Continue Loads through subcases

Arno Heidkamp

I want to do a non-linear analysis with subsequent loading:

• Subcase 1
  • Prestress
• Subcase 2
  • cont. Prestress 
  • Load 1
• Subcase 3
  • cont. Prestress
  • Continue load 1
  • add load 2

I found that CNTNLSUB carries over the stresses and strains from previous subcase, but not the load.

Then, if stresses&strains are carried over, but the load starts from scratch, there will be a discontinuity, won't there?

I wonder which combination is correct:

• Subcase 1
  • Prestress
• Subcase 2
  • CNTNLSUB(1)
  • Load 1

AND

• Subcase 3 (I expect a different load path here, becaue Load 1 will start from zero again and will be lineary superimposed to Load 2)
  • CNTNLSUB(1)
  • LOADADD(Load 1, Load 2)

OR

• Subcase 3 (if the above said is true, then the stresses and (linear) strains from Load 1 will have disappeared at the end of this subcase)
  • CNTNLSUB(2)
  • Load 2

OR

• Subcase 3 (I expet a discontinuity here, because Load 1 will start from zero again, while the corresponding stresses & strain are carried over)
  • CNTNLSUB(2)
  • LOADADD(Load 1, Load 2)

 

RobinsonFerrari

Hello Heidkamp,

If you do your first example (LOADADD), load 1 will not start from zero. You will only add load 2 in this case. So, this should be the right option for your case.

Please try this in a small deck and let me know if it works for you. Otherwise, attach your deck and I can take a look.

Thank you,