This class computes a creep strain increment associated with a linear viscoelastic model contained in a LinearViscoelasticityBase material. More...

#include <LinearViscoelasticStressUpdate.h>

Inheritance diagram for LinearViscoelasticStressUpdate:

[legend]

Public Member Functions
	LinearViscoelasticStressUpdate (const InputParameters &parameters)

virtual void	updateState (RankTwoTensor &strain_increment, RankTwoTensor &inelastic_strain_increment, const RankTwoTensor &rotation_increment, RankTwoTensor &stress_new, const RankTwoTensor &stress_old, const RankFourTensor &elasticity_tensor, const RankTwoTensor &elastic_strain_old, bool compute_full_tangent_operator, RankFourTensor &tangent_operator) override
	Computes the new creep strain, and removes the creep contribution from the elastic strains and stress. More...

virtual void	propagateQpStatefulProperties () override
	Reimplemented from StressUpdateBase. More...

virtual bool	requiresIsotropicTensor () override
	Does the model require the elasticity tensor to be isotropic? More...

void	setQp (unsigned int qp)
	Sets the value of the global variable _qp for inheriting classes. More...

virtual bool	isIsotropic ()
	Is the implmented model isotropic? The safe default is 'false'. More...

virtual Real	computeTimeStepLimit ()

virtual TangentCalculationMethod	getTangentCalculationMethod ()


void	resetQpProperties () final
	Retained as empty methods to avoid a warning from Material.C in framework. These methods are unused in all inheriting classes and should not be overwritten. More...

void	resetProperties () final

Static Public Member Functions
static InputParameters	validParams ()

Protected Member Functions
virtual void	initQpStatefulProperties () override

Protected Attributes
const MaterialProperty< RankTwoTensor > &	_apparent_creep_strain
	Apparent creep strain (extracted from a LinearViscoelasticityBase object) More...

const MaterialProperty< RankFourTensor > &	_apparent_elasticity_tensor
	Apparent elasticity tensor (extracted from a LinearViscoelasticityBase object) More...

const MaterialProperty< RankFourTensor > &	_elasticity_tensor_inv
	Instantaneous compliance tensor (extracted from a LinearViscoelasticityBase object) More...

const std::string	_base_name
	Name used as a prefix for all material properties related to the stress update model. More...


MaterialProperty< RankTwoTensor > &	_creep_strain
	Creep strain. More...

const MaterialProperty< RankTwoTensor > &	_creep_strain_old

Detailed Description

This class computes a creep strain increment associated with a linear viscoelastic model contained in a LinearViscoelasticityBase material.

The creep strain increment is deduced from the elastic strain increment and added to the inelastic strain increment. The stress is reduced accordingly.

This material must be used in conjunction with ComputeMultipleInelasticStress, and uses an incremental (small or finite) strain formulation. To use viscoelastic models with total small strain, use a ComputeLinearViscoelasticStress material instead.

Definition at line 30 of file LinearViscoelasticStressUpdate.h.

Constructor & Destructor Documentation

◆ LinearViscoelasticStressUpdate()

LinearViscoelasticStressUpdate::LinearViscoelasticStressUpdate ( const InputParameters & parameters )

Definition at line 35 of file LinearViscoelasticStressUpdate.C.

   : StressUpdateBase(parameters),
     _creep_strain(declareProperty<RankTwoTensor>(_base_name + "creep_strain")),
     _creep_strain_old(getMaterialPropertyOld<RankTwoTensor>(_base_name + "creep_strain")),
     _apparent_creep_strain(getMaterialProperty<RankTwoTensor>("apparent_creep_strain")),
     _apparent_elasticity_tensor(getMaterialProperty<RankFourTensor>("apparent_elasticity_tensor")),
     _elasticity_tensor_inv(getMaterialProperty<RankFourTensor>("elasticity_tensor_inv"))
 {
 }

Member Function Documentation

◆ computeTimeStepLimit()

Real StressUpdateBase::computeTimeStepLimit ( )

virtualinherited

Reimplemented in RadialReturnStressUpdate.

