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Steel Connection Design using Etabs


Juli
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Hello.. Is it possible to analysis and design a steel building fully with Etabs including purlin, rafter assigning? And also for connection design and baseplate, is ETABS connection menu is well enough or ok for modification and using practically? Or you experts are using any other soft for only steel connection design from etabs output? I mean I have tried TEKLA, but it seems to me only good for steel detailing, again in staadpro, there is RAM connection but I don't prefer staad pro for modeling complex and tall structures as the visual and graphics effect and also complex lengthy terms. But my seniors told me that staad pro is used and better for steel structures, for connection design etc, but I do prefer ETABS, I see there is connection design tab and procedures, but as I am new in steel learning, so can I do all things, connection, baseplate design, modify I mean as per AISC code everything change that I need in etabs for steel?  Please suggest.Thanks in advance.

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Juli,

For steel, I do the software analysis and member sizing of the members using SAP2000 or RISA3D. For baseplate design, I either do manual calculations or use an in-house software.

For connection design, I show the connection loads on the design drawings and provide them to a fabricator. The fabricator's engineer designs the connections, stamps his drawings and submits the shop drawings to me for review before they are issued for construction. This is the standard practice in North America.

Thanks.

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Thanks a lot. So now can you please tell me in short if you don't mind please, that the using of SAP why better or you prefer for steel analysis and member sizing  than ETABS? What privileges I will get better in SAP than ETABS for steel? And also, so for connection design or baseplate, Can I do that from connection loads or forces output from SAP and in RAM connection if you know, as I will have to learn that and I am not in touch with any fabricator ? Thanks again for hanging out with me and providing informative information, I am really grateful :) 

 

And please help with these issues I posted another thread and now deleting and so posting here :

1. Hello.. can you please explain simply that when I will assign pinned support and when fixed in ETABS? Please do not mention huge geotechnical issues here as they just sometime make it much more complex, you please explain it simply with soil condition basing or footing based. 

2. Does etabs automatic count for long columns, i mean if a column is slender column, will etabs will design it considering slender column design process and length factors? or will I have to do it manually and if so, how? 

3. If I assign fixed support, then what would be for baseplate design consideration? biaxial moment should be considered or fixed isn't ok for baseplate? 

4. When exporting slab from etabs to safe, will i need to export lateral load combos also for moment consideration? Same for footing in Safe, I am exporting etabs base reactions for footing design in Safe (isolated or combined), now will i need the al load combos like for horizontal forces or moments also? Or just like only gravity  load combination reactions need to be exported? 

5. It's ok that when I do P delta effect assigned, that means when I am doing 2nd order analysis in Etabs, then I am using section modifier value for frames and slabs ( Like as ACI directs .7 for column, .35 for Beam, .25 fo shell etc. ), But if I don't perform 2nd order analysis, i,e  P delta analysis, then do I need to change the default modifiers ( that are 1 ),  or if I do change, then is it wrong? 

Thanks 

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6 hours ago, Juli said:

So now can you please tell me in short if you don't mind please, that the using of SAP why better or you prefer for steel analysis and member sizing  than ETABS? What privileges I will get better in SAP than ETABS for steel?

The company I work for has license for SAP2000 and RISA3D only. They don't use ETABS and thats why I don't use ETABS either. I have found RISA3D more friendly for connection output.

6 hours ago, Juli said:

And also, so for connection design or baseplate, Can I do that from connection loads or forces output from SAP and in RAM connection if you know, as I will have to learn that and I am not in touch with any fabricator ?

You should be able to do it. I haven't used RAM connection but you should be able to get output from SAP2000 and use that in RAM Connection. The softwares (SAP2000 and RAM Connection) I believe are not integrated and you would have to manually enter data in RAM Connection. I did some google and noticed that Ram Connection is integrated with Staad Pro. You can check the following website for more details: 

http://communities.bentley.com/products/structural/structural_analysis___design/w/structural_analysis_and_design__wiki/8354.tips-for-using-ram-connection-within-staad-pro-tn

6 hours ago, Juli said:

1. Hello.. can you please explain simply that when I will assign pinned support and when fixed in ETABS? Please do not mention huge geotechnical issues here as they just sometime make it much more complex, you please explain it simply with soil condition basing or footing based. 

Pin or Fixed from a geotechnical perspective: http://www.sepakistan.com/topic/1578-pin-support-or-fixed-support/

Pin or Fixed from Column Base Plate Connection perspective: http://www.sepakistan.com/topic/1500-steel-column-base-plate-modelling-in-sap/

7 hours ago, Juli said:

2. Does etabs automatic count for long columns, i mean if a column is slender column, will etabs will design it considering slender column design process and length factors? or will I have to do it manually and if so, how? 

I am not very familiar with ETABS. I would let someone else answer this.

7 hours ago, Juli said:

3. If I assign fixed support, then what would be for baseplate design consideration? biaxial moment should be considered or fixed isn't ok for baseplate?

A fix support assignment for connection between your column and baseplate would induce moment in your baseplate. You need to design your baseplate for the reaction moment along with other loads.

7 hours ago, Juli said:

4. When exporting slab from etabs to safe, will i need to export lateral load combos also for moment consideration? Same for footing in Safe, I am exporting etabs base reactions for footing design in Safe (isolated or combined), now will i need the al load combos like for horizontal forces or moments also? Or just like only gravity  load combination reactions need to be exported?

You should export all load combinations for strength design of foundation. Please note that some load combinations might not be applicable for bearing pressure check depending upon the code you follow but they are applicable for foundation design (flexural and shear design of foundation).

7 hours ago, Juli said:

5. It's ok that when I do P delta effect assigned, that means when I am doing 2nd order analysis in Etabs, then I am using section modifier value for frames and slabs ( Like as ACI directs .7 for column, .35 for Beam, .25 fo shell etc. ), But if I don't perform 2nd order analysis, i,e  P delta analysis, then do I need to change the default modifiers ( that are 1 ),  or if I do change, then is it wrong?

You should consider stiffness modifiers irrespective or p-detals.

Thanks.

 

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