Hello,
I am modeling a small scale uplift test which was conducted on a circular plate embedded inside a sand bed. The circular plate was of diameter 75 mm and depth of the embedment was 750 mm. The same was modeled in PLAXIS 3D using plate element and hardening soil model for the sand. The uplift was provided on the plate using the surface displacement.
I have plotted the load displacement behavior obtained from the experimental and PLAXIS. It can be seen the numerical model does not capture the failure of anchor plate (the curve gradually becoming flatter after a certain displacement as seen in the experimental curve).
Please suggest where I may have gone wrong in terms of modelling or am I missing something here.
I have also tried to provide an interface to the plate however similar result do not change much. I did note that for lower depth of plate (around 400 mm) the curve from the PLAXIS 3D did flatten after some displacement.
The numerical properties of sand were as follows
E50 = 30000, Eoed = 30000, Eur = 90000, m = 0.5, c = 0.1 Kpa, phi = 35
The load-displacement behaviour obtained from the model is dependent on the material properties, mesh, and boundary conditions. The modelling results suggests that the soil has a softer response between the initial displacements from 0 to 5 mm. Increasing the E50 value will make it match more closely to the experimental result. Beyond 5 mm the experimental result becomes flatter. In this part, adjusting the m parameter or C or Phi of the material to lower values will give a more flatter curve.
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