Beam - Unsupported beam compression flange

[bjmatthews]

If you have a W12x16 beam supported on top plated columns at each end and the beam is 50'-0" lg., will the beam fail in bending if the only load on the beam is the weight of the beam itself? Assume there is no axial or lateral loads applied on the beam and that the unbraced length is the full 50'-0" length.

bjm

 

[burtonli]

In this case, you must calculate the bend moment cause by self weight. You can calcalate Fb according to AISC F.3. In the other hand, we also control l/r<=200.

 

[JAE]

For a W12x16, with A36 steel - self weight only and 50 foot span I get the following unity values:

1.81 LRFD
1.98 ASD
Deflection at midspan = 0.75 inches
...fails miserably.