%0 Journal Article
%T Etude en laboratoire de l¡¯effet du rapport de surconsolidation sur le comportement non drain¨¦ des sols. Laboratory study of overconsolidated ratio of the undrained soil behavior.
%A Djafar Henni A.
%A Arab A.
%A Khelafi H.
%J MATEC Web of Conferences
%D 2012
%I 
%R 10.1051/matecconf/20120205001
%X Dans cet article, on pr¨¦sente une ¨¦tude en laboratoire de l¡¯influence du rapport de surconsolidation sur le comportement non drain¨¦ d¡¯un sable limoneux. L¡¯¨¦tude est bas¨¦e sur des essais triaxiaux non drain¨¦s qui ont ¨¦t¨¦ r¨¦alis¨¦s pour des rapports de surconsolidation (OCR = 1, 2, 4 et 8 ), ¨¤ des fractions de fines particules du m¨¦lange variant entre 0% et 40% .Les essais ont ¨¦t¨¦ effectu¨¦s sur des ¨¦chantillons ayant une densit¨¦ initiale Dr =50 %. L¡¯article est scind¨¦ en deux parties principales. La premi¨¨re partie pr¨¦sente les sols ¨¦tudi¨¦s ; la seconde partie donne une analyse des essais r¨¦alis¨¦s et discute de l¡¯influence du rapport de surconsolidation sur la r¨¦sistance du sol. Les essais montrent que l¡¯augmentation du rapport de surconsolidation (OCR) fait cro tre d¡¯une mani¨¨re consid¨¦rable la r¨¦sistance du sol se traduisant par une augmentation de la dilatance. L¡¯augmentation de la fraction des fines ( Fc) de 0 ¨¤ 40 % augmente la phase de la contractance et par consequent reduit la phase de dilatance du sol ¨¦tudi¨¦. Une d¨¦croissance de l¡¯angle de frottement ¦Õ¡ã est due a une forte teneur en fine (Fc =40%) et ¨¤ OCR = 1 ( sol normalement consolid¨¦). In this paper, we present a laboratory study of the influence of overconsolidation ratio on the undrained behavior of silty sand. This study is based on the undrained triaxial tests which were performed for the overconsolidation ratio at OCR = 1, 2, 4 and 8, with fractions of fines of mixture varying between 0 % and 40 %. Tests were carried out on samples with an relative density Dr= 50% and confinement pressure ¦Ò¡¯c = 100 kPa . The article is divided into two main parts. The first one presents the soils studied and the second one gives an analysis of the results and discusses the influence of overconsolidation ratio on the shear strength of the soil. The tests show that the shear strength of the soil increases with increasing overconsolidation ratio, resulting of in an increase of dilatancy . Increasing the fines content ( Fc ) ranging from 0 to 40 % , increases the phase of contractancy and consequently reducing the phase of dilatancy of the tested soil . A decrease in angle of internal friction (¦Õ ¡ã) is due to a high content of fines (Fc = 40% ) and at OCR = 1 (soil normally consolidated).
%U http://dx.doi.org/10.1051/matecconf/20120205001