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TensorMechanicsPlasticSimpleTester Class Reference

Class that can be used for testing multi-surface plasticity models. More...

#include <TensorMechanicsPlasticSimpleTester.h>

Inheritance diagram for TensorMechanicsPlasticSimpleTester:
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Public Member Functions

 TensorMechanicsPlasticSimpleTester (const InputParameters &parameters)
 
virtual std::string modelName () const override
 
void initialize ()
 
void execute ()
 
void finalize ()
 
virtual unsigned int numberSurfaces () const
 The number of yield surfaces for this plasticity model. More...
 
virtual void yieldFunctionV (const RankTwoTensor &stress, Real intnl, std::vector< Real > &f) const
 Calculates the yield functions. More...
 
virtual void dyieldFunction_dstressV (const RankTwoTensor &stress, Real intnl, std::vector< RankTwoTensor > &df_dstress) const
 The derivative of yield functions with respect to stress. More...
 
virtual void dyieldFunction_dintnlV (const RankTwoTensor &stress, Real intnl, std::vector< Real > &df_dintnl) const
 The derivative of yield functions with respect to the internal parameter. More...
 
virtual void flowPotentialV (const RankTwoTensor &stress, Real intnl, std::vector< RankTwoTensor > &r) const
 The flow potentials. More...
 
virtual void dflowPotential_dstressV (const RankTwoTensor &stress, Real intnl, std::vector< RankFourTensor > &dr_dstress) const
 The derivative of the flow potential with respect to stress. More...
 
virtual void dflowPotential_dintnlV (const RankTwoTensor &stress, Real intnl, std::vector< RankTwoTensor > &dr_dintnl) const
 The derivative of the flow potential with respect to the internal parameter. More...
 
virtual void hardPotentialV (const RankTwoTensor &stress, Real intnl, std::vector< Real > &h) const
 The hardening potential. More...
 
virtual void dhardPotential_dstressV (const RankTwoTensor &stress, Real intnl, std::vector< RankTwoTensor > &dh_dstress) const
 The derivative of the hardening potential with respect to stress. More...
 
virtual void dhardPotential_dintnlV (const RankTwoTensor &stress, Real intnl, std::vector< Real > &dh_dintnl) const
 The derivative of the hardening potential with respect to the internal parameter. More...
 
virtual void activeConstraints (const std::vector< Real > &f, const RankTwoTensor &stress, Real intnl, const RankFourTensor &Eijkl, std::vector< bool > &act, RankTwoTensor &returned_stress) const
 The active yield surfaces, given a vector of yield functions. More...
 
virtual bool useCustomReturnMap () const
 Returns false. You will want to override this in your derived class if you write a custom returnMap function. More...
 
virtual bool useCustomCTO () const
 Returns false. You will want to override this in your derived class if you write a custom consistent tangent operator function. More...
 
virtual bool returnMap (const RankTwoTensor &trial_stress, Real intnl_old, const RankFourTensor &E_ijkl, Real ep_plastic_tolerance, RankTwoTensor &returned_stress, Real &returned_intnl, std::vector< Real > &dpm, RankTwoTensor &delta_dp, std::vector< Real > &yf, bool &trial_stress_inadmissible) const
 Performs a custom return-map. More...
 
virtual RankFourTensor consistentTangentOperator (const RankTwoTensor &trial_stress, Real intnl_old, const RankTwoTensor &stress, Real intnl, const RankFourTensor &E_ijkl, const std::vector< Real > &cumulative_pm) const
 Calculates a custom consistent tangent operator. More...
 
bool KuhnTuckerSingleSurface (Real yf, Real dpm, Real dpm_tol) const
 Returns true if the Kuhn-Tucker conditions for the single surface are satisfied. More...
 

Public Attributes

const Real _f_tol
 Tolerance on yield function. More...
 
const Real _ic_tol
 Tolerance on internal constraint. More...
 

Protected Member Functions

Real yieldFunction (const RankTwoTensor &stress, Real intnl) const override
 The following functions are what you should override when building single-plasticity models. More...
 
