrasting results, some finding that the friction factor is not affected by the sediment transport, whereas others observed an increase with the sediment concentration. Its effect was analysed in few studies only with gravel bed-load, and an empirical formula was proposed to predict the bed friction factor for pipe and open-channel flows, yet with a limited physical meaning and a general deviation of open-channel data. Also the von Kármán's κ has been recognized to vary with sediment transport. In the framework of classical dimensional analysis, laboratory investigations are here extended to sand bed-load and new empirical formulae based on both original and literature data are proposed for the assessment of the bed friction factor and von Kármán's κ, thereby accounting for the main parameters which affect resistance. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.561001 [article] Friction factor and von Kármán's k in open channels with bed-load [texte imprimé] / Roberto Gaudio, Auteur ; Antonio Miglio, Auteur ; Francesco Calomino, Auteur . - 2011 . - pp. 239-247. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 49 N° 2 (Mars/Avril 2011) . - pp. 239-247 Mots-clés : Bed-load  Friction  factor  Narrow  flume  Open  channel  Von  Kàrmàn's  k Index. décimale : 627 Ingénierie des cours d'eau naturels, des ports, des rades et des cotes. Installations de navigation, de dragage, de récupération et de sauvetage. Barrages et centrales électriques hydrauliques Résumé : The assessment of the friction factor in open-channel flows with sediments is still an unsolved problem. For bed-load, various studies led to contrasting results, some finding that the friction factor is not affected by the sediment transport, whereas others observed an increase with the sediment concentration. Its effect was analysed in few studies only with gravel bed-load, and an empirical formula was proposed to predict the bed friction factor for pipe and open-channel flows, yet with a limited physical meaning and a general deviation of open-channel data. Also the von Kármán's κ has been recognized to vary with sediment transport. In the framework of classical dimensional analysis, laboratory investigations are here extended to sand bed-load and new empirical formulae based on both original and literature data are proposed for the assessment of the bed friction factor and von Kármán's κ, thereby accounting for the main parameters which affect resistance. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.561001

Scale effects in physical hydraulic engineering models / Ali Tafarojnoruz in Journal of hydraulic research, Vol. 50 N° 2 (Mars/Avril 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 2 (Mars/Avril 2012) . - pp. 247-248 Titre : Scale effects in physical hydraulic engineering models Type de document : texte imprimé Auteurs : Ali Tafarojnoruz, Auteur ; Roberto Gaudio, Auteur Année de publication : 2012 Article en page(s) : pp. 247-248 Note générale : Hydraulique Langues : Anglais (eng) Note de contenu : By VALENTIN HELLER, Journal of Hydraulic Research, Vol. 49, No. 3 (2011), pp. 293–306 DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2012.668377 [article] Scale effects in physical hydraulic engineering models [texte imprimé] / Ali Tafarojnoruz, Auteur ; Roberto Gaudio, Auteur . - 2012 . - pp. 247-248. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 2 (Mars/Avril 2012) . - pp. 247-248 Note de contenu : By VALENTIN HELLER, Journal of Hydraulic Research, Vol. 49, No. 3 (2011), pp. 293–306 DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2012.668377

Vortex scouring process around bridge pier with a caisson / Ali Tafarojnoruz in Journal of hydraulic research, Vol. 50 N° 4 (Juillet/Août 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 4 (Juillet/Août 2012) . - pp. 443-444 Titre : Vortex scouring process around bridge pier with a caisson Type de document : texte imprimé Auteurs : Ali Tafarojnoruz, Auteur ; Roberto Gaudio, Auteur Année de publication : 2012 Article en page(s) : pp. 443-444 Note générale : Hydraulique Langues : Anglais (eng) ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/full/10.1080/00221686.2012.707795 [article] Vortex scouring process around bridge pier with a caisson [texte imprimé] / Ali Tafarojnoruz, Auteur ; Roberto Gaudio, Auteur . - 2012 . - pp. 443-444. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 4 (Juillet/Août 2012) . - pp. 443-444 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/full/10.1080/00221686.2012.707795