Clip Angle on Concrete

[jheydon2]

Hello,

We use the following connection for our plate settler frames inside basins for water treatment plants. My question is do I need to consider moments on the anchorage into the concrete due to the eccentricity of the connection of the beam web in relation to the anchors? Or do I just analyze the shear loads? Any references to AISC codes would be greatly appreciated!

Thanks in advance.

 

[JAE]

I would consider the eccentricity assuming there is downward load on the beam (vs. axial only). If only self-beam weight then I might ignore the eccentricity.

There will be some "grip" on the two web bolts that will sort of simulate a rigid extension of your beam, but I'm presuming there would be some slip and not a full moment stiffness in those two bolts.

Plus, it's a conservative, safe thing to do.

 

[Once20036]

The load needs to get to the face of the concrete somehow. If that bolted connection at the beam web is designed for a little bit of moment, the anchor bolts into the concrete can be designed for zero.
If that is a loose connection with horizontal slots, I`d design the anchorage into the concrete for a moment equal to the vertical load * the distance from the concrete to the two web bolts.
(I think this is the same thing JAE said)

 

[DaveAtkins]

I normally assume no moment to the concrete. I assume the two bolts between the double angles and the beam web can transfer moment, and the point of inflection of this connection is at the face of the concrete.

DaveAtkins

 

[canwesteng]

Clip angles in that configuration are very flexible, so assuming no moment is probably ok in that situation. If it were a shear tab, I would design for some moment in the concrete even though that isn't done in steel to steel, just based on having less ductility in the supporting member and the stiffness of the concrete wall being quite high.