a property for computing stress associated to DEM::Element More...

#include <Stress.hpp>

Inheritance diagram for GranOO3::DEM::Stress:

[legend]

Public Member Functions
	Stress ()
	constructor More...

virtual	~Stress ()
	destructor More...

virtual std::string	info () const
	Display some useful info in the terminal More...

double	get_hydrostatic_stress () const
	get the hydrostatic stress More...

double	get_vonmises_stress () const
	get the von Mises stress More...

double	get_tresca_stress () const
	get the Tresca stress More...

void	add_criterion (double value)
	add a criterion, the criterion is often used for fracture but you can use it as you want More...

double &	criterion (size_t i)
	get the i_th criterion More...

void	compute_virial_stress ()
	compute the stress using the virial method More...

void	compute_virial_stress_for (Element de, unsigned int level, std::set< Element > &set)
	a util recursive method for computing virial stress More...

void	compute_lsq_stress ()
	compute the stress using a least square method (EXPERIMENTAL) More...

void	update_principal_stress ()
	update the principal stresses from the current value of the _stress_tensor attribute More...

Public Member Functions inherited from GranOO3::Core::Prop< Element >
	Prop ()

virtual	~Prop ()

Element &	item ()

const Element &	item () const

void	set_item (Element &)

virtual void	set_color (const Core::Color &)

Core::Color &	get_color ()

float &	get_line_width ()

virtual void	add (SetOf< Prop< Element > > *)

virtual void	erase (SetOf< Prop< Element > > *)

virtual std::ostream &	write_ascii (std::ostream &out) const

virtual std::istream &	read_ascii (std::istream &in)

Public Member Functions inherited from GranOO3::Core::Base
virtual	~Base ()

size_t	numID () const

size_t	uID () const

void	set_numID (size_t val)

void	clear_numID ()

Physic::Material &	get_mat () const

void	set_mat (Physic::Material *)

Base &	item ()

const Base &	item () const

bool	is_same (const Base &) const

template<class T >
T &	cast_to ()

template<class T >
const T &	cast_to () const

template<class T >
bool	is () const

virtual bool	is (size_t) const

virtual const std::string &	get_ID () const

virtual Base &	clone ()

template<class T >
T &	clone_to ()

virtual std::ostream &	export_to_povray (std::ostream &out) const

Signal< Base & > &	deleted_signal ()

Public Member Functions inherited from GranOO3::Core::Null
	Null ()

virtual	~Null ()

Public Member Functions inherited from GranOO3::Core::Drawable
	Drawable ()

virtual	~Drawable ()

virtual void	draw ()

virtual void	draw_edge ()

virtual void	init_default_color ()

virtual std::ostream &	get_info (std::ostream &os) const

virtual const Color &	default_color () const

Color &	get_color ()

const Color &	get_color () const

virtual void	set_alpha (float alpha)

void	apply_color () const

void	apply_edge_color () const

void	apply_default_color ()

void	apply_selected_color ()

void	set_line_width (float)

float	get_line_width () const

float &	get_line_width ()

void	apply_line_width () const

bool	is_visible () const

void	set_visible (bool)

void	paint ()

void	paint_edge ()

unsigned int	get_item_glkey () const

Public Member Functions inherited from GranOO3::Core::Register< Base >
	Register ()

virtual	~Register ()

void	erase_from_all_setof ()

bool	belong_to_setof (const std::string &setOfId) const

bool	belong_to_setof (const SetOf< Base > &set) const

std::list< SetOf< Base > * > &	get_setof_list ()

unsigned long long int	get_numeric_ID () const

Public Member Functions inherited from GranOO3::Core::Register< type >
	Register ()

virtual	~Register ()

void	erase_from_all_setof ()

bool	belong_to_setof (const std::string &setOfId) const

bool	belong_to_setof (const SetOf< type > &set) const

std::list< SetOf< type > * > &	get_setof_list ()

unsigned long long int	get_numeric_ID () const

Public Member Functions inherited from GranOO3::Core::Register< Stress >
	Register ()

virtual	~Register ()

void	erase_from_all_setof ()

bool	belong_to_setof (const std::string &setOfId) const

bool	belong_to_setof (const SetOf< Stress > &set) const

std::list< SetOf< Stress > * > &	get_setof_list ()

unsigned long long int	get_numeric_ID () const

Private Member Functions
template<class Archive >
void	serialize (Archive &ar, const unsigned int)
	complete serializing of the item in the *.gdd format More...

