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RE: lateral load to Dave Anderson

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Christopher-

The 33rd Edition of ASTM, 1996, volume 1 has three (3) grades for A307 
bolts.  Dave Anderson's original question related to tilt-up wall anchors. 
 In my experience, these are usually non-headed anchor bolts, either 
straight or bent.  The description of Grade C is "Nonheaded anchor bolts, 
either bent or straight, having properties conforming to Specification A 36 
(tensile strength of 58 to 80 ksi (400 to 550 Mpa)) and intended for 
structural anchorage purposes."   The ASTM A-36 specification has limits on 
Carbon (.26%), Phosphorus (.04%), Sulfur (.05%), Silicon (0.40%) and copper 
(when specified, 0.20% min.) for 3/4" diameter and smaller and 
Carbon(0.27%), Manganese (0.60-0.90%) with the same limits for the other 
elements for 3/4" to 1-1/2" diameter.  It further specifies elongation 
minimums (20% in 8 in., 23% in 2 in), minimum tensile strength (58-80 ksi) 
and minimum yield point (36 ksi).  Maybe time to update your 1974 ASTM 
Specifications re: structural steels?  Then again, from what it sounds like 
you work with, the quality of the steel in those applications has a history 
of being much closer and carefully controlled so you probably get a chuckle 
out of what we structural folks have accepted over the years.  :<)

The one thing that may have been missing in Dave's specification is clearly 
specifying Grade C.

Bill Cain, SE
Oakland, CA


-----Original Message-----
From:	Christopher Wright [SMTP:chrisw(--nospam--at)skypoint.com]
Sent:	Sunday, November 22, 1998 19:46 PM
To:	SEAOC Newsletter
Subject:	Re: lateral load to Dave Anderson

>If you check the ASTM Specification (upon which the AISC stated values are
>based)
I have an old copy (1974) of A307. There are two grades A & B both of
which require 18% min elongation in 2 inches. The only chemistry is a max
for sulfur and phosphorus, all higher than the 0.05/0.04 pct max for
A-36. Also unlike A-36 there is no specified yield strength, although
that doesn't mean there is no yield point. It probably varies so much,
given the non-descript chemistry, that it varies too much to prove
anything.

>Last time I checked it was one of
>the more ductile structural steels available.
You don't want to confuse toughness and pct elongation. A-36 and A-307
have a high transition temperature and aren't the most impact resistant
materials ever to come down the pike, although the elongation is fairly
high.

Christopher Wright P.E.    |"They couldn't hit an elephant from
chrisw(--nospam--at)skypoint.com        | this distance"   (last words of Gen.
___________________________| John Sedgwick, Spotsylvania 1864)
http://www.skypoint.com/~chrisw