RankTwoTensor dyieldFunction_dstress (const RankTwoTensor &stress, Real intnl) const override
 The derivative of yield function with respect to stress. More...
 
Real dyieldFunction_dintnl (const RankTwoTensor &stress, Real intnl) const override
 The derivative of yield function with respect to the internal parameter. More...
 
RankTwoTensor flowPotential (const RankTwoTensor &stress, Real intnl) const override
 The flow potential. More...
 
RankFourTensor dflowPotential_dstress (const RankTwoTensor &stress, Real intnl) const override
 The derivative of the flow potential with respect to stress. More...
 
RankTwoTensor dflowPotential_dintnl (const RankTwoTensor &stress, Real intnl) const override
 The derivative of the flow potential with respect to the internal parameter. More...
 
virtual Real hardPotential (const RankTwoTensor &stress, Real intnl) const
 The hardening potential. More...
 
virtual RankTwoTensor dhardPotential_dstress (const RankTwoTensor &stress, Real intnl) const
 The derivative of the hardening potential with respect to stress. More...
 
virtual Real dhardPotential_dintnl (const RankTwoTensor &stress, Real intnl) const
 The derivative of the hardening potential with respect to the internal parameter. More...
 

Protected Attributes

Real _a
 a More...
 
Real _b
 b More...
 
Real _c
 c More...
 
Real _d
 d More...
 
Real _e
 e More...
 
Real _f
 f More...
 
Real _strength
 strength More...
 

Detailed Description

Class that can be used for testing multi-surface plasticity models.

Yield function = a*stress_yy + b*stress_zz + c*stress_xx + d*(stress_xy + stress_yx)/2 + e*(stress_xz + stress_zx)/2 + f*(stress_yz + stress_zy)/2 - strength No hardening/softening. Associative.

Definition at line 23 of file TensorMechanicsPlasticSimpleTester.h.

Constructor & Destructor Documentation

TensorMechanicsPlasticSimpleTester::TensorMechanicsPlasticSimpleTester ( const InputParameters &  parameters)

Definition at line 55 of file TensorMechanicsPlasticSimpleTester.C.

57  : TensorMechanicsPlasticModel(parameters),
58  _a(getParam<Real>("a")),
59  _b(getParam<Real>("b")),
60  _c(getParam<Real>("c")),
61  _d(getParam<Real>("d")),
62  _e(getParam<Real>("e")),
63  _f(getParam<Real>("f")),
64  _strength(getParam<Real>("strength"))
65 {
66 }
TensorMechanicsPlasticModel(const InputParameters &parameters)

Member Function Documentation

void TensorMechanicsPlasticModel::activeConstraints ( const std::vector< Real > &  f,
const RankTwoTensor &  stress,
Real  intnl,
const RankFourTensor &  Eijkl,
std::vector< bool > &  act,
RankTwoTensor &  returned_stress 
) const
virtualinherited

The active yield surfaces, given a vector of yield functions.

This is used by FiniteStrainMultiPlasticity to determine the initial set of active constraints at the trial (stress, intnl) configuration. It is up to you (the coder) to determine how accurate you want the returned_stress to be. Currently it is only used by FiniteStrainMultiPlasticity to estimate a good starting value for the Newton-Rahson procedure, so currently it may not need to be super perfect.

Parameters
fvalues of the yield functions
stressstress tensor
intnlinternal parameter
Eijklelasticity tensor (stress = Eijkl*strain)
[out]actact[i] = true if the i_th yield function is active
[out]returned_stressApproximate value of the returned stress

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, TensorMechanicsPlasticTensileMulti, TensorMechanicsPlasticMeanCapTC, TensorMechanicsPlasticWeakPlaneShear, and TensorMechanicsPlasticWeakPlaneTensile.

Definition at line 183 of file TensorMechanicsPlasticModel.C.