Private Attributes
Geom::SymTensor	_stress_tensor
	the main stress tensor which is updated by the compute_virial_stress() and the compute_lsq_stress() methods. More...

Geom::Point	_principal_point
	this is just a trick for having a local frame ("useless as this") More...

Geom::Quaternion	_principal_quat
	this quaternion that model the rotation matrix (from global frame) for retrieving the principal directions More...

Geom::Frame	_principal_frame
	the local frame which are expressed the principal stresses (principal direction) More...

Geom::Vector	_principal_stress
	a vector that stores the three principal stresses, note that the component are ordered like this X > Y > Z More...

double	_principal_stress_1
	the value of the first (maximal) principal stress More...

double	_principal_stress_2
	the value of the second (intermediate) principal stress More...

double	_principal_stress_3
	the value of the third (lower) principal stress More...

double	_criterion
	the value of the main criterion (in case of only one criterion is applied) More...

std::vector< double >	_criterion_list
	the values of criteria (in case of many criteria are applied) More...

unsigned int	_neighbour_level
	the neighbor level (level of neighboring) for the computation of the virial stress. More...

double	_volume_fraction
	the volume fraction for computing virial stress (virial stress computation needs the real volume). More...

bool	_include_velocity
	a flag for including the velocity within the virial stress computation More...

bool	_periodic
	a flag for including priodic condition for the virial stress computation More...

Friends
class	boost::serialization::access

Additional Inherited Members
Public Types inherited from GranOO3::Core::Prop< Element >
typedef Element	Owner

Static Public Member Functions inherited from GranOO3::Core::Base
static Base &	get_by_numID (size_t)

static void	clear_all_numID ()

static unsigned int	get_sub_class_number ()

Static Public Member Functions inherited from GranOO3::Core::Drawable
static Drawable &	get_drawable_item_by_glkey (int)

static void	set_draw_precision (unsigned int p)

static void	increase_draw_precision ()

static void	decrease_draw_precision ()

static unsigned int	get_draw_precision ()

Static Public Attributes inherited from GranOO3::Core::Null
static Null	null = Null()

Protected Member Functions inherited from GranOO3::Core::Prop< Element >
virtual Base &	base_item ()

virtual const Base &	base_item () const

void	serialize (Archive &ar, const unsigned int)

Protected Member Functions inherited from GranOO3::Core::Base
	Base ()

Static Protected Member Functions inherited from GranOO3::Core::Base
static unsigned int	affect_class_rank_ID ()

Detailed Description

a property for computing stress associated to DEM::Element

The aim of this DEM::Element property is to compute stresses associated to DEM::Element. Here, the method used for computing strains can be chosen between two methods :

virial stress method (see [1])
least square (but it is quite experimental) The stress property is often used for computing crack in a continuum using the plugin APPLY-FRACTURE.

[1] André, D., Jebahi, M., Iordanoff, I., Charles, J. L., & Néauport, J. (2013). Using the discrete element method to simulate brittle fracture in the indentation of a silica glass with a blunt indenter. Computer Methods in Applied Mechanics and Engineering, 265, 136-147.

Constructor & Destructor Documentation

◆ Stress()

GranOO3::DEM::Stress::Stress ( )

constructor

Construct a new Stress element. Do not call this constructor. To build a new Stress instance, you must create a new property by invoking the Element::new_prop<Stress>() method of the Element class.

