InelGJ2PStrConstr3dMat

Purpose

3d general plasticity J2 material under constrained stress state

Synopsis

MatResp = InelGJ2PStrConstr3dMat (action,MatNo,MatData,MatState)

Description

INELGJ2PCONSTR3DMAT  3d general plasticity J2 material under constrained stress state 
  MATRESP = INELGJ2PCONSTR3DMAT (ACTION,MATNO,MATDATA,MATSTATE)
  the function determines the stress-strain relation for 3d material
  under different hardening rules for J2 yield surface with isotropic and kinematic hardening
  under specified constrained 3d stress state
  Reference: Aurrichio/Taylor,International Journal of Plasticity, vol.11, pp.65-98,1995
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  the character variable ACTION should have one of the following values
  ACTION = 'chec' function checks material property data for omissions and returns default values in MATDATA
           'init' function returns the material history variables in MATSTATE
           'forc' function returns the material stress (tensor) in MATSTATE
           'stif' function returns the material tangent modulus and the stress (tensor) in MATSTATE
           'post' function returns data structure MATPOST with post-processing information
  depending on the value of character variable ACTION the function returns information in data structure MATRESP
  for the material with number MAT_NO; data structure MATDATA supplies the material property data
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  data structure MATRESP stands for one of the following data objects depending on value of ACTION 
  MATRESP = MATDATA   for action = 'chec'
  MATRESP = MATSTATE  for action = 'init'
  MATRESP = MATSTATE  for action = 'stif'
  MATRESP = MATSTATE  for action = 'forc'
  MATRESP = MATPOST   for action = 'post'
  MATRESP is empty    for action = 'data' and for unsupported keywords
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  MATSTATE is a data structure with information about the current material state in fields
         eps    = total strain (tensor for 2d or 3d)
         Deps   = strain increments from last convergence
         DDeps  = strain increments from last iteration
         epsdot = strain rate (tensor for 2d or 3d)
         km     = material stiffness matrix; returned under ACTION = 'stif'
         sig    = stress (tensor for 2d or 3d); returned under ACTION = 'stif' or 'forc'
         Past   = material history variables at last converged state
         Pres   = current values of material history variables
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  MATDATA is a data structure with material property information; it has the fields
         E  = initial modulus
         fy = yield strength
         nu = Poisson ratio
         Hi = isotropic hardening modulus
         Hk = kinematic hardening modulus
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  MATPOST is a data structure with material response information for post-processing in fields
         eps = total strain
         sig = stress (6x1)

Cross-Reference Information

This function calls:

• InelGJ2P3dMat 3d generalized J2 plasticity material model
• Condense_k condense matrix K to a reduced set idr of dofs by condensing out dofs idc