Ulitmate load to use for Anchor bolt check ACI - Ap. D

[SKJ25POL]

I have 25k uplift and 9.5k shear loas based on allowable strees method.
To check Appendix D ACI. I need to convert these to Ultimate loads (Nua and Vua), may I ask what above number has to be multiplied to so I can get correct value for Nua and Vua?

Thank you

 

[sandman21]

Where do the uplift and shear come from? EQ, DL, LL, WL? You would use the LRFD load combinations in ASCE 7-10 2.3.2 or ACI 318 chapter 9.

 

[SKJ25POL]

sandman21 (Structural,
These are the values I got from the drawings of a structure built 1954.
There was no break out of the numbers to tell me how much of it was what kind of load.
My assumption is the Uplift is due to wind load as well as shear.
So what will be the multipliers?

Is it wrong that I multiply Uplift by 0.9 and Shear by 0.85?(Vu=0.85Vn and Tu=0.9Tn)

Sorry my knowldge in this area is bit rusty. I appreciate the direction.

Thank you

 

[mike20793]

I typically use the ultimate load factor of 1.45 to convert ASD to LRFD.

 

[sandman21]

Allowable loads for wind are, Deadload + .6Wind Load. So to take the loads from allowable to ultimate would be 1/.6= 1.67 or 1.6. So your Tu=1.6*25k and Vu=1.6*9.5k. If you are looking for the phi factors they are applied to the Vn and Tn.

 

[SKJ25POL]

sandman21 (Structural), I thought Tn and Vn are the ASD loads but thibking more I am feeling they are the factored loads
so am I right the Tn and Vn are factored loads?
So there is difference between factor load and ultimate load?

 

[JAE]

Tn and Vn are the tension and shear CAPACITIES or strength in tension and shear. You do not factor those up, but rather down with phi factors.

Loads are factored up from service levels - for your unknown mix of dead, live, wind, etc. I'd use 1.5 to 1.6.

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[BUGGAR]

I tried to tell them this would happen if we left ASD.