Composite Section Analysis

[Anonymous]

Dear respected colleagues/professionals. I'm new to using this software and need urgent fix on a problem. I have modeled a composite section of an RC column (0.975m) encased in a steel tube(0.026m thk). While analysing it shows property mismatch. How do i fix this. Kindly help. Urgent. I've attached the file for your review

[simon_hooper]

I don't see the file attached. Please could you zip and attach, or contact support for resolution.

Thanks

Simon

[Anonymous]

Thanks for the response. I tried attaching but it didn't take. I'll try again attaching the zip file. In case if you still don't see the file. could you please connect with me over email. its sambhav.poddar@ch2m.com. 

[simon_hooper]

Thanks for the file.  I just ran a general stress-strain analysis, interaction surface and section property analysis and they all completed without problem.  I tested in 2017.1 and 2018.2, which version are you running?

[Anonymous]

I have also 2017 version. Why does it show error messages in mine. I'm attaching the screenshots. Did you do any changes to the properties or any as such to make it work?

[simon_hooper]

Thanks for the images.

You have to do a general stress-strain analysis as per warning rather than a limit state analysis due to the presence of steel element.  The interaction curve should actually be blocked with this type of analysis (which I think is leading to the property type mismatch error).  The interaction surface feature (which is replacement for interaction curves) added in version 2018 doesn't have this restriction.

Simon

[Anonymous]

Thank you for your reply. I'm getting the stress strain results but the results are coming same for the four different SLS cases. Also, I'm limited by the availability of the version 2017. Simply put, any way I can get section capacity for ULS cases and stress/Crack width for SLS cases for the composite action of Steel and RC. 

[simon_hooper]

I am not aware of a way to achieve this in any version of the software, and to be honest, not sure of the reasons behind blocking composite steel RC sections from ULS/SLS.

[Anonymous]

Hello Mr Simon.

Thanks for your immense help. Continuing to this thread, I have a new problem statement in which I have to design a composite column (pier) section; a steel I section embedded in concrete. Attached is an image of the section. Please guide me how to model. Many thanks. Sambhav

[simon_hooper]

Hi Sambhav

I have modelled and attached as a Design Section.  Basically you can copy the steel section (which I have modelled as a parametric shape, but could be a steel library section) and change the material property of the copied element to a void.  See images and attached file.

Simon