Description

Material for a single layer of a thin shell (Kirchoff-Love shell theory, i.e.

shells without shear effects). This base implementation assumes that one creates a ChMaterialShellKirchhoff by providing three components:

an elasticity model (from ChElasticityKirchhoff classes)
a plasticity model (optional, from ChPlasticityKirchhoff classes)
a damping model (optional, from ChDampingKirchhoff classes)

Thickness is defined when adding a ChMaterialShellKirchhoff material as a layer in a shell finite element. A material can be shared between multiple layers.

#include <ChMaterialShellKirchhoff.h>

Public Member Functions
	ChMaterialShellKirchhoff (std::shared_ptr< ChElasticityKirchhoff > melasticity)

	ChMaterialShellKirchhoff (std::shared_ptr< ChElasticityKirchhoff > melasticity, std::shared_ptr< ChPlasticityKirchhoff > mplasticity)

	ChMaterialShellKirchhoff (std::shared_ptr< ChElasticityKirchhoff > melasticity, std::shared_ptr< ChPlasticityKirchhoff > mplasticity, std::shared_ptr< ChDampingKirchhoff > mdamping)

virtual void	ComputeStress (ChVector<> &n, ChVector<> &m, const ChVector<> &eps, const ChVector<> &kur, const double z_inf, const double z_sup, const double angle, ChShellKirchhoffInternalData mdata_new=nullptr, const ChShellKirchhoffInternalData mdata=nullptr)
	Compute the generalized cut force and cut torque, given the actual generalized section strain expressed as deformation vector e and curvature k, that is: {n,m}=f({e,k}), and given the actual material state required for plasticity if any (but if mdata=nullptr, computes only the elastic force). More...

virtual void	ComputeStiffnessMatrix (ChMatrixRef K, const ChVector<> &eps, const ChVector<> &kur, const double z_inf, const double z_sup, const double angle, const ChShellKirchhoffInternalData *mdata=nullptr)
	Compute the 6x6 tangent material stiffness matrix [Km] = dσ/dε at a given strain state, and at given internal data state (if mdata=nullptr, computes only the elastic tangent stiffenss, regardless of plasticity). More...

void	SetElasticity (std::shared_ptr< ChElasticityKirchhoff > melasticity)
	Set the elasticity model for this section. More...

std::shared_ptr< ChElasticityKirchhoff >	GetElasticity ()
	Get the elasticity model for this section. More...

void	SetPlasticity (std::shared_ptr< ChPlasticityKirchhoff > mplasticity)
	Set the plasticity model for this section. More...

std::shared_ptr< ChPlasticityKirchhoff >	GetPlasticity ()
	Get the elasticity model for this section, if any. More...

void	SetDamping (std::shared_ptr< ChDampingKirchhoff > mdamping)
	Set the damping model for this section. More...

std::shared_ptr< ChDampingKirchhoff >	GetDamping ()
	Get the damping model for this section. More...

void	SetDensity (double md)
	Set the density of the shell (kg/m^3)

double	GetDensity () const

Constructor & Destructor Documentation

◆ ChMaterialShellKirchhoff() [1/3]

chrono::fea::ChMaterialShellKirchhoff::ChMaterialShellKirchhoff ( std::shared_ptr< ChElasticityKirchhoff > melasticity )

Parameters

melasticity elasticity model

◆ ChMaterialShellKirchhoff() [2/3]

chrono::fea::ChMaterialShellKirchhoff::ChMaterialShellKirchhoff	(	std::shared_ptr< ChElasticityKirchhoff >	melasticity,
		std::shared_ptr< ChPlasticityKirchhoff >	mplasticity
	)

Parameters

melasticity	elasticity model
mplasticity	plasticity model, if any

◆ ChMaterialShellKirchhoff() [3/3]

chrono::fea::ChMaterialShellKirchhoff::ChMaterialShellKirchhoff	(	std::shared_ptr< ChElasticityKirchhoff >	melasticity,
		std::shared_ptr< ChPlasticityKirchhoff >	mplasticity,
		std::shared_ptr< ChDampingKirchhoff >	mdamping
	)

Parameters

melasticity	elasticity model
mplasticity	plasticity model, if any
mdamping	damping model, if any

Member Function Documentation

◆ ComputeStiffnessMatrix()

void chrono::fea::ChMaterialShellKirchhoff::ComputeStiffnessMatrix	(	ChMatrixRef	K,
		const ChVector<> &	eps,
		const ChVector<> &	kur,
		const double	z_inf,
		const double	z_sup,
		const double	angle,
		const ChShellKirchhoffInternalData *	mdata = `nullptr`
	)

virtual

Compute the 6x6 tangent material stiffness matrix [Km] = dσ/dε at a given strain state, and at given internal data state (if mdata=nullptr, computes only the elastic tangent stiffenss, regardless of plasticity).

