Standard Hook for horizontal bar

[CWEngineer]

Trying to figure out the criteria for providing a standard hook in a horizontal rebar. I have seen statements to use a standard hook on a horizontal rebar if you have a top bar or 12 inches of concrete below, but have not seen that in ACI 318.

Also is a standard hook required for a horizontal bar that serves the purpose of temperature/shrinkage reinforcement?

Appreciate your help.

 

[JAE]

"Top bar" condition where development length must be increased is found in ACI 318-11 in section 12.2.4(a).
Usually don't hook temp/shrinkage rebar.

Check out Eng-Tips Forum's Policies here:
faq731-376

 

[StrEng007]

CWEngineer,
Don't get your equations for straight bars development length and hooked bar development length mixed up. The factor for the amount of concrete cast below the bar, that JAE referenced for you, is applied to your development on straight bars.

Hooked bar development length equations are found in Section 12.5