Investigation of failure criterion and plastic potenial of Bangkok clay in π-pleane by torsional shear hollow cylinder apparatus

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.