4.15.1.13. PM4Sand

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)

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, \(n_b \ge 0\)
n_d (float) Optional, Dilatancy surface parameter \(n_d \ge 0\)
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