RCSC Turn of the Nut Specified Rotations 2

[BMart006]

Alright bolt experts, help me understand something. I'm a little confused based on the reading I've done to this point on pre-installation verification and its purpose for bolts installed via the turn of the nut method. An AISC Steelwise article from 2015 (The Nuts and Bolts of Nuts and Bolts) indicates that pre-installation verification is required for ALL pretensioned joints, and this seems to align with RCSC section 8.2. However, RCSC section 8.2.1 for turn of the nut makes no mention of pre-installation verification as 8.2.2. does for calibrated wrench pretensioning. Rather it states that the rotation shall be as specified in Table 8.2.
So here's my confusion: What is the purpose of pre-installation verification when turn of the nut is to be used? I would think, if anything, it's to establish the amount of rotation needed to reach the minimum pretension, but then it seems those results would be neglected by the instructions of 8.2.

 

[jdonville]

Send your question to solutions@aisc.org . They are seriously good about answering questions like this (potentially contradictory code issues).

 

[DrZoidberWoop]

Think of it like a procedural/QC aspect of the job, rather than a pure technical issue. Pre-installation verification is a quality control method to ensure the particular bolt assembly is going to achieve the required tension. That's all. Also, section 8.2 is more general and states that all bolt assemblies shall be tested using the pretenstioning method to be used on the job site. Under contract requirements, qualified QC personnel should have the ability to decide to either 1) establish acceptable levels of variance from RCSC Table 8.2, based on pre-installation verification results, or 2) defer to EOR.