Hello.

Im newbie to this forum, but used it sometimes to solve doubts and problems.

Actually i've to study a system, using Caesar 2011 through 31.1

I've been noticed that when i use hanger in the exp load case the system doesn't show any overstress node, but just when i don't use any hanger, the system shows overstress in the exp load case.

How can it be?!, the exp case doesn't have the "H"!!! With ir without the use of any hanger, so why the system shows overstress in exp load case depending if i used ir not a hanger???. I think that for exaple in sustained cases i must get different results, but in the exp case the result must be the same.

Thank you in advance

You don't "just" have a hanger in the EXP case - either you have a hanger in your system (all load cases), or you don't (no load cases).

The EXP case is the difference (i.e. the range) between two other load cases. You shouldn't have a hanger in one and not the other.

Richard, thank you for your answer.

Sorry, but i can{t understand quite well what you said.

Generally in a system using hangers:

HGR: W
HGR: W+P1+T1
OPE: W+P1+T1+H
SUS: W+P1+H
EXP: OPE-SUS=T1.

The system that i´m refereing to, already has two springs (automatically selected by Caesar, not predefined), and i'm planing to use another one more. But while i've been working on this, then this situation become strange to me, maybe is something wrong with my understanding of how the load cases works, etc..,

So resuming: the system with 3 hangers goes OK, without any overstress, but when i "eliminate" one of the three hangers, then overstress appears in EXP load case, the question is: Should this overstress also appears using this hanger????. I think EXP load case doesn´t takes care about the use of hangers..( it doesn´t considers the "H"...), for the exp load case, hangers doesn´t exists, am i correct???. If not, could you please explain this?.

Thank you

Your load cases are fine. "OPE-SUS" does not necessarily equal "T1", it depends on the degree of non-linearity of the system.

The EXP case is based on the "displacement range", computed from the OPE displacements minus the SUS displacements. So the effect of the hangers on the OPE case and the SUS case are included.

Thank you again Richard, now it makes sense to me.

It seems that i must learn more aboute the "non-linearity" to understand how it works.