I wanted to do this, but displacement doesn’t have an amplitude. Displacement only has a local coordinate system. Amplitude is for forces.
Displacement/Rotation BC may also use amplitude, but you have to create it first and then it will be selectable.
1 Like
Sorry, I forgot that these options disappear if there are no definitions 
I don’t like this behavior of the program. I don’t always do everything in order. Thanks for the suggestion.
“…Your model is exhibiting exactly the correct behavior: at around 20% of the load (~20 MPa), the cross section has completely yielded and has no additional stiffness to support the load further. Therefore it does not and can not converge…”
Right, perhaps it would be good to always show them. But then the panels could become a bit crowded with amplitude (film and radiation have 2), distributions and local coordinate system selectors.
1 Like
It is possible and it’s a common reason of non-convergence when modeling approach is correct and damage/fracture is not taken into account. But you would have to check PEEQ - plastic strain (how much the cross-section yielded in %). In my tests, PEEQ reached a few percent. But you could confirm it with a simplified approach using pressure.
1 Like
When you can see all the fields, it is much easier to understand how the program works.
Works better with shells ? What type of element ?
S8R, contact only with the indenter:
Reaches 0.2438 s
Maybe more layers (composite section) would be better, but then we can just use solids directly.
1 Like
Nice! What n and alpha did you choose ? What are the plastic strains (PE / PEEQ) ?
For me, it still diverges with this model, so I guess other changes matter too.
This is my first model posted here. I only changed the material to Ramberg–Osgood. I forgot to introduce PEEQ and reduce the contact areas. I assumed that since plasticity couldn’t produce a result, I needed to make a larger change.
Just with shells instead of solids ? Your original model with solids reaches 0.56675 s for me with R-O plasticity.
Shell + material Ramberg–Osgood.
Material = Solid + Ramberg–Osgood
Reduced first-order elements
Contact = soft
+
SUMMARY OF C0NVERGENCE INFORMATION
STEP INC ATT ITER CONT. RESID. CORR. RESID. CORR.
EL. FORCE DISP FLUX TEMP.
(#) (%) (%) (%) (%)
1 1 1 1 1968 0.2556E+05 0.1000E+03 0.0000E+00 0.0000E+00
1 1 1 2 2048 0.2042E+05 0.1999E+02 0.0000E+00 0.0000E+00
1 1 1 3 2822 0.8776E+05 0.1000E+03 0.0000E+00 0.0000E+00
1 1 1 4 14556 0.2237E+06 0.3775E+02 0.0000E+00 0.0000E+00
1 1 2 1 1968 0.1520E+05 0.1000E+03 0.0000E+00 0.0000E+00
1 1 2 2 2480 0.1797E+05 0.4723E+02 0.0000E+00 0.0000E+00
1 1 2 3 2560 0.1131E+06 0.1000E+03 0.0000E+00 0.0000E+00
1 1 2 4 2642 0.1036E+06 0.3410E+02 0.0000E+00 0.0000E+00
1 1 2 5 2950 0.1037E+06 0.3354E+02 0.0000E+00 0.0000E+00
1 1 2 6 2562 0.7637E+05 0.4804E+02 0.0000E+00 0.0000E+00
1 1 2 7 2490 0.3771E+06 0.1000E+03 0.0000E+00 0.0000E+00
1 1 2 8 1772 0.3776E+06 0.2842E+02 0.0000E+00 0.0000E+00
1 1 3 1 1968 0.1719E+05 0.1000E+03 0.0000E+00 0.0000E+00
1 1 3 2 2000 0.1193E+04 0.1645E+01 0.0000E+00 0.0000E+00
1 1 3 3 1856 0.1129E+04 0.1300E+01 0.0000E+00 0.0000E+00
1 1 3 4 1856 0.6929E-01 0.7283E-02 0.0000E+00 0.0000E+00
1 1 3 5 1856 0.1340E+05 0.6457E+01 0.0000E+00 0.0000E+00
1 1 3 6 1680 0.8282E+04 0.4024E+01 0.0000E+00 0.0000E+00
1 1 3 7 1536 0.9999E+04 0.4956E+01 0.0000E+00 0.0000E+00
1 1 3 8 1472 0.5894E+03 0.1217E+01 0.0000E+00 0.0000E+00
1 1 3 9 1408 0.2110E+03 0.6233E+00 0.0000E+00 0.0000E+00
1 1 3 10 1408 0.8781E-01 0.8127E-02 0.0000E+00 0.0000E+00
