Punching Shear in Isolated footing with moment in kips

[Buleeek]

Hello everyone,

I'm trying to compare my hand calculations for punching shear (with Moment and Force) with computer program and the result is a little off. I would like to make sure I use the right values. See below:

The maximum shear stress for both moment and force is given as: vu = Vu/(bo*d) + gamma.v * Mu * y / Jc
My question is, what should I multiply that formula ("vu") to receive the value in force (kips)? When I multiply "vu" by (d*bo) I get slightly different result. Should the part of the formula with moment be multiplied by something different than "d*bo"?
Thank you,

 

[KootK]

Should the part of the formula with moment be multiplied by something different than "d*bo"?

Yes, that's right. I don't think that it's possible to reduce this to just a "kips" answer. Rather, it will need to be a answer of the form [P x e = Axial Load x effective load eccentricity]. Unless I'm missunderstaning your question, that sounds like it would be just [P = Vu; e = Mu/Pu].

 

[HTURKAK]

The subject formula for punching stress has two components . The punching shear stress vu, is the summation of two components: 1) direct shear stress, and 2) shear stresses due to unbalanced moments transferred from the slab to the column.

- If you multiply ( vu ) with (bo*d) , you will obtain equivalent nominal load ( Vu , without moment effect ) which produces the punching stress ( vu ) ..

- If you multiply ( vu ) with ( Jc/ gamma.v * y ), you will get nominal unbalanced moment without axial load effect ,which produces the punching stress ( vu ) ....


Note= You can add apples with pears but you must change the units , say no. of fruits...