Beam on top Of Col. Moment Connx. 1

[palk7 EIT]

Hi,

When having a beam on top of col. for moment connx. While sizing the cap plate thickness of the column at top how to resolve that moment in order to find the thickness of that plate? Attached the image for reference.
Thank you! and appreciate your inputs

 

[BAretired]

Forget about using four stiffener plates. Size the cap plate to take all of the moment from two bolts.
Bolt tension = 2.35*12/7 = 4.0 kips for two bolts or 2 kips per bolt. (bolt spacing 7")
Mplate = 4*1.5" = 6 k" (eccentricity 1.5")

You should have a stiffener in the beam too. A split HSS 4x4x1/4 is my preference, but you could probably get away with less.

BA

 

[dik]

as BART notes... but for a beam stiffener, I'd likely use a BAR 3/8 x 2.5 on each side... cut back 1" from the top flange. Loads are small... just a hint. If you ever try to analyse stiffener plates into the face of an HSS, you are in for a real treat... it's cheaper to eliminate them, even if top plate gets thicker.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[XR250]

2.35 ft-k ain't much. Might not need a stiffener in the beam

 

[BAretired]

2.35 ft-k ain't much. Might not need a stiffener in the beam

The stiffener is needed in the beam, even if the moment is zero. I agree with dik that a split HSS is maybe overdoing it a bit, but what the hell, you are using an HSS under the beam, so who cares? And it need not be full height. 3/4 height should do.

BA

 

[canwesteng]

The stiffener is the beam is required for rotational stability at the end if no other method of grabbing the top flange laterally is provided. I'd be surprised if the flanges need reinforcing for 2.3 k-ft, but there is a simple check in the AISC spec for that.

 

[BAretired]

Who cares? It is simply good practice to put a stiffener in the beam over a support. Just do it!

BA