Calculating Deflections of I-Beams with Varying Loads and Supports

[PTW]

My objective is to be able to calculate only vertical deflection of I-Beams (i.e. knowing which formula to use).

Constants:
Using a pair of I-Beams running parallel to each other with a single load being applied from directly above. The load sits on a steel plate across both Beams that are 4" apart. The Beams are pinned at each end with the single load centered half way (i.e. 12' beams with load applied at 6').
Variables:
The only two shapes of beams being used are S, and occasionally W. The most popular models being S10x35, S15x50, S18x70, and possibly a W12x40.
Beams will have a minimum rating of 50ksi (A992 or A572)
Beam lengths can vary from 8' long to 20'
Total loads vary from 120k to 260k (for the two beams to carry).

Thank you!

 

[jrmichler]

Get a copy of Steel Construction Manual, by AISC. You need a solid background in strength of materials in order to understand it.

For the loading you show, you need to check for web buckling and shear in addition to bending. There is no one single simple formula. You need to do it right, or find somebody who knows how to do it right.

And do not stand near that setup when testing. If something let's loose, bad things can happen very fast.

 

[berkeman]

Thread closed temporarily for Moderation...

EDIT -- Thread re-opened after a Mentor discussion about safety issues.

@PTW -- your Profile page shows that you have a BSME and are working on your MSME. Can you say what courses you have taken that should help you to make this kind of calculation? Thanks.

Location:
SW US
Occupation:
Field Engineering
University:
Mizzou
Education in Progress:
Masters
Completed Educational Background:
Undergrad
Favorite Area of Science:
Mechanical Engineering, Telecom

 

[Dale]

You may want to look at this summary too.

http://ruina.mae.cornell.edu/Courses/ME4735-2012/Rand4770Vibrations/BeamFormulas.pdf

 

[PTW]

You may want to look at this summary too.

http://ruina.mae.cornell.edu/Courses/ME4735-2012/Rand4770Vibrations/BeamFormulas.pdf

Thank you, Dale.

 

[Dr.D]

@PTW If you have completed a BSME as Berkeman indicates, surely you took a mechanics of materials course (not to mention a machine design course) in which you would have learned how to calculate the deflections of a uniform beam on simple supports. Is there something unusual about this case?