U-frame Analysis necessary even after designing everything in STAAD?

I did not see any issues with the model. The only thing that is missing is a LOAD LIST command before both the strength and the serviceability checks just to ensure that strength check is done for the combination 7 and serviceability check is done for load combination 6. Modified file is attached.

I am not too familiar with the standards you mentioned and so cannot comment on whether a U Frame analysis is mandatory or not. However my personal take on this is, a properly substantiated 3D analysis is much more accurate than any manual analysis.

Teignmouth_rev.std 

I did not see any issues with the model. The only thing that is missing is a LOAD LIST command before both the strength and the serviceability checks just to ensure that strength check is done for the combination 7 and serviceability check is done for load combination 6. Modified file is attached.

I am not too familiar with the standards you mentioned and so cannot comment on whether a U Frame analysis is mandatory or not. However my personal take on this is, a properly substantiated 3D analysis is much more accurate than any manual analysis.

Teignmouth_rev.std 

Sye,

Thank you for the suggestion and help.
Also if you notice the model for the vertical members of parapet I have used "user table " sections. I had tough time calculating section properties for these vertical members. these are "back to back T sections" which is not possible to add as standard sections in STAAD. Hence I did create a user table. for Warping constant Cw , since I didn't know formulae hence I used nearest Standard T section's Warping constant and doubled it up.
Do you know any other software or book or any reference to calculate section properties of unconventional builtup sections.

Thanks
Mahesh

Generally for calculating properties for built up sections or non standard sections, you can use Section Wizard which is also integrated with STAAD.Pro. These sections can be formed using a combination of standard sections and plates and Section Wizard would be able to calculate the properties for you and also export it to an external user table file which can be imported into STAAD.Pro.

As far as Cw calculation is concerned, design codes like AISC 360-05 or 10 provides values in the property tables but these are for standard shapes. AISC design guide 9, engineering text books like Formulas For Stress and Strain by Raymond J. Roark are some other documents that I can think of, which has some information on the Cw. I am not aware of tools that can be used for non standard shapes.

Hi sye,

Thanks a lot. Your advice of using Section wizard has worked for me. I referred your other article to learn Section wizard. I am sorry for bugging you again but there seems to be new issue here now.

I used section wizard to create "double T -back to back". It successfully creates all the properties even Cw (which is HSS). But I noticed it dint give me values of Shear area Ay & Az!!. Should I understand as " this section has no shear area?! which is not possible. OR wizard cant interpret Shear area formulae in this case?

I have uploaded the screenshot of section for your reference and also  I couldn't upload the .upt file as this wont allow me.

Thanks again

Mahesh

Also,
It doesn't show properties such as Ix, HSS when imported into the STAAD as User Table! but in section wizard it shows. I am quite confused over this.

In Section Wizard, the user can assemble any section of his/her choice or draw any shape. Calculating the properties like shear areas and terms like TB, TD etc. for such shapes can be quite tricky and while the software tries to come up with a reasonable estimate for these terms, the user should always check these terms before exporting the section and also make changes if required. Recent versions of the product, mention this as a warning at the bottom of the export dialog box as shown in the screenshot below.

In this case the zero values reported for Ay and Az mean that the software is not able to come up with a value for these terms. So you should go ahead and specify these yourself. If the export is already done, you can always directly open the upt file and edit the appropriate values. Section 5.19.8 of the technical reference manual lists the order in which the terms are defined in the upt for a general type section.