Nonlinear analysis of fluid saturated soil and rock under complex hydromechanical loading on the base of poroplastic models

The elastic-plastic model is adopted to simulate the behavior of saturated porous material under mechanical and hydraulic loading. Linear strains are calculated with Biot coupled poroelastic equations. Transition to the plastic state is determined by Mohr-Coulomb or Drucker-Prager criterion in Terzaghi effective stress space. Multisurface theory of plasticity algorithms are used for integration of nonlinear constitutive equations. The results of computations show a good agreement in comparison with available experimental data.