189 {
190  mooseAssert(f.size() == numberSurfaces(),
191  "f incorrectly sized at " << f.size() << " in activeConstraints");
192  act.resize(numberSurfaces());
193  for (unsigned surface = 0; surface < numberSurfaces(); ++surface)
194  act[surface] = (f[surface] > _f_tol);
195 }
virtual unsigned int numberSurfaces() const
The number of yield surfaces for this plasticity model.
const Real _f_tol
Tolerance on yield function.
RankFourTensor TensorMechanicsPlasticModel::consistentTangentOperator ( const RankTwoTensor &  trial_stress,
Real  intnl_old,
const RankTwoTensor &  stress,
Real  intnl,
const RankFourTensor &  E_ijkl,
const std::vector< Real > &  cumulative_pm 
) const
virtualinherited

Calculates a custom consistent tangent operator.

You may choose to over-ride this in your derived TensorMechanicsPlasticXXXX class.

(Note, if you over-ride returnMap, you will probably want to override consistentTangentOpertor too, otherwise it will default to E_ijkl.)

Parameters
stress_oldtrial stress before returning
intnl_oldinternal parameter before returning
stresscurrent returned stress state
intnlinternal parameter
E_ijklelasticity tensor
cumulative_pmthe cumulative plastic multipliers
Returns
the consistent tangent operator: E_ijkl if not over-ridden

Reimplemented in TensorMechanicsPlasticTensileMulti, TensorMechanicsPlasticDruckerPragerHyperbolic, TensorMechanicsPlasticMeanCapTC, and TensorMechanicsPlasticJ2.

Definition at line 249 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticJ2::consistentTangentOperator(), TensorMechanicsPlasticDruckerPragerHyperbolic::consistentTangentOperator(), TensorMechanicsPlasticMeanCapTC::consistentTangentOperator(), and TensorMechanicsPlasticTensileMulti::consistentTangentOperator().

256 {
257  return E_ijkl;
258 }
RankTwoTensor TensorMechanicsPlasticSimpleTester::dflowPotential_dintnl ( const RankTwoTensor &  stress,
Real  intnl 
) const
overrideprotectedvirtual

The derivative of the flow potential with respect to the internal parameter.

Parameters
stressthe stress at which to calculate the flow potential
intnlinternal parameter
Returns
dr_dintnl(i, j) = dr(i, j)/dintnl

Reimplemented from TensorMechanicsPlasticModel.

Definition at line 115 of file TensorMechanicsPlasticSimpleTester.C.

117 {
118  return RankTwoTensor();
119 }
void TensorMechanicsPlasticModel::dflowPotential_dintnlV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< RankTwoTensor > &  dr_dintnl 
) const
virtualinherited

The derivative of the flow potential with respect to the internal parameter.

Parameters
stressthe stress at which to calculate the flow potential
intnlinternal parameter
[out]dr_dintnldr_dintnl[alpha](i, j) = dr[alpha](i, j)/dintnl

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, and TensorMechanicsPlasticTensileMulti.

Definition at line 134 of file TensorMechanicsPlasticModel.C.

137 {
138  return dr_dintnl.assign(1, dflowPotential_dintnl(stress, intnl));
139 }
virtual RankTwoTensor dflowPotential_dintnl(const RankTwoTensor &stress, Real intnl) const
The derivative of the flow potential with respect to the internal parameter.
RankFourTensor TensorMechanicsPlasticSimpleTester::dflowPotential_dstress ( const RankTwoTensor &  stress,
Real  intnl 
) const
overrideprotectedvirtual

The derivative of the flow potential with respect to stress.

Parameters
stressthe stress at which to calculate the flow potential
intnlinternal parameter
Returns
dr_dstress(i, j, k, l) = dr(i, j)/dstress(k, l)

Reimplemented from TensorMechanicsPlasticModel.

Definition at line 108 of file TensorMechanicsPlasticSimpleTester.C.

110 {
111  return RankFourTensor();
112 }
void TensorMechanicsPlasticModel::dflowPotential_dstressV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< RankFourTensor > &  dr_dstress 
) const
virtualinherited

The derivative of the flow potential with respect to stress.

