Sir, As a beginner of FRIC I am facing some difficulties to implement it. The downloaded FRIC code has been added to my pile soil friction model and trying to validate with the hypo plasticity model. I am confused about the input of hypo plastic properties. When i am giving the properties on User defined material properties i am getting the error as umat is not attached. Does this “FRIC .for” already included the umat.
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Dear Arun,
I will try to answer all your questions and a bit more.
1. The file Fric_HPvW is only the contact model which have a coding interface using the UMAT as a constitutive driver for the contact. But there is no UMAT attached. What you can do is to simply copy the UMAT.for for the hypoplastic model and attach it to the FRIC_HPvW.for file.
2. The abbreviation Fric_HPvW refers to the Hypoplastic model from von Wolffersdorff that is for granular media. Keep this in mind if you want to model fine-grained interfaces.
3. Please have a look to the UMAT documentation, because the second property is a numerical cohesion value. You have to follow the input for the properties.
4. You have to use the exact amount of parameters described in the documentation for the FRIC otherwise the subroutine will interrupt and you must specify the amount of state variables.
5. The state variables must also be defined for the UMAT use.