Masonry - Rebar Development Length

[RFreund]

Is the development length of a bar in masonry allowed to be reduced by As provided / As required, similar to concrete? If so, I can't seem to find this in TMS 402 (aka ACI 530). Any suggestions to where I can find this?

Thanks!

EIT

http://www.HowToEngineer.com

 

[JAE]

Have never seen that in the masonry spec - nor have I ever used that reduction for masonry.

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[DaveAtkins]

While I agree with JAE, I think you can use engineering judgment to justify reducing development length. It makes sense that a lower force in the bar would require a shorter development length.

DaveAtkins

 

[RFreund]

JAE - I was hoping you would respond and I hate to do this, but there was this thread from a long time ago... LINK... where you might have thought otherwise? Now you can see why I was hoping you would respond. Again, no disrespect meant, maybe you thought that they were referring to concrete. Or maybe it is just an obvious extension of the code. Or maybe it only applies to lap splices, but I can't find that either.

EIT

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[masonrygeek]

While the development length requirements for masonry have varied over the years, I don't believe that they ever included the As provided/As required provision. I would recommend to use the most current version of TMS 402 (ACI 530) and use the requirements for development length from that standard. Most current version is TMS 402-16. If you don't have a copy, you can get it here:

https://masonrysociety.org/product-category/tms-pub/.

 

[JAE]

RFreund - no problem! Thanks for the link and recall. I don't specifically remember if I was thinking that this was a masonry extension to a concrete wall (when in fact it was a masonry wall).

masonrygeek is correct and I checked TMS 402-13 again with nothing in there included for As(req'd) / As(prov).

I might have been thinking that the rebar was in "grout" - a minor form of concrete but probably not.
More likely I was probably thinking in line with DaveAtkins comment above about using engineering judgement on this - if the moment was very small perhaps some "judgemental" reduction in ld could be tolerated.

Not sure I'd use the full ratio of As(r)/As(p) though.



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[RFreund]

Thanks for the follow up.

Still seems very odd to me that there isn't something like this in the code.

EIT

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