Line data    Source code

       1             : //* This file is part of the MOOSE framework
       2             : //* https://mooseframework.inl.gov
       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             : #pragma once
      11             : 
      12             : #include "StressUpdateBase.h"
      13             : #include "LinearViscoelasticityBase.h"
      14             : 
      15             : /**
      16             :  * This class computes a creep strain increment associated with a linear viscoelastic
      17             :  * model contained in a LinearViscoelasticityBase material. The creep strain increment
      18             :  * is deduced from the elastic strain increment and added to the inelastic strain increment.
      19             :  * The stress is reduced accordingly.
      20             :  *
      21             :  * This material must be used in conjunction with ComputeMultipleInelasticStress, and uses
      22             :  * an incremental (small or finite) strain formulation. To use viscoelastic models with
      23             :  * total small strain, use a ComputeLinearViscoelasticStress material instead.
      24             :  */
      25             : class LinearViscoelasticStressUpdate : public StressUpdateBase
      26             : {
      27             : public:
      28             :   static InputParameters validParams();
      29             : 
      30             :   LinearViscoelasticStressUpdate(const InputParameters & parameters);
      31             : 
      32             :   /**
      33             :    * Computes the new creep strain, and removes the creep contribution from the elastic strains and
      34             :    * stress. The tangent_operator is set equal to the elasticity tensor of the material.
      35             :    */
      36             :   using StressUpdateBase::updateState;
      37             : 
      38             :   virtual void updateState(RankTwoTensor & strain_increment,
      39             :                            RankTwoTensor & inelastic_strain_increment,
      40             :                            const RankTwoTensor & rotation_increment,
      41             :                            RankTwoTensor & stress_new,
      42             :                            const RankTwoTensor & stress_old,
      43             :                            const RankFourTensor & elasticity_tensor,
      44             :                            const RankTwoTensor & elastic_strain_old,
      45             :                            bool compute_full_tangent_operator,
      46             :                            RankFourTensor & tangent_operator) override;
      47             : 
      48             :   /// Reimplemented from StressUpdateBase
      49             :   virtual void propagateQpStatefulProperties() override;
      50             : 
      51         126 :   virtual bool requiresIsotropicTensor() override { return false; }
      52             : 
      53             : protected:
      54             :   virtual void initQpStatefulProperties() override;
      55             : 
      56             :   ///@{ Creep strain
      57             :   MaterialProperty<RankTwoTensor> & _creep_strain;
      58             :   const MaterialProperty<RankTwoTensor> & _creep_strain_old;
      59             :   ///@}
      60             : 
      61             :   /// Apparent creep strain (extracted from a LinearViscoelasticityBase object)
      62             :   const MaterialProperty<RankTwoTensor> & _apparent_creep_strain;
      63             :   /// Apparent elasticity tensor (extracted from a LinearViscoelasticityBase object)
      64             :   const MaterialProperty<RankFourTensor> & _apparent_elasticity_tensor;
      65             :   /// Instantaneous compliance tensor (extracted from a LinearViscoelasticityBase object)
      66             :   const MaterialProperty<RankFourTensor> & _elasticity_tensor_inv;
      67             : };