With the release of PLAXIS 2D CONNECT Edition V21 , a new Soil Model for cyclic mobility and liquefaction analysis is introduced: the PM4Silt model (Boulanger & Ziotopoulou, 2018).
PM4Silt is a stress-ratio controlled, critical state compatible, bounding surface plasticity constitutive model formulated recently by Boulanger and Ziotopoulou at the University of California, Davis. PM4Silt is suitable for simulating the response of low-plasticity silts and clays in geotechnical earthquake engineering applications. The model enhances the framework used for PM4Sand, a constitutive model for cyclic liquefaction of sands and non-plastic silts already available with PLAXIS 2D, to predict the features of undrained monotonic and cyclic loading responses, typical of those soils exhibiting stress history normalized mechanical behavior. It can reproduce the experimental evidence and empirical correlations of the undrained cyclic resistance across a wide range of initial shear and overburden stress conditions as well as the shear modulus decay and equivalent damping ratios.
Figure: Results from simulations of undrained cyclic DSS tests performed with two calibrations proposed for normally consolidated clayey silt and silty clay
More info:
- PM4Silt: Bentley Communities: PM4Silt model
- Full webinar on PM4Silt: Seismic Behavior of Fine-grained Soils Using PM4Silt (requires a Bentley account)
Dear Micha,
I tried to implement a unified dynamic soil model into PLAXIS, but it doesn’t calculate any strains, and it prints zero (or some times NaN amounts) into a text file. it causes PLAXIS doesn’t draw any plot in soil test part. I’d like to know the way of PLAXIS calculates the strains at the first step (initialing phase not finite element process).
I would be grateful if you give your opinion related to this problem.
Best Regards,
Nasim Aftahi
Hi Nasim, I answered your question in this thread: https://soilmodels.com/udsm-plaxis/
please see that to not have too many threads on the same topic. thanks
Micha