double
RankinePlasticMaterial :: computeYieldValueAt(GaussPoint *gp, int isurf, const FloatArray &stressVector,
const FloatArray &stressSpaceHardeningVars)
{
FloatArray princStress(3);
this->computePrincipalValues(princStress, stressVector, principal_stress);
return princStress.at(isurf) - this->k;
}
void
RankinePlasticMaterial :: computeStressGradientVector(FloatArray &answer, functType ftype, int isurf, GaussPoint *gp, const FloatArray &stressVector,
const FloatArray &stressSpaceHardeningVars)
{
FloatArray princStress(3);
FloatMatrix t(3, 3);
// compute principal stresses and their directions
this->computePrincipalValDir(princStress, t, stressVector, principal_stress);
//derivation through stress transformation. The transformation matrix is stored in t.
answer.resize(6);
answer.at(1) = t.at(1, isurf) * t.at(1, isurf);//xx = 11
answer.at(2) = t.at(2, isurf) * t.at(2, isurf);//yy = 22
answer.at(3) = t.at(3, isurf) * t.at(3, isurf);//zz = 33
answer.at(4) = t.at(2, isurf) * t.at(3, isurf);//yz = 23
answer.at(5) = t.at(1, isurf) * t.at(3, isurf);//xz = 13
answer.at(6) = t.at(1, isurf) * t.at(2, isurf);//xy = 12
//crossSection->giveReducedCharacteristicVector(answer, gp, fullAnswer);
}
double
DruckerPragerCutMat :: computeYieldValueAt(GaussPoint *gp, int isurf, const FloatArray &stressVector, const FloatArray &strainSpaceHardeningVariables)
{
//strainSpaceHardeningVariables = kappa
if ( isurf <= 3 ) { //Rankine, surfaces 1,2,3
FloatArray princStress(3);
this->computePrincipalValues(princStress, stressVector, principal_stress);
return princStress.at(isurf) - this->sigT;
} else { //Drucker-Prager, surface 4
double volumetricStress;
double DPYieldStressInShear = tau0 + H *strainSpaceHardeningVariables.at(4);
double JTwo;
//MaterialMode mmode = gp->giveMaterialMode();
MaterialMode mmode = _3dMat;
StressVector stressVector1(stressVector, mmode); //convert from array
StressVector deviatoricStress(mmode);
stressVector1.computeDeviatoricVolumetricSplit(deviatoricStress, volumetricStress);
JTwo = deviatoricStress.computeSecondInvariant();
return 3. * alpha * volumetricStress + sqrt(JTwo) - DPYieldStressInShear;
}
}
//associated and nonassociated flow rule
void
DruckerPragerCutMat :: computeStressGradientVector(FloatArray &answer, functType ftype, int isurf, GaussPoint *gp, const FloatArray &stressVector, const FloatArray &stressSpaceHardeningVars)
{
FloatArray princStress(3);
FloatMatrix t(3, 3);
// compute principal stresses and their directions
this->computePrincipalValDir(princStress, t, stressVector, principal_stress);
// derivation through stress transformation matrix. The transformation matrix is stored in t columnwise
answer.resize(6);
if ( isurf <= 3 ) { //Rankine associated
answer.at(1) = t.at(1, isurf) * t.at(1, isurf); //xx = 11
answer.at(2) = t.at(2, isurf) * t.at(2, isurf); //yy = 22
answer.at(3) = t.at(3, isurf) * t.at(3, isurf); //zz = 33
answer.at(4) = t.at(2, isurf) * t.at(3, isurf); //yz = 23
answer.at(5) = t.at(1, isurf) * t.at(3, isurf); //xz = 13
answer.at(6) = t.at(1, isurf) * t.at(2, isurf); //xy = 12
} else { //DP nonassociated
//MaterialMode mmode = gp->giveMaterialMode();
MaterialMode mmode = _3dMat;
StressVector stressVector1(stressVector, mmode); //convert from array
StressVector deviatoricStress(mmode);
double sqrtJTwo, volumetricStress;
stressVector1.computeDeviatoricVolumetricSplit(deviatoricStress, volumetricStress);
sqrtJTwo = sqrt( deviatoricStress.computeSecondInvariant() );
answer.at(1) = alphaPsi + deviatoricStress.at(1) / 2. / sqrtJTwo;
answer.at(2) = alphaPsi + deviatoricStress.at(2) / 2. / sqrtJTwo;
answer.at(3) = alphaPsi + deviatoricStress.at(3) / 2. / sqrtJTwo;
answer.at(4) = stressVector1.at(4) / sqrtJTwo;
answer.at(5) = stressVector1.at(5) / sqrtJTwo;
answer.at(6) = stressVector1.at(6) / sqrtJTwo;
}
}