Parameters
stressthe stress at which to calculate the flow potential
intnlinternal parameter
[out]dr_dstressdr_dstress[alpha](i, j, k, l) = dr[alpha](i, j)/dstress(k, l)

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, and TensorMechanicsPlasticTensileMulti.

Definition at line 120 of file TensorMechanicsPlasticModel.C.

123 {
124  return dr_dstress.assign(1, dflowPotential_dstress(stress, intnl));
125 }
virtual RankFourTensor dflowPotential_dstress(const RankTwoTensor &stress, Real intnl) const
The derivative of the flow potential with respect to stress.
Real TensorMechanicsPlasticModel::dhardPotential_dintnl ( const RankTwoTensor &  stress,
Real  intnl 
) const
protectedvirtualinherited

The derivative of the hardening potential with respect to the internal parameter.

Parameters
stressthe stress at which to calculate the hardening potentials
intnlinternal parameter
Returns
the derivative

Reimplemented in TensorMechanicsPlasticMeanCapTC.

Definition at line 169 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticModel::dhardPotential_dintnlV().

171 {
172  return 0.0;
173 }
void TensorMechanicsPlasticModel::dhardPotential_dintnlV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< Real > &  dh_dintnl 
) const
virtualinherited

The derivative of the hardening potential with respect to the internal parameter.

Parameters
stressthe stress at which to calculate the hardening potentials
intnlinternal parameter
[out]dh_dintnldh_dintnl[alpha] = dh[alpha]/dintnl

Definition at line 175 of file TensorMechanicsPlasticModel.C.

178 {
179  dh_dintnl.resize(numberSurfaces(), dhardPotential_dintnl(stress, intnl));
180 }
virtual unsigned int numberSurfaces() const
The number of yield surfaces for this plasticity model.
virtual Real dhardPotential_dintnl(const RankTwoTensor &stress, Real intnl) const
The derivative of the hardening potential with respect to the internal parameter. ...
RankTwoTensor TensorMechanicsPlasticModel::dhardPotential_dstress ( const RankTwoTensor &  stress,
Real  intnl 
) const
protectedvirtualinherited

The derivative of the hardening potential with respect to stress.

Parameters
stressthe stress at which to calculate the hardening potentials
intnlinternal parameter
Returns
dh_dstress(i, j) = dh/dstress(i, j)

Reimplemented in TensorMechanicsPlasticMeanCapTC.

Definition at line 155 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticModel::dhardPotential_dstressV().

157 {
158  return RankTwoTensor();
159 }
void TensorMechanicsPlasticModel::dhardPotential_dstressV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< RankTwoTensor > &  dh_dstress 
) const
virtualinherited

The derivative of the hardening potential with respect to stress.

Parameters
stressthe stress at which to calculate the hardening potentials
intnlinternal parameter
[out]dh_dstressdh_dstress[alpha](i, j) = dh[alpha]/dstress(i, j)

Definition at line 161 of file TensorMechanicsPlasticModel.C.

164 {
165  dh_dstress.assign(numberSurfaces(), dhardPotential_dstress(stress, intnl));
166 }
virtual unsigned int numberSurfaces() const
The number of yield surfaces for this plasticity model.
virtual RankTwoTensor dhardPotential_dstress(const RankTwoTensor &stress, Real intnl) const
The derivative of the hardening potential with respect to stress.
Real TensorMechanicsPlasticSimpleTester::dyieldFunction_dintnl ( const RankTwoTensor &  stress,
Real  intnl 
) const
overrideprotectedvirtual

The derivative of yield function with respect to the internal parameter.

Parameters
stressthe stress at which to calculate the yield function
intnlinternal parameter
Returns
the derivative

Reimplemented from TensorMechanicsPlasticModel.

Definition at line 95 of file TensorMechanicsPlasticSimpleTester.C.

