Yield and Failure Criteria and Generalized Three-Moduli Non-linear Constitutive Model for Soils

摘要

This paper introduces a three-moduli incremental non-linear constitutive model for triaxial stress condition. The yield and failure criterion for the model is discussed. The method for the determination of the three moduli (K,G,J) using conventional triaxial test data is presented. Mathematical functions are suggested for best data fittings. The three-moduli model can consider shear-compression (or shear-dilation) by the coupling modulus J. The three moduli K,G,J are determined using data from an isotropic consolidation test and three CID triaxial shear tests. The computed results using the calibrated KGJ model are in good agreement with the measured test data from three drained triaxial shear tests in constant p'. The three-moduli model for triaxial stress condition is generalized for a 3-D stress state. Physical meanings of the generalized constitutive relationship are discussed with a special attention to the items associated with the coupling modulus J.