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Designing Hooked Anchor Rods 2

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I'm new to structural engineering and I need to design hooked anchor rods for a structure. What are the equations used to find hook length and embedment length? What publication (aisc, aci?) provides a guide for doing this? Like I said, I'm new to this so any advice would be greatly appreciated. Thanks,

ER
 
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If your anchor rods are subject to any tension at all, DO NOT used hooked anchor rods. The are subject to straightening and pulling out of the concrete. Use a straight rod with a nut welded to the end.
 
prconsultant-
The second edition cautions against using hooked anchor rods subject to tension for the reasons stated above. If it is not subject to tension, then any nominal hook will do.
 
Just need to add an important exception to your suggestion StructuralEIT. If you choose to tack weld a nut to the end of the rod, you cannot use a high strength rod due to its brittleness. This is why I always suggest just using a jamb nut.
 
Note that ACI-318 does in fact give an equation for pull-out of hooked bolts. It is much lower than that a headed bolt, and if the body of the bolt is stressed to any great extent, you'll need the headed bolt for proper anchorage.
 
Just to add a bit of variety to your discussion, it is common in Australia to use U-bolts, thus making the tension continuous around the bends and avoiding the straightening problem. Also common is the use of deformed reinforcing bars, threaded at the top. Capacity of these is based on the reduced area at the threads, and considers the tensile strength of the inner part of the bar, which is not as strong as the outside.
 
hokie66... and for larger loads, using Dywidag threadbar... nuts are expensive, but you can get high strength materials, if you really have a tensile load and you can treat the embedment like a conventional reinforcing bar.

Dik
 
You may also use the PCI Design Handbook, 6th edition. Hooked rods are not recommended but can be used if properly designed. In some cases you may get better results with the PCI than the ACI.
 
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