Geotechnical design and analysis Subject:
Bugs in PLAXIS??
Can someone explain this?
In some cases, when I view the stresses along a section in table format in PLAXIS, it gives me two stress values at a single coordinate.. Is this possible? And the difference is almost about 5 to 6 units in some cases. As far as I am aware, FEM should yield unique values, right?
If you have exact coordinates with different stress values, there is a bug in plaxis. However, if you made two lines at similar places, you will find much different stress results in plaxis.
The reason for that (at my oppinion) is the way, how plaxis calculate the stress state. It depends from element size, shape, density, stress state.....
My advice to you is, to do at the place of interest as much dens mesh as you can. The results then should be better. If not, dont bother much with that. Just make a few lines at the observed area, close to the each other, and then determine the stress, which is somewhere in the middle, as reference stress (the right one). Or even better, dont use a stress along a line in plaxis as a reference quantity. Use moments, shear and axial forces in support elements, or contour options for mesh measurements.