ComputeSmallStrainNOSPD Class Reference

Material class for bond-associated correspondence material model for small strain. More...

#include <ComputeSmallStrainNOSPD.h>

Inheritance diagram for ComputeSmallStrainNOSPD:

Public Member Functions
	ComputeSmallStrainNOSPD (const InputParameters &parameters)
virtual void	initQpStatefulProperties () override

Protected Member Functions
virtual void	computeQpStrain () override
	Function to compute strain tensors. More...
virtual void	computeQpTotalStrain ()
	Function to compute the total strain tensor for small strain case. More...
virtual void	computeProperties () override
virtual void	computeBondStretch () override
virtual void	computeQpDeformationGradient ()
	Function to compute bond-associated deformation gradient. More...

Protected Attributes
const bool	_plane_strain
	Plane strain problem or not, this is only used for mechanical stretch calculation. More...
const MaterialProperty< RankFourTensor > &	_Cijkl
	Material properties to fetch. More...
std::vector< MaterialPropertyName >	_eigenstrain_names
std::vector< const MaterialProperty< RankTwoTensor > * >	_eigenstrains
MaterialProperty< RankTwoTensor > &	_shape2
	Material properties to store. More...
MaterialProperty< RankTwoTensor > &	_deformation_gradient
MaterialProperty< RankTwoTensor > &	_ddgraddu
MaterialProperty< RankTwoTensor > &	_ddgraddv
MaterialProperty< RankTwoTensor > &	_ddgraddw
MaterialProperty< RankTwoTensor > &	_total_strain
MaterialProperty< RankTwoTensor > &	_mechanical_strain
MaterialProperty< Real > &	_multi

Detailed Description

Material class for bond-associated correspondence material model for small strain.

Definition at line 23 of file ComputeSmallStrainNOSPD.h.

Constructor & Destructor Documentation

ComputeSmallStrainNOSPD()

ComputeSmallStrainNOSPD::ComputeSmallStrainNOSPD

(

const InputParameters &

parameters

)

Definition at line 27 of file ComputeSmallStrainNOSPD.C.

  : ComputeStrainBaseNOSPD(parameters)
{
}

Member Function Documentation

computeBondStretch()

void ComputeStrainBaseNOSPD::computeBondStretch ( )

overrideprotectedvirtualinherited

Definition at line 156 of file ComputeStrainBaseNOSPD.C.

{
  _total_stretch[0] = _current_length / _origin_length - 1.0;
  _total_stretch[1] = _total_stretch[0];
  _mechanical_stretch[0] = _total_stretch[0];
 
  Real factor = 1.0;
  if (_plane_strain)
    factor = 1.0 + ElasticityTensorTools::getIsotropicPoissonsRatio(_Cijkl[0]);
 
  for (auto es : _eigenstrains)
    _mechanical_stretch[0] -= 0.5 * factor * ((*es)[0](2, 2) + (*es)[1](2, 2));
 
  _mechanical_stretch[1] = _mechanical_stretch[0];
}

Referenced by ComputeStrainBaseNOSPD::computeProperties().

computeProperties()

void ComputeStrainBaseNOSPD::computeProperties ( )

overrideprotectedvirtualinherited

Definition at line 145 of file ComputeStrainBaseNOSPD.C.

{
  setupMeshRelatedData();     // function from base class
  computeBondCurrentLength(); // current length of a bond from base class
  computeBondStretch();       // stretch of a bond
 
  for (_qp = 0; _qp < _nnodes; ++_qp)
    computeQpStrain();
}

computeQpDeformationGradient()

void ComputeStrainBaseNOSPD::computeQpDeformationGradient ( )

protectedvirtualinherited

Function to compute bond-associated deformation gradient.

Reimplemented in ComputeForceStabilizedSmallStrainNOSPD.

Definition at line 71 of file ComputeStrainBaseNOSPD.C.

{
  _shape2[_qp].zero();
  _deformation_gradient[_qp].zero();
  _ddgraddu[_qp].zero();
  _ddgraddv[_qp].zero();
  _ddgraddw[_qp].zero();
  _multi[_qp] = 0.0;
 
