Shear Flow Calculation

[PowerStud]

What is the best method to calculate shear flow (longitudinal shear). I have a method that I have been using, I was just wondering if someone else did it differently. Just let me know if you have ideas.

 

[UcfSE]

I use f (shear flow) = VQ/I. V = shear force, Q = statical moment, I = moment of inertia. That assumes elastic behavior for a homogeneous elastic material and plane sections remain plane (linear strain distribution).

 

[PowerStud]

That's what I use now, but it equates to psi. How do you then use that to determine fastener requirements on that plane?

 

[JAE]

VQ/I ends up with kips/inch or pounds/inch.

Kips x In^3 / In^4 = kips/inch

 

[UcfSE]

It is force/length. F*L^3/L^4 = F/L

You might be thinking of tau = VQ/It where t is the thickness of the section at that location. That is stress.

 

[PowerStud]

You're right. That's what I normally use. Sh=VQ/Ib. I omitted the b in this case and divided the lb/in result into the allowable shear force for the fasteners I'm using to determine the longitudinal spacing in inches. Thanks for the help.