Abstract:
This paper presents an experimental investigation on the failure criterion and plastic potential of Bangkok Clay in π-plane. The results of undrained torsional shear hollow cylinder test on undisturbed Bangkok Clay specimens with various principal stress directions and magnitudes of intermediate principal stress are presented.The obtained stress-strain behaviors show clear evidences of anisotropic characteristics
of Bangkok Clay. Both failure criterion and plastic potential of Bangkok Clay in π-plane are found to be isotropic and of circular shape which implies a Drucker-Prager type and associated flow rule.