Structural Tee for mono rail beam

[tkordick]

I recently picked up some structural tee from a demolition site and am wanting to use this for an overhead beam in my home shop that will span about 12 feet and carry up to 2000 lb.
Using properties from my AISC book, I calculated the allowable load on the beam to be acceptable for my intent but all of the pictures I have seen show the flange on top. I want to locate the flange on the bottom to allow a trolley to ride on it - similiar to a typical wide flange beam.

Is this acceptable? Is the allowable load basically the same or will it be reduced with the flange on the bottom - flange will be in compression instead of tension.

Thanks in advance.
Tom

 

[Taro]

Flexural strength of tees is typically reduced when the stem is in compression due to lateral buckling. The AISC LRFD specification (available for free download from

http://www.aisc.org)

gives provisions for bending of tees with stems in compression or tension.

 

[StephenEd]

Things to keep in mind:

The capacity of the tee will be a small fraction of the capacity of wide flange beam from which it was cut.

The section moduli for tension and compression in a tee are very different from one another! Be careful which one you are using when checking the lateral buckling of that (compression) stem. The flange will be in tension not compression.

Tees are inefficient shapes for flexure.