Definition at line 56 of file StressUpdateBase.C.

 {
   return std::numeric_limits<Real>::max();
 }

◆ getTangentCalculationMethod()

virtual TangentCalculationMethod StressUpdateBase::getTangentCalculationMethod ( )

inlinevirtualinherited

Reimplemented in MultiParameterPlasticityStressUpdate, and RadialReturnCreepStressUpdateBase.

Definition at line 116 of file StressUpdateBase.h.

   {
     return TangentCalculationMethod::ELASTIC;
   }

Referenced by RadialReturnStressUpdate::updateState().

◆ initQpStatefulProperties()

void LinearViscoelasticStressUpdate::initQpStatefulProperties ( )

overrideprotectedvirtual

Definition at line 46 of file LinearViscoelasticStressUpdate.C.

 {
   _creep_strain[_qp].zero();
 }

◆ isIsotropic()

virtual bool StressUpdateBase::isIsotropic ( )

inlinevirtualinherited

Is the implmented model isotropic? The safe default is 'false'.

Reimplemented in RadialReturnStressUpdate, CappedDruckerPragerStressUpdate, and CappedMohrCoulombStressUpdate.

Definition at line 112 of file StressUpdateBase.h.

112 { return false; };

Referenced by ComputeMultipleInelasticStress::initialSetup().

◆ propagateQpStatefulProperties()

void LinearViscoelasticStressUpdate::propagateQpStatefulProperties ( )

overridevirtual

Reimplemented from StressUpdateBase.

Definition at line 52 of file LinearViscoelasticStressUpdate.C.

 {
   _creep_strain[_qp] = _creep_strain_old[_qp];
 }

◆ requiresIsotropicTensor()

virtual bool LinearViscoelasticStressUpdate::requiresIsotropicTensor ( )

inlineoverridevirtual

Does the model require the elasticity tensor to be isotropic?

Implements StressUpdateBase.

Definition at line 54 of file LinearViscoelasticStressUpdate.h.

54 { return false; }

◆ resetProperties()

void StressUpdateBase::resetProperties ( )

inlinefinalinherited

Definition at line 123 of file StressUpdateBase.h.

123 {}

◆ resetQpProperties()

void StressUpdateBase::resetQpProperties ( )

inlinefinalinherited

Retained as empty methods to avoid a warning from Material.C in framework. These methods are unused in all inheriting classes and should not be overwritten.

Definition at line 122 of file StressUpdateBase.h.

122 {}

◆ setQp()

void StressUpdateBase::setQp ( unsigned int qp )

inherited

Sets the value of the global variable _qp for inheriting classes.

Definition at line 43 of file StressUpdateBase.C.

 {
   _qp = qp;
 }

◆ updateState()

void LinearViscoelasticStressUpdate::updateState	(	RankTwoTensor &	strain_increment,
		RankTwoTensor &	inelastic_strain_increment,
		const RankTwoTensor &	rotation_increment,
		RankTwoTensor &	stress_new,
		const RankTwoTensor &	stress_old,
		const RankFourTensor &	elasticity_tensor,
		const RankTwoTensor &	elastic_strain_old,
		bool	compute_full_tangent_operator,
		RankFourTensor &	tangent_operator
	)

overridevirtual

Computes the new creep strain, and removes the creep contribution from the elastic strains and stress.

The tangent_operator is set equal to the elasticity tensor of the material.

Implements StressUpdateBase.

Definition at line 58 of file LinearViscoelasticStressUpdate.C.

