[DanielSP]

Hello folks

this is my first post here, I hope I don't break any rules!

I am a civil Engineer and M.SC. in structures Engineering and I model and design structures, mostly using FEM.

Right now I am interested in the concept behind the static modeling of changing structures. Some cases are really simple, for instance:

1) If you load a structure then remove some part of it while keeping the same load, then the new moments, shear forces and strains can be easily obtained by simply ignoring the original structure. You load the new structure and that's it.

2) If you apply Load 1 on Structure 1, then add a structural element to it and finally apply a new Load 2, then the final state of forces and displacements is obtained by adding L1 on Structure 1 to L2 on structure 2.

No big deal here. But what if after loading the structure, you add a new part and then remove an old one?

[DanielSP]

I did, yes!