By using a suction-controllable dynamic triaxial testing system USTX-2000 for the unsaturated and saturated soils developed by GCTS Company, the dynamic deformation characteristics of unsaturated silt have been studied with suctions being controlled. Test results of dynamic deformation characteristics are obtained including the skeleton curve of dynamic stress-strain relation, dynamic modulus, and damping ratio. The following results are obtained. Skeleton curves of unsaturated silt under suction control are hyperbolic under dynamic loading, and the larger the suction, the higher the skeleton curves. The dynamic modulus of unsaturated silt increases with the increasing suction, and the effect of suction on dynamic modulus is less than that of the confining pressure. The damping ratio of unsaturated silt decreases with the increasing suction, and the effect of suction on the damping ratio is less than that of the confining pressure. Changes in the skeleton curves of dynamic stress-strain relation, dynamic modulus and damping ratio with the suction can be explained by the change in the average skeleton stress.
JIA Lei, SUN De-an, HAO Fei
. Dynamic deformation characteristics of unsaturated silt under suction control[J]. Journal of Shanghai University, 2015
, 21(1)
: 117
-127
.
DOI: 10.3969/j.issn.1007-2861.2014.01.013
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