my question is about the history data storage in FEAP.
I am writing element subroutine (elmt01) in FEAP 8.3 for a history dependent problem.
I have written the stiffness matrix subroutine (stiff01), but it needs the data from the previous solution steps (previous strains, stresses, plastic strains, dislocation densities .... nh1,nh2=30 per point).
I am using FEAP 8.2 in my university, and have to write a user material routine, but there is no clear guideline/example about which files to modify for this purpose. Sorry to say, the programmer's manual is very short, and very little detail is there.
I am a newbie in FEAP and I would like to perform transient heat transfer analysis followed by a series of static analysis using FEAP. Where does FEAP save the temperature history from the transient analysis and how to use this as input for the static analysis? I am using user constitutive model and most of the material parameters are temperature dependent. Which file do I need to include?
The difference to the common model used is the f,g terms. The 3D FEM formulation has been derived and a new fortran program is written. The derivative matrix is symmetric. But the calculation result does not converge. I have tried every means to get a converging result. But it doesn't work, the residual norm always increases.