# Need Verification: Combined Loads Finding Stress

1. Nov 16, 2008

### tangodirt

1. The problem statement, all variables and given/known data

I think I've solved this properly, but if you guys wouldn't mind verifying my work and pointing out any errors (if there are any), it would be much appreciated.

http://img391.imageshack.us/img391/6520/problemvm0.jpg [Broken]

I've already calculated the equivalent force-couple system at the plane of the elemental stress block, which is shown above. That's completely right, I know of it :). Now, I need to solve for the components of normal and shearing stress associated with that elemental stress block.

2. Relevant equations

$$\sigma$$Axial = P / A
$$\sigma$$Bending = Mc / I
$$\tau$$Shear = VQ / IT
$$\tau$$Torque = Tc / J

A = 12.57 in^2
J = 25.13 in^4
I = 12.57 in^2
Q = 5.33 in^3
D = 4 in

3. The attempt at a solution

Using the equations above, I've calculated:

$$\sigma$$Axial = 477.46 psi
$$\sigma$$Bending = 12,414.09 psi
$$\tau$$Shear = 106.10 psi
$$\tau$$Torque = 5729.58 psi

Did this all with excel :).

Do those answers sound right? The next step which I am having difficulty with is calculating the $$\sigma$$X, $$\sigma$$Y, and $$\tau$$XY. I understand that I'm just using super position for this, but I'm not sure whether to add or subtract the two.

Thanks!

Last edited by a moderator: May 3, 2017