Python material setproperties

Hi all,

I am diving into the creation of PLAXIS 2D models using Python. I have some experience with the scripting engine and have read and studied the material provided by the commands reference.

I am stuck creating soil materials in my Python script. For clarity I follow the syntax provided by the example on page 533 of Plaxis 2D reference manual:

SAND_PARAMETERS = [
('MaterialName', 'Sand'),
('Colour', 10676870),
('SoilModel', 3), # Hardening soil
('DrainageType', 'Drained'),
('gammaUnsat', 17),
('gammaSat', 20),
('E50ref', 43000),
.....

This is a very robust definition, for all values have their parameter names defined as labels and PLAXIS 2D is processing this syntax correctly!

I am stuck for I haven't found the full definition of the labels anywhere, and I have spend time guessing some of the labels, but that has not been successful, so I hope someone will be able to help me and supply the labels for these values:

  • flow parameter kx
  • flow parameter ky
  • advanced stiffness E'inc
  • advanced stiffness yref

Using ('SoilModel', 2), # Mohr-Coulomb

Thank you in advance!

Kind regards, G.J. Kiers

Parents Reply Children
  • Dear Stefanos,

    Whilst the autocomplete function has made things easier, I am still struggling to find a way to add some parameters when using a Python script.

    When picking between different ground models, the command line adjusts to the parameters that where used.  Some are clearly identified whilst others are still ‘hidden’.  As an example, when working with Mohr-Coulomb Undrained (B) we are asked to specify parameter su,ref (undrained shear strength), which for my case is 15 kPa.  In the command line, the value of su,ref appears in the middle of other parameters with no identification.  Here is an extract of the command line: … "Einc" 0 "CVRef" 0.02592 10000 0 0 15 0 0 0 0 18.5 18.5 1.296E-5 1.296E-5 1 1.296E-5 0 0 0 0 0 0.333333333333333 0 0.999 0 0 0 0 1.0000000000000000E+015 0.495 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 …  I have also noticed that the Unsaturated and Saturated soil density, identified as 18.5 kN/m3 are also not identified for this constitutive model.

    Is there a way to get a list of reference names for parameters that are still not identified in the command line, so those can be specified via a Python script?

    Kind regards,

    Joao

  • Dear Joao,

    The material command generated when using the GUI includes all parameters, even ones that are not really used. The command response is long and its signature is quite complex, which you do not necessarily need to follow.

    The starting point for every material is the following article that covers the minimum set of parameters that need to be defined:
    https://communities.bentley.com/products/geotech-analysis/w/plaxis-soilvision-wiki/45969/plaxis-soil-model-numbers-in-command-line

    The object you can check on our documentation is called SoilMat.

    In general, it is good to have the parameters in a sequence of < parameter name - parameter value >. Note that of course there are some dependencies of parameters, e.g. when you change the friction angle, the K0 value by default will be computed, too.

    If you have a specific issue, it is easier for us to assist you via a service request: https://apps.bentley.com/srmanager/ProductSupport

  • Dear Stefanos,

    Thank you for the explanation.  The minimum number of parameters that needs to be defined for each consitutive model is a usefull .

    One possible solution is to assess what works for Plaxis by running a few tests, i.e. changing a parameters and observe the result in the command line - which is something that has been recommended in this forum a few times.

    Thank you for the link to service request manager. I will use it when applicable.

    Best regards,

    Joao

  • Hello Joao,

    That is correct for almost everything in PLAXIS, but the material command always generates the whole set of parameters, as a material definition is a collection of parameters that together forms the definition of the constitutive model to be used.

    Therefore, the approach of changing, for instance, the friction angle, to see the command generated is not the same an with the rest of the program.

    Since many of the cases with materials can be very specific to what you try to do, it is easier and faster to handle it via a service request, so let us know when you encounter any difficulty.