97 {
98  return 0.0;
99 }
void TensorMechanicsPlasticModel::dyieldFunction_dintnlV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< Real > &  df_dintnl 
) const
virtualinherited

The derivative of yield functions with respect to the internal parameter.

Parameters
stressthe stress at which to calculate the yield function
intnlinternal parameter
[out]df_dintnldf_dintnl[alpha] = df[alpha]/dintnl

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, and TensorMechanicsPlasticTensileMulti.

Definition at line 93 of file TensorMechanicsPlasticModel.C.

96 {
97  return df_dintnl.assign(1, dyieldFunction_dintnl(stress, intnl));
98 }
virtual Real dyieldFunction_dintnl(const RankTwoTensor &stress, Real intnl) const
The derivative of yield function with respect to the internal parameter.
RankTwoTensor TensorMechanicsPlasticSimpleTester::dyieldFunction_dstress ( const RankTwoTensor &  stress,
Real  intnl 
) const
overrideprotectedvirtual

The derivative of yield function with respect to stress.

Parameters
stressthe stress at which to calculate the yield function
intnlinternal parameter
Returns
df_dstress(i, j) = dyieldFunction/dstress(i, j)

Reimplemented from TensorMechanicsPlasticModel.

Definition at line 78 of file TensorMechanicsPlasticSimpleTester.C.

Referenced by flowPotential().

80 {
81  RankTwoTensor df_dsig;
82  df_dsig(1, 1) = _a;
83  df_dsig(2, 2) = _b;
84  df_dsig(0, 0) = _c;
85  df_dsig(0, 1) = _d / 2.0;
86  df_dsig(1, 0) = _d / 2.0;
87  df_dsig(0, 2) = _e / 2.0;
88  df_dsig(2, 0) = _e / 2.0;
89  df_dsig(1, 2) = _f / 2.0;
90  df_dsig(2, 1) = _f / 2.0;
91  return df_dsig;
92 }
void TensorMechanicsPlasticModel::dyieldFunction_dstressV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< RankTwoTensor > &  df_dstress 
) const
virtualinherited

The derivative of yield functions with respect to stress.

Parameters
stressthe stress at which to calculate the yield function
intnlinternal parameter
[out]df_dstressdf_dstress[alpha](i, j) = dyieldFunction[alpha]/dstress(i, j)

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, and TensorMechanicsPlasticTensileMulti.

Definition at line 79 of file TensorMechanicsPlasticModel.C.

82 {
83  df_dstress.assign(1, dyieldFunction_dstress(stress, intnl));
84 }
virtual RankTwoTensor dyieldFunction_dstress(const RankTwoTensor &stress, Real intnl) const
The derivative of yield function with respect to stress.
void TensorMechanicsPlasticModel::execute ( )
inherited

Definition at line 42 of file TensorMechanicsPlasticModel.C.

43 {
44 }
void TensorMechanicsPlasticModel::finalize ( )
inherited

Definition at line 47 of file TensorMechanicsPlasticModel.C.

48 {
49 }
RankTwoTensor TensorMechanicsPlasticSimpleTester::flowPotential ( const RankTwoTensor &  stress,
Real  intnl 
) const
overrideprotectedvirtual

The flow potential.

Parameters
stressthe stress at which to calculate the flow potential
intnlinternal parameter
Returns
the flow potential

Reimplemented from TensorMechanicsPlasticModel.

Definition at line 102 of file TensorMechanicsPlasticSimpleTester.C.

103 {
104  return dyieldFunction_dstress(stress, intnl);
105 }
RankTwoTensor dyieldFunction_dstress(const RankTwoTensor &stress, Real intnl) const override
The derivative of yield function with respect to stress.
void TensorMechanicsPlasticModel::flowPotentialV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< RankTwoTensor > &  r 
) const
virtualinherited

The flow potentials.

Parameters
stressthe stress at which to calculate the flow potential
intnlinternal parameter
[out]rr[alpha] is the flow potential for the "alpha" yield function

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, and TensorMechanicsPlasticTensileMulti.

