Elasto-Plastic Modeling of Soft Soil Considering Degradation of Stiffness

doi:10.1007/s12204-015-1677-9

摘要/Abstract

关键词: compliant assembly, residual stress, assembly deformation, finite element analysis (FEA)

Abstract:

The stiffness has a large influence on the behavior of soils. Its value is affected by some of the soils properties, such as the over consolidated ratio (OCR), the effective normal stress, and the plasticity index etc. In this paper, the numerical modeling of soft soils was carried out using an improved elasto-plastic S-clay1 model accounting for degradation of stiffness. The relation between the stiffness and the shear strain was established based on a large number of experimental data. The effects of strain-dependent stiffness of normally consolidated soils and over consolidated soils on the stress-strain behavior were studied through a comparison of the simulations with the experimental results of undrained triaxial compression tests. The results show that the behaviors of soils can be well predicted with the improved constitutive model, particularly before the peak stress.

Key words: laterally loaded piles, $m$-method, hydraulic head, land deformation, pumping-recovery, circular excavation, back analysis, horizontal displacement, outage performance, heterogeneous circumstance, magnetic resonance imaging (MRI), sparse representation, non-convex, generalized thresholding, amplify-and-forward (AF), beamforming, channel state information (CSI), power control, cognitive radio, monotone optimization, price, Stackelberg game, fairness, supply chain coordination, dictionary updating, alternating direction method, two-level Bregman method with dictionary updating (TBMDU), admission control scheme, heterogeneity, substitution, service parts, last stock, handover service, high-speed train communication, S-clay1 model, undrained compression test, functionally graded materials, cylindrical sandwich panel, low-velocity water entry, cylinder structure, rectangular sandwich plate, simply supported, free vibration, resting-state brain function network, supercavitating, ventilated, dynamic mesh, pitching, wall effect, model network, connection distance minimization, topological property, anatomical distance, common neighbor, underwater glider, nonlinear control, adaptive backstepping, Lyapunov function, cylinder radius, initial velocity, entry angle, soft soil, strain-dependent modulus, video capsule endoscopy (VCE), frame rate, working hours, in vivo experiment

中图分类号:

TN 435

. [J]. Journal of Shanghai Jiao Tong University(Science), 2015, 20(6): 683-689.

Hao ZHANG, Qiu-shi CHEN, Jin-jian CHEN, Jian-hua WANG. Elasto-Plastic Modeling of Soft Soil Considering Degradation of Stiffness[J]. Journal of Shanghai Jiao Tong University(Science), 2015, 20(6): 683-689.

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