Base Plate Hole Sizes - Cantilever & Moment Frames

[BatMan]

AISC Design Guide 1 lists recommended hole sizes of the base plate with respect to anchor rod sizes. These are much larger than AISC 360.
My questions is if the hole sizes of the base plate is that much larger than anchor rods to accommodate tolerances and erection, should the base plate be sized as slip critical?
For a cantilever or moment frames that takes some shear, the design guide recommends transferring the shear through friction or welded washer, but I have not seen this calculation done anywhere.
Or is it more or less of, "if it slips, then it goes into bearing, so what"...?

 

[JAE]

Slip critical connections are only made with high strength bolts (A325 or A490) so trying to achieve a slip critical connection with anchor rods won't really work.

For oversized base plate holes, the gap is made up for using additional washer plates with standard holes, that are placed over the rod extensions and then welded to the base plate.
We usually use a washer plate of 1/4" x 2" x 2" or something similar.

We also take significant base plate shear through embedded plates or other configurations - not usually through bolt shear, which I believe AISC frowns upon.



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[BatMan]

Thank you JAE.