Parameters

K	12x12 stiffness matrix
eps	strains e_11, e_22, e_12
kur	curvature k_11, k_22, k_12
z_inf	layer lower z value (along thickness coord)
z_sup	layer upper z value (along thickness coord)
angle	layer angle respect to x (if needed)
mdata	material internal variables, at this point, if any, including {p_strain_e, p_strain_k, p_strain_acc}

◆ ComputeStress()

void chrono::fea::ChMaterialShellKirchhoff::ComputeStress	(	ChVector<> &	n,
		ChVector<> &	m,
		const ChVector<> &	eps,
		const ChVector<> &	kur,
		const double	z_inf,
		const double	z_sup,
		const double	angle,
		ChShellKirchhoffInternalData *	mdata_new = `nullptr`,
		const ChShellKirchhoffInternalData *	mdata = `nullptr`
	)

virtual

Compute the generalized cut force and cut torque, given the actual generalized section strain expressed as deformation vector e and curvature k, that is: {n,m}=f({e,k}), and given the actual material state required for plasticity if any (but if mdata=nullptr, computes only the elastic force).

If there is plasticity, the stress is clamped by automatically performing an implicit return mapping. In sake of generality, if possible this is the function that should be used by beam finite elements to compute internal forces, ex.by some Gauss quadrature.

Parameters

n	forces n_11, n_22, n_12 (per unit length)
m	torques m_11, m_22, m_12 (per unit length)
eps	strains e_11, e_22, e_12
kur	curvature k_11, k_22, k_12
z_inf	layer lower z value (along thickness coord)
z_sup	layer upper z value (along thickness coord)
angle	layer angle respect to x (if needed)
mdata_new	updated material internal variables, at this point, including {p_strain_e, p_strain_k, p_strain_acc}
mdata	current material internal variables, at this point, including {p_strain_e, p_strain_k, p_strain_acc}

◆ GetDamping()

std::shared_ptr<ChDampingKirchhoff> chrono::fea::ChMaterialShellKirchhoff::GetDamping ( )

inline

Get the damping model for this section.

By default no damping.

◆ GetElasticity()

std::shared_ptr<ChElasticityKirchhoff> chrono::fea::ChMaterialShellKirchhoff::GetElasticity ( )

inline

Get the elasticity model for this section.

Use this function to access parameters such as stiffness, Young modulus, etc. By default it uses a simple centered linear elastic model.

◆ GetPlasticity()

std::shared_ptr<ChPlasticityKirchhoff> chrono::fea::ChMaterialShellKirchhoff::GetPlasticity ( )

inline

Get the elasticity model for this section, if any.

Use this function to access parameters such as yeld limit, etc.

◆ SetDamping()

void chrono::fea::ChMaterialShellKirchhoff::SetDamping ( std::shared_ptr< ChDampingKirchhoff > mdamping )

Set the damping model for this section.

By default no damping.

◆ SetElasticity()

void chrono::fea::ChMaterialShellKirchhoff::SetElasticity ( std::shared_ptr< ChElasticityKirchhoff > melasticity )

Set the elasticity model for this section.

By default it uses a simple centered linear elastic model, but you can set more complex models.

◆ SetPlasticity()

void chrono::fea::ChMaterialShellKirchhoff::SetPlasticity ( std::shared_ptr< ChPlasticityKirchhoff > mplasticity )

Set the plasticity model for this section.

This is independent from the elasticity model. Note that by default there is no plasticity model, so by default plasticity never happens.

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

/builds/uwsbel/chrono/src/chrono/fea/ChMaterialShellKirchhoff.h
/builds/uwsbel/chrono/src/chrono/fea/ChMaterialShellKirchhoff.cpp

Description

Public Member Functions

Constructor & Destructor Documentation

◆ ChMaterialShellKirchhoff() [1/3]

◆ ChMaterialShellKirchhoff() [2/3]

◆ ChMaterialShellKirchhoff() [3/3]

Member Function Documentation

◆ ComputeStiffnessMatrix()

◆ ComputeStress()

◆ GetDamping()

◆ GetElasticity()

◆ GetPlasticity()

◆ SetDamping()

◆ SetElasticity()

◆ SetPlasticity()