I have heard from several sources that the NorSand model performs better in Plaxis than in FLAC, in terms of deformation models, for example in static analysis of tailings deposits. This is due to the FLAC solution process. How true is this?

I’m not sure about Plaxis, but I have had success using NorSand for static analyses of tailings dams in FLAC3D v7 and FLAC2D v9. For dynamic, something like PM4Sand/PM4Silt is preferred but NorSand also works.

In what way do you mean performs better though? In terms of solving time or accuracy? For uncoupled static problems the solving time for NorSand (~30k zones) is inconsequential. For accuracy, we hope that FLAC and Plaxis give the same results for the same inputs of course.

What I can say is that NorSand in FLAC performs very well for single element simulation of critical state triaxial tests for calibration and for ‘full-scale’ problems generally I find that the deformations are a bit overestimated, but the stress and state (void ratios) are very realistic.

Thank you very much for your reply Paul. My question was about the accuracy of the results in terms of strains and stresses for static problems.

It would be interesting to compare results from calibrated tailings dam models with the same properties in both softwares.