Definition at line 106 of file TensorMechanicsPlasticModel.C.

109 {
110  return r.assign(1, flowPotential(stress, intnl));
111 }
virtual RankTwoTensor flowPotential(const RankTwoTensor &stress, Real intnl) const
The flow potential.
Real TensorMechanicsPlasticModel::hardPotential ( const RankTwoTensor &  stress,
Real  intnl 
) const
protectedvirtualinherited

The hardening potential.

Parameters
stressthe stress at which to calculate the hardening potential
intnlinternal parameter
Returns
the hardening potential

Reimplemented in TensorMechanicsPlasticMeanCapTC.

Definition at line 142 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticModel::hardPotentialV().

143 {
144  return -1.0;
145 }
void TensorMechanicsPlasticModel::hardPotentialV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< Real > &  h 
) const
virtualinherited

The hardening potential.

Parameters
stressthe stress at which to calculate the hardening potential
intnlinternal parameter
[out]hh[alpha] is the hardening potential for the "alpha" yield function

Definition at line 147 of file TensorMechanicsPlasticModel.C.

150 {
151  h.assign(numberSurfaces(), hardPotential(stress, intnl));
152 }
virtual Real hardPotential(const RankTwoTensor &stress, Real intnl) const
The hardening potential.
virtual unsigned int numberSurfaces() const
The number of yield surfaces for this plasticity model.
void TensorMechanicsPlasticModel::initialize ( )
inherited

Definition at line 37 of file TensorMechanicsPlasticModel.C.

38 {
39 }
bool TensorMechanicsPlasticModel::KuhnTuckerSingleSurface ( Real  yf,
Real  dpm,
Real  dpm_tol 
) const
inherited

Returns true if the Kuhn-Tucker conditions for the single surface are satisfied.

Parameters
yfYield function value
dpmplastic multiplier
dpm_toltolerance on plastic multiplier: viz dpm>-dpm_tol means "dpm is non-negative"

Definition at line 243 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticMohrCoulombMulti::KuhnTuckerOK(), TensorMechanicsPlasticTensileMulti::KuhnTuckerOK(), and TensorMechanicsPlasticModel::returnMap().

244 {
245  return (dpm == 0 && yf <= _f_tol) || (dpm > -dpm_tol && yf <= _f_tol && yf >= -_f_tol);
246 }
const Real _f_tol
Tolerance on yield function.
std::string TensorMechanicsPlasticSimpleTester::modelName ( ) const
overridevirtual

Implements TensorMechanicsPlasticModel.

Definition at line 122 of file TensorMechanicsPlasticSimpleTester.C.

123 {
124  return "SimpleTester";
125 }
unsigned TensorMechanicsPlasticModel::numberSurfaces ( ) const
virtualinherited
bool TensorMechanicsPlasticModel::returnMap ( const RankTwoTensor &  trial_stress,
Real  intnl_old,
const RankFourTensor &  E_ijkl,
Real  ep_plastic_tolerance,
RankTwoTensor &  returned_stress,
Real &  returned_intnl,
std::vector< Real > &  dpm,
RankTwoTensor &  delta_dp,
std::vector< Real > &  yf,
bool &  trial_stress_inadmissible 
) const
virtualinherited

Performs a custom return-map.

You may choose to over-ride this in your derived TensorMechanicsPlasticXXXX class, and you may implement the return-map algorithm in any way that suits you. Eg, using a Newton-Raphson approach, or a radial-return, etc. This may also be used as a quick way of ascertaining whether (trial_stress, intnl_old) is in fact admissible.

For over-riding this function, please note the following.

(1) Denoting the return value of the function by "successful_return", the only possible output values should be: (A) trial_stress_inadmissible=false, successful_return=true. That is, (trial_stress, intnl_old) is in fact admissible (in the elastic domain). (B) trial_stress_inadmissible=true, successful_return=false. That is (trial_stress, intnl_old) is inadmissible (outside the yield surface), and you didn't return to the yield surface. (C) trial_stress_inadmissible=true, successful_return=true. That is (trial_stress, intnl_old) is inadmissible (outside the yield surface), but you did return to the yield surface. The default implementation only handles case (A) and (B): it does not attempt to do a return-map algorithm.

