const Vector &BkStressLimSurface2D::getEquiPlasticStiffness()
{
double kp_kin_x = kinMatX->getTrialPlasticStiffness();
double kp_kin_y = kinMatY->getTrialPlasticStiffness();
double kp_iso_x = isoMatXPos->getTrialPlasticStiffness();
double kp_iso_y = isoMatYPos->getTrialPlasticStiffness();
if(!defPosX)
kp_iso_x = isoMatXNeg->getTrialPlasticStiffness();
if(!defPosY)
kp_iso_y = isoMatYNeg->getTrialPlasticStiffness();
// opserr << *isoMatYPos;
// opserr << *isoMatXPos;
v2(0) =isotropicRatio*kp_iso_x + kinematicRatio*kp_kin_x;
v2(1) =isotropicRatio*kp_iso_y + kinematicRatio*kp_kin_y;
if(isotropicFactor(0) <=minIsoFactor)
v2(0) = 0;
if(isotropicFactor(1) <=minIsoFactor)
v2(1) = 0;
return v2;
}
XC::NullEvolution::NullEvolution(int tag, double isox, double isoy)
:YS_Evolution(tag, nullptr_EVOL_CLASS_TAG, 0.0, 0.0, 2, 0.0, 0.0)
{
isotropicFactor(0) = isox;
isotropicFactor(1) = isoy;
isotropicFactor_hist(0) = isox;
isotropicFactor_hist(1) = isoy;
}
YS_Evolution2D::YS_Evolution2D(int tag, int classtag,
double min_iso_factor,
double iso_ratio, double kin_ratio)
:YS_Evolution(tag, classtag, iso_ratio, kin_ratio, 2),
minIsoFactor(min_iso_factor), softening(false)
{
// sumPlasticDeformX = 0;
// sumPlasticDeformX_hist = 0;
// sumPlasticDeformY = 0;
// sumPlasticDeformY_hist = 0;
isotropicFactor(0) = 1;
isotropicFactor(1) = 1;
isotropicFactor_hist(0) = 1;
isotropicFactor_hist(1) = 1;
}
/** No descriptions */
XC::YS_Evolution * XC::NullEvolution::getCopy()
{
XC::NullEvolution *copy=0;
if(dimension == 1)
copy = new NullEvolution(getTag(), isotropicFactor(0));
else if(dimension == 2)
copy = new NullEvolution(getTag(), isotropicFactor(0), isotropicFactor(1));
else if(dimension == 3)
copy = new NullEvolution(getTag(), isotropicFactor(0), isotropicFactor(1), isotropicFactor(2));
else
copy = 0;
return copy;
}
int YS_Evolution2D::evolveSurface(YieldSurface_BC *ys, double lamda,
Vector &G, Vector &F_Surface, int flag)
{
// first and fore-most:
tmpYSPtr = ys;
// int loc = ys->ele_Location;
// opserr << " evolve surface [" << opserr << loc << "]\n";
// opserr << *ys;
//freezeEvolution = false; -> have set this in commitState -> don't change
// first save the vlues on stack
// static vectors could get reallocated elsewhere
Vector f_sur(2);
f_sur(0) = F_Surface(0);
f_sur(1) = F_Surface(1);
Vector gl(2);
gl(0) = G(0);
gl(1) = G(1);
setTrialPlasticStrains(lamda, f_sur, gl);
if(freezeEvolution)
return 0;
//deformable = true;
double kinX = gl(0)*getKinPlasticStiffness(0)/ys->getCap(0);
double kinY = gl(1)*getKinPlasticStiffness(1)/ys->getCap(1);
double isoX = gl(0)*getIsoPlasticStiffness(0)/ys->getCap(0);
double isoY = gl(1)*getIsoPlasticStiffness(1)/ys->getCap(1);
// opserr << "isoX = " << isoX << ", isoY = " << isoY << endln;
// kinematic hardening
double lamda_kin = kinematicRatio*lamda;
double dfx_kin = lamda_kin*kinX;
double dfy_kin = lamda_kin*kinY;
// isotropic hardening
double lamda_iso = isotropicRatio*lamda;
double dfx_iso = lamda_iso*isoX;
double dfy_iso = lamda_iso*isoY;
double dfx_total = dfx_kin + dfx_iso;
double dfy_total = dfy_kin + dfy_iso;
double fx_new = f_sur(0) + dfx_total;
double fy_new = f_sur(1) + dfy_total;
double fx_iso_new = f_sur(0) + dfx_iso;
double fy_iso_new = f_sur(1) + dfy_iso;
// check 1: for cross-over -> same as: |F_sur + df| > |F_sur| && Kp < 0
// sign change
//cout << "f_sur = " << f_sur(0) << ", f new = " << fx_new << endln;
bool ys_harden = true;
toOriginalCoord(fx_new, fy_new);
if(ys->getDrift(fx_new, fy_new) < 0)
ys_harden = false;
bool iso_harden = true;
toOriginalCoord(fx_iso_new, fy_iso_new);
if(ys->getDrift(fx_iso_new, fy_iso_new) < 0)
iso_harden = false;
if(!ys_harden && (sign(f_sur(0)) != sign(fx_new))) // risky to use for fy -> P
{
// need to fix this
dfx_iso = 0.0;
dfx_kin = 0.0;
opserr << "Condition happened..\n";
opserr << *ys;
freezeEvolution = true;
//cerr << "F_Surface(0) = " << f_sur(0) << ", F_New = " << fx_new << endln;
//cin.get();
// if(!deformable) //nothing to do
// return anyway for now
{
return 0;
// dfy_iso = 0.0;
// dfy_kin = 0.0;
}
}
if(!ys_harden && (kinematicRatio != kinematicRatio_shrink)
&& (isotropicRatio != isotropicRatio_shrink) )
{
double kinRatio = kinematicRatio_shrink;
double isoRatio = isotropicRatio_shrink;
// here it might be a good idea to redo the above step
// will not make difference for peak-oriented but for
// others may cause convergence problems (Kp_iso != Kp_kin)
// what if its not softening anymore?
