Steel to concrete connection
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What is the best way to connect a steel beam to concrete pier?
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This is often done be setting threaded anchors into the concrete at the time of placement, then bolting the steel in place. The easiest way to install anchors after the fact is to set them in the concrete with epoxy. For lower loads, a whole range of expanding anchors are available. Then there are Tapcon screws and powder actuated fasteners as well. It all depends on the application, loads, environment, etc. If this is a structural application, this connection should be designed by an engineer, who should take all of these issues into account in the design.
Thanks Peter. I appreciate your response!
Don’t use powder actuated fasteners for a connection like this, they are not reliable. Tapcons aren’t the best either in this application. Epoxy anchors are excellent, but their proper installation is ABSOLUTELY CRITICAL if they are going to be safe. Expanding wedge type anchors (like redheads) are good. Best is a proper L bolt embedded in the concrete during the pour.
When I design connections like this, I spec embedded bolts in the concrete (make sure your contractor has them fastened to a template while the concrete cures. Don’t count on them to do this and not just stick them in a “pretty good spot that’s close”. Ask me how I know....). Use the correct bolts and nuts (typically A325), not hardware store stuff.
The bolt will have a minimum required embedment in the concrete that will depend on the application, and it may also need to tie into a rerod cage within the concrete footing. This will all depend on the forces expected to be exerted on the connection.
The bottom of the column will usually have a flat plate welded to the bottom with a perimeter weld, the plate then gets bolted to the concrete. If designed correctly, you can use nuts both under and on top of that plate to allow for leveling (steel traffic light poles are usually set this way).
Note that you can have HUUUGE forces at work on connections like this so you should really have them engineered, or at least reviewed by an engineer prior to project start. Any structural engineer will be able to do this for you.
Bill