chrono::fea::ChElasticityCosseratAdvancedGeneric Class Reference

Description

Advanced linear elasticity for a Cosserat section, not assuming homogeneous elasticity.

This is the case where one uses a FEA preprocessor to compute the rigidity of a complex beam made with multi-layered reinforcements with different elasticity - in such a case you could not use ChElasticityCosseratAdvanced because you do not have a single E or G, but you rather have collective values of bending/shear/axial rigidities. This class allows using these values directly, bypassing any knowledge of area, Izz Iyy, E young modulus, etc. This material can be shared between multiple beams. The linear elasticity is uncoupled between shear terms S and axial terms A as to have this stiffness matrix pattern:

 n_x   [A       A A ]   e_x
 n_y   [  S S S     ]   e_y
 n_z = [  S S S     ] * e_z
 m_x   [  S S S     ]   k_x
 m_y   [A       A A ]   k_y
 m_z   [A       A A ]   k_z
 

#include <ChBeamSectionCosserat.h>

Inheritance diagram for chrono::fea::ChElasticityCosseratAdvancedGeneric:
Collaboration diagram for chrono::fea::ChElasticityCosseratAdvancedGeneric:

Public Member Functions

 ChElasticityCosseratAdvancedGeneric (const double mAx, const double mTxx, const double mByy, const double mBzz, const double mHyy, const double mHzz, const double malpha, const double mCy, const double mCz, const double mbeta, const double mSy, const double mSz)
 
virtual void SetAxialRigidity (const double mv)
 Sets the axial rigidity, usually A*E for uniform elasticity, but for nonuniform elasticity here you can put a value ad-hoc from a preprocessor.
 
virtual void SetXtorsionRigidity (const double mv)
 Sets the torsion rigidity, for torsion about X axis, at elastic center, usually J*G for uniform elasticity, but for nonuniform elasticity here you can put a value ad-hoc from a preprocessor.
 
virtual void SetYbendingRigidity (const double mv)
 Sets the bending rigidity, for bending about Y axis, at elastic center, usually Iyy*E for uniform elasticity, but for nonuniform elasticity here you can put a value ad-hoc from a preprocessor.
 
virtual void SetZbendingRigidity (const double mv)
 Sets the bending rigidity, for bending about Z axis, at elastic center, usually Izz*E for uniform elasticity, but for nonuniform elasticity here you can put a value ad-hoc from a preprocessor.
 
virtual void SetYshearRigidity (const double mv)
 Sets the shear rigidity, for shear about Y axis, at shear center, usually A*G*(Timoshenko correction factor) for uniform elasticity, but for nonuniform elasticity here you can put a value ad-hoc from a preprocessor.
 
virtual void SetZshearRigidity (const double mv)
 Sets the shear rigidity, for shear about Z axis, at shear center, usually A*G*(Timoshenko correction factor) for uniform elasticity, but for nonuniform elasticity here you can put a value ad-hoc from a preprocessor.
 
void SetSectionRotation (double ma)
 Set the rotation in [rad] of the Y Z axes for which the YbendingRigidity and ZbendingRigidity values are defined.
 
double GetSectionRotation ()
 
void SetCentroid (double my, double mz)
 "Elastic reference": set the displacement of the elastic center (or tension center) respect to the reference section coordinate system placed at centerline.
 
double GetCentroidY ()
 
double GetCentroidZ ()
 
void SetShearRotation (double mb)
 Set the rotation in [rad] of the Y Z axes for which the YshearRigidity and ZshearRigidity values are defined.
 
double GetShearRotation ()
 
void SetShearCenter (double my, double mz)
 "Shear reference": set the displacement of the shear center S respect to the reference beam line placed at centerline. More...
 
double GetShearCenterY ()
 
double GetShearCenterZ ()
 
virtual void ComputeStress (ChVector<> &stress_n, ChVector<> &stress_m, const ChVector<> &strain_e, const ChVector<> &strain_k) override
 Compute the generalized cut force and cut torque. More...
 
virtual void ComputeStiffnessMatrix (ChMatrixNM< double, 6, 6 > &K, const ChVector<> &strain_e, const ChVector<> &strain_k) override
 Compute the 6x6 tangent material stiffness matrix [Km] = dσ/dε. More...
 

Additional Inherited Members

- Public Attributes inherited from chrono::fea::ChElasticityCosserat
ChBeamSectionCosseratsection
 

Constructor & Destructor Documentation

◆ ChElasticityCosseratAdvancedGeneric()

chrono::fea::ChElasticityCosseratAdvancedGeneric::ChElasticityCosseratAdvancedGeneric ( const double  mAx,
const double  mTxx,
const double  mByy,
const double  mBzz,
const double  mHyy,
const double  mHzz,
const double  malpha,
const double  mCy,
const double  mCz,
const double  mbeta,
const double  mSy,
const double  mSz 
)
inline
Parameters
mAxaxial rigidity
mTxxtorsion rigidity
mByybending regidity on Y of reference at elastic center
mBzzbending rigidity on Z of reference at elastic center
mHyyshear rigidity on Y of reference at shear center
mHzzshear rigidity on Y of reference at shear center
malpharotation of reference at elastic center, for bending effects [rad]
mCyelastic center y displacement respect to centerline
mCzelastic center z displacement respect to centerline
mbetarotation of reference at shear center, for shear effects [rad]
mSyshear center y displacement respect to centerline
mSzshear center z displacement respect to centerline

Member Function Documentation

◆ ComputeStiffnessMatrix()

void chrono::fea::ChElasticityCosseratAdvancedGeneric::ComputeStiffnessMatrix ( ChMatrixNM< double, 6, 6 > &  K,
const ChVector<> &  strain_e,
const ChVector<> &  strain_k 
)
overridevirtual

Compute the 6x6 tangent material stiffness matrix [Km] = dσ/dε.

Parameters
K6x6 stiffness matrix
strain_elocal strain (deformation part): x= elongation, y and z are shear
strain_klocal strain (curvature part), x= torsion, y and z are line curvatures

Reimplemented from chrono::fea::ChElasticityCosserat.

◆ ComputeStress()

void chrono::fea::ChElasticityCosseratAdvancedGeneric::ComputeStress ( ChVector<> &  stress_n,
ChVector<> &  stress_m,
const ChVector<> &  strain_e,
const ChVector<> &  strain_k 
)
overridevirtual

Compute the generalized cut force and cut torque.

Parameters
stress_nlocal stress (generalized force), x component = traction along beam
stress_mlocal stress (generalized torque), x component = torsion torque along beam
strain_elocal strain (deformation part): x= elongation, y and z are shear
strain_klocal strain (curvature part), x= torsion, y and z are line curvatures

Implements chrono::fea::ChElasticityCosserat.

◆ SetShearCenter()

void chrono::fea::ChElasticityCosseratAdvancedGeneric::SetShearCenter ( double  my,
double  mz 
)
inline

"Shear reference": set the displacement of the shear center S respect to the reference beam line placed at centerline.

For shapes like rectangles, rotated rectangles, etc., it corresponds to the elastic center C, but for "L" shaped or "U" shaped beams this is not always true, and the shear center accounts for torsion effects when a shear force is applied.


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono/fea/ChBeamSectionCosserat.h
  • /builds/uwsbel/chrono/src/chrono/fea/ChBeamSectionCosserat.cpp