Abstract
This paper presents the result of a field study on the influence of topography on the distribution of the matric suction of the soil in unsaturated slopes subjected to rainfall. The matric suction was measured in the lower, middle and upper parts of planar, ridge-like and gullied slopes before and after two significant rainfall events. Jet-filled tensiometers were used for depths of >1.2 m and the filter paper method at depths of <0.9 m. It was found that in the dry season the matric suction of the soil at a shallow depth in the gullied slope is significantly less than that in the planar and ridge-like slopes while following a rainfall event the decrease in the matric suction is smallest in the gullied slope and greatest in the ridge-like slope, irrespective of the amount of the accumulated precipitation.
Résumé
L’article présente les résultats d’une étude de terrain relative à l’influence de la topographie sur la répartition des succions matricielles dans des pentes non saturées soumises à des pluies. La succion matricielle a été mesurée dans les zones inférieures, moyennes et supérieures de pentes planes, de pentes avec une topographie en crête ou avec une topographie en creux, avant et après deux événements pluvieux importants. Des tensiomètres ont été utilisés aux profondeurs supérieures à 1,2 m et la méthode du papier filtre pour des profondeurs inférieures à 0,9 m. On a trouvé que, pendant la saison sèche, la succion matricielle du sol à faible profondeur dans les pentes à topographie en creux est significativement inférieure à celle du sol dans les pentes planes et les pentes à topographie en crête. Après un événement pluviométrique, la diminution de succion matricielle est plus faible dans les pentes à topographie en creux et plus forte dans les pentes à topographie en crête, quelque soit le total de la pluie tombée.
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Fan, CC., Hsiao, CF. Role of topography in the behavior of the matric suction of unsaturated fill slopes. Bull Eng Geol Environ 71, 61–69 (2012). https://doi.org/10.1007/s10064-011-0383-6
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DOI: https://doi.org/10.1007/s10064-011-0383-6