Seeking Guidance on Correcting ETABS Model Errors

[Abo Sa2er]

Dear Eng-Tips Community,

I'm relatively new to using ETABS for structural analysis and design, and I'm encountering difficulties in identifying and rectifying errors within my models. Despite my efforts, I have not found sufficient resources to bolster my knowledge, particularly in the area of checking models and resolving error messages.

I am seeking guidance from the experienced members of this community on how to empower myself in addressing these challenges effectively. If you could provide examples, resources, or best practices for checking ETABS models and dealing with common error messages, it would be immensely helpful.

Your expertise and advice would be greatly appreciated, as I'm eager to enhance my proficiency in working with ETABS.

Thank you in advance for your assistance.

Sincerely,
ENG.Ghazwan Asaad PE,PMP

 

[JoshPlumSE]

Whatever file you were trying to attach didn't seem to work correctly.

It would help if we knew what type of model you were having trouble with. My preference when learning a new program is to start with relatively simple 2D models. Continuous beams, trusses, 2D moment frames.

Obviously, it's not always possible to do this in engineering practice. But, even for a complex 3D structure, I might start with a single 2D frame. Add some simple loads to it to make sure it's working properly, then expand the model out a bit.

Generally, I keep my analysis simple at first. I don't use anything non-linear (even P-Delta) until I'm comfortable that the model is working correctly. Then I add complexity.

 

[Luceid]

Of course plotting deflected shape under dead load, modal cases and running the animation can identify spots that are unstable. In addition - for more difficult instabilities that you aren't able to trace or are stopping the program from running - you can try switching to the standard solver which will show unstable nodes in the analysis log. Instability errors are what I usually run into - so that's about all I can help with

 

[Celt83]

Good working knowledge in Matrix Structural Analysis, direct stiffness method, goes a long way in reducing the number of modeling errors, I tend to recommend Matrix Analysis of Structures by Kassimali mostly because it is very easy to follow and shows the element derivations via standard mechanics and then through virtual work. The 2nd and 3rd editions also contain a chapter at the end on non-linear analysis.