Stirrups

[Iasonasx]

I was looking at SE exam problems and ran into a situation. They give a standard problem where we determine the stirrup spacing based on the necessary ΦVs, then compare it to the maximum spacing allowed by the equations of the code, etc. However, I always considered that the 1st stirrup has to be 1/2 the maximum spacing for the Vu at distance d from the face of the column. To my surprise, and chagrin, the "correct" answer did not apply this standard practice that I have been taught in college, I see in textbooks, and have been practicing for more than a decade. So is it a mistake by the NCEES or was I taught that wrong?

 

[dik]

What is their correct answer?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Iasonasx]

The ΦVs requires 12.68" spacing, the d/2 is 10.75". Given the above, I picked the answer that is 6" because it 1/2 the 12" (truncated) given by the ΦVs required, and it is safely shorter than d/2. Their correct answer is 10". My configuration would have been 6" for the 1st spacing and then continue with 10". I would not start with 10".

 

[hokie66]

I would have started with 6", then 12". But since d/2 is more than 10", I suppose they can justify 10" as the correct answer.

 

[Iasonasx]

@hikie66, I would have started w/ 6" and then keep it down to 10 per code, and that would have been my design, but I don't see how they justify the 1st being 10. Perhaps that is "since 10<12 and we start and continue w/ a value lower than the minimum calculated spacing for ΦVs, the spacing is adequately dense at that location already."