. Les-e¤ets-d-'un-obstacle-sur-un-Écoulement-sont-complexes-À-Étudier, En succédant au chapitre 3, ce chapitre vise à étudier l'écoulement et l'arrêt de l'écoulement d'un ?uide à seuil homogène en canal horizontal passant à travers un ferraillage élémentaire vertical, puis à quanti?er correctement les modi?cations de l'écoulement induites. La variation de la forme de l'écoulement au moment de l'arrêt en fonction de di¤érents paramètres peuvent nous

L. Procédure-d-'essai, essai consiste à étudier l'in ?uence de la présence d'un ferraillage élémentaire placé perpendiculairement à la direction de l'écoulement sur la forme à l'arrêt du matériau. Le ferraillage élémentaire, pouvant être désormais appelé "grille" pour simpli?er l'écriture

.. Etudes-sur-matériaux-réels, 78 6.3.1 Etudes expérimentales sur mortiers et bétons, p.80

. Protocole-d-'essai, pour faire couler le matériau à travers un ferraillage élémentaire d'écartement e variable Comme nous l'avons vu précédemment, le phénomène de blocage des inclusions est e¤ectivement un e¤et géométrique (i.e. le rapport du diamètre des inclusions et l'écartement de deux barres d'acier) mais non pas un e¤et de seuil du matériau. En conséquence, la position du canal n'a pas d'in ?uence sur le résultat d'essai. Nous avons simplement utilisé le canal incliné dans le but d

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