TY - JOUR
T1 - Nonstationary flow surface theory for modeling the viscoplastic behaviors of soils
AU - Ferrari, Alessio
AU - Ferrari, Alessio
AU - Qiao, Yafei
AU - Laloui, Lyesse
AU - Ding, Wenqi
PY - 2016
Y1 - 2016
N2 - This paper presents a three-dimensional elastic viscoplastic model that can describe the time-dependent behaviors of soft clays. The constitutive model is formulated based on the nonstationary flow surface theory and incorporates new developments, including (i) an improved definition of the nonstationary flow surface that is capable of capturing the stress-strain behaviors under different loading paths, (ii) a unique stress-strain-viscoplastic-strain-rate equation that is able to explicitly describe the nonstationary flow surface, and (iii) a final stable state concept that identifies the final equilibrium state at the end of creep and stress relaxation, which is also used to simplify the loading criteria. The consistency condition is validated for the proposed model, and the viscoplastic multipliers are calculated by solving the consistency equations. The model performance is investigated and validated via simulation of both oedometer and triaxial tests. The numerical results demonstrate that the proposed model is able to reproduce the main viscoplastic behaviors of soils, including creep, undrained creep rupture, stress relaxation, rate effect and accumulated effect.
AB - This paper presents a three-dimensional elastic viscoplastic model that can describe the time-dependent behaviors of soft clays. The constitutive model is formulated based on the nonstationary flow surface theory and incorporates new developments, including (i) an improved definition of the nonstationary flow surface that is capable of capturing the stress-strain behaviors under different loading paths, (ii) a unique stress-strain-viscoplastic-strain-rate equation that is able to explicitly describe the nonstationary flow surface, and (iii) a final stable state concept that identifies the final equilibrium state at the end of creep and stress relaxation, which is also used to simplify the loading criteria. The consistency condition is validated for the proposed model, and the viscoplastic multipliers are calculated by solving the consistency equations. The model performance is investigated and validated via simulation of both oedometer and triaxial tests. The numerical results demonstrate that the proposed model is able to reproduce the main viscoplastic behaviors of soils, including creep, undrained creep rupture, stress relaxation, rate effect and accumulated effect.
KW - Computer Science Applications1707 Computer Vision and Pattern Recognition
KW - Constitutive model
KW - Final stable state concept
KW - Geotechnical Engineering and Engineering Geology
KW - Nonstationary flow surface theory
KW - Rate dependent
KW - Time softening
KW - Viscoplasticity
KW - Computer Science Applications1707 Computer Vision and Pattern Recognition
KW - Constitutive model
KW - Final stable state concept
KW - Geotechnical Engineering and Engineering Geology
KW - Nonstationary flow surface theory
KW - Rate dependent
KW - Time softening
KW - Viscoplasticity
UR - http://hdl.handle.net/10447/263277
UR - http://www.elsevier.com/inca/publications/store/4/0/5/8/9/3/index.htt
M3 - Article
VL - 76
SP - 105
EP - 119
JO - Computers and Geotechnics
JF - Computers and Geotechnics
SN - 0266-352X
ER -