Mohr-Coulomb Model with Tension Cut Off
The original formulation of the Mohr-Coulomb material model is extended by introducing the Rankine type of plasticity condition, see Figure (a), allowing for the reduction of tensile strength of soil, which in case of standard Mohr-Coulomb model is given by c*cotgφ, where c is the cohesion and φ the angle of internal friction. This value can be reduced by specifying the value of tensile strength σt as evident from Figure (b). If σt > c*cotgφ the program automatically sets σt = c*cotgφ. This model can be used if the advanced program options are on.
a) Projection of the Rankine yield condition in the deviatoric plane, b) Projection of the extended Mohr-Coulomb yield condition into the σ1, σ3 plane