lamda_iso = isoRatio*lamda;
dfx_iso = lamda_iso*isoX;
dfy_iso = lamda_iso*isoY;
lamda_kin = kinRatio*lamda;
dfx_kin = lamda_kin*kinX;
dfy_kin = lamda_kin*kinY;
dfx_total = dfx_kin + dfx_iso;
dfy_total = dfy_kin + dfy_iso;
fx_new = f_sur(0) + dfx_total;
fy_new = f_sur(1) + dfy_total;
toOriginalCoord(fx_new, fy_new);
if(ys->getDrift(fx_new, fy_new) > 0)
{
opserr << "oops: YS_Evolution2D::evolveSurface() - softens->hardens\n";
ys_harden = true;
}
}
// Update the isotropicFactor vector
/*
// This way does not work!
int x_grow = 1;
if(fabs(f_sur(0) + dfx_iso) < fabs(f_sur(0)))
{
// opserr << "Softening!\n";
x_grow = -1;
}
int y_grow = 1;
if(fabs(f_sur(1) + dfy_iso) < fabs(f_sur(1)))
y_grow = -1;
*/
int x_grow = 1, y_grow = 1;
if(getIsoPlasticStiffness(0) < 0)
x_grow = -1;
if(getIsoPlasticStiffness(1) < 0)
y_grow = -1;
if(evolDebug)
{
opserr << "F_Surface Vector: " << f_sur;
opserr << "Fx_new = " << fx_new << ", Fy_new = " << fy_new << endln;
opserr << "Gradient: " << gl;
opserr << "KpxIso = " << getIsoPlasticStiffness(0) << ", KpyIso = " << getIsoPlasticStiffness(1) << endln;
opserr << "F_surf(1) = " << f_sur(1) << ", dfy_iso = " << dfy_iso << endln;
opserr << "x_grow = " << x_grow << ", y_grow = " << y_grow << endln;
opserr << "---------------------------------------------------------" << endln;
}
Vector mgnf(2);
mgnf = isotropicFactor_hist;
if(flag==1)
mgnf = isotropicFactor;
Vector delMag(2);
if(deformable)
{
delMag(0) = x_grow*fabs(dfx_iso);
delMag(1) = y_grow*fabs(dfy_iso);
}
else
{
double dR = sqrt(dfx_iso*dfx_iso + dfy_iso*dfy_iso);
if(!iso_harden)
dR = -1*dR;
delMag(0) = dR;
delMag(1) = dR;
}
Vector isoFact = mgnf + delMag;
//check 2: For min isotropic factor
if( (isotropicFactor(0) + delMag(0)) <= minIsoFactor)
{
delMag(0) = 0.0;
dfx_kin = 0.0;
freezeEvolution = true;
if(!deformable)// nothing to do
return 0;
}
if( (isotropicFactor(1) + delMag(1)) <= minIsoFactor)
{
delMag(1) = 0.0;
dfy_kin = 0.0;
freezeEvolution = true;
if(!deformable)
return 0;
}
// update the translation vector
double fx_aim = f_sur(0) + dfx_kin;
double fy_aim = f_sur(1) + dfy_kin;
//cout << "YS_Evolution2D - F_Surface = " << F_Surface;
toOriginalCoord(fx_aim, fy_aim);
Vector f_aim(2);
f_aim(0) = fx_aim;
f_aim(1) = fy_aim;
v2 = getEvolDirection(f_aim);
Vector df_kin = ys->translationTo(f_aim, v2);
// correct for isotropic factor
Vector trans(2);
trans = translate_hist;
if(flag==1)
trans = translate;
// Update the quantities
translate(0) = trans(0) + df_kin(0)*isotropicFactor(0);
translate(1) = trans(1) + df_kin(1)*isotropicFactor(1);
isotropicFactor = mgnf + delMag;
return 0;
}