(2) you must correctly signal "successful_return" using the return value of this function. Don't assume the calling function will do Kuhn-Tucker checking and so forth!

(3) In cases (A) and (B) you needn't set returned_stress, returned_intnl, delta_dp, or dpm. This is for computational efficiency.

(4) In cases (A) and (B), you MUST place the yield function values at (trial_stress, intnl_old) into yf so the calling function can use this information optimally. You will have already calculated these yield function values, which can be quite expensive, and it's not very optimal for the calling function to have to re-calculate them.

(5) In case (C), you need to set: returned_stress (the returned value of stress) returned_intnl (the returned value of the internal variable) delta_dp (the change in plastic strain) dpm (the plastic multipliers needed to bring about the return) yf (yield function values at the returned configuration)

(Note, if you over-ride returnMap, you will probably want to override consistentTangentOpertor too, otherwise it will default to E_ijkl.)

Parameters
trial_stressThe trial stress
intnl_oldValue of the internal parameter
E_ijklElasticity tensor
ep_plastic_toleranceTolerance defined by the user for the plastic strain
[out]returned_stressIn case (C): lies on the yield surface after returning and produces the correct plastic strain (normality condition). Otherwise: not defined
[out]returned_intnlIn case (C): the value of the internal parameter after returning. Otherwise: not defined
[out]dpmIn case (C): the plastic multipliers needed to bring about the return. Otherwise: not defined
[out]delta_dpIn case (C): The change in plastic strain induced by the return process. Otherwise: not defined
[out]yfIn case (C): the yield function at (returned_stress, returned_intnl). Otherwise: the yield function at (trial_stress, intnl_old)
[out]trial_stress_inadmissibleShould be set to false if the trial_stress is admissible, and true if the trial_stress is inadmissible. This can be used by the calling prorgram
Returns
true if a successful return (or a return-map not needed), false if the trial_stress is inadmissible but the return process failed

Reimplemented in TensorMechanicsPlasticTensileMulti, TensorMechanicsPlasticMohrCoulombMulti, TensorMechanicsPlasticDruckerPragerHyperbolic, TensorMechanicsPlasticMeanCapTC, and TensorMechanicsPlasticJ2.

Definition at line 216 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticJ2::returnMap(), TensorMechanicsPlasticDruckerPragerHyperbolic::returnMap(), TensorMechanicsPlasticMeanCapTC::returnMap(), TensorMechanicsPlasticMohrCoulombMulti::returnMap(), and TensorMechanicsPlasticTensileMulti::returnMap().

226 {
227  trial_stress_inadmissible = false;
228  yieldFunctionV(trial_stress, intnl_old, yf);
229 
230  for (unsigned sf = 0; sf < numberSurfaces(); ++sf)
231  if (yf[sf] > _f_tol)
232  trial_stress_inadmissible = true;
233 
234  // example of checking Kuhn-Tucker
235  std::vector<Real> dpm(numberSurfaces(), 0);
236  for (unsigned sf = 0; sf < numberSurfaces(); ++sf)
237  if (!KuhnTuckerSingleSurface(yf[sf], dpm[sf], 0))
238  return false;
239  return true;
240 }
virtual unsigned int numberSurfaces() const
The number of yield surfaces for this plasticity model.
bool KuhnTuckerSingleSurface(Real yf, Real dpm, Real dpm_tol) const
Returns true if the Kuhn-Tucker conditions for the single surface are satisfied.
const Real _f_tol
Tolerance on yield function.
virtual void yieldFunctionV(const RankTwoTensor &stress, Real intnl, std::vector< Real > &f) const
Calculates the yield functions.
bool TensorMechanicsPlasticModel::useCustomCTO ( ) const
virtualinherited

Returns false. You will want to override this in your derived class if you write a custom consistent tangent operator function.