  // for cases when current bond was broken, assign shape tensor and deformation gradient to unity
  if (_bond_status_var->getElementalValue(_current_elem) < 0.5)
  {
    _shape2[_qp] = RankTwoTensor::initIdentity;
    _deformation_gradient[_qp] = _shape2[_qp];
  }
  else
  {
    if (_dim == 2)
      _shape2[_qp](2, 2) = _deformation_gradient[_qp](2, 2) = 1.0;
 
    const Node * cur_nd = _current_elem->node_ptr(_qp);
    const Node * end_nd = _current_elem->node_ptr(1 - _qp); // two nodes for edge2 element
    std::vector<dof_id_type> neighbors = _pdmesh.getNeighbors(cur_nd->id());
    std::vector<dof_id_type> bonds = _pdmesh.getBonds(cur_nd->id());
 
    unsigned int nb =
        std::find(neighbors.begin(), neighbors.end(), end_nd->id()) - neighbors.begin();
    std::vector<dof_id_type> dg_neighbors = _pdmesh.getDefGradNeighbors(cur_nd->id(), nb);
 
    // calculate the shape tensor and prepare the deformation gradient tensor
    Real dgnodes_vsum = 0.0;
    RealGradient ori_vec(_dim), cur_vec(_dim);
 
    for (unsigned int j = 0; j < dg_neighbors.size(); ++j)
      if (_bond_status_var->getElementalValue(_pdmesh.elemPtr(bonds[dg_neighbors[j]])) > 0.5)
      {
        Node * node_j = _pdmesh.nodePtr(neighbors[dg_neighbors[j]]);
        Real vol_j = _pdmesh.getPDNodeVolume(neighbors[dg_neighbors[j]]);
        dgnodes_vsum += vol_j;
        ori_vec = *node_j - *_pdmesh.nodePtr(cur_nd->id());
 
        for (unsigned int k = 0; k < _dim; ++k)
          cur_vec(k) = ori_vec(k) + _disp_var[k]->getNodalValue(*node_j) -
                       _disp_var[k]->getNodalValue(*cur_nd);
 
        Real ori_len = ori_vec.norm();
        for (unsigned int k = 0; k < _dim; ++k)
        {
          for (unsigned int l = 0; l < _dim; ++l)
          {
            _shape2[_qp](k, l) += _horiz_rad[_qp] / ori_len * ori_vec(k) * ori_vec(l) * vol_j;
            _deformation_gradient[_qp](k, l) +=
                _horiz_rad[_qp] / ori_len * cur_vec(k) * ori_vec(l) * vol_j;
          }
          // calculate derivatives of deformation_gradient w.r.t displacements of node i
          _ddgraddu[_qp](0, k) += -_horiz_rad[_qp] / ori_len * ori_vec(k) * vol_j;
          _ddgraddv[_qp](1, k) += -_horiz_rad[_qp] / ori_len * ori_vec(k) * vol_j;
          if (_dim == 3)
            _ddgraddw[_qp](2, k) += -_horiz_rad[_qp] / ori_len * ori_vec(k) * vol_j;
        }
      }
    // finalize the deformation gradient and its derivatives
    _deformation_gradient[_qp] *= _shape2[_qp].inverse();
    _ddgraddu[_qp] *= _shape2[_qp].inverse();
    _ddgraddv[_qp] *= _shape2[_qp].inverse();
    _ddgraddw[_qp] *= _shape2[_qp].inverse();
 
    // force state multiplier
    _multi[_qp] = _horiz_rad[_qp] / _origin_length * _node_vol[0] * _node_vol[1] * dgnodes_vsum /
                  _horiz_vol[_qp];
  }
}

Referenced by computeQpStrain(), and ComputeFiniteStrainNOSPD::computeQpStrain().

computeQpStrain()

void ComputeSmallStrainNOSPD::computeQpStrain ( )

overrideprotectedvirtual

Function to compute strain tensors.

Implements ComputeStrainBaseNOSPD.

Definition at line 33 of file ComputeSmallStrainNOSPD.C.

{
  computeQpDeformationGradient();
 
  computeQpTotalStrain();
 
  _mechanical_strain[_qp] = _total_strain[_qp];
 
  // Subtract Eigen strains
  for (auto es : _eigenstrains)
    _mechanical_strain[_qp] -= (*es)[_qp];
}

computeQpTotalStrain()

void ComputeSmallStrainNOSPD::computeQpTotalStrain ( )

protectedvirtual

Function to compute the total strain tensor for small strain case.

Reimplemented in ComputePlaneSmallStrainNOSPD.

Definition at line 47 of file ComputeSmallStrainNOSPD.C.

{
  // the small strain tensor
  _total_strain[_qp] = 0.5 * (_deformation_gradient[_qp].transpose() + _deformation_gradient[_qp]) -
                       RankTwoTensor(RankTwoTensor::initIdentity);
}

Referenced by computeQpStrain().

initQpStatefulProperties()

void ComputeStrainBaseNOSPD::initQpStatefulProperties ( )

overridevirtualinherited

Definition at line 57 of file ComputeStrainBaseNOSPD.C.

