Dear community, I'm trying to find the ultimate bearing capacity of a shallow footing in PLAXIS 3D.
The analysis is made as Load Control: A weightless plate element (2x2) is created with a point load of 10,000 kN at its center (shear failure guaranteed).
The curve of Mstage vs IuI is drawn for a pre-calculated node at the footing's center, and the ultimate load is extracted as Mstage x 10,000 for the point at which the curve becomes parallel to the axis of IuI (shear failure occurs).
However, I'm having doubts about this method of reading the curve when dealing with a loose sand or soft clay, where Local or Punshing Shear Failure are expected to happen as shown the below picture.
I understand that the MC model does not includes softening of soil as a hypo-plastic model would, however there should be a method to get the ultimate capacity from the MC model given that even in the two cases above, the curve I'm having converges to a clear maximum load.
Would you recommend that I continue using the same approach for Dense and Loose soil?
Thanks a lot!