currently i being study the parameters input for Drucker Prager Cap models. most of all these values can be derived from Modified Mohr Colomb paramaters, except in ratio of elliptical cap ( R ) to get pb values.
i try seeking any literature, but did not found a theoretical background and used consistent values. some researcher use 0.2 and 0.6 others, is there any guidance for these values in correlation with concrete compressive strength?
even i’m not really confident to enter in advanced damage material forums, still i try and do stepped learning curves.
i have a great news from Thomas H. the authors of TFEL/MFront, some newest and updates of Mazars material models has been implemented. it’s called UnilateralMazars.mfront and stored at his GitHub, may it possible to add to the list for next release of CalculiX/MFront interfaces? thank you much.
*Material, name=@CALCULIXBEHAVIOUR_UNILATERALMAZARS
*Depvar
6
** The material properties are given as if we used parameters to explicitly
** display their names. Users shall replace those declaration by
** theirs values
*User Material, constants=9
<YoungModulus>, <PoissonRatio>, <At>, <Bt>, <Ac>, <Bc>, <st_max>, <sc_max>,
<k>
UnilateralMazars.mfront form tfel-master\mfront\tests\behaviours
It works on my computer, so it may be a problem that this version is not fully portable.
I have no way to check, I only have access to computers with the same processor architecture: Intel Haswell.
I use portable build flags but maybe some is missing (http://tfel.sourceforge.net/faq.html#portable-build).
For compilation Mfront:
-Denable-portable-build=ON
and for material library:
mfront --obuild=level0
PS.
If the location of the Mfront library is not indicated then this error occurs (unable to load library).
You can add to cmdStartup.bat (for example): set PATH=%CALCULIX_ROOT%\CalculiX\MFront;
Or simply copy all .dll file to folder where is ccx.exe
may the processor compatibility since i’m using AMD. the path is already defined correctly, as seen DruckerPrager and Mazars seems work well. unfortunately the last two i interest did not.
hope, the problem will be found and fixed someday.
I was able to run cxx+mfront according to your directions but the frd file has no results included. I will go ahead again and check output paramenters. Thank you very much.
I successfully linked CCX+MFRONT on MECWAY. And I added extra ccx-cards to handle MFRONT materials inside the GUI.
I found out that if you want to use the same material, for example MAZARS, several times in the .inp file, you must add the new name as a suffix this way(: @CALCULIXBEHAVIOUR_UNILATERALMAZARS@CLAY @CALCULIXBEHAVIOUR_UNILATERALMAZARS@CONCRETE
I carry out the calculation adding your card (thank you) and CCX gives me SDV parameters with values included but I still do not get displacements neither stresses.
I still do not get displacements, what a pitty.
I think I am using a wrong unit system. I use MECWAY as GUI and all the internal parameters must be in N,m,kg,ºK.
I found an useful Mazar material definition excel spreadsheet on Code_aster forum that plots the stress/strain curve.
I have a couple of questions for you:
Does Mazar material definition on MFRONT use any unit system or it is agnostic?
Do you know if my next assumption on units is right?