error "compressive stress in tendons"

[Anonymous]

Hello!

I have an issue about the posttensioned section analysis.

I defined the section, added tendons and reinforcements as shown. I am using Australian code -2017.

When I start to analyse the section to see the moment capacity, it keeps to give error "compressive stress in tendons". I need to press "ok" button literally a million times :(.

I tried to erase all reinforcement, it analized easily. I could not figure it out what is the problem.

Thanks for your help!

Yasam

[dave_geeves]

Hi Yasam,

Apologies for not providing a response sooner.

The software will not allow any of the defined tendons to have a compressive strain which means that the tendons in the top of your section, at ULS, must have compressive strains due to the ULS external moment greater than the tensile strains due to the internal prestress.  It is difficult for me to comment further until I see what is in your data file.  Could you please zip up your data file and attach it to a reply to this post and I will investigate further.

Kind regards

Dave Geeves

[Anonymous]

Hi Dave,

Thank you for your response.

Before I post the question, I tried to analyse by reducing the ULS Moments, even I tried to delete all the load cases completely, nothing changed. However, yesterday it did the analysis without any error, although I change nothing 🙂 So, the problem is solved now.

Thanks again,

Regards,

Yasam

[dave_geeves]

Hi Yasam,

That's good news that the problem is now solved.  You should note however that if you set the loadcase in the analysis form to a particular case with just Mx moments  and also set the required resistance to Mx then  the solution will always be the same as the program applies any moments etc from the loadcase and then establishes what additional moment can be carried up to ULS.  If however you set the resistance to *Not Used* than the  program just applies the moment from the loadcase and balances the internal forces to give a solution for that load case,  I suspect that this is what is happening here.

I hope this helps

Kind regards

Dave Geeves