User subroutine for modeling transient swelling of hydrogels with Abaqus

The dataset contains two files:
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1) UMAT_swelling_gels.for -- A Fortran routine defining the constitutive relations for transient
gel swelling. To be used with the commercial finite element solver Abaqus 6.14.
All simulation parameters are defined in the USDFLD subroutine.

2) gel_plate_buckling.inp -- An example input file for swelling of a confined layered plate sketched in
milimeters and with a random intial imperfection in its upper surface.
To be used with Abaqus 6.14.

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The files in this dataset were used to produce the results presented in "Buckling initiation in layered
hydrogels during transient swelling" by A. Ilseng, V. Prot, B.H. Skallerud, and B.T. Stokke
published in "Journal of Mechanics and Physics of Solids" in 2019.

Note that you need to link Abaqus to a Fortran compiler in order to run the model with the user subroutine.

These files are distributed in the hope that they will be useful.
The authors assume no responsibility for possible errors.