The stress–strain behaviour and critical state parameters of an unsaturated granular fill material under different suctions

According to Mengzi expansive soil, consolidated drained tests and undrained tests are carried on under saturated and remoulded conditions. The stress-strain characteristics of saturated soil are researched systematically under different confining pressure, initial dry density, initial water content, shearing rate and drainage condition. The inherent unity of diversity of shearing strength for the same samples measured by different experimental methods is indicated according to the normalization of critical state test results. And the failure lines in p ‘- q - ν space of remoulded saturated expansive soil under consolidated drained and undrained conditions are attained. The hyperbolic curve model can fit well the weak hardening stress-strain curves and the exponential curve model can fit the weak softening stress-strain curves. The test results can provide technical parameters and theoretical help for shearing strength variation of slope during rainfall and strength state of soil structure in normal water level.

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Boundary conditions, anisotropy and sample shape effects onthe stress-strain behaviour of sand in triaxial compression and plane strain

Géotechnique ◽

10.1680/geot.1975.25.2.333 ◽

1975 ◽

Vol 25 (2) ◽

pp. 333-356 ◽

Cited By ~ 22

Author(s):

G. E. Green ◽

D. E Reades

Keyword(s):

Boundary Conditions ◽

Plane Strain ◽

Triaxial Compression ◽

Stress Strain ◽

Sample Shape ◽

Strain Behaviour ◽

Shape Effects

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A New Nonlinear Stress-Strain Model for Soils at Various Strain Levels

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.631-632.782 ◽

2013 ◽

Vol 631-632 ◽

pp. 782-788

Author(s):

Cheng Chen ◽

Zheng Ming Zhou

Keyword(s):

Compression Test ◽

Triaxial Compression ◽

Small Strain ◽

Empirical Formulas ◽

Stress Strain ◽

Strain Behaviour ◽

Proposed Model ◽

Nonlinear Stress ◽

London Clay ◽

Strain Model

Soils have nonlinear stiffness and develops irrecoverable strains even at very small strain levels. Accurate modeling of stress-strain behaviour at various strain levels is very important for predicting the deformation of soils. Some existing stress-strain models are reviewed and evaluated firstly. And then a new simple non-linear stress-strain model is proposed. Four undetermined parameters involved in the proposed model can be obtained through maximum Young’s module, deformation module, and limit deviator stress and linearity index of soils that can be measured from experiment directly or calculated by empirical formulas indirectly. The effectiveness of the proposed stress-strain model is examined by predicting stress-strain curves measured in plane-strain compression test on Toyota sand and undrained triaxial compression test on London clay. The fitting results of the proposed model are in good agreement with experimental data, which verify the effectiveness of the model.

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