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Pull-Out Rating for Concrete Achor Bolts

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AbelGus

Industrial
Jan 12, 2005
29
I am looking for the pull out rating on a 1/2" anchor bolt in a concrete slab. The anchor bolts are conventional J-bolts with 4" or greater embedment in 2000 psi concrete.
 
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HILTI have a design package called Profis which I believe can be downloaded (written for their own bolts obviously). They do have resin anchor bolts in their range which may give you a feel for what you are looking at.

Rule of thumb is 1 tonne per inch embedment, but that is nothing to design on, just a pointer.
 
I never have seen concrete anchor bolts. We always use steel with standard coarse threads but I guess if you hang around long enough you'll see most anything. I recommend ASTM F1554 anchor rods.

2000 psi concrete is trash. If you can't get at least 4000 psi you need to fire your whole QC department.

4" embedment is not going to be much. I woulf neglect the effects of the hook and analyze this as a rebar embedment problem. Remember to use the reduced area on the threaded section of the bolt as the cross sectional area.

Good Luck
 
ACI 318-05 addresses this question in section D.5.3 for a J-bolt. The pullout strength of a single anchor is in section D.5.3.1 with the formula for a j-bolt in section D.5.3.5. You will see that the pullout strength for a J-bolt is much less than a headed bolt (D.5.3.4)
 
ACI 318 1.1.1 states that structural concrete must have a specified strength of at least 2500 psi. I would not anchor to a 2000 psi slab.
 
Thanks for the info (and the humor). The 2000 psi concrete comes from the literature of both Simpson Strong Tie and USP Connectors. I belive they are stating how well their post anchors work in minimal conditons (i.e. 4" of embedment in 2000 psi concrete). Never mind all of that, I decided to go with USP high uplift post anchors. For an increase from $20 to $26 per post, the uplift rating increased from 470 lbs. to 2380 lbs. and the bearing more than doubled - not to mention that they are more user friendly to install.

The problem with the hook anchor bolt is that they are ubiquitous. Substituting hardware store grade fully threaded rod is no solution because the material is low grade, and straight anchor bolts of various lengths, threaded 3 inches on each end do not appear in any supply houses that I contacted in New York state.
 
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