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Non-convergence because of excessive distortion

Non-convergence because of excessive distortion

Non-convergence because of excessive distortion

(OP)
My model does not converge because of (I think) excessive
distortion. Below is what I get from the msg.file
Please advise me how can I overcome this issue

               EQUILIBRIUM ITERATION     2

AVERAGE FORCE  1.642E+05   TIME AVG. FORCE    1.642E+05

LARGEST RESIDUAL FORCE -1.283E+04   AT NODE  3864 DOF  2

LARGEST INCREMENT OF DISP.   -0.273  AT NODE 8302 DOF 2

LARGEST CORRECTION TO DISP.0.128  AT NODE  8302   DOF  2
  
FORCE EQUILIBRIUM NOT ACHIEVED WITHIN TOLERANCE.

RE: Non-convergence because of excessive distortion

Try decreasing the initial, minimum and maximum time increments.

RE: Non-convergence because of excessive distortion

(OP)

Playing with the initial, minimum and maximum time increments couldnot solve the issue.
I am puzzeled about what the solver does when getting non-positive definite matrix (negative or zero stiffness matrix determinate) that could arise , for example,  due to material softening/failure. Keep aside the technique used in Riks Step as I can not use this step.
 
Here is some warning massege I am getting during the job run
"The plasticity/creep/connector friction algorithm did not converge at 1 points

Program is asked to invert a singular matrix"

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