#include <LinearElasticTruss.h>

Inheritance diagram for LinearElasticTruss:

Public Member Functions
	LinearElasticTruss (const InputParameters &parameters)

Static Public Member Functions
static InputParameters	validParams ()

Protected Member Functions
virtual void	computeQpStrain ()

virtual void	computeQpStress ()

virtual void	initQpStatefulProperties ()

virtual void	computeProperties ()

Protected Attributes
std::vector< MooseVariable * >	_disp_var

const std::string	_base_name

unsigned int	_ndisp

const VariableValue &	_youngs_modulus

MaterialProperty< Real > &	_total_stretch

MaterialProperty< Real > &	_elastic_stretch

MaterialProperty< Real > &	_axial_stress

MaterialProperty< Real > &	_e_over_l

Real	_origin_length

Real	_current_length

Private Attributes
const VariableValue &	_T

Real	_T0

Real	_thermal_expansion_coeff

Detailed Description

Definition at line 19 of file LinearElasticTruss.h.

Constructor & Destructor Documentation

◆ LinearElasticTruss()

LinearElasticTruss::LinearElasticTruss ( const InputParameters & parameters )

Definition at line 27 of file LinearElasticTruss.C.

   : TrussMaterial(parameters),
     _T(coupledValue("temperature")),
     _T0(getParam<Real>("temperature_ref")),
     _thermal_expansion_coeff(getParam<Real>("thermal_expansion_coeff"))
 {
 }

Member Function Documentation

◆ computeProperties()

void TrussMaterial::computeProperties ( )

protectedvirtualinherited

Definition at line 63 of file TrussMaterial.C.

 {
   // check for consistency of the number of element nodes
   mooseAssert(_current_elem->n_nodes() == 2, "Truss element needs to have exactly two nodes.");
  
   // fetch the two end nodes for _current_elem
   std::vector<const Node *> node;
   for (unsigned int i = 0; i < 2; ++i)
     node.push_back(_current_elem->node_ptr(i));
  
   // calculate original length of a truss element
   RealGradient dxyz;
   for (unsigned int i = 0; i < _ndisp; ++i)
     dxyz(i) = (*node[1])(i) - (*node[0])(i);
   _origin_length = dxyz.norm();
  
   // fetch the solution for the two end nodes
   NonlinearSystemBase & nonlinear_sys = _fe_problem.getNonlinearSystemBase();
   const NumericVector<Number> & sol = *nonlinear_sys.currentSolution();
  
   std::vector<Real> disp0, disp1;
   for (unsigned int i = 0; i < _ndisp; ++i)
   {
     disp0.push_back(sol(node[0]->dof_number(nonlinear_sys.number(), _disp_var[i]->number(), 0)));
     disp1.push_back(sol(node[1]->dof_number(nonlinear_sys.number(), _disp_var[i]->number(), 0)));
   }
  
   // calculate current length of a truss element
   for (unsigned int i = 0; i < _ndisp; ++i)
     dxyz(i) += disp1[i] - disp0[i];
   _current_length = dxyz.norm();
  
   for (_qp = 0; _qp < _qrule->n_points(); ++_qp)
   {
     _e_over_l[_qp] = _youngs_modulus[_qp] / _origin_length;
  
     computeQpStrain();
     computeQpStress();
   }
 }

◆ computeQpStrain()

void LinearElasticTruss::computeQpStrain ( )

protectedvirtual

Implements TrussMaterial.

Reimplemented in PlasticTruss.

Definition at line 36 of file LinearElasticTruss.C.

 {
   _total_stretch[_qp] = _current_length / _origin_length - 1.0;
   _elastic_stretch[_qp] = _total_stretch[_qp] - _thermal_expansion_coeff * (_T[_qp] - _T0);
 }

◆ computeQpStress()

void LinearElasticTruss::computeQpStress ( )

protectedvirtual

Implements TrussMaterial.

Reimplemented in PlasticTruss.

Definition at line 43 of file LinearElasticTruss.C.

 {
   _axial_stress[_qp] = _youngs_modulus[_qp] * _elastic_stretch[_qp];
 }

◆ initQpStatefulProperties()

void TrussMaterial::initQpStatefulProperties ( )

protectedvirtualinherited

Reimplemented in PlasticTruss.

Definition at line 55 of file TrussMaterial.C.

 {
   _axial_stress[_qp] = 0.0;
   _total_stretch[_qp] = 0.0;
   _elastic_stretch[_qp] = 0.0;
 }

Referenced by PlasticTruss::initQpStatefulProperties().

◆ validParams()

InputParameters LinearElasticTruss::validParams ( )

static

Definition at line 17 of file LinearElasticTruss.C.

 {
   InputParameters params = TrussMaterial::validParams();
   params.addClassDescription("Computes the linear elastic strain for a truss element");
   params.addParam<Real>("thermal_expansion_coeff", 0.0, "Thermal expansion coefficient in 1/K");
   params.addParam<Real>("temperature_ref", 273, "Reference temperature for thermal expansion in K");
   params.addCoupledVar("temperature", 273, "Temperature in Kelvin");
   return params;
 }