Minimum Closed Stirrups for Torsion

[CWEngineer]

From ACI Sec. 11.6.1 torsion can be neglected if Tu is less than (phi)(f`c)^.5(Acp^2/Pcp).

Say if my Tu is less than the above value, but I still want to place closed stirrups because torsion is present, Is there a minimal standard size that is acceptable to use?

THANKS

 

[WillisV]

Since additional torsional stirrups are not required in this case then using the minimum stirrups required for shear as closed stirrups would be adequate.

 

[chichuck]

I concur with WillisV, but with the following additional point: use closed ties, or stirrups with an added closing top bar, not just stirrups alone. This is required for torsion resisting ties.

regards,


chichuck