The deformation characteristics of clay are closely related to the stress path
which affects the safety of related projects directly. Aiming at the silty clay from a embankment slope beside Three Gorges Reservoir
two groups of repeated isotropic loading-unloading tests are completed by stress path controlling equipment
which reveals the cyclic response of soil volumetric deformation. The reloading processes can be described as curves of first gentle and then steep
which induces unrecoverable plastic deformations even when the stresses are in the range of pre-consolidated pressure
and the deformation rate decreases gradually with the increase of loading-unloading cycles. Then
on the basis of the characteristics of test curves
a mathematical model is established to describe the relationship of re-consolidation coefficients with the cycle number and the stress state. The presented model can simulate the volumetric cyclic response due to repeated isotropic loading and unloading and predict the deformation developments due to more reloading cycle. Moreover
the calculation results can also provide references for analyzing and predicting the continuous plastic deformation well.
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references
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Related Author
CHEN Tiannan
DENG Huafeng
LI Jianlin
LIU Lipeng
CHEN Xingzhou
LI Tao
乔亚飞
Related Institution
Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education
Key Laboratory of Construction and Safety of Water Engineering of the Ministry of Water Resources, China Institute of Water Resources and Hydropower Research
College of Architecture and Civil Engineering,Xi'an University of Science and Technology, Xi 'an