.. include:: sub.txt ================== PM4Sand ================== .. function:: nDMaterial('PM4Sand', matTag, D_r, G_o, h_po, Den, P_atm, h_o, e_max, e_min, n_b, n_d, A_do, z_max, c_z, c_e, phi_cv, nu, g_degr, c_dr, c_kaf, Q_bolt, R_bolt, m_par, F_sed, p_sed) :noindex: This command is used to construct a 2-dimensional PM4Sand material. ================================ =========================================================================== ``matTag`` |int| integer tag identifying material ``D_r`` |float| Relative density, in fraction ``G_o`` |float| Shear modulus constant ``h_po`` |float| Contraction rate parameter ``Den`` |float| Mass density of the material ``P_atm`` |float| Optional, Atmospheric pressure ``h_o`` |float| Optional, Variable that adjusts the ratio of plastic modulus to elastic modulus ``e_max`` |float| Optional, Maximum and minimum void ratios ``e_min`` |float| Optional, Maximum and minimum void ratios ``n_b`` |float| Optional, Bounding surface parameter, :math:`n_b \ge 0` ``n_d`` |float| Optional, Dilatancy surface parameter :math:`n_d \ge 0` ``A_do`` |float| Optional, Dilatancy parameter, will be computed at the time of initialization if input value is negative ``z_max`` |float| Optional, Fabric-dilatancy tensor parameter ``c_z`` |float| Optional, Fabric-dilatancy tensor parameter ``c_e`` |float| Optional, Variable that adjusts the rate of strain accumulation in cyclic loading ``phi_cv`` |float| Optional, Critical state effective friction angle ``nu`` |float| Optional, Poisson's ratio ``g_degr`` |float| Optional, Variable that adjusts degradation of elastic modulus with accumulation of fabric ``c_dr`` |float| Optional, Variable that controls the rotated dilatancy surface ``c_kaf`` |float| Optional, Variable that controls the effect that sustained static shear stresses have on plastic modulus ``Q_bolt`` |float| Optional, Critical state line parameter ``R_bolt`` |float| Optional, Critical state line parameter ``m_par`` |float| Optional, Yield surface constant (radius of yield surface in stress ratio space) ``F_sed`` |float| Optional, Variable that controls the minimum value the reduction factor of the elastic moduli can get during reconsolidation ``p_sed`` |float| Optional, Mean effective stress up to which reconsolidation strains are enhanced ================================ =========================================================================== The material formulations for the PM4Sand object are: * ``'PlaneStrain'`` See als `here `_ References R.W.Boulanger, K.Ziotopoulou. "PM4Sand(Version 3.1): A Sand Plasticity Model for Earthquake Engineering Applications". Report No. UCD/CGM-17/01 2017