Limits of isotropic plastic deformation of Bangkok clay

P. Evesque: Lab MSSM, UMR 8579 CNRS, Ecole Centrale Paris, 92295 Châtenay-Malabry, France , evesque@mssmat.ecp.fr

Abstract: A model assuming incremental plastic isotropic response has been recently proposed to model the deformation of isotropic packing of grains, in the small-strain range. It is used here on over-consolidated remould clay, to interpret the small-strain range behaviour obtained in [1,2] on Bangkok clay. The data published in [1,2] at constant volume are also used here to measure the size of the domain of validity in the (q/(M’p),p/p_o) plane, where p_o is the over-consolidation isotropic pressure, p=(s₁+ s₂+ s₃)/3 is the mean stress and q the deviatoric stress, q= s₁- s₃ . So, it is shown that the model works also for clay. This enlarges the application domain of model [3,4] to soft clay with OCR larger than 1.2 to 1.5.

Pacs # : 45.70.-n ; 62.20.Fe ; 83.80.Fg, 83.80.Hj

poudres & grains 14 (1), 4-7 (janvier 2004)