Anchor Bolts
Anchor Bolts
(OP)
Typically I use F1554 anchor bolts. I have a case where I need to develop the capacity of A325 bolts in a cage of steel. Is it possible to get headed anchor bolts 30" long with a capacity equal to A325's. Thanks for your help.






RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
RE: Anchor Bolts
Reason being, according to IBC 2000 Sec. 1913.2.1 Definitions, an element must have a tensile test elongation of at least 14 percent and reduction in area of at least 40 percent to meet a "Ductile Steel Element" classification. GR36 and GR105 meet these requirements however GR55 has a reduction in area of only 30%.
Therefore it is classified as a brittle element and you get hit with a phi reduction from 0.90 for ductile to 0.75 for brittle steel strength (1913.4.4). Also note that the steel strength is based on ultimate not yield stress. Allowable ultimate stress is 58 for GR36 and 75 for GR55. So going from a GR36 to a GR55 you only gain [(0.75/0.9)(75)]/58 = 1.077 = about 8% strength gain. So either 1. Use a slightly larger GR36 or 2. Jump up to GR105.
Note that in IBC 2003 which Ref. ACI-02 Appendix D the requirements for ductility have been reduced to 30% and therefore GR55 would be considered ductile and the above does not apply.
RE: Anchor Bolts