 {
   RankTwoTensor current_mechanical_strain =
       elastic_strain_old + _creep_strain_old[_qp] + strain_increment;
  
   _creep_strain[_qp] =
       current_mechanical_strain - (_apparent_elasticity_tensor[_qp] * _elasticity_tensor_inv[_qp]) *
                                       (current_mechanical_strain - _apparent_creep_strain[_qp]);
  
   RankTwoTensor creep_strain_increment = _creep_strain[_qp] - _creep_strain_old[_qp];
  
   strain_increment -= creep_strain_increment;
   inelastic_strain_increment += creep_strain_increment;
   stress_new -= elasticity_tensor * creep_strain_increment;
 }

◆ validParams()

InputParameters LinearViscoelasticStressUpdate::validParams ( )

static

Definition at line 17 of file LinearViscoelasticStressUpdate.C.

 {
   InputParameters params = StressUpdateBase::validParams();
   params.addParam<std::string>(
       "apparent_creep_strain",
       "apparent_creep_strain",
       "name of the apparent creep strain (defined by a LinearViscoelasticityBase material)");
   params.addParam<std::string>(
       "apparent_elasticity_tensor",
       "apparent_elasticity_tensor",
       "name of the apparent elasticity tensor (defined by a LinearViscoelasticityBase material)");
   params.addParam<std::string>(
       "elasticity_tensor_inv",
       "elasticity_tensor_inv",
       "name of the real compliance tensor (defined by a LinearViscoelasticityBase material)");
   return params;
 }

Member Data Documentation

◆ _apparent_creep_strain

const MaterialProperty<RankTwoTensor>& LinearViscoelasticStressUpdate::_apparent_creep_strain

protected

Apparent creep strain (extracted from a LinearViscoelasticityBase object)

Definition at line 65 of file LinearViscoelasticStressUpdate.h.

Referenced by updateState().

◆ _apparent_elasticity_tensor

const MaterialProperty<RankFourTensor>& LinearViscoelasticStressUpdate::_apparent_elasticity_tensor

protected

Apparent elasticity tensor (extracted from a LinearViscoelasticityBase object)

Definition at line 67 of file LinearViscoelasticStressUpdate.h.

Referenced by updateState().

◆ _base_name

const std::string StressUpdateBase::_base_name

protectedinherited

Name used as a prefix for all material properties related to the stress update model.

Definition at line 128 of file StressUpdateBase.h.

◆ _creep_strain

MaterialProperty<RankTwoTensor>& LinearViscoelasticStressUpdate::_creep_strain

protected

Creep strain.

Definition at line 60 of file LinearViscoelasticStressUpdate.h.

Referenced by initQpStatefulProperties(), propagateQpStatefulProperties(), and updateState().

◆ _creep_strain_old

const MaterialProperty<RankTwoTensor>& LinearViscoelasticStressUpdate::_creep_strain_old

protected

Definition at line 61 of file LinearViscoelasticStressUpdate.h.

Referenced by propagateQpStatefulProperties(), and updateState().

◆ _elasticity_tensor_inv

const MaterialProperty<RankFourTensor>& LinearViscoelasticStressUpdate::_elasticity_tensor_inv

protected

Instantaneous compliance tensor (extracted from a LinearViscoelasticityBase object)

Definition at line 69 of file LinearViscoelasticStressUpdate.h.

Referenced by updateState().

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

tensor_mechanics/include/materials/LinearViscoelasticStressUpdate.h
tensor_mechanics/src/materials/LinearViscoelasticStressUpdate.C

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ LinearViscoelasticStressUpdate()

Member Function Documentation

◆ computeTimeStepLimit()

◆ getTangentCalculationMethod()

◆ initQpStatefulProperties()

◆ isIsotropic()

◆ propagateQpStatefulProperties()

◆ requiresIsotropicTensor()

◆ resetProperties()

◆ resetQpProperties()

◆ setQp()

◆ updateState()

◆ validParams()

Member Data Documentation

◆ _apparent_creep_strain

◆ _apparent_elasticity_tensor

◆ _base_name

◆ _creep_strain

◆ _creep_strain_old

◆ _elasticity_tensor_inv