◆ ~Stress()

GranOO3::DEM::Stress::~Stress ( )

virtual

destructor

Destruct a Stress instance. Be aware, as Stress is a property, you must not invoke destructor by yourself, it could lead to unexpected behavior. Note that the Stress instances are automatically destructed when their associated elements are destructed.

Member Function Documentation

◆ add_criterion()

void GranOO3::DEM::Stress::add_criterion ( double value )

add a criterion, the criterion is often used for fracture but you can use it as you want

Parameters

[in] value : the treshold value of the criterion

This method can be used to store one or more criteria within a DEM::Element. It can be used for applying different criteria with different discrete elements and/or applying more that one criteria to a given discrete element.

◆ compute_lsq_stress()

void GranOO3::DEM::Stress::compute_lsq_stress ( )

compute the stress using a least square method (EXPERIMENTAL)

The idea here is too use the same method as DEM::Strain for computing stresses by taking into account all the interaction forces and torques of neighbors element. However, it does not work as expected :-( TODO: debug this or remove this

This method update the _stress_tensor attribute using a least square method. The idea here is too use the same method as DEM::Strain for computing stresses by taking into account all the interaction forces and torques of neighbors element. However, it does not work as expected :-( TODO: debug this or remove this

◆ compute_virial_stress()

void GranOO3::DEM::Stress::compute_virial_stress ( )

compute the stress using the virial method

This method update the _stress_tensor attribute using the virial stress method [1].

Nguyen, T. T., André, D., & Huger, M. (2019). Analytic laws for direct calibration of discrete element modeling of brittle elastic media using cohesive beam model. Computational Particle Mechanics, 6(3), 393-409.

◆ compute_virial_stress_for()

void GranOO3::DEM::Stress::compute_virial_stress_for	(	Element *	de,
		unsigned int	level,
		std::set< Element * > &	set
	)

a util recursive method for computing virial stress

Parameters

[in]	de	: a pointer to the current element for computing virial stress
[in]	level	: the current neighbor level
[in]	set	: that list of element that has been parsed

This method is called by the compute_virial_stress() method. There is probably no reason for you to call directly this method. If you want to learn more about the neighbor level, please refer to [1].

Nguyen, T. T., André, D., & Huger, M. (2019). Analytic laws for direct calibration of discrete element modeling of brittle elastic media using cohesive beam model. Computational Particle Mechanics, 6(3), 393-409.

◆ criterion()

double & GranOO3::DEM::Stress::criterion ( size_t i )

get the i_th criterion

Parameters

[in] i : the rank of the criterion to get

Returns: a (modifiable) reference to the criterion value

This method can be used to retrieve the criterion value with its associated rank i.

◆ get_hydrostatic_stress()

double GranOO3::DEM::Stress::get_hydrostatic_stress ( ) const

get the hydrostatic stress

Returns: the hydrostatic stress value

Note that the hydrostatic is computed on the fly with the current vales of the _stress_tensor attribute.

◆ get_tresca_stress()

double GranOO3::DEM::Stress::get_tresca_stress ( ) const

get the Tresca stress

Returns: the Tresca stress value

Note that the Tresca is computed on the fly with the current vales of the _principal_stress_1 and the _principal_stress_3 attributes.

◆ get_vonmises_stress()

double GranOO3::DEM::Stress::get_vonmises_stress ( ) const

get the von Mises stress

Returns: the von Mises stress value

Note that the von Mises is computed on the fly with the current vales of the _stress_tensor attribute.

◆ info()

std::string GranOO3::DEM::Stress::info ( ) const

virtual

Display some useful info in the terminal

Reimplemented from GranOO3::Core::Prop< Element >.

