Material_Library > 3dMaterials > InelGJ2P3dMat
InelGJ2P3dMat
Purpose
3d generalized J2 plasticity material model
Synopsis
MatResp = InelGJ2P3dMat (action,MatNo,MatData,MatState)
Description
INELGJ2P3dMAT 3d generalized J2 plasticity material model
MATRESP = INELGJ2P3dMAT (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
Reference: Aurrichio/Taylor,International Journal of Plasticity, vol.11, pp.65-98,1995
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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
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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'
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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
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MATDATA is a data structure with material property information; it has the fields
E = initial modulus
fy = yield stress
nu = Poisson's ratio
Hi = isotropic hardening modulus
Hk = kinematic hardening modulus
delta = measures the speed of the material approaching the asymptotic behavior
phi = a scalar measure of the distance between the asymptotic and the current radius of the yield function
Hnl = nonlinear kinematic hardening parameter
HRule = hardening rule (Options: 'LP','GP','NLK')
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MATPOST is a data structure with material response information for post-processing in fields
eps = strain tensor in 6x1 vector form in the order 11, 22, 33, 12, 13, 23
sig = stress tensor in 6x1 vector form in the order 11, 22, 33, 12, 13, 23
eps_p = plastic strain tensor in 6x1 vector form in the order 11, 22, 33, 12, 13, 23
Cross-Reference Information
This function calls:
- Hardening library of hardening functions for plasticity models
- InelGJ2PStrConstr3dMat 3d general plasticity J2 material under constrained stress state