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anchor bolts: a36 or a307?
aisc 9th, says a307 has a higher tensile strength, as well as higher allowable tensile and shear loads as compared to a36. i can find neither a yield strength, nor an ultimate value for a307. why?
other than the slight difference in values, what advantage does one have over the other?
thank you ...
i thought a307 is the bolt designation for a36 steel. a36 is for structural shapes.
check pp 4-4, table 1-c - it lists a36 for threaded round stock. i believe a307 is for bolts and studs only, not all thread.
i agree with cvg: a36 is all thread and a 307 is headed (bolt). i had a steel fabricator rub my nose in this distinction a few years ago and will not forget which is which.
the astm callouts for all thread anchor bolt type stock should be f1554, gr. 36 or a36.
a307 has no specified yield strength, only tensile strength. the tensile strength for a307 is slightly higher than that for a36. you may find these strengths in the connections chapter of the aisc 9th.
i was thinking that one of the grades of a307 (grade c, if i re
i recommend you look into astm f1554 anchor rods. this is the most up to date spec on anchor rods of which i am aware. these come in three strengths: 36ksi, 55ksi and 105ksi. good luck.
a307- grade a has minimum tensile strength of 60ksi.
a307- grade b has tensile strength of 60ksi-100ksi.
a307-grade c has "properties conforming to" astm a36- tensile strength of 58-80 ksi.
yield is not listed for grades a and b. there are hardness requirements for grades a and b, as well as specified tensile requirements for each bolt size.
i just got off the phone with birmingham fastener, inc. which is one of the major structural headed bolt and threaded rod manufacturers of only a few in the nation that most of the nations fabricators will puchase anchor bolts from. i know this because i used to be an estimator at a local steel fabricator that used to purchase anchors from nashville bolt which is no longer in businesss, and now this fabricator uses birmingham.
apparently, as jstephen stated, most of the a307 bolts and threaded rod is made from a36 steel. a307 gr c, is a recommended specification that simply involves less certificationary paperwork that involves certain testing procedures which, unless required or specified by the engineer, can be avoided, thus costing less and producing virtually the same a307 material specification. does anyone know anything more, either supporting, or contrary to this alleged claim by birmingham fastener?
apparently, a36 and a307 are available in either threaded rod or headed bolts. aisc is not always accurate or current considering the 9th ed. is over 15 years old...
we need to check with your local fabricator and national manufacturers to insure that our specifications and intentions compliment what is actually available and what the local fabricator is willing to work with, providing there is room for flexibility.
jstephen,
where did you get your info from? i can't find it in aisc 9th ed.
astm's website, astm.org, has the info provided by jstephen above. just do a search on a307. the spec is titled "standard specification for cs bolts & studs 60,000 psi tensile strength. in addition to what jstephen has listed, grade a is for general applications, grade b is for flanged joints in piping and grade c is for non-headed anchors |
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