Recently, I have been working on the simulation of a pile-soil interaction with CEL method in Abaqus/Explicit. I simulate the sand with the Sand Hypoplasticity Model provided by Prof. Masin. And I use the VUMAT_UMAT Interface from Prof. Bienen.
However, When I call the Vumat.for file, two errors always appears:
Error 1: The option *user material,type=mechanical completely defines the material behavior. It can not be used with an option that defines part of a material`s behavior
Error 2: A material property that is not allowed with a user material has been specified
PS: The picture shows the error message and the sand constitutive model parameters setting.
I did not find a solution to these two errors on the Internet, so I ask for help. Any suggestion or comment will be appreciated.