ACI 350-06 Section 10.6.5 - Concrete Cover & Maximum Bar Spacing 1

[JoelTXCive]

Below is a snip from ACI 350-06, Section 10.6.5.

I have 2 questions and 1 complaint:

Question 1: Is there a typo in the code provision? The code provision says 'exceeds 3" inches,' but the commentary discusses exceeding 2" inches? Is the 3" correct?

Question 2: Is the f_s in equation 10-7 the maximum permissible stress per equations 10-4 & 10-5? Or is the f_s the stress at service level? I believe they mean the service level stress here, but figured I would see if anyone feels differently.

Complaint 1: Unless I am reading the equation wrong, the units do not work. I though that ACI did not do that? You have 540 divided by ksi minus 2.5 times inches.

Thank you.

 

[r13]

1) No. For any reason that the actual cover is greater than 3", then spacing the reinforcement per EQ 10-7, but use 2" in EQ 10-4 & EQ 10-5.

2) fs is stress due to service load (non-factored).

3) 540 is an experimental number, I believe.