Composite and non composite

[johny13]

how do we verify that girder is composite or noncomposite. should we calculate total no. of sher studs per row? can anyone explain it. i need it for load rating purose.
Thanks

 

[BridgeEI]

In design, you would calculate the number required for the strength condition between tenth points or between inflection points and then make sure you have that or more.

I would run the calcs to make sure there are enough studs so that you can rely on composite action. But you would also need to make sure you meet pitch/transverse spacing requirements as well.

 

[johny13]

thanks for reply.
how much minimum studs' spacing required to consider as composite. my girder length is 84ft and from framing plan studs are 3 per row@12"-Can i consider this girder as composite. its WPG, SS.

thanks again

 

[BridgeEI]

You need to run the numbers. Take a HL93 design truck and find your max shear at each tenth point. Once you do that, determine the horizontal shear at each tenth point and compare that to the capacity of your studs. I can't remember all the variables required, but look through the aashto code and see what is needed.

 

[bridgebuster]

luharr - if you have 3 studs at 12" I think it's safe to assume you have a composite section.

BTW - no offense - you're questions about ratings are making me nervous.