4.14.1.4. DruckerPrager¶

nDMaterial('DruckerPrager', matTag, K, G, sigmaY, rho, rhoBar, Kinf, Ko, delta1, delta2, H, theta, density, atmPressure=101e3)

This command is used to construct an multi dimensional material object that has a Drucker-Prager yield criterium.

`matTag` (int)	integer tag identifying material
`K` (float)	bulk modulus
`G` (float)	shear modulus
`sigmaY` (float)	yield stress
`rho` (float)	frictional strength parameter
`rhoBar` (float)	controls evolution of plastic volume change, \(0\le rhoBar \le rho\).
`Kinf` (float)	nonlinear isotropic strain hardening parameter, \(Kinf \ge 0\).
`Ko` (float)	nonlinear isotropic strain hardening parameter, \(Ko \ge 0\).
`delta1` (float)	nonlinear isotropic strain hardening parameter, \(delta1\ge 0\).
`delta2` (float)	tension softening parameter, \(delta2\ge 0\).
`H` (float)	linear hardening parameter, \(H \ge 0\).
`theta` (float)	controls relative proportions of isotropic and kinematic hardening, \(0 \le theta \le 1\).
`density` (float)	mass density of the material
`atmPressure` (float)	optional atmospheric pressure for update of elastic bulk and shear moduli

The material formulations for the DrukerPrager object are:

'ThreeDimensional'
'PlaneStrain'

See theory.