◆ serialize()

template<class Archive >

void GranOO3::DEM::Stress::serialize	(	Archive &	ar,
		const unsigned int	version
	)

private

complete serializing of the item in the *.gdd format

See also: the Domain classes to get additional info about I/O

◆ update_principal_stress()

void GranOO3::DEM::Stress::update_principal_stress ( )

update the principal stresses from the current value of the _stress_tensor attribute

This method computes the principal stresses and stores the results in the _principal_stress,
_principal_stress_1, _principal_stress_2, _principal_stress_3 attributes

Friends And Related Function Documentation

◆ boost::serialization::access

friend class boost::serialization::access

friend

Member Data Documentation

◆ _criterion

double GranOO3::DEM::Stress::_criterion

private

the value of the main criterion (in case of only one criterion is applied)

◆ _criterion_list

std::vector< double > GranOO3::DEM::Stress::_criterion_list

private

the values of criteria (in case of many criteria are applied)

◆ _include_velocity

bool GranOO3::DEM::Stress::_include_velocity

private

a flag for including the velocity within the virial stress computation

Based on our experiences, including velocity is useless but we let this option valid... just in case

◆ _neighbour_level

unsigned int GranOO3::DEM::Stress::_neighbour_level

private

the neighbor level (level of neighboring) for the computation of the virial stress.

0 corresponds to the direct neighbors, 1 corresponds to the second level of neighbors and so on...

◆ _periodic

bool GranOO3::DEM::Stress::_periodic

private

a flag for including priodic condition for the virial stress computation

For neighbour level = 1, this flag must be activated when dealing with periodic condition because an element can interact with an other element situated at the other side of the domain. You can let this flag to false in other case.

◆ _principal_frame

Geom::Frame GranOO3::DEM::Stress::_principal_frame

private

the local frame which are expressed the principal stresses (principal direction)

◆ _principal_point

Geom::Point GranOO3::DEM::Stress::_principal_point

private

this is just a trick for having a local frame ("useless as this")

◆ _principal_quat

Geom::Quaternion GranOO3::DEM::Stress::_principal_quat

private

this quaternion that model the rotation matrix (from global frame) for retrieving the principal directions

◆ _principal_stress

Geom::Vector GranOO3::DEM::Stress::_principal_stress

private

a vector that stores the three principal stresses, note that the component are ordered like this X > Y > Z

◆ _principal_stress_1

double GranOO3::DEM::Stress::_principal_stress_1

private

the value of the first (maximal) principal stress

◆ _principal_stress_2

double GranOO3::DEM::Stress::_principal_stress_2

private

the value of the second (intermediate) principal stress

◆ _principal_stress_3

double GranOO3::DEM::Stress::_principal_stress_3

private

the value of the third (lower) principal stress

◆ _stress_tensor

Geom::SymTensor GranOO3::DEM::Stress::_stress_tensor

private

the main stress tensor which is updated by the compute_virial_stress() and the compute_lsq_stress() methods.

◆ _volume_fraction

double GranOO3::DEM::Stress::_volume_fraction

private

the volume fraction for computing virial stress (virial stress computation needs the real volume).

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

/home/granoo/granoo/Lib/GranOO3/DEM/Prop/Stress.hpp
/home/granoo/granoo/Lib/GranOO3/DEM/Prop/Stress.cpp
/home/granoo/granoo/Lib/GranOO3/DEM/Prop/Stress.dox

Public Member Functions

Private Member Functions

Private Attributes

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Stress()

◆ ~Stress()

Member Function Documentation

◆ add_criterion()

◆ compute_lsq_stress()

◆ compute_virial_stress()

◆ compute_virial_stress_for()

◆ criterion()

◆ get_hydrostatic_stress()

◆ get_tresca_stress()

◆ get_vonmises_stress()

◆ info()

◆ serialize()

◆ update_principal_stress()

Friends And Related Function Documentation

◆ boost::serialization::access

Member Data Documentation

◆ _criterion

◆ _criterion_list

◆ _include_velocity

◆ _neighbour_level

◆ _periodic

◆ _principal_frame

◆ _principal_point

◆ _principal_quat

◆ _principal_stress

◆ _principal_stress_1

◆ _principal_stress_2

◆ _principal_stress_3

◆ _stress_tensor

◆ _volume_fraction