Anchorage lengths for straight and bent bars
Anchorage lengths for straight and bent bars
(OP)
Hi,
I realized in the Eurocodes that the anchorage lengths required for bent, hooks and loop bars are larger than the lengths required for straight bars!
I would imagine that the opposite should have been required! A straight bar needs a larger anchorage length than a bent of hooked bar which, the latter, can hang on in concrete far better. Why the Eurocodes (and maybe other codes) require larger anchorage length for bent rebars?
I realized in the Eurocodes that the anchorage lengths required for bent, hooks and loop bars are larger than the lengths required for straight bars!
I would imagine that the opposite should have been required! A straight bar needs a larger anchorage length than a bent of hooked bar which, the latter, can hang on in concrete far better. Why the Eurocodes (and maybe other codes) require larger anchorage length for bent rebars?






RE: Anchorage lengths for straight and bent bars
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
https://www.facebook.com/AmericanConcrete/
RE: Anchorage lengths for straight and bent bars
RE: Anchorage lengths for straight and bent bars
If that table is correct then why would anyone ever hook rebar?
Like I said, not familiar with EC2. As best I can tell α1 is the factor applied to the basic development length lb,rqd and for other than straight per EC2 Table 8.2, α1 = 0.7 if you have sufficient clear cover for the bar. Thus, a proper hooked bar should have a lower development length per EC2.
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
https://www.facebook.com/AmericanConcrete/
RE: Anchorage lengths for straight and bent bars
RE: Anchorage lengths for straight and bent bars
Might be wrong on the details. Only touched Eurocode a few times.
I think you can also use more advanced equations and start doing things like using longer hooks and then count the bar length around the corner.
RE: Anchorage lengths for straight and bent bars
http://www.structville.com/2017/07/how-to-calculat...
The modifiers end up treating hooks really poorly on small amounts of cover.
I think that for hooks it's just the side cover that counts, though (I would need to look that up). The worry being something like sideface blowout, I presume.