Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: hole in steel web

[Subject Prev][Subject Next][Thread Prev][Thread Next]

It is entirely dependent on a number of factors...where in the span of the
beam (ie middle or at the end near the connection); where in the depth of
the beam (ie close to a flange or near the center); loading on the beam
(ie is it a beam [uniform load] or a girder [point loads] and if it is a
girder, then how many beams frame into it); new or existing beam; how will
hole be installed (drilled is not too likely with a 3 1/2" diameter
hole...more likely flame cut/plasma cut); and size of the hole (which you

For example, if the hole were to be placed in a beam (uniform load) within
the center third of the beam and at the mid-height of the cross section,
then it more than likely would not be a problem.  In that type of a case,
the hole could likely be installed without reinforcing the web.

However, if the hole were to be placed near the end of the beam (at a
location with high shear) in a beam with a highly loaded relative to its
shear capacity, then it could either be done with the web reinforced or
installing the hole may not be possible in that case.

For further information, there is a Design Guide for web openings that
AISC publishes.  More information is available at:

Also, AISC has a computer program that is the "companion" to the Design
Guide.  More info at:

Hope that helps some.


On Thu, 5 Oct 2000, Francisco Duarte wrote:

> Does anyone have any info. concerning drilling a hole in a steel web.
> I have a W18X50 and the contractor wants to drill a hole 31/2 inches in
> diameter in tithe web.
> What should I be concert in this situation. Any info will be greatly
> appreciated.
> million thanks,
> F. Duarte, EIT.