Ld, Ldh Differences; Ldh + L

[nohjzqrun]

Good Day. What's the diff. between development length for straight bars (Ld) and for hooked bars (Ldh)? Is the addition of a Bent or L(extension) Bar on Ldh have the same effect with Ld? Or should I just use Ld and bend it?
Thank you for the responses.

 

[MotorCity]

Use either the straight development length or the hooked development length. The hooked development length is shorter than the straight development length. You could put a hook at the end of the straight development length, but it would serve no purpose. There is no code provision that I am aware of that lets you double dip (i.e. calculate the development length of a hooked, straight bar).

 

[nohjzqrun]

Thank you for the response. I am quantifying the rebars needed for beams and im confused on what to consider for the junction of a column and a beam (discountinuous end).
Should I use development length or (Ldh + Bent/L extension)?

 

[MotorCity]

You should use the hooked development length + the hook. Unless your column is wider than the straight development length, the straight development length won't work.

 

[DaveAtkins]

I am confused about your question. A bar with a standard hook is developed in the distance ldh from the bend. There is no reason to add the length of the extension beyond the hook to the hook development length.

DaveAtkins

 

[humanengr]

You would use Ldh (STANDARD Hook Development Length) to determine the requirement development length of the rebar. The hook details and dimensions must meet the STANDARD HOOK requirements
(90 degree or 180 degree hooks) - referring to ACI-318 definitions.