Drilling 2" hole through steel beam...

[jimtheengineer10]

There are 4 existing steel beams supporting the roof of a structure. The beams are 42" x 3/8" web with four L's that are 6"x6"x5/8". The beams are 60' long clear span. The client is wondering if he can drill 2" holes through the beam to install a stormwater drain. There would be 5 holes drilled in the beam approximately equal spaced along the 60'. Can someone steer me in the right direction to where I can begin to determine if a 2" hole can be drilled through the beam and if it needs to be reinforced. Thank you.

 

[JAE]

AISC has a design guide for web openings in beams.

AISC Design Guide 2

 

[BAretired]

The usual rule is that any holes should be in the middle third of the web. Two inch diameter holes should be no problem.

BA

 

[dik]

Use a hole 'drill' rather than a bit... they cut through faster than a regular drill and use a mag drill...

Dik

 

[hokie66]

No problem with the holes, but you would have to wonder about how much good a 2" hole does for stormwater.

 

[BAretired]

I don't suppose a four inch hole would be a problem either.


BA

 

[dik]

Not with a hole drill...

Dik

 

[JAE]

Unless it is a W4 beam.

 

[jimtheengineer10]

Thanks for the replies. The stormwater text was a typo, it is a drain line for a sprinkler system.

So as long as the holes are in the middle third of the beam he should be all set right