Return to index: [Subject] [Thread] [Date] [Author]

Re: Steel Reinforcement Elongation Limit

[Subject Prev][Subject Next][Thread Prev][Thread Next]
As well, I believe the intent of the ACI code is that the development
length provided in the code would fully develop the bar.  This would mean
that the bar would reach yield stregth and "plateau" while elongating.
That is to say that no matter the elongation, the "bond" between the steel
and concrete would never "break" allowing the bar to pull loose.  Thus,
the bar would either fracture or the concrete would crush before the bar
would pull loose.  This is all predicated on proper developement of the
bar.

I could be wrong, so maybe someone more knowledgeable will chime in...

Scott Maxwell, PE, SE


On Tue, 25 Jul 2000, Roger Turk wrote:

> ASTM requires 11 to 12 percent (min.) for Grade 40 steel, and 7 to 9 percent 
> for Grade 60 steel.
> 
> Since this is much beyond the cracking strain of concrete, the concrete will 
> crack and go along for the ride.  (Take a piece of paper and cut one edge in 
> parallel strips and glue a rubber band across the strips.  Pull the rubber 
> band and see if the glue comes loose.)
> 
> At these strains, deflected shape becomes a part in determining the capacity 
> of the structure with the structure behaving like a cable supported structure 
> more than a flexural member.
> 
> We (at least *I* do) want our structures to look like a sway-backed mule 
> before it collapses.  I do not want strains limited so that collapse comes 
> suddenly and without warning.!
> 
> A. Roger Turk, P.E.(Structural)
> Tucson, Arizona
> 
> Jim Korff wrote:
> 
> >>The steel reinforcement "yield point" is at an elongation of .002  (0.2%)
> 
> Does ACI Code give a maximum permitted elongation for internal reinforcement
> ??
> 
> (For DIN it is 0.5% and for the Euro Standard it is 1.0% )
> 
> Are there any papers or research on this subject -maximum elongation to
> avoid steel/concrete bond failure ??<<
> 
> ******* ****** ******* ******** ******* ******* ******* *** 
> *   Read list FAQ at: http://www.seaint.org/list_FAQ.asp 
> *   This email was sent to you via Structural Engineers 
> *   Association of Southern California (SEAOSC) server. To 
> *   subscribe (no fee) to the list, send email to 
> *   admin(--nospam--at)seaint.org and in the body of the message type 
> *   "join seaint" (no quotes). To Unsubscribe, send email 
> *   to admin(--nospam--at)seaint.org and in the body of the message 
> *   type "leave seaint" (no quotes). For questions, send 
> *   email to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
> *   send to the list is public domain and may be re-posted 
> *   without your permission. Make sure you visit our web 
> *   site at: http://www.seaint.org 
> ******* ****** ****** ****** ******* ****** ****** ********
> 


******* ****** ******* ******** ******* ******* ******* *** 
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) to the list, send email to 
*   admin(--nospam--at)seaint.org and in the body of the message type 
*   "join seaint" (no quotes). To Unsubscribe, send email 
*   to admin(--nospam--at)seaint.org and in the body of the message 
*   type "leave seaint" (no quotes). For questions, send 
*   email to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********