Abstract
Soil cohesion changes with the moisture state of a soil. This paper presents an empirical equation to predict the cohesive component in the shear strength of unsaturated residual soils as an exponential function of volumetric water content. The formulation originated from a multiple linear-regression analysis for data sets obtained from shear tests using undisturbed soils with varying moisture contents. The empirical equations can realistically predict the reduction in soil cohesion due to wetting (R 2=0.88, 0.93). The methodology described in this paper provides a convenient alternative to the quantitative estimation of unsaturated shear strength, especially in an engineering practice such as a slope stability analysis as no matrix suction data are required.
Résumé
La cohésion des sols change avec leur teneur en eau. L’article présente une relation empirique permettant d’exprimer la valeur de cohésion de sols résiduels non saturés comme une fonction exponentielle de la teneur en eau volumétrique. La formulation résulte d’une analyse par régression linéaire de séries de données provenant d’essais de cisaillement sur des sols non remaniés présentant diverses teneurs en eau. Les équations obtenues sont capables de représenter correctement la diminution de la cohésion résultant de l’humidification d’un sol. La méthodologie présentée dans l’article permet d’obtenir une estimation de la résistance au cisaillement en conditions non saturées, en particulier pour des applications relatives à des analyses de stabilité des pentes, sans faire appel à des données concernant l’état de succion du sol.
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Matsushi, Y., Matsukura, Y. Cohesion of unsaturated residual soils as a function of volumetric water content. Bull Eng Geol Environ 65, 449–455 (2006). https://doi.org/10.1007/s10064-005-0035-9
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DOI: https://doi.org/10.1007/s10064-005-0035-9