Line data    Source code

       1             : //* This file is part of the MOOSE framework
       2             : //* https://www.mooseframework.org
       3             : //*
       4             : //* All rights reserved, see COPYRIGHT for full restrictions
       5             : //* https://github.com/idaholab/moose/blob/master/COPYRIGHT
       6             : //*
       7             : //* Licensed under LGPL 2.1, please see LICENSE for details
       8             : //* https://www.gnu.org/licenses/lgpl-2.1.html
       9             : 
      10             : #include "ComputeIncrementalSmallStrain.h"
      11             : #include "Assembly.h"
      12             : #include "libmesh/quadrature.h"
      13             : 
      14             : registerMooseObject("TensorMechanicsApp", ComputeIncrementalSmallStrain);
      15             : 
      16             : InputParameters
      17        2952 : ComputeIncrementalSmallStrain::validParams()
      18             : {
      19        2952 :   InputParameters params = ComputeIncrementalStrainBase::validParams();
      20        2952 :   params.addClassDescription(
      21             :       "Compute a strain increment and rotation increment for small strains.");
      22        2952 :   return params;
      23           0 : }
      24             : 
      25        2214 : ComputeIncrementalSmallStrain::ComputeIncrementalSmallStrain(const InputParameters & parameters)
      26        2214 :   : ComputeIncrementalStrainBase(parameters)
      27             : {
      28        2214 : }
      29             : 
      30             : void
      31      560694 : ComputeIncrementalSmallStrain::computeProperties()
      32             : {
      33             :   Real volumetric_strain = 0.0;
      34     3598584 :   for (_qp = 0; _qp < _qrule->n_points(); ++_qp)
      35             :   {
      36     3037890 :     RankTwoTensor total_strain_increment;
      37     3037890 :     computeTotalStrainIncrement(total_strain_increment);
      38             : 
      39     3037890 :     _strain_increment[_qp] = total_strain_increment;
      40             : 
      41     3037890 :     if (_volumetric_locking_correction)
      42      216968 :       volumetric_strain += total_strain_increment.trace() * _JxW[_qp] * _coord[_qp];
      43             :   }
      44      560694 :   if (_volumetric_locking_correction)
      45       54092 :     volumetric_strain /= _current_elem_volume;
      46             : 
      47     3598584 :   for (_qp = 0; _qp < _qrule->n_points(); ++_qp)
      48             :   {
      49     3037890 :     Real trace = _strain_increment[_qp].trace();
      50     3037890 :     if (_volumetric_locking_correction)
      51             :     {
      52      216968 :       _strain_increment[_qp](0, 0) += (volumetric_strain - trace) / 3.0;
      53      216968 :       _strain_increment[_qp](1, 1) += (volumetric_strain - trace) / 3.0;
      54      216968 :       _strain_increment[_qp](2, 2) += (volumetric_strain - trace) / 3.0;
      55             :     }
      56             : 
      57     3037890 :     _total_strain[_qp] = _total_strain_old[_qp] + _strain_increment[_qp];
      58             : 
      59             :     // Remove the Eigen strain increment
      60     3037890 :     subtractEigenstrainIncrementFromStrain(_strain_increment[_qp]);
      61             : 
      62             :     // strain rate
      63     3037890 :     if (_dt > 0)
      64     3028270 :       _strain_rate[_qp] = _strain_increment[_qp] / _dt;
      65             :     else
      66        9620 :       _strain_rate[_qp].zero();
      67             : 
      68             :     // Update strain in intermediate configuration: rotations are not needed
      69     3037890 :     _mechanical_strain[_qp] = _mechanical_strain_old[_qp] + _strain_increment[_qp];
      70             : 
      71             :     // incremental small strain does not include rotation
      72     3037890 :     _rotation_increment[_qp].setToIdentity();
      73             :   }
      74      560694 : }
      75             : 
      76             : void
      77     2918786 : ComputeIncrementalSmallStrain::computeTotalStrainIncrement(RankTwoTensor & total_strain_increment)
      78             : {
      79             :   // Deformation gradient
      80             :   auto A = RankTwoTensor::initializeFromRows(
      81     2918786 :       (*_grad_disp[0])[_qp], (*_grad_disp[1])[_qp], (*_grad_disp[2])[_qp]);
      82             : 
      83             :   // Old Deformation gradient
      84             :   auto Fbar = RankTwoTensor ::initializeFromRows(
      85     2918786 :       (*_grad_disp_old[0])[_qp], (*_grad_disp_old[1])[_qp], (*_grad_disp_old[2])[_qp]);
      86             : 
      87     2918786 :   _deformation_gradient[_qp] = A;
      88     2918786 :   _deformation_gradient[_qp].addIa(1.0);
      89             : 
      90     2918786 :   A -= Fbar; // A = grad_disp - grad_disp_old
      91             : 
      92     2918786 :   total_strain_increment = 0.5 * (A + A.transpose());
      93     2918786 : }