Yup you guessed it, I went existential over the whole Fv readjustment and just never went back to fix it. Now they've added Emin... another rainy day job.
I had not seen your book of design values, Thanks! I wish they had added Fv to their table but the size factor and load durations are already done, that's a big help.
I've been using this one for design values, it has shear values and the new E-min value for columns but doesn't have the design value adjustments in table form by size as is done in yours.http://www.awc.org/pdf/2005-NDS-Supplement.pdf
Back to the problem at hand, there are girder and header tables in the IRC codebook , chapter 5 table R502.5(2) lists a double 2x10 good under a 20' wide building supporting one floor only at a girder post max spacing of 7'. In the tables that 2-2x10 girder is good at the perimeter as well. a 2x6 SYP joist is good for 9'9" in the tables, So that is the minimums. That floor combination vibrates at 14.1 hz so it performs worse than full span 2x12's that vibrated at about 14.7 hz.
This is where you can use the vibration program to see what combination of parts gives the best results for the parts invested. I interchanged different combinations, almost always "deeper is cheaper", going a size deeper usually has more effect on performance than adding another shallower width ply.
I was curious so ran some different combinations to see how the floor would stiffen up;
A code minimum floor rings at between 14.1-14.7 Hz. I think a tuning fork rings at 440 hz so this is a real dull thud.
The floor vibrates at 19.7 hz when going to 2x8 SYPine joists and double 2x10 girder
Go to a double 2x12 girder with 2x8 joists and it vibrates at 20.7 hz
With a double 2x10 girder and 2x10 joists it vibrates at 25 hz
With a double 2x12 girder and 2x10 joists it vibrates at 27.9 hz
With 2x12 joists and girder it vibrates at 34.25 Hz
Bumping the last option from #2 grade to Dense #1 raises the fequency to 36.33 Hz
Beyond the code and AWC minimums it is purely judgement as to how you want the floor to feel. My own shop building started as a flower drying barn and I framed it with 2x8's 12' spans on double 2x12 girders. it was fine till I brought in 3 engines a '35 Dodge truck, bundles of lumber, tools... I now need to crawl under that deadfall trap and insert midspan girders.
I went back to see how strong the 2x10' joists on 2x12 girders combination worked out to be, it was good for 7500 lbs overall on the girder and 1700 lbs per joist or 125 lbs per square foot... OK, guess I like a brick house for a shop floor
I went inside yesterday when the snow started and defected through some locust lumber just to kind of clean up and finish out the day. Boy I should have worn a mask. Both bloody nostrils and head running like a seive, thats some nasty stuff in an enclosed area.