Horizontal bars on top of concrete pier

[windrunner888]

I came across a concrete pier design with horizontal anchor rod shear (HARS) bars shown in the plan view attached. I am wondering if these bars are required? It seems that from ACI 318-19 Section 10.7.6.1.6, the anchor rods are considered confined already due to the presence of the ties. The major load of the pier is bending moment and not located in the high seismic region. I heard that these bars cause a headache to install in the field, and would like to remove when the code doesn't specify the need. Any help to point out to the specific clause in the code will be very helpful. Thank you.

Edit: Not planning to remove it myself without EOR's permission. Just out-of-curiosity.

 

[WinelandV]

If the EOR is calling for it, I don't think there's any code clause that will allow you to say "we don't need this". Unless you're volunteering to seal the pier drawings yourself, I would recommend either 1) building it as is OR 2) asking the EOR if there's any way s/he could eliminate those bars.

Please note that is a "v" (as in Violin) not a "y".

 

[JoshPlumSE]

Confinement of anchor break out forces has gotten much more complex over the years. Especially when you start talking about "ductility". Unless you have a calculation that can demonstrate that they're not needed, and you have someone else to stamp the drawing, then you're stuck with those bars.

FWIW, they don't seem all that unreasonable to me. In my experience bars like this in a large pedestal can really help ensure accurate placement of the anchor rods.

 

[MotorCity]

If this is in a seismic area, those bars could be used to preclude some anchor rod or concrete limit state. For ductility, you either need to apply the overstrength factor (2.5??) or only use 40% of anchor capacity (1/2.5). This applies even in a moderate seismic area even though you're not in high seismic area. When in doubt, ask the EOR.