Reimplemented in TensorMechanicsPlasticTensileMulti, TensorMechanicsPlasticMeanCapTC, TensorMechanicsPlasticDruckerPragerHyperbolic, and TensorMechanicsPlasticJ2.

Definition at line 210 of file TensorMechanicsPlasticModel.C.

211 {
212  return false;
213 }
bool TensorMechanicsPlasticModel::useCustomReturnMap ( ) const
virtualinherited

Returns false. You will want to override this in your derived class if you write a custom returnMap function.

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, TensorMechanicsPlasticTensileMulti, TensorMechanicsPlasticMeanCapTC, TensorMechanicsPlasticDruckerPragerHyperbolic, and TensorMechanicsPlasticJ2.

Definition at line 204 of file TensorMechanicsPlasticModel.C.

205 {
206  return false;
207 }
Real TensorMechanicsPlasticSimpleTester::yieldFunction ( const RankTwoTensor &  stress,
Real  intnl 
) const
overrideprotectedvirtual

The following functions are what you should override when building single-plasticity models.

The yield function

Parameters
stressthe stress at which to calculate the yield function
intnlinternal parameter
Returns
the yield function

Reimplemented from TensorMechanicsPlasticModel.

Definition at line 69 of file TensorMechanicsPlasticSimpleTester.C.

71 {
72  return _a * stress(1, 1) + _b * stress(2, 2) + _c * stress(0, 0) +
73  _d * (stress(0, 1) + stress(1, 0)) / 2.0 + _e * (stress(0, 2) + stress(2, 0)) / 2.0 +
74  _f * (stress(1, 2) + stress(2, 1)) / 2.0 - _strength;
75 }
void TensorMechanicsPlasticModel::yieldFunctionV ( const RankTwoTensor &  stress,
Real  intnl,
std::vector< Real > &  f 
) const
virtualinherited

Calculates the yield functions.

Note that for single-surface plasticity you don't want to override this - override the private yieldFunction below

Parameters
stressthe stress at which to calculate the yield function
intnlinternal parameter
[out]fthe yield functions

Reimplemented in TensorMechanicsPlasticMohrCoulombMulti, and TensorMechanicsPlasticTensileMulti.

Definition at line 64 of file TensorMechanicsPlasticModel.C.

Referenced by TensorMechanicsPlasticModel::returnMap().

67 {
68  f.assign(1, yieldFunction(stress, intnl));
69 }
virtual Real yieldFunction(const RankTwoTensor &stress, Real intnl) const
The following functions are what you should override when building single-plasticity models...

Member Data Documentation

Real TensorMechanicsPlasticSimpleTester::_a
protected

a

Definition at line 44 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by dyieldFunction_dstress(), and yieldFunction().

Real TensorMechanicsPlasticSimpleTester::_b
protected

b

Definition at line 47 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by dyieldFunction_dstress(), and yieldFunction().

Real TensorMechanicsPlasticSimpleTester::_c
protected

c

Definition at line 50 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by dyieldFunction_dstress(), and yieldFunction().

Real TensorMechanicsPlasticSimpleTester::_d
protected

d

Definition at line 53 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by dyieldFunction_dstress(), and yieldFunction().

Real TensorMechanicsPlasticSimpleTester::_e
protected

e

Definition at line 56 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by dyieldFunction_dstress(), and yieldFunction().

Real TensorMechanicsPlasticSimpleTester::_f
protected

f

Definition at line 59 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by dyieldFunction_dstress(), and yieldFunction().

const Real TensorMechanicsPlasticModel::_f_tol
inherited
const Real TensorMechanicsPlasticModel::_ic_tol
inherited

Tolerance on internal constraint.

Definition at line 174 of file TensorMechanicsPlasticModel.h.

Real TensorMechanicsPlasticSimpleTester::_strength
protected

strength

Definition at line 62 of file TensorMechanicsPlasticSimpleTester.h.

Referenced by yieldFunction().


The documentation for this class was generated from the following files: