ACI 318-11 7.10.5.6

[MacGruber22]

I am trying to figure out how this section applies to a square 30" spandrel column with (3) 36" deep beams (2 fascia/spandrel and 1 interior) framing into the column. *I* think that ties need to start at 1/2*S top and bottom of the slab, since there is at least 1 (exactly 1 in this case) free edges. A much more experienced engineer than I said that every detail he has seen and used for years would have terminated the column ties 3" from the btm reinforcement of the most shallow beam (in this case they are all equal).

The commentary has this section's verbiage dated to at least 1983, so I am a bit confused about the apparent disconnect between what it says, and what my elder engineer says.

Thank you.

"It is imperative Cunth doesn't get his hands on those codes."

 

[KootK]

If you don't run your ties through the joint at less than or equal to their regular spacing, the vertical bars in the outside face of the column may buckle.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[MacGruber22]

That is my take on it as well.

"It is imperative Cunth doesn't get his hands on those codes."

 

[TXStructural]

318-14 clarifies this in section 15 "Beam-column and slab-column joints":

R15.2—General
Tests (Hanson and Conner 1967) have shown that the joint
region of a beam-to-column connection in the interior of a
building does not require shear reinforcement if the joint is
laterally supported on four sides by beams of approximately
equal depth. However, joints that are not restrained in this
manner, such as at the exterior of a building, require shear
reinforcement to prevent deterioration due to shear cracking
(ACI 352R). These joints may also require transverse reinforcement
to prevent buckling of longitudinal column
reinforcement.
For regions where strong earthquakes may occur, joints
may be required to withstand several reversals of loading
that develop the flexural strength of the adjoining beams.
Chapter 18 provides requirements for earthquake-resistant
structures.

AND:

15.4.3 If longitudinal beam or column reinforcement is spliced or terminated in a a joint, closed transverse reinforcement is accordance with 10.7.6 shall be provided in the joint, unless the joint region is restrained in accordance with 15.2.4 or 15.2.5.

R15.4.3 Unless the joint is restrained on four sides by beams or the slab, reinforcement is required such that the flexural strength can be developed and maintained under repeated loadings (Hanson and Conner 1967; ACI 352R).

 

[MacGruber22]

Thanks, TX. I don't have the 318-14 code yet, but what you posted aligns with my intuition of the situation.

"It is imperative Cunth doesn't get his hands on those codes."