STAAD API tubular design

[mhola]

Hi all. Thanks for the all the good work and support!

Question on STAAD.

Is there any way we can get STAAD to show a detailed failure criteria for tubulars when you double-click on a tubular after analysing? At the moment, it does not even show the "design" tab like it does for non-tubular section under AISC code check.

 

[accountclosed]

You can get detailed design output for HSS members if you design them against any of the AISC codes. Unfortunately you don't get the same detailed output if you use API code.

 

[mhola]

It's a real shame as we've just started to welcome STAAD's use into the offshore oil & gas structural engineering sector. We tend to use tubulars a lot and need to design them to API codes. STAAD need to get their act together as it's really a lovely program.

Another thing is the non-output of static checks results for load combinations cases.

 

[accountclosed]

It looks like it is just an oversight that the controlling code clause and Loading Condition are not reported on the member query dialog or in the Design Results table. But I should point out that this information IS provided in the analysis output file. I'll log the item now so we can try to get that output available in the other two forms as well.

 

[mhola]

Great! Thanks. Could you also log in the query about static checks (in the output file) for load combinations? That would so so useful as well.

Cheers!

 

[accountclosed]

Actually, the Statics Check has probably been implemented that way intentionally, because the program does not actually analyze the model for the load prescribed by LOAD COMB commands. Instead it simmply combines the results in the factored proportions specified by the LOAD COMB commands. For that reason, it is not really meaningful to perform a statics check on every LOAD COMB. You only need to perform the Statics Check on all of the primary load cases. From there, if linear elasticity and superposition are valid, and if the sum of the forces is zero and the sum of the moments is zero for each primary load case, then any way you want to factor and combine them, the sum of the combined forces and the sum of the combined moments must also be zero.

The big caveat here is the part about "if linear elasticity and superposition are valid". If those aren't applicable, such as when non-linearities are present, then you really need to be using REPEAT LOAD to properly capture the analysis results. Some of the common triggers for needing to use REPEAT LOADs include: tension- or compression-only members. tension- or compression-only supports, and PDELTA analysis.

 

[mhola]

Operational and Dry Weights and their centre of gravity (CoG) are such a concern in the offshore oil & gas structural sector. These we can pick straight from our load combinations once an analysis is complete. At the moment, the way we get around it is;

1. yes by setting up a spreadsheet and copying the reactions obtained in STAAD (from the GUI) and summing them up.

2. by using REPEAT load cards

I do understand the CPU processing times involved in the algebraic summation of the load combinations but all the the other softwares we use so far i.e. SACS, easily give us a summary table in its output file of all basic and combined load cases.

The ability to the see and extract an operational and/or a dry weight and their CoGs after an analysis would be greatly eased if this were added in STAAD.

The pdf attached is an example of one I have extracted from SACS. It also give their CoG without having to calculate manually. Load cases 1-3 are basic and the rest are combined. Would be really really great to see a similar thing in STAAD.

Thanks a million.