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Typical Anchor Bolt Projection

Typical Anchor Bolt Projection

Typical Anchor Bolt Projection

I am working on a project where anchor bolt projection is a critical dimension. These are on grade bus stop platforms, where the custom designed shelter (designed by me, not an off the shelf shelter) will be anchored to a mat footing on grade, after which a topping slab containing a snow melt system will be placed over the mat footing.

I have instructed the design team we need a 6" topping slab, based on 4" anchor bolt projection at the shelter column base plates, and 2" cover over the anchor bolt tip. I believe 4" is a typical anchor bolt projection, but have been unable to find confirmation online. I plan to use 1-1/2" grout, and estimate the base plate will be no more than 1" thick (haven't designed them yet).

Is 4" a reasonable dimension for anchor bolt projection?


RE: Typical Anchor Bolt Projection

See no reason why that wouldn't work. 1 1/2" of threads above the baseplate. You could reduce 1/2" if you wanted but give a little less margin for install error.

RE: Typical Anchor Bolt Projection

This is copy and paste from PIP STE05121 Anchor Bolt Design Guide ;

( Anchor bolts should project a minimum of two threads above the fully engaged nut(s).)

Typical for Single Nuts , Projection = grout thick + base plate thick.+ 2.0 X anchor bolt dia.

RE: Typical Anchor Bolt Projection

As HTURKAK noted, it will depend on the height of the nut, which is a function of the anchor bolt diameter and the type of nut(s).

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RE: Typical Anchor Bolt Projection

A couple of cautions... make sure your anchorrods are weldable and check to see that your grout can be used to 1-1/2" thickness... 1-1/2" grout seems a little thick.

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RE: Typical Anchor Bolt Projection

I'd say that 4" is perfect as a minimum for 3/4" bolt and washer with 1/2" vertical placement tolerance.

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