topic Re: Dead load automaticly applied to live load cases in Robot Structural Analysis Forum

Dead load automaticly applied to live load cases

tomas.jonebratt — Tue, 04 Apr 2023 11:12:50 GMT

These are my my applied loads.

I have multiple differend load types assigned

My dead load comes out to the following total reaction (in results "Reactions"):

However when i keep checking further down all my load cases seem to automaticaly have the dead load applied to them as well:

My SN1 combination wich has a total applied load of 36,87kN show the following which shows that the dead load is also applied here:

Why is this the case and how do i get rid of the dead load from all cases except case 1?

Follow up question. Since the dead load is applied to all cases, wouldnt that mean that in my combinations the dead load is applied multiple times?

Re: Dead load automaticly applied to live load cases

Romanich — Tue, 04 Apr 2023 11:16:21 GMT

Hi @tomas.jonebratt ,

Did you try to open your model using Repair Mode?

Re: Dead load automaticly applied to live load cases

tomas.jonebratt — Tue, 04 Apr 2023 11:20:27 GMT

I tried that now, it did not help. I also made a new identical model, both had the same issue.

Re: Dead load automaticly applied to live load cases

Romanich — Tue, 04 Apr 2023 11:21:37 GMT

Could you please share the model? Zip it first.

Re: Dead load automaticly applied to live load cases

tomas.jonebratt — Tue, 04 Apr 2023 11:25:31 GMT

I did another quick test now. I had some "Cable"-elements in my project. When i removed these all the dead load disapeared from the live load cases. Any idea why this is? And if i want to have cables in my structure, how would i do this without causing this problem?

Re: Dead load automaticly applied to live load cases

Rafacascudo — Tue, 04 Apr 2023 11:31:09 GMT

That's it. Using cables triggers the "assembling case" which means all the following cases will have the addition of the cable " loading " + the 1st load case created by you ,in your model SW.

Re: Dead load automaticly applied to live load cases

tomas.jonebratt — Tue, 04 Apr 2023 11:35:55 GMT

ooh ok thanks! Thats a weird setting?

Could i model the cables using bars somehow but only let them work in traction, not pressure so that i can use "cables" anyway?

Re: Dead load automaticly applied to live load cases

Rafacascudo — Tue, 04 Apr 2023 13:06:41 GMT

Using cables means nonlinear analysis., and it will always work the way I described.
Good information here
https://help.autodesk.com/view/RSAPRO/2023/ENU/?guid=GUID-EFD9944A-DCF3-41C3-93DA-330FBA7FFF07

If you just want a "tension only" bar,you can use "advanced bar properties" to make it a "tension only" truss bar , on Geometry/additional atributes. It will also be a nonlinear analysis , but no including of undesired extra load cases into your other cases