C-Channel Web Openings 1

[dreber]

I have a client who wants to put a hole through the web of my c-channel beam. I am aware of AISC Design Guide 2, but it restricts its guidance to I shaped sections.

Anybody know where I can go to for design guidance on c-channels with web openings?

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David Reber

http://www.kadent-structures.com

 

[r13]

I would just say no to the client, as there are too many complications.

 

[Retrograde]

I would have thought you could use AISC Design Guide 2, but you would need to modify some of the expressions to take into account the different shape.

I do not think the plastic shear capacity of the top or bottom tee is affected by the fact that you have an "L" shape instead of a tee. The local buckling check of the compression flange should be the same. The calculations for the buckling of the tee-shaped compression zone will need to change for your "L" shape.

 

[Agent666]

Can you put a stiffener on the other side to the flange. Turn it into a semi-symmetrical I-Section over the location of the penetration if you like? Or just swap it out for an equivalent performance I-Section if it's a new build.

SCI design guide P355 has some additional requirements when for example you have a single sided stiffener. I'd imagine some of the same limitations apply in principle for good reason. The centroid of the L shaped bottom flange has a tension force that is offset from the web so you get minor axis flexure occurring. Best to keep it symmetric to eliminate these types of issues.

 

[dik]

A666: Thanks for the link...
-a packrat


Dik