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Anchorage to concrete

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Can anyone lead me to a source to prove that a hooked anchor bolt (j-bolt)
can develop the loads typically used for hold downs when cast into a stem

Using section 1925.3.2 ('94 UBC) with a phi factor of .85 (assuming the
j-bolt is hooks around a horizontal bar) and an edge distance of 2.75 inches
(assuming an 8 inch stem wall but the bolt is centered in a 5-1/2 inch 2x6
plate), what should the value be for As?

If I use concervatively a truncated cone with a diameter of 5.5 inches and
an embedment length of 2.75" so as not to have to reduce for lack of edge
distance, I come up with a tension value of 4045# for 2500 psi concrete.
For service load design, this would need to be reduced by a load factor of
1.3 for wind and 2.0 for no special inspection which results in a value of
1555#.  This does not develop the load for even an HD2A bolted to a double

I assume it is acceptable to use more surface area then this conservative
assumption but the question is how much and how is it justified?

Thanks in advance for any input.

Randy Hamilton P.E.
Tucson, AZ