Creep Deformation of Clays

Measurement of stress-strain-time behavior of clays was made by means of drained triaxial tests. Undisturbed samples of glacial deposits near Cleveland, a plastic clay from Nevada, and remolded Grundite were used for the tests. The results led to a creep law of the form ϵ=Ctn in which ϵ=strain, t=time, and C and n are material constants. The effects of incremental loading, anisotropic consolidation, and stress-state were also investigated. The measured properties of the Cleveland soils were used to compute the displacements around an excavation near Cleveland. Comparison of measured and computed displacements showed that the computed and measured final displacements are of the same order of magnitude. However, the measured creep rate is considerably higher than the computed values.