InelJ2PwLH2dMat

Purpose

inelastic 2d material with J2 plasticity under linear kinematic and isotropic hardening

Synopsis

MatResp = InelJ2PwLH2dMat (action,MatNo,MatData,MatState)

Description

INELJ2PwLH2DMAT inelastic 2d material with J2 plasticity under linear kinematic and isotropic hardening
  MATRESP = INELJ2PwLH2DMAT (ACTION,MAT_NO,MATDATA,MATSTATE)
  function determines the stress-strain relation for an inelastic 2d material
           with J2 plasticity under linear kinematic and isotropic hardening
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  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'
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  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
         Case    = 'stress' for plane stress, 'strain' for plane strain, or 'general'(empty)
         irs     = stress components to be retained for the general Case
         tol     = tolerance value for stress condensation
         maxiter = maximum number of iterations for for stress condensation
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  MATPOST is a data structure with material response information for post-processing in fields
         eps   =   total strain(4x1)
         sig   =         stress(4x1)
         eps_p = plastic strain(4x1)

Cross-Reference Information

This function calls:

• Condense_MV condense matrix Kf and vector Pf to a reduced set idr of degrees of freedom
• InelJ2PwLH3dMat inelastic 3d material model with J2 plasticity and linear kinematic and isotropic hardening