{
  _mechanical_strain[_qp].zero();
  _total_strain[_qp].zero();
  _deformation_gradient[_qp].zero();
  _deformation_gradient[_qp].addIa(1.0);
 
  if (_qrule->n_points() < 2) // Gauss_Lobatto: order = 2n-3 (n is number of qp)
    mooseError(
        "NOSPD models require Gauss_Lobatto rule and a minimum of 2 quadrature points, i.e., "
        "order of FIRST");
}

Member Data Documentation

_Cijkl

const MaterialProperty<RankFourTensor>& ComputeStrainBaseNOSPD::_Cijkl

protectedinherited

Material properties to fetch.

Definition at line 48 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeStrainBaseNOSPD::computeBondStretch().

_ddgraddu

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_ddgraddu

protectedinherited

Definition at line 57 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeForceStabilizedSmallStrainNOSPD::computeQpDeformationGradient(), and ComputeStrainBaseNOSPD::computeQpDeformationGradient().

_ddgraddv

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_ddgraddv

protectedinherited

Definition at line 58 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeForceStabilizedSmallStrainNOSPD::computeQpDeformationGradient(), and ComputeStrainBaseNOSPD::computeQpDeformationGradient().

_ddgraddw

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_ddgraddw

protectedinherited

Definition at line 59 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeForceStabilizedSmallStrainNOSPD::computeQpDeformationGradient(), and ComputeStrainBaseNOSPD::computeQpDeformationGradient().

_deformation_gradient

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_deformation_gradient

protectedinherited

Definition at line 55 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeForceStabilizedSmallStrainNOSPD::computeQpDeformationGradient(), ComputeStrainBaseNOSPD::computeQpDeformationGradient(), ComputePlaneFiniteStrainNOSPD::computeQpFhat(), ComputeFiniteStrainNOSPD::computeQpFhat(), ComputePlaneSmallStrainNOSPD::computeQpTotalStrain(), computeQpTotalStrain(), and ComputeStrainBaseNOSPD::initQpStatefulProperties().

_eigenstrain_names

std::vector<MaterialPropertyName> ComputeStrainBaseNOSPD::_eigenstrain_names

protectedinherited

Definition at line 49 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeFiniteStrainNOSPD::ComputeFiniteStrainNOSPD(), and ComputeStrainBaseNOSPD::ComputeStrainBaseNOSPD().

_eigenstrains

std::vector<const MaterialProperty<RankTwoTensor> *> ComputeStrainBaseNOSPD::_eigenstrains

protectedinherited

Definition at line 50 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeStrainBaseNOSPD::computeBondStretch(), computeQpStrain(), ComputeStrainBaseNOSPD::ComputeStrainBaseNOSPD(), and ComputeFiniteStrainNOSPD::subtractEigenstrainIncrementFromStrain().

_mechanical_strain

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_mechanical_strain

protectedinherited

Definition at line 62 of file ComputeStrainBaseNOSPD.h.

Referenced by computeQpStrain(), ComputeFiniteStrainNOSPD::computeQpStrain(), and ComputeStrainBaseNOSPD::initQpStatefulProperties().

_multi

MaterialProperty<Real>& ComputeStrainBaseNOSPD::_multi

protectedinherited

Definition at line 64 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeForceStabilizedSmallStrainNOSPD::computeQpDeformationGradient(), and ComputeStrainBaseNOSPD::computeQpDeformationGradient().

_plane_strain

const bool ComputeStrainBaseNOSPD::_plane_strain

protectedinherited

Plane strain problem or not, this is only used for mechanical stretch calculation.

Definition at line 45 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeStrainBaseNOSPD::computeBondStretch().

_shape2

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_shape2

protectedinherited

Material properties to store.

Definition at line 54 of file ComputeStrainBaseNOSPD.h.

Referenced by ComputeForceStabilizedSmallStrainNOSPD::computeQpDeformationGradient(), and ComputeStrainBaseNOSPD::computeQpDeformationGradient().

_total_strain

MaterialProperty<RankTwoTensor>& ComputeStrainBaseNOSPD::_total_strain

protectedinherited

Definition at line 61 of file ComputeStrainBaseNOSPD.h.

Referenced by computeQpStrain(), ComputeFiniteStrainNOSPD::computeQpStrain(), ComputePlaneSmallStrainNOSPD::computeQpTotalStrain(), computeQpTotalStrain(), and ComputeStrainBaseNOSPD::initQpStatefulProperties().

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

• peridynamics/include/materials/ComputeSmallStrainNOSPD.h
• peridynamics/src/materials/ComputeSmallStrainNOSPD.C